breaking in a mould

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#1

hi ,

after polishing a mould how would you guys go about breaking a mould in using

  1. Paste wax

  2. semi - Permanant release agent?

thanks in advance:)
ben

#2

Here is good article about seasoning a mold when using polyester based products: Why Molds Stick
Epoxy tooling can be a little different. Does your mold have an epoxy, VE, or PE based surface? Is the layup performed with epoxy, VE, or PE?

#3

polyester. cheers

#4

do people use PVA with semi permanents thou?

ben

#5

I don’t use PVA with a semi. I use the semi sealer and the release You should test your system first though.

#6

For breaking in a mould, a semi perm is not advisable. Also, the PVA will probably bead away from the semiperm.

For breaking in a polyester mould, just use paste wax and PVA. After a couple of pulls, you can revert to just paste wax or a semi-perm.

#7

I never even noticed a break-in period with a semi-perm…at least with Frekote FMS sealer and 770-nc release. I use them straight off and have great success if the layup resin/mold surface/in mold coating is compatible.

If you start with wax and are going to convert to a semi-perm then you must completely remove the wax from the mold surface. Polishing compounds work well for doing this.

#8

Using semi-permanent release to break in a VE/PE mould is fine. But prior to apply the sealer/release you should first give it a good post cure, Clean the mould surface twice with mould cleaner, then apply 3 coats sealer to a new mould, followed by several coats of release. After first release apply atleast one more coat of release.