Sealing wood

I use a non-blushing, low-viscosity epoxy with a slow hardener to ensure absorbtion into the wood grain.
West System, MAS are 2 of the brand names I've had good results from.

 

west system will blush - i use alot of west system...

that blush,it must be removed with soap and water - acetone and sanding/grinding will not remove it...

a good habit to get into:
in cooler temps,warm the epoxy with work lights,this will "thin it ",and make pumping it out of the container pumps much easier...

another word to the wise:

do not discard any containers of mixed expoy into a trash can,it can and will set the trash on fire,when it starts to kick...i use 5g buckets with some water in them,i chuck the containers in there...

 

Correct me if I'm wrong kreepa, but isn't the hardener used responsible for the blush in West Systems?
I used West System epoxy and 207 hardener to finish a single skin of 4 oz cloth on a wood canoe repair.
It didn't blush, still we sanded with 220 and then polyurethaned for u-v protection.

                                                                :-?

 

amine blush is a result of the mix kicking - not sure what you're saying ??

i've never had a west system mix not blush - it will feel slippery and waxy...

i know certain brands of epoxy will not blush,i'm not aware of which - i don't use them at my shop

 

Talked to my neighbor this morning while walking dogs,
he still had the containers in his garage. West System 105 epoxy and 207 hardener.
Apparently it's a special purpose mix for clearcoating, produces minimal blush.
The fact that we wet sanded with 220 must have dealt with any minor waxiness that did occur.

 

that changes things dramatically !! that information is correct,concerning that hardner


aimine blush needs to be removed by using soap and water - sanding,without washing with sopa and water is not a good idea,it can and will cause a contamination...

220g - wet sanding ?? that's a pretty coarse grit for wet sanding ?

 

We went with 220 over the original instructions.

Had to repair the strip built canoe in order to sell it.
It's not that we knew what we were doing,
just following the how-to found on line...

http://www.westsystem.com/ss/varnish-over-epoxy/

 

I have and continue to use http://boatbuildercentral.com/proddetail.php?prod=E_kit_3gal#.UOh7PlFgWp0 with the slow hardener.  I never have any blush.  I still wipe it down since it only takes seconds but it has never been needed. I never feel that oily greasy residue or see anything like I have gotten with other epoxies on occasion. If I recall correctly denatured alcohol will dissolve blush as well. I actually bought some just to try it out since it dries faster than water.

As a side note don't scuff/sand without removing blush, it just spreads it around and pushes it into the score marks from the sanding. Once it's in the sanding marks I expect it would be about impossible to get out without major grinding. Wipe before you sand.

Swamp

 

shows what i know about varnish...i would've put a good 2 part primer over the west,and sprayed it in awlgrip...

don't do varnish - isn't that for coffee tables and other furniture ? composites and varnish don't go together well...

 

My experience is with West System and MarinEpoxy. The West System blushed terribly despite using slow hardener. The MarinEpoxy from Boat Builder Central has not blushed yet using slow, medium or fast hardener.

From what I understand any epoxy can blush under the right conditions. High humidity, fast hardeners and fumes from kerosene or propane heaters are supposed to be the most common suspects for inducing blush according to what I've heard. I take no chances and wipe everything down with acetone before I lay epoxy. With the West System I had to wash it down with soap and water. The blush was too thick for a simple epoxy wipe-down. Based on that experience, I won't use it ever again if I can avoid it.

I've never used Raka epoxy, but a lot of guys here have and will respond eventually. I've never known anyone here to use Silvertip. It is supposed to be excellent, but it is outside my budget.

Nate

 

I have used Raka for years. I have built both boats and airplanes with it. The 350 hardener is called a non-blushing hardener when used with 900 or 127 resin (at least as I remember it). My shop is heated and AC ed as well. I never tried it exposed to weather, but will say it seemed a great combination when used inside.

Frank_S