Talk Composites - The Forum for Advanced Composites

Large 37ltr mould and questions on safely and successfully casting.

http://www.talkcomposites.com/Topic22482.aspx

By Shinobiwan - 12/27/2016 7:51:34 PM

Hi everyone.

First off thanks to everyone on here. I've read a lot of interesting threads and have learnt a lot.

I've got a project going on right now where I need to cast multiples of a large piece. The volume of the pattern is 37ltrs which is around 41kg of resin with no filler.

I've worked out the split lines on the mould and I think these will work well given the shape. All surfaces have a draft of 6 degree's and any parallel sides are on the split lines. If anyone can take a quick look over the attached image and just make sure I haven't made any glaring errors.

My question is how to cast such a large piece. I'll be using ATH filler in a quantity of 1:1 ie. 1 part ATH to 1 part mixed resin.

  • Will this allow to mix a few batches of resin and pour this in to the mould before the whole thing sets?
  • What's the maximum safe amount of resin/ATH amount to mix in one container? Any idea on pot life?
  • What's the best choice of resin? EC sell xencast P6 which I plan if suitable.
  • Can I do an in-mould coating of pattern coat primer to provide a surface that will accept paint straight out of the mould?
Thanks for any help.
By ChrisR - 1/2/2017 2:35:22 PM

1) shrinkage is variable, use as a guide but the test is normally done without reinforcement, this reduces shrinkage hugely.
2) don't know, I don't use it
3) don't know, I never use fillers
4) if using epoxy then woven roving/woven fabric (or powder bound CSM as normal CSM doesn't work with epoxy)
5) resin dependant, I'd be looking to pot a core in to stiffen and reduce cost, if using PE then 3/4 layers tops
6) don't know, I don't do it
7) loads of joining techniques to choose from, skill dependent. easiest will be butt jointed with reinforcement backing on the B-side to join together, if you get better at it then a scarf joint will be 1000% better