Molding question

[MisriahArmory]

Okay well I've been working on a master chief helmet on and off. The thing is that my helmet is a bit warped so I'm trying to make a pull with smoothcast300 and rework it with an heatgun.

http://www.aftershockcreations.com/405th/uploads/P2140030.JPG

I started a latex mold, but I doubt it will be flexible enough to make a glove mold.

So what I'd need is a cheap molding kit, silicon or rubber to make one cast out of smoothcast300. I'd prefer brushable since it's easier.

Anyone got suggestions? I heard of GI-1000 and Gel-10 which are not too expensive.

Because once my cast is clean and reworked, I'll mold it with rebound25.

Thanks for the help.

 

[MisriahArmory]

Anyone? Unless I get a reply soon, I'll buy another can of Latex sooo

 

[clonesix]

So... What is your question?

The only question that I read above is "Anyone got suggestions?"

 

[MisriahArmory]

Should I stick with Latex or does anyone know a not-too-expensive silicon/rubber molding compound.

 

[starbuckcylon]

Take a look at Smooth-on’s Rebound 25. Do a youtube search and there are some demos on how to use it.

Jim

 

[MisriahArmory]

Yeah but I'm trying to get something cheaper to make somekind of a waste mould. I cannot use plaster.

Rebound 25 is a platinium silicon which can be used over many years. I'll use that for my final cast.

Sorry if I am not clear enough :S

 

[clonesix]

What did you use for the original mold? Can you cast a resin helmet from that?

Can you block sand and Bond your existing helmet?

 

[MisriahArmory]

My helmet was made from Pepakura and Bondo. It has never been molded yet.

The warp cannot really be worked with bondo, reworking it while the plastic is hot would be the best way.

Check this for my WIP thread : Clicky

 

[LordVdr]

Try using alginate (like the kind used for lifecasting), but build it thick, and do a plaster outer shell with it. I probably don't have to tell you to be extremely careful when pulling it off of the helmet so that it doesn't tear.

Good luck.

My helmet was made from Pepakura and Bondo. It has never been molded yet.

The warp cannot really be worked with bondo, reworking it while the plastic is hot would be the best way.

Check this for my WIP thread : Clicky

 

[Chiok]

Latex is pretty stretchy in the right orientation, but you won't be able to make a one piece mould I don't think. I'd say at least two-part (right down the middle) or three parts (horizontal at the top of the visor and the down the middle for the bottom). XRobots who is making an Iron Man suit is doing a rather clever mould using latex and jayclothes to make a mould and then using plaster bandages as a mother mould. He's getting pretty good pulls from it too. The washcloth soaks up the latex and sets fairly well. If you can put some of the latex thickener into the mix, you won't have to brush on as many layers.

 

[MisriahArmory]

Should I apply the cloth everywhere or only on "key" points?

 

[XRobots]

I used cloth all over, but I put a split in most moulds so I could get them off as the cloth takes the stretch out of the latex (and stops it shrinking so much). It's a cheap way to do it, and if it all goes wrong then you can try another method. Check out my leg moulds which are two part - each with a split in... and a rigid support case which can be plaster bandage or fibreglass:

http://www.xrobots.co.uk/ironmancostume/leg09.jpg
http://www.xrobots.co.uk/ironmancostume/leg10.jpg
http://www.xrobots.co.uk/ironmancostume/leg11.jpg
http://www.xrobots.co.uk/ironmancostume/leg12.jpg

I used 10 coats of latex, then blue kitchen cloths with latex soaked in, then a couple more latex coats, then thick dish cloths (which you can see on the outer layer) with more latex.

All my parts are made that way, step by step: http://www.xrobots.co.uk/ironmancostume/ and http://www.xrobots.co.uk/ironmanhelmet/ (although the helmet was a one piece mould with no split).

 

[MisriahArmory]

Sorry for using your picture Thorsolli, but it shows it the best way...

That's how I plan to do my mother mold. So if I put cloth everywhere, I wouldn't need to make a glove mold. I could just make a "split" at the back of the mold so it's easier to release?

Do i need a release agent for the fiberglass on the latex?.

And your website have been really useful Xrobots, that's why I choose latex in the first place ^^

 

[XRobots]

I'd say that a spilt at the back would do it, but you can always cut the latex further if you have trouble getting it off - and just make the split longer etc.

I'm not sure about fibreglass on latex, but I have read that you can cast from latex moulds in Polyester resin without a release agent ( http://www.cfsnet.co.uk/acatalog/project-resinrcast.html ). Personally I'm using Jesmonite for my support jackets and finished pieces too, which is water based - if you're in the US then this is like Aqua Resin.

If you want to use polyester resin, I'd test it first by painting a thin layer of latex on a piece of plastic or something, then fibreglassing over it and checking they come apart easily enough.

 

[MisriahArmory]

Yeah I'll try this. If it don't work, I'll stick with plaster strips.

And I plan on using Smoothcast 300 for casting. I'll drop a call to smooth-on tonight probably.

 

[Big Al]

I Guess these links are to old