Ski Builders Forum

So six months and about $4000 into it and I have pair of skis to admire. Problem is that I am having the darndest time removing the clear packing tape from the bases that I applied to protect from epoxy etc.

I have trouble shot everything thus far but now I am stumped. Short of meticulously chisling piece by piece with little screw driver I have tried base cleaner (to maybe soften adhesive, actually seemed to gel to base more)
belt sander (actually melted tape into base somewhat) wire brush etc.

I think I read somewhere about specific brands of tape to use? maybe green painters tape instead?

any info would be greatly appreciated! I am going to chisel in the meanwhile...

Hey AK,
I had a simular problem with the first skis. We peeled as much as we could then elbow grease and solvent to loosen the glue. Finally it came off and have not noticed any problems from using the solvent, yet. However, I am going to check on the skis today after reading a post on skis loosing camber do to storage and heat (summer temps). Good luck.
ra

Tape is a pain. I stopped using it and found only about 7-8% of the base surface would get epoxy on it. This is never a problem as the Montana tuning machine just grinds it off during the base flattening. You can also rub paste wax on the base prior to layup as a type of mold release; just be very careful not to contaminate the pieces to be glued. Good luck.

We used to use tape, but it is more trouble than it is worth. The little bit of epoxy that gets on the base comes off after a base grind. Tape also doesn't work in a heated press.

If you still want to use tape, use good quality Scotch brand packing tape. It is clear and thicker than the cheap stuff from office max.

-kelvin

I will second the above comments about cheap tape. Stay away from it! I wasted a huge amount of time peeling the stuff off my skis. The latest method I have used though seems to work pretty well, as long as you can keep the other materials from getting contaminated:

What I do is coat the bottom of the ski in Crisco (shortening for cooking), and then lay it down on plastic wrap. The Crisco sort of sticks to the plastic wrap, and everything comes apart pretty nicely. It also keeps the epoxy from bonding well to the bottom of the base. Then, the grinder takes away any leftovers.

Granted I haven't attempted building skis yet, but what about applying a coat of wax on the base before pressing. Wouldn't that prevent any epoxy from sticking to the base?

Could be wrong...but just throwing it out there

i think about that option, to... someone ever try it...to share the experience???

it could work. in the composite industry they also use wax to keep some laminates from sticking to the molds. normal ski wax would work, i suppose. sometimes they use a special releasing agent wax. this wax has some alcohol in it i guess to keep it smooth and "liquid".

but you had to work very careful with the wax...otherwise you may get some places where the epoxy doesn`t bond in areas where it should.

plywood wrote:sometimes they use a special releasing agent wax. this wax has some alcohol in it i guess to keep it smooth and "liquid".

Maybe WD40 would be a good releasing agent, it's primarily a lubricant (as most of you will know). WD40 also uses a thinning agent (like alcohol), so you should be able to create a really thin layer on your mold and base (But it might also affect your base ).

I have not tried it, so I'm not saying it will work. I will also be using a release agent for my next pair. I'm still trying to decide between spray skiwax, WD 40 or some other kind of household grease/lube.

Ofcourse you have to be carefull to keep your glueing surfaces clean when using a release agent. But it will make the skibuilding proces easier.

For high volume production work with molds, PVA (Polyvinyl Alcohol) is used. Basically you spray it on, and it forms a water soluble film that allows resin to release.

For lower volume and one off work, we would use mold release wax. I can't remember the exact brand, but anyplace that sells fiberglass probably stocks a release wax. Carnuba waxes should work fine, even a cheap car wax will probably work to release skis. I would really stay away from the WD-40 and grease here. Just get a good past wax.

There are also some high temp tapes that I have used with epoxy before. 3m makes a green tape, feels more like a plastic then masking tape. Automotive paint supply stores would sell this. IIRC it is Fineline masking tape.


This info comes from working for 5 years at a composite boat company, and building three canoes from a mold, plus many other odds and ends.

Yikes! I'd sure stay away from WD-40. It's a 'penetrating lubricant' which means that it is easily drawn by capillary action into all of the tight voids like the joint between the base material and the metal edge, then onto the bond surface of the base material itself. That would spell certain disaster for the ski.

Here's what I have found to work really well. After the edges have been glued to the base, I lay the assembly on the work table, ski base facing up. Then I mask off the metal edge plus about 1/8th inch of the base material adjacent to the metal edge (total masked area is about 1/4 inch of the outer border of the base assembly). Then I spray a universal mold release on the remaining exposed base surface and let it dry. After the mold release has dried, I remove the masking tape and then tape the entire base with clear packing tape. The packing tape sticks to the released base material just enough to stay put, but comes off in one large easy peel after pressing. Masking off the outer edge of the base assembly before spraying mold release keeps the mold release from getting into the metal edge/base material junction and still allows for a thin border for the packing tape to bond well to, thus preventing resin seepage through the metal edge/base material joint during pressing.

The spray-on mold release can be purchased through just about any fiberglass supplier for 8 to 10 dollars a can.

G-man

G-man wrote:Yikes! I'd sure stay away from WD-40. It's a 'penetrating lubricant' which means that it is easily drawn by capillary action into all of the tight voids like the joint between the base material and the metal edge, then onto the bond surface of the base material itself. That would spell certain disaster for the ski.

G-man

Yeah, I overlooked the capillary action. Capillary action will also be an issue with an alcohol/wax release agent, because of the fluidity of the stuff.

I will probably prep the base with a proper release agent before I route the base, that way the release agent stays clear of the edges and glueing surface. Thanks for the advice!