I am an old git trying to waterproof a new model boat using EL2 Epoxy Laminating Resin.  The planks are Mahogany and I have stained it with Ronseal mahogany dye, then grain filled it with grain filler.  I have carried out a test using spare wood and the resin looks good when applied but forms streaks and separates after a few minutes.  I have also tried it after applying 25g Woven Glass Ultra Light Plain Weave, this gives it an orange peal effect.  What am I doing wrong.  Help please
Roy. 

Sounds like the surface needs a key with sandpaper and a clean as something on the wood surface is causing the resin to be repelled and separating out as you describe.   Certainly like that you are unlikely to get a good bond.


Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

+x

 

Warren (Staff) - 11/15/2018 5:28:17 PM

Sounds like the surface needs a key with sandpaper and a clean as something on the wood surface is causing the resin to be repelled and separating out as you describe.   Certainly like that you are unlikely to get a good bond.

Thanks for the prompt reply.  I will key the surface, clean it and give it a go.
Regards Roy.

Hi Warren.
I have keyed the surface with 400 grit [as I don't want marks to be witnessed through the finish], and cleaned the surface with acetone.  Samples show the same effect [even without dye].  Is the epoxy [ Lot number 123247] and Hardener [Lot 126221] in shelf life?  I purchased these items on 07/09/18.

Both the hardener and resin are well in date so I doubt that is an issue.

What sort of temperature are you working at?

Is there any moisture in the wood?

Have you got any photo's? I would expect pretty much any epoxy to stick to a well keyed wooden surface without too many issues.

What has it been treated with in the past:?  with woods porous nature stuff can get very deep in the wood  and may still cause issues later on even with surface sanding.


Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

+x

 

Warren (Staff) - 11/21/2018 5:11:53 PM

Both the hardener and resin are well in date so I doubt that is an issue.

What sort of temperature are you working at?

Is there any moisture in the wood?

Have you got any photo's? I would expect pretty much any epoxy to stick to a well keyed wooden surface without too many issues.

What has it been treated with in the past:?  with woods porous nature stuff can get very deep in the wood  and may still cause issues later on even with surface sanding.

1. The temperature varies but recently it has been between 14C and 18C.
2. The wood is dry.
3. Photo's attached [I don't think that they are much help though].  Photo's show after keying and cleaning.
4. The wood used is cut and finished from unused wood, although as I mentioned before, on the boat it has been stained and grain filled].
5. Am I expecting too much.
If I cannot improve the finish, would it be worth me coating the wood with a standard wood varnish and then epoxying and glass matting over the top

.

The temperature is quite low at the bottom end of your scale which is not ideal.  From the picture it almost looks like you need to brush on in thinner layers and build up a thickness that way.

All a wood varnish would do is to seal the surface -  you could brush a very thin layer of resin over the wood surface to seal it as well.


Warren Penalver
Easy Composites / Carbon Mods - Technical Support Assistant

+x

 

Warren (Staff) - 11/22/2018 10:11:11 AM

The temperature is quite low at the bottom end of your scale which is not ideal.  From the picture it almost looks like you need to brush on in thinner layers and build up a thickness that way.

All a wood varnish would do is to seal the surface -  you could brush a very thin layer of resin over the wood surface to seal it as well.

I will try to elevate the temperature. 
The photo's show the thinnest layer I can apply with a brush.  Should I apply the first coat with a lint free cloth, or can I thin the epoxy, with acetone.
Once again, thanks for your advice.