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SUP KIT - Epoxy stick to plastic?
2nd post on this - I posted earlier and it is now removed. Is this forum edited or is there an approval process?
Just got my Kaholo 14 kit.
Questions:
1) Does eboxy stick to plastic? Directions state laying down plastic sheeting - others report using wax paper before glueing joints. If I lay the panels down on the plastic and glue drips through wont the plastic bond to the extra epoxy?
2) Directions state puting fiberlass strip over the joint that was just glued. Do I wait for the joint to dry before epoxying the glass? Or can this be done all at the same time.
3) Directions state puting a board over a glued joint with weights on top. I cannot see how the weights or board will not be glued to the joint! How do you prevent this?
Tx!
4 replies:
RE: SUP KIT - Epoxy stick to plastic?
You can also try parchment and freezer paper. Both are a little tougher than wax paper. Tracing paper also works to keep the mess down but it will stick and sanding it off is difficult.
RE: SUP KIT - Epoxy stick to plastic?
Epoxy and polyester resin are basically casting agents. When you apply them to foam, they soak in a little, and then form a casting mold that includes a small amount of foam. When you apply them to solids, they do not really bond; they more or less cast themselves to the surface. The rougher the surface, the better the adhesion. So, roughing with 50 grit sandpaper helps adhesion a lot.
RE: SUP KIT - Epoxy stick to plastic?
» Submitted by Laszlo - Sun, 10/14/12 » 2:28 PM
There is a moderator but that's only to get rid of spam and inappropriate language. If you were asking in the same tone that you are now, no one would have deliberately deleted your post. How long ago was it? Maybe it just rolled off the bottom of the page.
Anyway, epoxy does not bond to smooth polyethylene or to inert hydrocarbons (the wax on wax paper is a crystallized paraffin). So you can use strips of either material to separate surfaces that you don't want bonded.
I never use wax paper for this purpose because if the epoxy goes exothermic, the heat can make the wax melt and flow into the epoxy, ruining the joint.
By all means put the glass on immediately after gluing the joint. It's more convenient, saves time and gives a better bond. Just remember to add enough unthickened epoxy to wet out the glass.
A layer of polyethylene between the board and the joint will prevent the board from bonding to the joint. I like using 4mm painters' dropcloth from the hardware store. You get a lot in a roll, it's transparent so you can see what the joint's up to underneath it and you can peel away the cured epoxy & reuse the poly.
Have fun,
Laszlo