Question is how do you get a really good seal between the part lines along multi part moulds so that you don’t end up with a bunch of resin going between it or getting air sucked in through it while infusing?
I am thinking about tackling a 2 part mould for a symmetrical component where the part line of the mould would be down the center of the component.
I would probally mix up some resin and cabosil, and apply it to the seam prior to mold assembly. make a pastry bag to apply the bead onlong the parting line, put the mold together, clean up the excess resin and smooth it out on the mold surface, observe for any small pinholes.
wouldn’t that glue the mold halves together permanently?
Modeling clay. without having input it’s what i would do. or Silicone, smooth it and let it dry, then do your infusion.
thats why you should always wax your flanges/parting lines. this is another reason to take your time making flanges on your plug, so you have nice smooth flat parting lines/flanges. modeling clay will have a high probabiltiy of leaking under the sealant tape
I suppose clay would work, but wouldn’t I still run the risk of pulling air through the seam once it’s all under vacuum?
what process could I use to ensure nice smooth part lines that match up well?
I would need a stiff and formed flange that matches the contour of the surface I assume.
the problem is that anyone who makes plugs never spends anytime making a flange, they want to add a flang/parting line in less then a hour, which is fine if your only making a couple parts or you just dont care. I usually spend a 10-20 hours building my flanges, and the extra time is well worth it.
heres an example of a simple parting line I did:
^^ What parting line?? I only see the poster in the back!! 
looks good, what is that shiny grey material ?
aluminum filled high temp epoxy gelcoat
What properties does the Al give it? I guess you brushed this on?
it does well under many high temp cycles. transfers heat well. good for prepregs
Hojo, did you use room temp cure epoxy surface coat for the mold? How hot can that mold get inside of an oven without distorting?
Thanks.
intial cure is room temp, then udergoes a post cure ramping up to 300 degreez. the mold remains stable without the support by the plug, it is free-standing inside the oven
What brand surface coat is it, and is that a carbon fiber mold?
huntsman rengel8026 surface. yes, carbon mold
I tried an epoxy surface coat from freeman when I first started with epoxy molds. No matter what I tried I couldn’t keep the surface from being porous. Whats the right technique for applying epoxy surface coats?
degass the gelcoat for 5 minutes. I use a plastic squeegy