epoxy glue advice

[doyenofcastle]

Hi ,

I am planning to do some stock from mahogany and teak lamination using epoxy 2 part ,I have done before few stock and didn't read in deep a bout epoxy glue ,some stock glued morning and some afternoon ,I was reading best results can be got if u prevent bubbles from forming ,so u need to glue at afternoon so the curing will be done when temperature decreased to night ,but if apply in morning the temp will be increased and bubble can form ,I tried to followed but I don't have enough time during the day except early morning so is the there any serious issue if u glued and temperature increase but u keep your stock in shadow (temp this days is range 30-25 C )

 

[mariusshobo]

I do not think that the reaction between the resin and the hardener will create bubbles; this are created when stirring the mixture in the jar. I was curios and look at the leftover cured mixture from the jar after curing and there were no bubbles.
But if you paint the stock with epoxy, then you sealed the wood and expanding air (expanding due to increasing temperature) trapped into the wood can create bubbles.
But there should be no bubbles problem in laminating the stock.

 

[Marco van Wyk]

Hi there…Foxfish gave me an idée to warm up the wood and epoxy containers before mixing.
That will get rid off most the air when the epoxy starts heating in the curing process.
Never had a problem epoxy blanks together, thou when sealing with epoxy, lots of bubbles comes out.
I will warm both up a bit with a heat gun or hairdryer.
Mahogany is much more porous than teak, when I sealed the inside of my air pockets,
the epoxy came right thru to the outside of the wood at a few spots.

 

[Guffer]

If there is air in your resin when it has set then something has gone wrong in the prep, most likely over vigorous stiring as mentioned above. You can get slower hardeners which might be better suited to a warmer environment. You gave us the temperature but didn't say if it is humid also? If it is then you may get amine blush on the cured epoxy which can be washed off with warm water and a brillo pad. From memory I think there is an issue with teak the natural oil in the wood, you may have to strip the oil off the surface first using acetone before applying epoxy.

Good luck! Be sure to show us the results!

 

[SilentStoning]

It is my understanding that acetone should not be used. Especially prior to laminating. A gun company actually had issues with delamination due to use of acetone. Before I apply epoxy I wipe down my wood with a dry rag (one that will not leave little pieces behind) then take the air compressor to it to blow everything off. Never had a problem with that method.

 

[foxfish]

I think doyonofcastel (do you have an easier name?) lives in a hot and sticky country?
Epoxy is useable up to around 44c but it will start smoking if it is kept at that temp for more than a few minuets.
So if you can store the wood at the lowest temp possible and then heat the surface to 40 - 42c but keep the epoxy mix at ambient temp then you will have the best chance of deep penertratsion into the surface.
However epoxy is not the easiest product to work with and I often stuggle with it during warm summers (25c).
Use slow hardner,work in the coolest location, keep the mix at room temp but get the wood surface slightly warmer (hair dryer) but probily the most important is avoiding high humidity.
Thinning epoxy with acetone will weaken the joint but can still be appropriate when deep waterproofing is more important than joint strength,
I find that when the air temperature is around 15-20c I get the best results from epoxy, I usually warm the mix to around 20c and the wood surface to around 30c but work in a cool shady location if possible.
Adding colour pigments can also effect the performance and adding powders can increase the performance ... Lot to learn about using epoxy, easy to make mistakes too!