How do you infuse using a multi piece mold?

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#1

OK so here is a Q, how do you infuse a part using a multi piece mold that has a flange along the part line and bolts that could all serve as points of leaks where air could be sucked in?

I have thought about putting sealent tape along the length of the flange on the outside to bridge the two sides to prevent leaks and also thougth about putting a layer of pva on the joining faces of the flange on the inside to kind of make a gasket. I am imagining using a semi perm release on the rest of the mold. Any thoghts?

Would it be possible to use c clamps instead of bolts to hold the parting flange together?

#2

Stiff flange + sealant = no problem.

#3

would you recommend the sealant be put on the joining faces of the flanges or along the edge that they meet on the outer side?

If the sealant was placed on the joining face then that would create an extra gap and the mold sides woudl not be flush together?

Could you please clarify? Thanks.

#4

if you strech the sealant tape so it becomes very thin, there should be no problem with gaps between the two pieces. :slight_smile:

#5

On two peice molds I use bagging tape but I also use Scotch tape to seal the gap.

#6

I might give that a shot.thanks.

#7

How is it that you use scotch tape, I don’t really understand?

#8

pics please.

Mark44

#9

Don’t use bagging tape to seal the joint! :rolleyes: That will leave a gap.
Use liquid sealant, and make sure to go around the bolt holes. If you use clear or gel coat before laying up, that will seal it even better and further reduce possibility of leaks.
With properly made molds, we can pull 28" just by bolting the mold halves together, no sealant. The sealant is just a precautionary measure.

#10

Good info thanks, I will not be using gel coat but epoxy surface coat. Will that be good too?

I’m not sure what the liquid sealant is that you are talking about, could you please elaborate?

Thanks.

#11

anyone with any ideas what this liquid sealant is?

#12

Dude, it’s really just caulking. Find one that’s compatible with your molds and materials.

#13

oh hahah that’s easy enough.