Ski Builders Forum

I've been handling base material, edges etc with my bare hands and recently heard that oils from your skin will affect epoxy performance. I've not a noticed a problem before, but maybe this is something I need to considor?

Does anyone here clean their materials before lay-up, and of so what do you use? I'm assuming some kind of light solvent?

Apologies if this is a repeat, I did a search but couldn't find anything although I'm sure i once saw something related.

We wipe everything down with acetone, it will take off just about anything. When you wipe it down, don't scrub back and forth, that just moves stuff around. Try to do it in long continues wipes to actually wipe the stuff off.

OK. And i suppose give it some time to compeltely devolatize before getting it wet?

Thank you.

My bad, I found this:

http://www.skibuilders.com/phpBB2/viewt ... ne&start=0

I'll leave it up for a few days in case anyone gives a hoot.

You can also consider isopropyl alcohol. MEK and acetone are a bit potent - acetone is good for getting epoxy into the bloodstream ... I have to upgrade my gloves too. I think there are a few more posts on this subject - searching is a bit hit and miss sometimes

denatured alchohol and mineral spirits/paint thinner have been mentioned as well.

Yeah if you're not cleaning off epoxy, just oils I'd say denatured alcohol is the way to go.

acetone is bad. It damages the plastic on a molecular level.

I clean everything with air, mineral spirits, and flame.

Can I add another related question?

What do people do about surface rust on edges before layup. I could sandblast them again but difficult to fit the 2m piece in the blasting chamber. I think I've seen people sand them with a dremel tool? Then a good air spray and wipe down with alcohol before tacking to bases?

And any way to help prevent the sand blasted edges rusting with time (I have them in a spare bedroom and they seem to be picking up rust). I suppose keeping them in a sealed box would be the best way?

falls wrote:...
What do people do about surface rust on edges before layup...

I use a brass wire wheel in a drill motor to knock off the soot created by the annealing process (used to make tight bends in steel edges.)

This tool will easily clean off any rust. A light touch is required or else you'll grind off the primer and the sandblasted texture too.

Best way to store metal that is prone to rust is in VCI plastic bag, or failing that in VCI paper. It releases a chemical as it breathes that helps prevent rust.

An Australian supplier is here http://www.australianinhibitor.com.au/page/1/home.html. I vouch for these guys, we used hundreds of thousands of dollars worth of their stuff to send stuff like machined cranks and camshafts overseas when I worked for GM, never had a single rust issue. We also put desiccant bags (silica gel) in them before sealing to absorb the moisture.

I'm not sure if he does small scale stuff, but it won't hurt to ask. If no good, just put it in a plain plastic bag or sealed box with silica gel. If you leave it open to the air, the silica gel is useless.

Nice one Shif

falls wrote: And any way to help prevent the sand blasted edges rusting with time (I have them in a spare bedroom and they seem to be picking up rust). I suppose keeping them in a sealed box would be the best way?

You could always spray them down with WD40 while they're in storage, then just clean them before layup. I put WD40 on lots of bare metal things in my shop to prevent rust.

thanks all

You have to be careful with WD40, it can soak in to the metal which may have an effect on bonding. I know it's not generally a good idea for protecting bare metal on cars before painting.