Resin Vs. Plastic

[mroreo123]

Something I just noticed while trying to justify the added costs of casting my pep builds directly to plastic (since from what I've read on the forums and 405th Source, it's much easier): It's actually not that much more expensive when you compare equal amounts of resin to plastic (I know both are technically resins, but you guys know what I'm talking about, right? ).

Now, before you call me crazy, here's my rationale:

* A gallon of resin goes for $30-$50 according to Google, so let's split the difference and say $40.
* Smooth-On sells the 1 Gallon Kit of Smooth-Cast 300 for $80 (rounded).

BUT!

The Smooth-On kits actually come with 2 gallons of product! 1 gallon of part A, 1 gallon of part B. Just look in the pictures they have:

So doubling the cost of resin to compare apples to apples, we get $80 of resin vs. $80 of plastic. Even with price fluctuations depending on your area, what stores you're shopping at, shipping costs, etc., it can't be THAT great a difference in price, can it? At least, not as big a difference as we originally thought?

And I also read on Smooth-On's site that you can use fiberglass with their plastic (they used Smooth-Cast 325 as a specific example), you can still get the strength of glass with the ease of use of plastic together with a lower overall weight than plastic alone.

Does anyone with experience using both have any additional information to tip the scales one way or another?

 

[Yodajammies]

I've never seen resin over about 20$/gal. But then you do have to include the cost of glass matt.

I'd recommend going to glass/resin route until you know what you're doing.

 

[Das Brutus]

I really need to write down all I see here on the 405th... but there is a page here somewhere where the member uses smooth on to coat the inside of the helmet, bypassing the resin/fiberglass of the interior stage. He claims it also helps with the sanding... possibly cutting down the need of or the amount of bondo. I'm still in the build stage, but it's what I'm giong to try on my torso.

Here it is:
http://405th.com/forums/index.php?showtopic=15472 by Ruze789

found it... saved it in my i.e. favorites!

 

[timonemycat]

Home Depot sells resin for 33$ a gallon

How could you do plastic on the torso, doesnt it need to be a bowl shape to slosh it all around in there?

 

[Ral Partha]

I really need to write down all I see here on the 405th... but there is a vid here somewhere where the member uses smooth on to coat the inside of the helmet, bypassing the resin/fiberglass of the interior stage. He claims it also helps with the sanding... possibly cutting down the need of or the amount of bondo. I'm still in the build stage, but it's what I'm giong to try on my torso.

Try this thread. It's not the video thread but it's a tutorial on using casting resin to reinforce armor instead of fiberglass and resin. I haven't tried this myself but it seems to be a cleaner (hence preferred) way to doing it.

 

[mroreo123]

I've never seen resin over about 20$/gal. But then you do have to include the cost of glass matt.

I'd recommend going to glass/resin route until you know what you're doing.

Where did you see this price? I can't remember how much Walmart is selling a gallon for, but their quart size is $10 or $11 if I recall, which should make a gallon at about $40 tops (should be a little less for the bulk discount, but 1/2 price?)

 

[Das Brutus]

How could you do plastic on the torso, doesnt it need to be a bowl shape to slosh it all around in there?
[/quote]

and I quote ADAM:
QUOTE(Adam @ Mar 26 2009, 08:29 PM)
If you want to grease up a frying pan so you can cook some fried eggs, how do you get the grease to coat the entire pan? Do you:

1. fill the pan to the brim with oil?
2. Put a table spoon of oil and slush it around until it coats the pan with a thin coat of oil.

I had the same question... torso casting... Slush the interior... after resining the exterior...

 

[GeneralMayhem]

Actually, this is how I've been doing my build. I assemble my pepakura pieces with the flaps on the outside, to leave a clean inner surface. I then coat the inside of the pepakura "mold" with Vaseline, making sure that any corners that might leak have been filled in with Aleen's Tacky Glue. I then do a "slush" cast of the part with Por-A-Kast II two part urethane resin (I prefer Por-A-Kast II because it doesn't need to be degassed like most of Smooth-on's resins do). I make sure that the resin reaches every corner of the mold, and watch for any bubbles that need to be popped before the resin sets. When I've built up enough layers of resin to make it thick enough to be sanded or smoothed to a final shape, I back the resin with a layer of 2 part expanding urethane foam, to add stability to the part so that it can be handled without being so fragile. When everything has set for about a day, I simply peel off the paper mold, and start my final detailing.

 

[mroreo123]

Actually, this is how I've been doing my build. I assemble my pepakura pieces with the flaps on the outside, to leave a clean inner surface. I then coat the inside of the pepakura "mold" with Vaseline, making sure that any corners that might leak have been filled in with Aleen's Tacky Glue. I then do a "slush" cast of the part with Por-A-Kast II two part urethane resin (I prefer Por-A-Kast II because it doesn't need to be degassed like most of Smooth-on's resins do). I make sure that the resin reaches every corner of the mold, and watch for any bubbles that need to be popped before the resin sets. When I've built up enough layers of resin to make it thick enough to be sanded or smoothed to a final shape, I back the resin with a layer of 2 part expanding urethane foam, to add stability to the part so that it can be handled without being so fragile. When everything has set for about a day, I simply peel off the paper mold, and start my final detailing.

That sounds like a really nice workflow. Do you have any pics of your results from this method?

 

[GeneralMayhem]

Not at the moment, as I dropped my camera and trashed the lens. I plan to do a sequence tutorial when I can get a replacement. My first "proof of concept" piece was my hand plate. Afterward, I scrapped my original helmet pep in favor of one of the more high resolution models because i realized how much detail I could retain by using this method.

 

[MECHA MATT]

Well it seems that using plastic would be better than resin even with the few extra $$$ it seems more durable and not as likely to crack or shatter good luck getting it on though doesnt it take forever to cure or something like that?

 

[mroreo123]

Well it seems that using plastic would be better than resin even with the few extra $$$ it seems more durable and not as likely to crack or shatter good luck getting it on though doesnt it take forever to cure or something like that?

From all the videos I've seen, it only takes a few minutes for the plastic that we use on the forums here. But yes, there are types that take much longer to cure.

 

[treduder]

imo the real saving is the time saved and the mess u can avoid.. resin is annoying.. toxic... blegh. with the plastic casting way you only have to use a lil resin on the outside to reinforce, etc

Actually, this is how I've been doing my build. I assemble my pepakura pieces with the flaps on the outside, to leave a clean inner surface. I then coat the inside of the pepakura "mold" with Vaseline, making sure that any corners that might leak have been filled in with Aleen's Tacky Glue. I then do a "slush" cast of the part with Por-A-Kast II two part urethane resin (I prefer Por-A-Kast II because it doesn't need to be degassed like most of Smooth-on's resins do). I make sure that the resin reaches every corner of the mold, and watch for any bubbles that need to be popped before the resin sets. When I've built up enough layers of resin to make it thick enough to be sanded or smoothed to a final shape, I back the resin with a layer of 2 part expanding urethane foam, to add stability to the part so that it can be handled without being so fragile. When everything has set for about a day, I simply peel off the paper mold, and start my final detailing.

hay this sounds like a pretty good way too.. how much is that foam youre using btw, and where do you get it??

 

[GeneralMayhem]

ATM I'm using Smooth-on's FOAM-IT! 8. Before I ran out of my supply of it however, I was using Alumilite's 610 Foam, which is nearly identical in consistancy, but easier to work with because of the dispensing bottle it comes in. I actually bought them both around the same time so that I could compare the products, but ended up using the Alumilite more often simply because of how they package it. A 32 oz. kit was $25.

 

[MECHA MATT]

good my bro used one that took 2 days to cure pretty crazy huh so how long will yours take

 

[GeneralMayhem]

It seems to reach full hardness in about half an hour, but I tend to leave my castings overnight, just to make sure I don't waste my invested time and materials on a casting that's not ready to be handled yet.