Teflon tape for release agent on mandrel/male core

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#1

I’ve been looking into the aquapour core materials as such I’m digging further into the best practices for release. The manufacturer suggests using teflon release tape. Anyone know where this can be sourced? Also wider tape would be most convenient and practical.

Any caution or advice using it?

My plan is to have a core material onto which I will lay prepreg then bag and cure. The internal core will be removed and the imperfect outer surface will have a peel ply texture to allow for further processing.

#2

Plumbers tape is teflon tape, I think - is that what they mean? Of is there a teflon tape that is actually sticky on one side?

#3

I bought a few rolls years back for a special application from Revchem
http://revchem.com/

it is flexible and nothing will stick to it

P/N inside the roll is #7037200016

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#4

Geckosub, yes typically.

#5

Skivved teflon. Mcmaster and C.S.Hyde has it.

However…the problem is, if you use it as a release, the resin will get locked into the areas between the pieces of tape. You want a good polished surface only for a tube mold. Or one with a slight taper. Else, when you cure the resin, if the cured material sees ANY roughness, it will mechanically lock onto the mandrel!!!
Only if you maybe, soak the part in LN2, and have the mandrel shrink enough, then you can pull the part off.
Even now, I use ONLY liquid release (frekot 700 and 55), and normally stick the whole thing into the freezer to shrink the aluminum a bit.
Have a scratch on the tube? It’s HELL to pull off!! because the part takes on the scratch void, and then you have to drag out this resin line over the entire surface!

You can use it as a normal mold release…because you are lifting the part UP off the surface.

#6

THanks riff42, the mandrel will be soluble so the locking in will be less of a concern. The manufacturer recommends a teflon release to be wrapped around the mandrel. I would rather a coating over the surface but not sure what would work…since the mandrel is water soluble(i’ve thought about just brushing on a layer of epoxy and letting it cure). The point of the coating/teflon barrier is to provide a barrier between the textured(plaster like consistency) of the cured mandrel and the layup.

By the look of things the teflon method seems like a rather expensive way to go compared to perhaps just brushing on a thin coat of epoxy and letting it cure. I’m not actually going to be too worried about the finish on the mandrel side since it’s internal. I suppose I just don’t want excess resin getting used up from the prepreg that the mandrel will be wrapped with.