question regarding semi perm

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#1

I just ordered some freekote 700 and have couple of questions…
1- do i need the sealer as well if I am using a glass as a mold?
2- does it leave residue like wax on the part? and if it does, what is the best way to clean the surface?
Thank you

#2

  1. I don’t know about the glass but performing a test will reveal a lot. TEST! TEST! TEST! :smiley:

  2. In my experience there is very little to no transfer to the part. The easiest way to remove it or any release agent is by using a medium to light polishing compound. If any does transfer it could be removed with very little effort with Meguiar’s Swirl Remover 2.0, a rag, and some hand action.

Adam

#3

Some release agents will leave streaks once it cures, you can use some mold release wax to remove the streaks. I have never use freekote, the only semi-permanent release I use is Chemlease FS One. It is good practice to use mold sealer before semi-permanent release. Sealer reduces porosity and shortens break in times.

#4

To eliminate streaks with Frekote I wipe with a clean cotton cloth right behind the paper towel used to wipe on the Frekote. Also you can buff the streaks out of Frekote. You want to start to buffer after you have let it set-up for 15 or 20 minutes. If you try and buff right away you just smear the streaks around. Most stubborn streaks appear in semis if you let a heavy application dry on the surface. Any streaks or haze that may transfer to the part can be buffed out with Meguia’s Swirl Remover 2.0 with very little effort. I always clear-coat the mold prior to layup though. I never tried to remove a streak from a part with just an epoxy surface.

Adam

#5

Thanks adam, well I did test it on a small glass first but as you mentioned it left some streaks and next i buffed it pretty good but I have not demolded it yet and that’s why i asked the question. hopefully when I demold later today it wont have any streakes.
Thanks

#6

I would recommend the sealer. Glass, aluminium, etc are relatively porous surfaces.

I use Ferrokote FS10, on a glass sheet in the lab. Apply with a damp cloth, immediately rub dry with a clean cloth. Change this clean cloth often. That works for me (no streaks)

#7

Is this similar to Chemlease 70/90 ?
I used to make flat panels made from Prepreg with a sheet of high temp release film on top of a large 1 inch thick aluminum plate but I’m considering using a sheet of half inch thick tempered glass instead to get a better surface finish. I’m considering treating the tempered glass plate with the Chemlease 70/90.
Anyone have any experience with this mold release?

#8

No experience. Read the technical data before using it.

#9

Chemlease 70-90 is for Top-Coats-Non-Class A finish.