The Imperial Shipyards

Imperial Creative Engineering => Resources and References => Topic started by: DocOutlands on August 06, 2009, 06:33:16 AM

Title: Ask a Caster! Got a problem? Get help here!
Post by: DocOutlands on August 06, 2009, 06:33:16 AM
Just a thought I had, since I have a problem.   ;D
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: DocOutlands on August 06, 2009, 06:37:37 AM
I have a mold of a head that consistently has an air bubble in the same spot every cast.  Does this indicate a need to redo the mold using a different angle on the head?  Would putting the mold into a food-sealer marinating box and then "sucking a vacuum" on it work?
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: Clonehead on August 08, 2009, 06:13:10 AM
Doc, if you want to save that mold you may be able to use one of two or three methods. One is the super squeeZe method where you squeeE the air out before you pour and release as material fills the void. You can just pour enough of the part to get material to the problem area, squeeze it a bit to force material into the problem area, let it set up some and then pour the rest.
Or the most effective solution for me is to cut a vertical slit in the mold from the outer edge of the problem area up to the top of the mold. This will allow you to spread the mold in that area as you pour and will give the air bubble an avenue of escape.
What part is it so I can better understand where the air is getting trapped?
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: DocOutlands on August 08, 2009, 06:25:52 AM
I think approach #1 solved my problem.  I was consistently getting an air-bubble at the top of one particular head in the same spot.  I've changed my squeeze tactics and I think I may have it licked.  I've gotten two in a row without the bubble.

Thanks!
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: spudafett on October 08, 2009, 02:20:29 PM
mold release agent...

is there a cheap home made alternative?

I read that petrolium jelly, ie- Vasoline, works well. 

I also read somewhere that you can mix vasoline with water untill it is a liquid and use it in a spray bottle... if so that would be my best bet I think...

I'm probably going to start on some molds tonight!  wish me luck
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: DocOutlands on October 08, 2009, 10:22:57 PM
I haven't yet moved into the world of release agents. 
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: Clonehead on October 09, 2009, 05:04:34 AM
I read along time ago that vasoline would work for this but don't know if it will work for the products we are using.
It would be an experiment.
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: spudafett on October 09, 2009, 10:43:43 AM
well i guess I'll try using vasoline on one of the two part molds I did and not use it on the other and see what happens...
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: narceron on October 10, 2009, 08:47:24 AM
While I don't have any experience with this resin casting, I've been green stuff molding for years, we used oil, vegetable, I think, to keep things from sticking to those molds and it was GS on GS, so it had to work, :)

wait, great googly moogly, I bet I can use the resin on my GS molds. . .Woot!
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: spudafett on October 10, 2009, 09:47:42 AM
lol of course you can use resin on that... heck I was using clay to help form my two part molds and the clay holds shape pretty well too so I think you could even use clay to make temporary molds....

I might try that...
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: narceron on October 10, 2009, 11:40:51 AM
I have so many skulls and gibble from my GW days, could be awesome, :)
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: B.R. Steel on October 20, 2009, 05:48:52 PM
I've got a question.  Does anyone ever have a problem with their dremel melting the plastic that they're trying to "dremel away"?  I have a fairly old dremel rated for 5,000 to 30,000 rpm.  Is even the slowest speed here too fast?
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: Clonehead on October 20, 2009, 06:16:33 PM
for me it is, b.r., although I have never tried using it to cut resin before. the friction caused even by that slow speed will create enough heat to make plastic or styrene melt. I suggest you try a good cordless drill to chuck your cutting, sanding, or grinding wheels and bits into and work with it. That way, you can regulate the speed lower, at a pace that works for the material that you are working on.
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: spudafett on October 21, 2009, 10:01:26 AM
It takes some getting used to, just work in short and quick bits.  Like tap the surface your sanding, then let it cool, tap it again for a second more, and then let it cool.  Don't just hack into it for a good minute or so and expect it to sand right...

I've done that in the past and it melted the plastic and wrapped around the sanding drum... and I've also had molten plastic thrown in my face...

Just try practicing on some scrap parts untill you get the feel for it.  Dremelling is realy an art more than it is a technique....  if that makes sense... you realy have to work at it untill you get the feel for it.

go slow, work in short bursts, and you should be good.

Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: B.R. Steel on October 22, 2009, 04:38:06 PM
Thanks for the advice guys.  Although my cordless drill would be a bit awkward for most things it might be just what I need for some projects.  Looks like for other things, I just need to learn how to work the dremel better. 

Thanks again!
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: Clone_General_1977 on October 24, 2009, 07:27:22 PM
I have a problem. When I try and upload pics from my camera, it says that the size is too large in kb. How do I fix this?
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: spudafett on October 24, 2009, 08:16:59 PM
us a program on your computer and resize the immages.  OR post the images using a third party online hosting service like photo-bucket, flikr or deviantart....

btw, this thread is for questions on Molding and Casting parts, there is an IT problem help forum at the bottom of all the other forums for these types of questions... good luck.
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: Clone_General_1977 on October 24, 2009, 08:36:08 PM
Oh, I didn't know. I'm new here.
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: spudafett on October 24, 2009, 08:45:33 PM
It's all good ;)   Just trying to help.
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: poucher on February 04, 2010, 12:48:59 PM
heah how can i do clone wars face 2 clone trooper
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: narceron on February 06, 2010, 09:54:47 AM
It's all good ;)   Just trying to help.


My computer makes a loud whirling noise while I'm casting....
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: Clonehead on February 06, 2010, 12:08:19 PM
It's all good ;)   Just trying to help.


My computer makes a loud whirling noise while I'm casting....
I had that problem once, Simon. When I opened up the bottom of my pc, I found that a bunch of resin shavings had gotten sucked into the processor's cooling fan and jammed it up.
  No more sitting the laptop on the floor after that.
Title: Re: Ask a Caster! Got a problem? Get help here!
Post by: poucher on March 30, 2010, 11:26:25 PM
hi ineed to no how to upload stuff