PDA

View Full Version : Guide/tutorial to some plastics and materials


Nara Shikamaru
07-10-2006, 02:02 AM
I just want to clear up a few things on this thread, because I know they get confusing to a lot of people so I'd like to help set things straight.

I've build combat robots as a hobby for many years now and I know about most of these materials.

Clear Plastics:

Acrylic is Plexiglass.
Plexiglass is the name brand of sheets of Acrylic used to replace glass windows, hence the name. It's no different then how a lot of people call tissues Kleenex a lot of time. Kleenex = brand name, tissues = generic name for the item.

Also acrylic can be bonded chemically with CA (cyanoacrylite) glue, aka most superglues, to create (supposedly) seamless clear bonds.

On a similar note:

Polycarbonate is Lexan.
Lexan is GE's brand name for polycarbonate. It's a clear impact resistant plastic which is also used for window replacement.

The differences between acrylic and polycarbonate are this. Polycarbonate is a lot stronger. While in the cosplay field that usually won't matter much, it can. Acrylic tends to crack/fracture like glass does. It can leave some sharp edges and potentially break if you drop it depending on how heavy it is. While polycarbonate won't crack or shatter it's typically a lot more expensive. However if you plan to drill through acrylic be very careful as it will chip or break if you do it to fast.

How to tell the difference:

The best way is to read, wherever you're getting it from will probably say. If you're buying it from the window section of Home Depot or Lowe’s I believe typically acrylic is covered in a clear blue film while polycarbonate is in a clear green film.

If you have some clear plastic and you aren't sure what kind it is there's an easy way to distinguish the two. Take a file or some cutting tool and rough up the end a bit. If it's acrylic it should give off a pretty strong odor similar to the places in malls that do fake nails, because yes, those are made of acrylic.

Resins

There are two main types of resins. Epoxy resin and Polyurethane resin. These can both be used by themselves or with fiberglass cloth.

Polyurethane resin is pretty harsh stuff. It gives off strong chemicals and should be used in a place with proper ventilation. It comes in a big metal can similar to paint thinner and has a small tube of catalyst which is used for hardening. The little tubes of MEKP (Methyl Ethyl Ketone Peroxide) can be bought separately. Each brand will give their own ratios of resin to MEKP but it's typically about 8 drops per ounce of resin. The good part about this type of resin is it dries fast and the ratio is more of an art than a science as the catalyst only creates a chemical reaction that causes heat to cure the resin. If you're a little off in your mixture it will still harden it just might do it too fast or take a long time. This stuff will eat away pink insulation foam, so don't use it on it unless you seal it with something first.

Epoxy resin on the other hand is much nicer to work with. It doesn't have much of a smell at all. It won't eat away at foam. The downside is it typically dries a lot slower than polyurethane resin. Also it typically comes in a part A and part B. If you don't mix them evenly it can end up tacky or take a long(er) time to dry.

Other plastics:

There are a lot of other plastics you can use for various things. I'd recommend reading around on distributor’s websites to get more information.
Some of them include:

Polystyrene - Most commonly found as extruded polystyrene, aka pink insulation foam. This is pretty good stuff to work with but the vapors given off when melted or even sanded vigorously aren't healthy, so work in a well ventilated place.

Carbon Fiber - Sold in thin sheets, this is a laminate material often used for it's strength and light weight or because the weave looks nice. You can also lay your own in a similar fashion to fiberglass but I imagine it would be hard to get the weave to look nice.

Polyethylene - This might be outside the scope of most builders on here but it's a nice material to work with. It's easily machined, as a nice smooth slippery texture, and can be dyed with fabric dye. It's commonly found as HDPE (High Density PolyEthylene) or UHMW (Ultra-High Molecular Weight polyethylene). I belive this is the material commonly used for cutting boards so that's what the texture is like.

Where to Buy:

Most of these materials can be bought at local hardware stores, such as Lowe's or Home Depot, but there are a lot of online resources as well. One word of caution though is to watch out for shipping costs on really big or really long pieces.

Tap Plastics (http://www.tapplastics.com)
McMaster-Carr (http://www.mcmaster-carr.com)
MSC Direct (http://www.mscdirect.com)

There are a lot of others too but those are the 3 I most often use. If you're lucky enough to have a Tap Plastics store near you I hear they are really helpful there. I unfortunately live on in New Hampshire. :(

I hope this helps inform some pople. Just remember there's pleanty of knowledge out there but sometimes you have to look.

Phinal_Phoenix
07-10-2006, 07:28 AM
Nice! This will definitely help me in the future~... :D

RevGirl
07-10-2006, 02:16 PM
THank you so much I was getting all these confused! ^_^

chisainekocat
09-28-2006, 11:28 AM
Hi, I was wondering if the plastic balls in the picture below would be too heavy for earrings. The size I want are 1'' in diameter.

http://www.tapplastics.com/shop/product.php?pid=135&

verdatum
12-06-2006, 11:31 AM
I just wanted to say this is an excellent post.
To add to it, I want to mention PVC (Polyvinyl Chloride) and ABS (Acrylonitrile butadiene styrene)

These are used in the construction of things like Stormtrooper armor, as they melt readily to use with vacuforming.

calen383
12-06-2006, 02:27 PM
Rad. *bows down to the plastic master*

PrincessYuni
12-06-2006, 04:16 PM
Wonderful Information. You, my friend, have been added to The Tutorial List.

nobodysktr
05-16-2007, 04:04 PM
where can i buy epoxy resin? can i get it at home depot or lowes and in what department do i look? also where besides online can i get RTV or any kind of silicon mold making kit

Alex Evangelou
05-17-2007, 02:46 AM
where can i buy epoxy resin? can i get it at home depot or lowes and in what department do i look? also where besides online can i get RTV or any kind of silicon mold making kit

Wow brough this back from the dead.

You can buy epoxy resin at Home Depot/Lowes though depending on how much you need that could get expensive. You can check marine supply stores as there is lots of fiberglass and resin used in boat construction. Again though you'll have to check to make sure it is epoxy resin.

Silicon RTV is a little harder. If you have a TAP plastics near you they should have some mold making stuff and I've heard the people there are very friendly so they should be able to get you started easily.

Though smooth-on.com is a very widely used online supplier so if you have to resort to buying online I'd check them out.

Honey Usagi-chi
06-21-2007, 02:16 PM
Hi, I was wondering if the plastic balls in the picture below would be too heavy for earrings. The size I want are 1'' in diameter.

http://www.tapplastics.com/shop/product.php?pid=135&
I know it's a little late to reply, but resin casting with paint trays as molds will give you your size and will be lightweight ^_^

vasher
06-21-2007, 03:15 PM
Do you know if polyester resins will eat through polyisocyanurate (man, what a mouthful) foam? My local Home Depot has been stocking that along with polyurethane/styrofoam for insulation purposes and it's supposedly a more stable compund.

I don't have any polyester resin on hand or I'd be experimenting myself. XD

verdatum
06-21-2007, 04:04 PM
Do you know if polyester resins will eat through polyisocyanurate (man, what a mouthful) foam? My local Home Depot has been stocking that along with polyurethane/styrofoam for insulation purposes and it's supposedly a more stable compund.

I don't have any polyester resin on hand or I'd be experimenting myself. XD

Neat, first I've heard of this stuff. Sounds like a very interesting product.

I did some research on fiberglast.com and it appears that the product should not melt via polyester resins (though they don't explicitly say so).

I found a couple different sources that said not to hotwire it, but it responds very well to traditional cutting tools.

--I DO have some polyester resin on hand...but no foam, or I'd be experimenting myself :)

Edit: Nevermind. Confirmed. Apparently this is another (more accurate) name for polyurethane foam.

"Unlike polyester foams, polyurethane foam is compatible with both polyester and epoxy resins. "

"Polyisocyanurate Foam Sheets:
Our polyurethane foam sheets have the same properties as the mix and pour foam listed above, but come in rigid sheets of varying thickness"

Alex Evangelou
06-21-2007, 11:46 PM
Yeah while this isn't a 100% gaurenteed answer I would say that it would most likely work if it's not polystyrene.

It's the styrene monomer in the polyester resin that breaks down the foam structure of the polystyrene foam so as long as it's a compound made from diffferent base molecules (be it icynene or urethane) there shouldn't be an issue. So general common sense says it should work.

Verdatum: I don't believe it's the same as polyurethane foam. From what I've read in the past polyurethane is made from the mixture of isocyanate and some other compound. (I forget off hand) So they probably share some similar properties



Also good to note:
"Isocyanates are the leading cause of workplace-related asthma and pulmonary disorders in the United States (according to NIOSH & OSHA)."

The smoke from it is toxic, but then again so is the smoke from polystyrene foam. :toothy:

AnimeLore
08-21-2007, 11:16 PM
OK, I'm pretty sure i'm going to use epoxy resin to cast some buttons I need to make. My question is: the buttons are silver - is there some kind of pigment I can get to cast them in silver? Where can I get it? If not, will spraypaint work to paint them once theyve hardened?

Thanks!

vasher
08-21-2007, 11:30 PM
Ahem- yes, TAP Plastics (possibly Michaels/local craft store), yes. ^^

You can get resin dyes to color your casts, or you can paint your buttons after they've hardened. I actually have a 1 oz. bottle of sparkly silver dye right in front of me, heh. Dye is nice because even if your cast gets chipped, it won't show a different color, but it's a bit more expensive than your run of the mill spray paint.

verdatum
08-22-2007, 12:53 AM
That's interesting vasher, I didn't know they had resin dyes in a great variety of colors.

Another thing that can be done with resins to get a metallic effect is to add aluminum powders. However, you'd have to be extremely careful with this stuff, as aluminum in particulate form is quite toxic to inhale. Never messed with it myself.

AnimeLore
08-22-2007, 02:45 PM
Ahem- yes, TAP Plastics (possibly Michaels/local craft store), yes. ^^

You can get resin dyes to color your casts, or you can paint your buttons after they've hardened. I actually have a 1 oz. bottle of sparkly silver dye right in front of me, heh. Dye is nice because even if your cast gets chipped, it won't show a different color, but it's a bit more expensive than your run of the mill spray paint.

where do I get the dye? Is there a website I can buy from? And what is it called so that I can see if my craft stores have it.

thanks again - I'm sorry for all these questions. I'm just about to start working on this costume and there are a bunch of things I'm doing for the first time for it, so i have a ton of questions lol. Thanks for putting up with me.

verdatum
08-22-2007, 03:46 PM
It's usually generically called resin dye. The brand I usually see in craft stores is related to the "castin' craft" product line.

http://www.tapplastics.com/shop/product.php?pid=50
http://www.fxsupply.com/pigments/resin.html

There are many other manufacturers & resellers. But I'll leave that to you and google :)

All you need to know is that resin dyes are different from most other dyes (largely because liquid resin + water = BAD)

And pure (sometiems called universal) powder pigments should also work. However, they are much harder to properly mix and harder to repeat the same color twice on additional runs because they're so concentrated and difficult to measure.

AnimeLore
08-22-2007, 10:43 PM
Thank you for the links, verdatum! The only problem is neither of those sites seem to have silver. The problem is that neither of them has silver pigment, and I can't seem to find a site that has it. One of the sites you provided does have a pearl transparent dye and a gray opaque one - do you think mixing them would give me that metallic silver color? I'm afraid of spending the money on them only to find that the effect is totally not what i was hoping for.

linkluver6
01-25-2008, 05:10 AM
does any one know anything about
manipulating dielectric plastic??

the plastic used on hard hats
i was talking to a friend of mine about costumes and i just got curious
because I might wanna use that shiny plastic look for parts on armor
I have seen what it looks like dielectric of similar plastic
used on huge plasitc armor in japan
thanks

verdatum
01-25-2008, 08:22 PM
Wow that's interesting stuff:
http://www.google.com/patents?id=i-llAAAAEBAJ&dq=patent:3067141
I don't know much about it other than it's nonconductive to electricity, and it's used in safety equipment. The only resources I can find about buying it are industrial contacts...

Devi 1313
01-30-2008, 12:46 AM
Hello, I was thinking of using some sort of plastic for Sumomo's hat from Chobits. Any idea what type of plastic is smooth, white and easy to manipulate? I need to shape it into something similar to a bundt pan, except with a smaller base. The top will be mostly flat but with rounded edges and a funnel in the center. I'd post a pic, but none of them are very helpful so I'm sort of doing my own thing. There is a Tap Plastics located near my mom so something that could be bought there would be excellent!

KillaBeeSwarm
01-30-2008, 11:33 AM
@Devi 1313: Wonderflex, though you'd have to use something to make it smooth and Wonderflex isn't sold at retail stores.

Devi 1313
01-30-2008, 09:06 PM
I was hoping to use something smooth though so it would look just like factory molded plastic as opposed to something painted and possibly lumpy.

verdatum
01-31-2008, 04:41 AM
From what I know, you probably want sintra, which is a rigid foam PVC sheet plastic that can easily be formed with heat. I haven't used it myself, but searching this board should give plenty of info.

Of course, the only way to get a good factory molded plastic look is to...factory mold it. By which I mean, you'd need to look into vacuforming. But I believe the technique of manually shaping sintra should achieve a close enough effect to what you desire.

Devi 1313
02-02-2008, 01:49 AM
So something like this, correct? http://www.tapplastics.com/shop/product.php?pid=343&
I'll be sure to ask them all about it. Thanks!

verdatum
02-02-2008, 05:28 AM
My apologies! I spelled it wrong. The brand name is actually "Sintra" not "Cintras", and it's actually a rigid PVC foam (I edited my previous post accordingly). If you wanted to go with tapplastics, their generic equivalent would be this stuff:
http://www.tapplastics.com/shop/product.php?pid=342&

the PVC sheet you referenced can potentially be used as well, I believe it's just a bit harder to shape by hand. Again, my experience is minimal, the main thing I know is that Wonderflex and Sintra are the two main type of thermoformable sheet plastic I hear about here.

Devi 1313
02-02-2008, 10:18 PM
Oooh, ok. I'll ask them all about it when I go up there next week!

standrdsmile
02-06-2008, 04:27 PM
I've always been really confused about resin... I've always want to work with it but never really knew how. Do you have to use a mold or can it be sculpted. I have no idea.. because i would really like to try making my props from it.
:)

Aera
02-19-2008, 01:42 PM
I was planning to do a sword with a clear blade with some petals enclosed in it. I guess I'll need to use resin for the blade. But I'm afraid, that because of the length of the whole thing, it will break. Does anyone has some experience with casting such long objects from resin?
And what kind of resin would you recommend? Plus are there any ways of preventing the resin from breaking? Like putting some kind of core into the blade?

TwilightAmelia
02-23-2008, 10:59 PM
Can resin, once it has hardened, be sanded?

invisiblecake
06-03-2008, 12:17 AM
Hi. I just joined to ask about this.

I'm planning on making Edward Elric's automail arm and leg (Full Metal Alchemist) as armor, and I want it to have an internal structure based heavily on the new Iron Man movie, so that it will be easilly removable and such. However, I don't really know what to make the internal parts out of. I need somthing light weight, and relatively thin, that can be easilly bent (I'm hoping for something that doesn't need a lot of heat, as I will have to hold it against my arm to shape it) and will hold it's shape well afterwards.
The color is not important, although if I could use a resin and dye it, I'd love to make it a silvery or pearl color. But if I did that, I wouldn't know what to make the pieces for the mold out of, because they would need to be pretty smooth and flat.

Any ideas? My goal is to get the internal parts ready by Convergence in July. Thanks! And here are some images.

http://i283.photobucket.com/albums/kk297/invisiblecake/sk103.jpg
http://i283.photobucket.com/albums/kk297/invisiblecake/photo_21_hires.jpg

Aokiyai
06-03-2008, 08:20 PM
This is a bit of a silly question, but I've seen people use thinnish styrene sheets for prop making and I was wondering where one could buy them? And, er, really what they kind of are? XD;; I wiki-ed it and it gave me the chemical make up and history which I did not need at all, but I didn't go into anything more extensive because it was way past my bedtime. >>;;

Fong
06-20-2008, 11:55 PM
So is there an in-between step for epoxy resin--such as latex/gesso? I understand it wont make the foam melt....

Should I paint the prop pre or post epoxy'ing?

I'm just unsure of the order of things >.< Any clarification would be greatly appreciated!

Also: Could anybody link me to a prop that was made of out epoxy? I'm curious to see what it looks like.

kimuhalu
09-23-2008, 10:47 AM
Thread rez! Seriously this thread needs to be stickied. Everyone says 'use resin', I say 'what kind'? This thread answers it nicely and clears up a lot of other questions. :)

verdatum
09-23-2008, 08:38 PM
k, feels wrong to let these questions hang around unanswered. even if some of these are a bit late:

I've always been really confused about resin... I've always want to work with it but never really knew how. Do you have to use a mold or can it be sculpted. I have no idea.. because i would really like to try making my props from it.
:)
The short answer is, it cannot be sculpted. The longer answer is, there is an epoxy resin product that is in the form of a putty. You knead the two parts together until the colors blend, and it can be sculpted. I've seen people do amazing things with it. PERSONALLY, I don't have 1/100th the sculpting skills needed to get the piece looking the way I like before it starts to harden. Still, it's nice for filling smallish gaps in propwork. Also, there is resin/fiberglass layup over a foam core, which is niether a mold nor sculpting, but that's discussed in enough places already.

I was planning to do a sword with a clear blade with some petals enclosed in it. I guess I'll need to use resin for the blade. But I'm afraid, that because of the length of the whole thing, it will break. Does anyone has some experience with casting such long objects from resin?
And what kind of resin would you recommend? Plus are there any ways of preventing the resin from breaking? Like putting some kind of core into the blade?

clear + thick is difficult. There are special varieties of polyurethane resin that are able to achieve this very well. Unfortunately, to get it done right, you need to use a device called a "pressure pot" (or an autoclave) to squish the naturally forming airbubbles down to invisible size as it cures. Neither is cheap, and both can be hard to find and borrow. As far as embedding goes, there is a product called castin' craft (http://www.eti-usa.com/consum/castresn/castresn.htm) that provides lots of instuction to the do-it-yourselfer on embedding stuff like petals into resin. It's a polyester resin instead of polyurethane. That means more oder and less ability to get super thick (though I don't believe a sword is too thick. I haven't used either product, but I expect the more expensive clear resins from polytek or smooth-on would be stronger. The later are often used to make things like clear trophies and awards. Powdered Acrylic is another product that can be used. and it is very strong (same stuff as clear plexiglass once cured properly) but it is super cloudy without that pressure pot. Moreso than the friendlier materials. If you watch the "How it's made" about "acrylic awards" it shows you the whole process, but it's not very feasible on a small scale. (and once again, really nasty chemical).

Can resin, once it has hardened, be sanded?

Resin sands better than just about anything in existence. You can go up to 3000 grit sandpaper, and keep on going to car rubbing compounds and polishes, and get resin mirror smooth. However, resin dust is REALLY NASTY. you need a HIGH GRADE respirator that is rated to work with plastic dust. Not just a cheap "dust mask" or a bandana over your face.

This is a bit of a silly question, but I've seen people use thinnish styrene sheets for prop making and I was wondering where one could buy them? And, er, really what they kind of are? XD;; I wiki-ed it and it gave me the chemical make up and history which I did not need at all, but I didn't go into anything more extensive because it was way past my bedtime. >>;;

If you want a place that is web-friendly, I reccomend "Tap Plastics". If you want something local, for some odd reason, the best source is still the yellow pages under "plastic suppliers". They are all over the place, but for some reason, it's often really hard to learn about them from the internet. Sometimes if you get one that is small and friendly enough, and you aren't picky, you can get random scraps for free.

So is there an in-between step for epoxy resin--such as latex/gesso? I understand it wont make the foam melt....

Should I paint the prop pre or post epoxy'ing?

I'm just unsure of the order of things >.< Any clarification would be greatly appreciated!

Also: Could anybody link me to a prop that was made of out epoxy? I'm curious to see what it looks like.

It depends on the effect you are going for. but basically, with resin over foam, the resin acts as a surfacing agent. You use first, so you can have a hard surface you can then sand down to a truely flat surface. If you don't paint over a flat surface, the paint will look bad, no matter how many coats you apply. STILL, after you lay down the epoxy, sand it smooth, and paint it, you may want to "topcoat" it. A thin layer of slow cure epoxy is excellent for this. The topcoat is critical to get that super-glossy mirror like finish. The topcoat is a major part of what makes things like new cars look so spiffy.

verdatum
09-23-2008, 08:43 PM
So yeah, funny this thread should get revived. I just noticed a slight error in the original post. The section that talks about "polyurethane resin" (coming in metal cans and you mix it with the MEKP catalyst) is actually talking about polyester resin. Polyurethane resin is also referred to as "liquid plastic". When you hear about "resin miniatures" or Ball Jointed Dolls being resin, they are talking about this stuff. it's a two part system, these days often an easy 1:1 mix ratio. There are still toxicity issues, and it should still be used in well ventilated areas, but it has faaaaar less maloderous fumes than polyester resin. It is also designed to deal with the generated heat better. A thick buildup of polyester resin will get so hot that it will actually deform and crack or even spontaneously combust. Polyurethane is designed so it may be cast into larger molds.

kimuhalu
09-23-2008, 11:18 PM
Ok, so about epoxy resin. I called around and went to a couple stores today asking if they had this stuff. Even though they said "yes" I doubt it's the right stuff. What they carried was an adhesive. I'm assuming there are two types, the adhesive and the other one (which I would need)? Would I find it at someplace like Lowes?

MightyWeresquid
11-19-2008, 03:31 PM
Is it possible that you could make a sword blade with just polyester resin? I know you can make jewels for cosplay out of it...

verdatum
11-21-2008, 09:33 PM
Ok, so about epoxy resin. I called around and went to a couple stores today asking if they had this stuff. Even though they said "yes" I doubt it's the right stuff. What they carried was an adhesive. I'm assuming there are two types, the adhesive and the other one (which I would need)? Would I find it at someplace like Lowes?
the epoxy resin sold as an adhesive is effectively the same stuff as the epoxy resin used in fiberglassing. The difference is in the cure times, the thickness, and the cost. You pay a lot more per ounce to get it in those little tubes than you would to get a bucket of the stuff.

Is it possible that you could make a sword blade with just polyester resin? I know you can make jewels for cosplay out of it...
The problem is you can't use polyester resin to cast things that are really thick. Polyester resin generates lots of heat as it cures. And thick portions of polyester resin sorta works to insulate itself so it can get even hotter. All that heat puts stress on the piece, and will cause tiny cracks throughout it. Without the reinforcing power of the fiberglass, it's very brittle, not the sort of thing that can survive a con.

akaisha0
12-09-2008, 03:19 PM
Also, there is resin/fiberglass layup over a foam core, which is niether a mold nor sculpting, but that's discussed in enough places already.


I don't know if anyone still comes here but can anyone point me in the right direction to find more information about using resin and fiberglass over a foam core? I'd like to start practicing different methods so I have a better idea for cost and what to do when I finally take on Dark Knight Rikku.

Ki-san
12-20-2008, 09:41 PM
I'm thinking about making a prop out of plexiglass, but the blade of the sword is a smoky grey/blackish, but still translucent. Would I be able to use a paint or a dye to color the glass, or would I have to get a specialty product?

verdatum
12-20-2008, 09:56 PM
I'm thinking about making a prop out of plexiglass, but the blade of the sword is a smoky grey/blackish, but still translucent. Would I be able to use a paint or a dye to color the glass, or would I have to get a specialty product?

For the best effect, you'd want to get intrinsically colored plexiglass. Like so:
http://www.tapplastics.com/shop/product.php?pid=341

Saltina_major
12-25-2008, 09:25 PM
I'm looking for a transparent plastic that can be easily formed in a way similar to wonderflex. I don't need to sculpt or cast anything, so I dont think I would use an sort of resin. I'm thinking of a thin acrylic sheet, but I'm not sure what kind of heat I would need to apply in order to manipulate it. Any suggestions?

Lucrezea
12-29-2008, 06:46 PM
Alright, I've done nothing but research for the past few months. Now I need some help clearing a few things up. I sincerely apologize if any of this has been clarified, as chances are the answer was a quick two-word response to someone and I missed it.

For insight, I am asking these questions from the view of wanting to work with rigid insulation foam as a base for both small and large weapon props.

Resin
While comparing countless threads, I've seen polyurethane resin and polyester resin used to describe the same thing. For example, both have been used in reference to be "the type of resin that melts foam". Is this a typo on behalf of someone and they actually have different properties, or are they the same thing?

Fiberglass
I've seen fiberglass referenced to being both resin and cloth. I am assuming what people are intending to reference is fiberglass cloth (which would then be coated with one of the various resins). Is this correct, or is actual fiberglass resin being referenced? If so, would using fiberglass resin be simpler than using fiberglass cloth with a different type of resin on top?

Joint Compound
I've seen joint compound listed as something that can be used as simply a filler, or to actually coat and strengthen an entire prop. Is this worth considering, or would it be too prone to chips and cracks?

Thanks to anyone that has the knowledge and time to answer. I'll have a few follow-up questions once these points are clarified.

verdatum
12-30-2008, 12:18 AM
Resin
While comparing countless threads, I've seen polyurethane resin and polyester resin used to describe the same thing. For example, both have been used in reference to be "the type of resin that melts foam". Is this a typo on behalf of someone and they actually have different properties, or are they the same thing?

Polyurethane and polyester resin are two very different substances. Polyurethane resin is most often used for casting. In it's natural state it has a very low viscosity (like water) and it often sets up quickly (like working time of 4 minutes to 30 seconds). It has low oder and it's pretty expensive.

Polyester resin is the stuff that eats styrofoam. It's also the stuff that is more readily available at hardware/automotive/marine supply stores. It's super smelly, the fumes are pretty nasty for you, and the finished piece stays smelly for days.

Fiberglass
I've seen fiberglass referenced to being both resin and cloth. I am assuming what people are intending to reference is fiberglass cloth (which would then be coated with one of the various resins). Is this correct, or is actual fiberglass resin being referenced? If so, would using fiberglass resin be simpler than using fiberglass cloth with a different type of resin on top?

The terms are used interchangebly and it is confusing. "fiberglass" literally means just the cloth. However, it is frequently used to be short for "Fiberglass reinforced plastics" which is a fancy way of saying fiberglass + resin (most commonly polyester resin or epoxy resin). The term "fiberglass resin" is sometimes used as a synonym for polyester resin (that happens to be at a decent viscosity for working with fiberglass).

There's also a few products that are various combinations of resin and chopped fiberglass mixed in. These will be stronger than simple filler putties like standard bondo putty (which is basically polyester resin thickened with talcum powder), but they are also gonna be real annoying for detail work. Maybe nice for fixing boat damage, but I can't imagine it being terribly good for propwork (not that I've actually tried using it).


Joint Compound
I've seen joint compound listed as something that can be used as simply a filler, or to actually coat and strengthen an entire prop. Is this worth considering, or would it be too prone to chips and cracks?


I don't have any experience with joint compound, but I understand it is effectively a thick plaster. I don't believe it would work well for anything that needs to bend or flex, But if it just needs a hard outer shell, I suppose it would work. Personally for those applications I use bondo putty, but I have a special setup to deal with the fumes. Ideally you want to just use it outside, but in the winter when it's cold, it doesn't cure properly. (With any of these products including joint compound, you'll want to do the sanding outside while wearing a good respirator. Those tiny particles are bad for lungs.)

Lucrezea
12-30-2008, 01:27 PM
Polyurethane and polyester resin are two very different substances. Polyurethane resin is most often used for casting. In it's natural state it has a very low viscosity (like water) and it often sets up quickly (like working time of 4 minutes to 30 seconds). It has low oder and it's pretty expensive.

Polyester resin is the stuff that eats styrofoam. It's also the stuff that is more readily available at hardware/automotive/marine supply stores. It's super smelly, the fumes are pretty nasty for you, and the finished piece stays smelly for days.

This is where my main confusion has been centered. I really appreciate the explanation.

Can polyurethane resin also be used to coat an item once it's been primed to strengthen it, or is it too viscous? I ask because I've seen it referenced to being used to strengthen props, but wasn't sure it if was the poster's mixup between polyurethane and polyester.

From what I understand, epoxy resin is what most people use to coat an item to strengthen it. It seems to be the preferred alternative to other resins. Could anyone comment on this?

Also, are any of these resins strong enough to use on their own without another material? I'm sure for smaller items it's not too much of an issue, so I suppose the question is moreso in regards to larger items such as swords and the like.

The terms are used interchangebly and it is confusing. "fiberglass" literally means just the cloth. However, it is frequently used to be short for "Fiberglass reinforced plastics" which is a fancy way of saying fiberglass + resin (most commonly polyester resin or epoxy resin). The term "fiberglass resin" is sometimes used as a synonym for polyester resin (that happens to be at a decent viscosity for working with fiberglass).

There's also a few products that are various combinations of resin and chopped fiberglass mixed in. These will be stronger than simple filler putties like standard bondo putty (which is basically polyester resin thickened with talcum powder), but they are also gonna be real annoying for detail work. Maybe nice for fixing boat damage, but I can't imagine it being terribly good for propwork (not that I've actually tried using it).

Again, thank you. If I've got it correctly, then fiberglass resin can either be in reference to fiberglass coated with resin, polyester resin itself (when at the ideal viscosity for working with fiberglass) or actual resin with fiberglass mixed in; which leaves fiberglass referenced on it's own to be actual fiberglass cloth. Quite confusing, I've got to say. However, really helpful knowledge, and I'm glad I've got some clarification.

Fiberglass seems like the extreme end of things, so to speak. Not necessarily needed, but it's there if you need that extra reinforcement. Is this the case, or when items are being coated in resin, are they more often than not have fiberglass layed down first?

I don't have any experience with joint compound, but I understand it is effectively a thick plaster. I don't believe it would work well for anything that needs to bend or flex, But if it just needs a hard outer shell, I suppose it would work. Personally for those applications I use bondo putty, but I have a special setup to deal with the fumes. Ideally you want to just use it outside, but in the winter when it's cold, it doesn't cure properly. (With any of these products including joint compound, you'll want to do the sanding outside while wearing a good respirator. Those tiny particles are bad for lungs.)

I suppose if it's essentially plaster, it probably would need a coat of something to strengthen the plaster itself in order to not suffer cracks or breaks. Probably not the ideal method to coat an entire object as opposed to filling gaps and cracks.

Bondo gets referenced a lot, but its necessity seems to be alongside that of fiberglass. Something thats not really needed, but it's there if you mean business. Is this the view people have, or is bondo more commonly used than that?

ai_no_kaku
01-15-2009, 01:15 AM
This is a major help! But there is something thing we learned in my Jewelry/ Metals class at my college when we were going over casting that I think would be good to include. Polyester Resins are deadly. They give off a toxic gas while they are being worked with. And they pieces that are made with them continue to off gas with it for up to 99 years. When casting, it's best to avoid Polyester based resins at all cost. You're best bet is a plastic based resin... aka Epoxy.

Lucrezea
01-15-2009, 02:43 AM
Just to update... I've answered my own questions by purchasing a few books and doing some more research.

AVAAntares
01-17-2009, 01:47 AM
More resin questions... (aren't there always?)

I am trying to make two glowing swords, and I was brainstorming about putting a light source in the hilt and casting the blades from resin. However, in reading this thread, I have learned that to make such a large item from the polyester resin I have would be a bad idea. *pictures prop spontaneously combusting and destroying garage*

First question: Would it be feasible to cast a 30" blade from epoxy resin? I've never worked with epoxy resin at all, so I don't know how thick you can safely make a piece without risking damage from heat, or how deep it would need to be to support the length of the blade without breaking.

Second question: I don't have experience with anything but plastic molds (like paint trays) for casting small resin items. If I wanted to replicate an existing item, such as a sword or gun, would it be possible to make a mold of that item from clay and pour the resin into that? Would I need to coat the clay with something special to keep the resin from bonding to it? (I assume that any mold would need to be one-sided, to allow heat to escape during the curing process.)

Third question (not related to resin): I've searched the forums, but haven't found anything dealing with this specifically... Is there an obvious method I'm missing for making clear blades, apart from cutting them from sheet acrylic/styrene/etc.? If so, I would dearly love a link to same, and then I'll be out of your hair. ^_^

Thank you for any help or suggestions you can provide!

OneHornedMuse
02-24-2009, 09:55 PM
I'm wondering about texture/appearance/light_refraction, and weight/strength comparisons between these materials.

eg: What material would I use or method would I use to make a resin not shiny? I want it to look like wood.

Quite a few people have asked about making clear swords. The first post states there are two materials for clear plastic: polycarbonate and acrylic. Acrylic is more brittle, but more affordable. I still find this thread confusing though. Reading the wiki about acrylic (or PMMA / polymethyl methacrylate) mentions "modification of properties" such as plasticizers to improve impact resistance. I'm guessing since plasticizers are highly toxic, that they're not something that can be used outside of a professional production setting?
I wonder how heavy a sword would be in either of those materials. I wonder if there's a standard weight per volume that people could do rough calculations with.

I also wonder if either of these clear plastics can be cast (non-professionally) as opposed to carved, and how many can mix prefab sheets/blocks with cast sections without leaving any visible seams between. (I read here that acrylic can bond seamlessly with cyanoacrylite glue)
edit: "Although polycarbonate is not toxic, it needs toxic chemicals during its production phase." so I guess that leaves polycarbonate out of the casting options.

and how many of these can easily be cast without bubbles? I heard mention of a pressure pot, but is that really necessary for each of the resins here? I remember my mold-making teacher mentioning to tap our poured molds to let the bubbles rise to the top, so perhaps some materials can have the bubbles eliminated by other methods.
Pressure pots require metal molds, right? Which are expensive. Unless you can make cheap low-use metal molds... Although I'm guessing there's no affordable way to even get access to a pressure pot, huh?

Atakiri
03-03-2009, 09:48 PM
What would you recommend for making about twelve or so knives like Belphegor from Katekyo Hitman Reborn! uses?

[I couldn't find a good picture, I"m sorry]

they need to be light, and relatively easy to make and carry. Also, I want it to look like it's made of silver-like metal.

verdatum
03-06-2009, 12:11 PM
I'm wondering about texture/appearance/light_refraction, and weight/strength comparisons between these materials.

eg: What material would I use or method would I use to make a resin not shiny? I want it to look like wood.

Quite a few people have asked about making clear swords. The first post states there are two materials for clear plastic: polycarbonate and acrylic. Acrylic is more brittle, but more affordable. I still find this thread confusing though. Reading the wiki about acrylic (or PMMA / polymethyl methacrylate) mentions "modification of properties" such as plasticizers to improve impact resistance. I'm guessing since plasticizers are highly toxic, that they're not something that can be used outside of a professional production setting?
I wonder how heavy a sword would be in either of those materials. I wonder if there's a standard weight per volume that people could do rough calculations with.

I also wonder if either of these clear plastics can be cast (non-professionally) as opposed to carved, and how many can mix prefab sheets/blocks with cast sections without leaving any visible seams between. (I read here that acrylic can bond seamlessly with cyanoacrylite glue)
edit: "Although polycarbonate is not toxic, it needs toxic chemicals during its production phase." so I guess that leaves polycarbonate out of the casting options.

and how many of these can easily be cast without bubbles? I heard mention of a pressure pot, but is that really necessary for each of the resins here? I remember my mold-making teacher mentioning to tap our poured molds to let the bubbles rise to the top, so perhaps some materials can have the bubbles eliminated by other methods.
Pressure pots require metal molds, right? Which are expensive. Unless you can make cheap low-use metal molds... Although I'm guessing there's no affordable way to even get access to a pressure pot, huh?

There are a number of Polyurethane resins on the market that are marketed as having properties similar to wood. However you may find that quite a bit of the properties in the finished product are related to how either the initial sculpt or the cast piece is finished. If you polish it smooth with 2000 grit sandpaper, and the finish off with higher and higher grades of rubbing compound, it will be super glossy. If you stop at 1000 grit, it will be dull and matte.

as for density..um...I dunno, just go to your local hardware superstore any look by the screen-door stuff and you'll see the Plexiglass (acrylic) and Lexan (polycarbonate) sheets. That'll give you the best idea.

You can pick up a lot about acrylic by tracking down the "How it's Made" segment on "Acrylic Awards"

If casting, you very probably dont need polycarbonate. The only reason to use it would be if you are doing full-on combat with your sword...even then, it's cost prohibitive

Both Polycarbonate and Acrylic use nasty chemicals in the manufacturing process. I've worked with casting acrylic while making custom molded dentures. You mix together a superfine acrylic powder with monomer, which is horribly noxious, and quite toxic. However, effectively the same stuff is used in nail salons all over the world, so it's not like nuclear waste bad, I just wouldn't let anything cure indoors unless it was RIGHT next to a window with a box-fan blowing out.

At standard air-pressure, acrylic cannot be cast without thousands of airbubbles. It all has to do with viscosity and solubility of gasses and such, but yeah. Even if you tap the molds, even if you let the thing cure on a special vibrating table, it will still not be water-clear.

A pressure pot is a pretty simple device. It's like a pressure cooker (sturdy pot with a tight clamped lid), only you use a standard air compressor to build the air pressure instead of heat. You do not need any special kind of mold to use a pressure pot, it just has to be the right size to fit. Pressure pots are not entirely out of the question for the hardcore non-poor hobbist...Harbor Frieght sells one that I think about picking up from time to time. It just certainly isn't the thing you'd wanna buy just to do a single project.

For casting, polyurethane resin is probably a better bet. They are much less viscous. so air rises to the surface naturally (if you read the fine print, they usually say for best results you can use a pressure pot). the major manufacturers (Polytek, Smooth-on) both offer "water-clear" formulations. In fact, Castin' Craft resin, available at most craft stores, is also supposed to be clear.

kanancom
06-05-2009, 01:21 PM
Reviving an old thread!!

If this doesn't get me an answer I'll make my own thread

I am working on making armor for the Warrior of Light from Final Fantasy: Dissidia: http://img181.imageshack.us/img181/5899/dffartworkwarrioroflighfh7.jpg

I bought a quart of fiberglass resin at Home Depot and a 3x3' cloth. I was wondering how much resin do you think I'll be needing? I am expecting to use the resin for the breastplate, all the armor at the hips minus the belt, the greives and the gauntlets. Maybe the helm. Should I go back and get a gallon? It was $14.97 for a quart and $35.97 for a gallon so you get a lot more for your money...

Also how should I go about making up a base to put the resin on? I've read in many places papier mache is good and well as plaster bandages. This tutorial (http://www.wikihow.com/Use-a-Fiberglass-Kit) says that you can use styrofoam or carboard to build your form but you need to seal it. It says use wax paper but is there something else that can be used to seal the form? And do you need to seal papier mache before applying the fiberglass?

After the fiberglass has cured, how flexible will it be? I'm thinking about how to go about doing the breastplate because it goes all the way around the body.

Thanks

verdatum
06-06-2009, 05:09 PM
Kanancom,
Yeah, this is probably a separate topic, oh well. I really wouldn't recommend this as a first project with fiberglass. Complicated forms, lots of pieces, lots of surface area. Fiberglass is best when you genuinely need the prop to have strength. You really just want it to be smooth and able to withstand the occasional squish without killing the paint job.

You'll need a minimum of a gallon for this much armor, very probably two, and it's a HORRIBLE pain to run out of resin in the middle of a layup. You'd also need a lot more fiberglass cloth. Figure out the surface area of the piece, and multiply that by about 4. (That's figuring for 3 layers and some extra for screwups and waste from cutting out the weird pattern shapes.)

Also, that much resin will make quite a bit of chemical nastiness. You'll want to be able to leave it outside in the sun for at least a week for the chemicals to cure out before painting.

You need to seal styrofoam because the resin will eat right through it. You only need to seal cardboard because the resin will soak into it and stick. The same is true for paper mache. In either case, you can seal it with gesso (a primer paint) or white glue. Don't forget a release agent. Johnson's Floor Wax paste is nice and easy to work with.

The flexibility of fiberglass depends on the properties of the particular resin you are using, the type of cloth used, and the ratio between resin and fiberglass. But basically, then they say flexible think "when you stand on it, it will bend, not break" not, "when you flex your arm, it will give for comfort"

I'd reccomend looking into the methods using bondo putty. They give you a smothable surface without all the mess of lamination.

nobodysktr
06-07-2009, 11:08 PM
Kanancom, as to your question about the curiass (breastplate). if it goes all the way around the upper torso i would recommend designing it in such a way that it either opens on the sides or something similar. most real curiasses have buckles on either side by your hips and sort of flexes or is hinged at the part where it rests on your shoulders. try looking at real armor for design aspects pertaining to the functionality of the armor

Kitsoru
09-08-2009, 06:55 PM
(Hope this isn't too old/dead of a topic to post to c.c)

I was looking at lime green non-opaque acrylic to create a Deathscythe blade (http://www.collectiondx.com/gallery2/gallery/d/971-6/deathscythe2.jpg), but the 2'x4' cut on TAP plastics is $40 D: And even then, I'm not sure what tools I could need to use to cut the shape down further.

The reason I want to use acrylic/plexiglass is because I very much want to have the transparency in the blade, however that $40 is definitely not in my budget at this time. Is there a cheaper alternative to acrylic that I could use to the same effect?

Also, what tools would be best to work with to cut it down to the shape I need? I'm not a very handy person (read: I get terrified around bandsaws), but I do have access to shop tools (though I'd have to check with my school's access as to what I can use on an outside-bought piece of material.) I live in a downtown hirise so I don't have access to a garage, either >.>;

Thank you!

verdatum
09-11-2009, 01:06 PM
Kitsoru,

for plexiglass, I've found the prices at www.estreetplastics.com to have much better prices than tapplastics. They have tints, but not that deathscythe lime green. One thing you can do is mix up a translucent paint. They sell cheap translucent acrylic paints for painting on glass/plastic at the craft store, just mix green and yellow. rough up the plexiglass with a scotchbright pad, paint extremely thin layers, and if needed sand it with wet 1000-2000 grit sandpaper to remove any brushstrokes (or just airbrush it if you have access to one).

cutting plexiglass is both easy and hard. rough cuts can be made with a hacksaw, or jigsaw with a hacksaw blade. really, most any handsaw will work. The edge is improved if you put down some painter's tape on both surfaces of the cutting line.

The key concern with cutting acrylic sheet is heat. If friction heats it up too much, it melts and then the melted plastic just sorta globs around the tool. If using any power tools, keep them at a low setting, and don't force it. Professionally, they use wetsaws to cut it. Unfortunately, at home, most powertools you'll have access to aren't friendly with water. If you use a handsaw, you'll be alright, your arm may just hate you, depending on the thickness you buy.

Smoothing is much more important. all your cut lines should be smoothed for the best transparency effect. To do this, you start with 60-80 grit sandpaper, and slowly move all the way up to about 1000 grit if you're going to paint it.
For tinted plastic, you'll want to move to a rubbing compound. I personally like the plastic polish systems, like the Novus plastic polishes from tap plastics. You can get by with red and white polishing rouge, or automobile or CD scratch removers. The differences are just in how much elbow grease is required. It's a good activity to do in front of the TV.

Kitsoru
09-11-2009, 03:20 PM
Kitsoru,

for plexiglass, I've found the prices at www.estreetplastics.com to have much better prices than tapplastics. They have tints, but not that deathscythe lime green. One thing you can do is mix up a translucent paint. They sell cheap translucent acrylic paints for painting on glass/plastic at the craft store, just mix green and yellow. rough up the plexiglass with a scotchbright pad, paint extremely thin layers, and if needed sand it with wet 1000-2000 grit sandpaper to remove any brushstrokes (or just airbrush it if you have access to one).

cutting plexiglass is both easy and hard. rough cuts can be made with a hacksaw, or jigsaw with a hacksaw blade. really, most any handsaw will work. The edge is improved if you put down some painter's tape on both surfaces of the cutting line.

The key concern with cutting acrylic sheet is heat. If friction heats it up too much, it melts and then the melted plastic just sorta globs around the tool. If using any power tools, keep them at a low setting, and don't force it. Professionally, they use wetsaws to cut it. Unfortunately, at home, most powertools you'll have access to aren't friendly with water. If you use a handsaw, you'll be alright, your arm may just hate you, depending on the thickness you buy.

Smoothing is much more important. all your cut lines should be smoothed for the best transparency effect. To do this, you start with 60-80 grit sandpaper, and slowly move all the way up to about 1000 grit if you're going to paint it.
For tinted plastic, you'll want to move to a rubbing compound. I personally like the plastic polish systems, like the Novus plastic polishes from tap plastics. You can get by with red and white polishing rouge, or automobile or CD scratch removers. The differences are just in how much elbow grease is required. It's a good activity to do in front of the TV.

So basically, start with a normal clear pane, then cut, then sand, then paint? Sounds like that'll work. Thanks for the link!

I'll have to see what I can do as for the tools in the shops, they have a fabrication shop in the 3D objects section of the school where they sell smaller amounts of acrylic so hopefully they'll have power tools fit for those low heat speeds. ...Do you think a laser cutter would work to cut the shape I need? I might be able to get access to that.

I'll look into the polishes and paints. Thanks so much! :toothy:

verdatum
09-11-2009, 07:37 PM
Do you think a laser cutter would work to cut the shape I need? I might be able to get access to that.

According to Google, yes, laser cutters are used to cut acrylic sheet. I wouldn't know since I've never had access to a laser cutter...frankly I'm a bit jealous.

Kitsoru
09-11-2009, 11:04 PM
According to Google, yes, laser cutters are used to cut acrylic sheet. I wouldn't know since I've never had access to a laser cutter...frankly I'm a bit jealous.

I guess that's a perk of being in a school with a fabrication shop... XD; I've used it for wood before and it is a very nice cut (can give wood a bit of a burned look at the edges though, but it was cheapish wood) but you have to input the cuts you want to make in a vector program like Illustrator so it's a lot of thoughtwork/measuring work.

(I haven't the faintest idea how much they cost but for anyone that does a TON of shaping/cutting in acrylic, wood, stuff 1/4" thick and less maybe, I'd recommend them highly...)

neo_winggoddess
09-16-2009, 10:27 PM
So, I'm familiar with using resin dye to color Easy Cast Clear Casting Epoxy, but my experiences so far have been with "jewel tone" colors. My current project requires a bronze color, but I have no idea which paint to use on resin one it's cast.

Which paints work best, if you can paint resin? Does the resin piece need to be sanded or primed before the paint goes on? What kind of sealant should you use? Or are there metallic dyes out there, and, if there are, are they any good?

Phew! So many questions...I'm sorry if they've been asked before. I'm not very savvy at searching forums. :eeek:

verdatum
09-17-2009, 05:47 AM
Ooo, that one is easy. Without competition, the best method for a bronze effect in resin is bronze powder. I've seen bronze powder sold in as little as 1 oz containers at hobby shops ("allumite", was the brand I personally saw).
this video (and company) is great:
http://www.youtube.com/watch?v=TvSlN5IzDcE
This video demonstrates polyurethane resin, but the techniques apply to all resin types. For small resin pieces, you can just mix the bronze into the resin so it infuses the whole way through. For larger techniques, the video's slushcasting bronze layer will save you a bit of money on bronze powder.

As far as your other questions, resin paints better than just about any surface in existence. Primer is a good idea, but for last minute operations, it can often be skipped. No sealant is needed prior to painting, that is just to seal porous mediums like wood.

neo_winggoddess
09-17-2009, 09:51 PM
As far as your other questions, resin paints better than just about any surface in existence. Primer is a good idea, but for last minute operations, it can often be skipped. No sealant is needed prior to painting, that is just to seal porous mediums like wood.

Great! I'll probably look into mixing the powder into the resin, but it's good to know about the paint too. Coloring the resin itself before it casts always seems like the wisest choice to me, b/c I fear that paint will chip.

Thanks for all of the info! :D

hayashiox
09-19-2009, 09:16 PM
Verdatum

I dont know if your the right person to ask this but what paint is
more suitable for plexiglass outside use?

http://www.foamworks.com/more/google/google.html

Thanks

F50Grunt
01-17-2010, 11:20 PM
After browsing the thread really quickly, I was wondering if anyone knew anything about polypropylene as far as its usefulness in prop-making. I have access to a variety of machining equipment, and I know a lot more about that than I do about casting. Also, it seems to be very cheap. The props in question can be seen at http://farm5.static.flickr.com/4060/4272127401_0507c8f423_o.jpg, the "plate" (for lack of a better term) on the front of her hat and the "Rod of Remorse" in her right hand.
If anyone has a better idea for a material to use, let me know and I'll see what I can find.
Hopefully this gets read and replied to.

FanboyTous
03-20-2010, 07:39 PM
I would like to make cybernetic limbs to cosplay as Ichise from Texhnolyze. Is Epoxy Resin my best option, or do you suggest something else? I would need the end result to be smooth and look metallic.

Tyhm
04-28-2010, 01:08 PM
I'm about to embark on a translucent blade myself; using a plastic fluorescent light bulb guard
http://www.webstaurantstore.com/fluorescent-light-bulb-guard-4ft-for-t12-bulb/5664GUARD.html
and fabric dye to color the plexiglass
http://www.diyhappy.com/dyed-plexiglass
on the Inside...then squish between some big wooden furniture, cut with scissors and use cyanoacrylic/superglue to seal the cutting edge...(then probably cut again and sand). So I guess I better hope the bulb guard is plexiglass/acryllic and not polycarbonate/lexan. (which a casual search seems to indicate is the case...) Though the superglue might work anyway. And who knows if the fabric dye method would work anyway.
(PS it didn't)

If I pull this off, that might answer the Flower Petals Blade and various other Clear Blades Too Thick For Resin theories...but perhaps I am being too ambitious. ;-D

Possible recipe for dying polycarbonate (from youtube...?)
3/4 cup water, 1/4 cup acetone, half a package of RIT dye. This will apparently melt the plastic if it's overdone, so check every 20 seconds and rinse in regular water when done...
Apparently any sort of plastic can be dyed with any combination of fabric dye, solvent, and water, to varying degrees of success.

OP - do you happen to know how superglue does on polycarbonate? I'll be finding out soon either way, but I'm curious if there's a similar effect with a similar glue for Lexan...

Reenee
06-05-2010, 11:07 PM
Does anyone know where I can get a really good transparent resin in Canada? Tap Plastic doesn't ship here. :(

okageo
06-15-2010, 03:34 PM
GOoood INFO :D!!

Tyhm
06-15-2010, 06:24 PM
Does anyone know where I can get a really good transparent resin in Canada? Tap Plastic doesn't ship here. :(

Do you have a Michael's Craft Store? Most craft stores have paperweights' resins, that's what they use for making custom gems around here; or you can go with alumilite, they might ship to canada...but their clear bubbles like mad unless you have one of those vacuum chambers, I guess...I only rarely get a clear casting from it. :-(

Gaming Geek
06-30-2010, 01:43 PM
I suppose I can ask here.

I've got a project in mind that will have a large crystal as a carry prop. I've seen that you can get a resin pour that's as transparent as water.


Is there a way to get an additive to raise the index of refraction in clear plastic? I want it to be as strong a warping effect as I can get.

And as long as I'm asking questions, is there a translucent plastic pour? There's another prop that will look good if I put a light inside of it, and I have some plans with LED's. But I didn't want to be able to SEE the inside of the prop...


Hm. I guess I could buff the outside of the plastic into a snow effect for the later. But that's not really what I'm looking for.

Zabuz
08-27-2010, 01:14 PM
So...

Now people, I thought I read somewhere that since polyester resin is so awful to inhale and all that, that it wasn't even good after it had hardened. so in other words, it wouldn't be all that good to make a mask out of it since it would be so close to the face and the fumes/whatever wouldn't be allt hat good even after it had hardened.

Have I just imagined this, is it true, or was someone just rambling?

verdatum
08-27-2010, 06:17 PM
Now people, I thought I read somewhere that since polyester resin is so awful to inhale and all that, that it wasn't even good after it had hardened. so in other words, it wouldn't be all that good to make a mask out of it since it would be so close to the face and the fumes/whatever wouldn't be allt hat good even after it had hardened.

Have I just imagined this, is it true, or was someone just rambling?

All the research I've done suggests that after the resin has fully finished curing, which takes about a week, depending on thickness, UV exposure, and temperature, resin is no longer any sort of health risk.

That being said, I made a polyester resin/fiberglass mask about 2 years ago. When it's right up against your nose, you can still faintly smell that characteristic resin smell. So if making something for myself, such things wouldn't scare me, but if making a mask for someone else, I don't want them to have to put up with that odor, so I'd look into using something else, such as a polyurethane resin or epoxy resin.

Zabuz
08-28-2010, 06:12 AM
All the research I've done suggests that after the resin has fully finished curing, which takes about a week, depending on thickness, UV exposure, and temperature, resin is no longer any sort of health risk.

That being said, I made a polyester resin/fiberglass mask about 2 years ago. When it's right up against your nose, you can still faintly smell that characteristic resin smell. So if making something for myself, such things wouldn't scare me, but if making a mask for someone else, I don't want them to have to put up with that odor, so I'd look into using something else, such as a polyurethane resin or epoxy resin.

That is what I am thinking about... I'm making a mask for someone else, and am probably gonna sell it to em, so it wouldn't really be that awesome if it was unhealthy... and I have made a helmet with polyester before, so I know the smell, but since it was just me/ the only material I had, I used it.

But then I know... Thanks!
Now the biggest problem is finding Epoxy and Polyurethane in the right form... I know we got Epoxy glue, but bigger amounts... ehy, wth, I'll just have to look.
Well, as said, thanks for the answer.

Angeltx441
09-14-2010, 04:06 PM
What is the easiest way to go about making armor? I need it to be light, and fairly thin. This armor will be a full suit, sort of like a classic knight kind of thing.

What sort of plastic should I use?
What kind of adhesives?
What kinds of paint will cover that plastic?
How should I do details and such?

Tyhm
09-18-2010, 12:14 PM
If price is no object, wonderflex ftw. If you're on a budget, fiberglass. In either case, they work with pretty much any adhesive and any paint; details depends on the details, are you talking SC4 Hilde's armor with the embossed lion's heads and all? Those are kind of the opposite of battle scars, but very similar to adding gems...

OurLadyeofParis
07-29-2011, 03:43 PM
This thread has been SO helpful. A BIG round of applause to verdatum for answering so many questions. You are so informative, and I for one really appreciate it.

I have a question about molds for polyester resin. On the polyester resin jewels tutorial from HCC Cosplay (http://www.whatishcc.com/tutorials/polyesterresin.php in case anyone needs it - it's a good one!), it says that silicone molds won't be able to stand the heat generated by the curing resin. Does anyone know a good material or method for making molds for polyester resin, and hopefully not too expensive or difficult? Is silicon really not a good mold for polyester, or is it just less than ideal?

Thanks so much!!

verdatum
07-29-2011, 05:13 PM
Again, this could totally be a separate thread, oh well.

The link provided actually says that there is some reaction with the silicone causing the resin to not cure completely. Silicone does a fantastic job at standing up to heat.

I don't know about any issues with silicones inhibiting polyester resin. I've done fiberglassing with polyester resin into silicone molds (Specifically, Smooth-on's Rebound 25) with no problems. Most of my resin casting efforts involve polyurethane resin, and that stuff works wonderfully.

If I were to take a random guess, I'd postulate that it is an issue only with tin-cure silicones, and not a problem with platinum-cure silicone.

If you do find that your resin isn't fully curing, popping the mold into the oven on low is a perfectly effective solution. Just make sure whatever you use to make the parent mold is likewise able stand the heat. If you're using a plaster outer mold, heat the piece slowly, don't put it into a preheated oven. Rapid temperature changes cause plaster to crack.

OurLadyeofParis
07-31-2011, 09:47 PM
Thank you thank you thank you!!! By parent mold, you mean whatever object was covered and cast in silicone? I'm really new to mold making and casting in general (can you tell? Haha).

nighty
08-17-2011, 05:07 AM
Wow, so glad I've found this thread :) Working with plastics and stuff will be so much easier now!

As for using the silicone molds for resin casts - I've heard it might not work as well but I keep using them all the time and never had any troubles with it. You can always ask someone at the store you're buying your stuff at. We have a store specific for resins and silicons here and they can always recommend you the best silicons and stuff for the certain resins :)