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Hi there.
I dont supose anyone might know how to stop a mass of air bubbles coming from end grain timber while casting timber & epoxy resin. After the pour it apears to be clear but when i come back to it when its cured there has been an explosion of tiny air bubbles on the end grain. Im guessing some form of treatment before i pour the resin?
Any help or advice would be great!!
Thanks
Shane.
What resin are you using? If Polyester or Polyurethane Resins then if the wood is not completely dry, I mean 0% MC not just OMC, they will react with resin creating bubbles.
You can use pressure casting but it would be better using an Epoxy casting resin as it is more tolerant of moisture.
Yep, I have had this trouble before. I do not use a vacuum process. So if you are, then disregard any further.
I make sure to seal the end grain with a shellac or WOP. Then pour in the resin. I let it settle and 'blow out" any bubbles with a fine stream of air. I use an old ball inflating nozzle. The type you use with a bicycle pump. I cut the end of the nozzle off and attached a flexible clear plastic hose to it. Then I go around the edges of the end grain and gently blow down into the resin to lift out the bubbles.
I doubt that any of this would work in a pressure pot or vacuum system though.
Lyle.
Spray deodrant on them as they form, I know this works with epoxy resin. I haven't used any other resins to try it on them.
pressure pot or portagas the top also helps remove some air bubble but lots i be looking at how you are mixing, pouring fast or moisture
keep on plugging away
It could possibly be that the heat from the chemical reaction of the resin is causing outgassing of the timber.
Unless your using a pressure cooker try keep the ratio of resin down and the ratio of wood up. The less resin bulk the better results I get.
It's a simple fix. Coat the end grain with a thin layer of resin first. Let it cure and this will seal the pores of the timber which is the cause of the air bubbles. When cured do the rest of your resin pour.
Well I just created a thread for this too, this has been helpful :D