A sticky glassing problem!

[Allan Bennett]

Update:

The acetone wasn't such a quick fix as might have been inferred from my previous post; It's taken several cycles of wiping with acetone and then leaving to dry for a day, and there's still a slightly sticky bit on one wing tip. But I've got to the point where I'm rubbing it all down now.

There's a couple of spots that need remedial work (slitting blisters and sticking them down flat with cyano) before applying Halfords' grey primer, but I don't see that I'll need to do an overall re-coat with resin. After rubbing the primer down, and applying more coats if necessary and rubbing down again, I normally go straight to my base colour using Lifecolor water-based acrylics applied by airbrush. I've never had a problem with masking tape lifting it. After all colours are complete I go over the lot with Humbrol clear varnish -- matt, satin, or gloss as appropriate -- applied from a rattle can or by airbrush.

[MikeQ]

Quick question ... is SP113 still available? Used it in the past but ripmax don't seem to list it and coming up short on google.

dont like the EzeCote/PloyC stuff as in my experience, even if left a long time (months) to harden it goes kind of rubbery and clogs the paper when wet sanding with Wet&Dry.

Cheers

Mike

[Martin McIntosh]

I buy my resin from ABL Resin and Glass, Sandbach. You need the multi purpose type, not general purpose. Available in 1.5l. It should work out cheaper than model dealer stuff and is a proper professional product.

[Michael Barclay]

Epoxy resin not curing properly is invariably down to poor mixing. The resin will pause curing at low temperatures but unlike polyester resin will commence curing again when temerature rises.

[flight1]

If the epoxy hasn't gone off then it never will , the sticky bits is the epoxy that wasn't mixed properly and having this the laminate will never be at full strength. put in hot box for a week wipe off sticky with isopropyl alcohol (proper solvent for epoxy, be carefull) and apply flow cote over top or grind off completely and re do ()

With epoxy always weigh accurately to the specified ratio as per epoxy type used and mix thoroughly and use in temperatures reater than 16deg cel for good results

My preferred laminating resin at the moment is from here **LINK** and there light cloth for skinning is good tight weave see here **LINK**

[CARPERFECT]

if you are anywhere near a local car body repair shop. you could ask them to put it in their spay booth and just leave it in the booth for as long as they will let you, the bigger the body shop the better, as the oven will be on more.

[John Stainforth]

For glassing my Supermarine S6b modeI, I used L285 epoxy resin and hardener, available from Fighteraces, with absolutely no stickiness problems. The resin and hardener are mixed  carefully in the ratio 2.5:1 by weight.

The only stickiness I find occasionally is in the thin remnants of resin on the walls of the mixing pot. It seems that when mixing there is a stagnant fluid boundary layer next to the pot wall that does not get properly stirred with the rest of the mixture. This is not a problem, because I always decant the mixed resin into a broad plastic dish to avoid a thermal runaway in the mixing pot, which has too small a fluid surface area to volume ratio to allow the heat of reaction to get out of the mixture fast enough. This decanting has the extra benefit of leaving the poorly mixed resin on the pot surface behind in the pot.

Edited By John Stainforth on 07/10/2019 20:35:35

Edited By John Stainforth on 07/10/2019 20:37:21