Epoxy bubbles.
- Thread starter sean69
- Start date
I have tried that - I find it really cuts down the working time.
I tried that as well - I have about a 75 minute working time with the 2 part G2 system.
Thing is I usually mix it with microfibres or silica so it gets pretty thick (think about as thick as Acraglas) , bubbles won't just float out.
I've even tried a vacuum chamber..
As I said the bubbles are usually introduce in the mixing... try this ... bend a small loop in the end of a straight piece of welding rod about 6 inches long. Chuck this in your drill press. Insert your cup of epoxy over this stirring stick and turn on your drill press. move the cup around allowing it to be mixed... don't remove the cup while the press is spinning. it takes quite awhile but fewer bubbles should be introduced. The only good thing about bubbles are they are a cosmetic flaw, they don't really affect the accuracy. You can kind of probe the epoxy when it is in the stock like they do when pouring cement in a column.
https://en.wikipedia.org/wiki/Bain-marie
With most epoxies, warming the mix slightly lowers the viscosity and enables the bubbles to rise to the surface, and it usually helps with curing too.
With most epoxies, warming the mix slightly lowers the viscosity and enables the bubbles to rise to the surface, and it usually helps with curing too.
when I build fishing rods I use a small flame to release bubbles that come from the epoxy displacing the air as it soaks into the rod wrappings.
I use a vac chamber after mixing and then light flame heat to release any bubbles.
I can't see how a person could use this method for releasing bubbles from bedding epoxy though...… I would try guntech's solution. Mixing in that fashion would also break up the bubbles and give a smoother mix.
I use a vac chamber after mixing and then light flame heat to release any bubbles.
I can't see how a person could use this method for releasing bubbles from bedding epoxy though...… I would try guntech's solution. Mixing in that fashion would also break up the bubbles and give a smoother mix.
If it’s 24 hour epoxy , it best to put it in a vacuum chamber for a bit (30 minutes) should do , and then use. If your worried about getting bubbles , after you pour. Use a Palm sander, with no sanding paper on it , maybe put some soft clothes on the bottom and hold against your rifle stock your bedding, this will help the bubble raise to the top and out....pour slow...don’t stir, or use a stick to scoop it out....a pop stick to help push it a little,....will help with most ,if not all of your bubbles problem.
Cheers
Brian
Cheers
Brian
Heat gun or hair dryer will work and also tapping with a mallet.
My experience has been with:
1) Making linear motor coils from scratch with a ceramic epoxy (tapping rubber mallet method on mold)
and
2) heat gun on resin/woven carbon fiber using the heat gun.
My experience has been with:
1) Making linear motor coils from scratch with a ceramic epoxy (tapping rubber mallet method on mold)
and
2) heat gun on resin/woven carbon fiber using the heat gun.
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worth a try! - as cosmetic as they are, they do look like hell.
I have a Swedish M96 here that had been tricked out for competition around 1950 heavy barrel, elm stock - the action bedding doesn't have even as much as a pin hole in it ... wondering how they managed that. Interesting, yet again, the compound is generally too thick for something like that to work..
I actually just bought a palette knife the other day (yesterday??) & am going to see if mixing it on a surface stone will help...
Mom has something called a 'pug mill' for mixing clay - it somehow magically works all the air out as it extrudes the clay... WAY too large for something like this, but I wonder if there is a physical principle at work there that can be applied here?
I just let my mixed, slow cure epoxy rest for about 10 min and then heat it up gently with a hair dryer to get rid of the air introduced during mixing. If you want to elliminate imperfections in the bedding surface, just apply the bedding compound to the stock and also to the action. I use good quality masking tape to reduce the epoxy spillage when it all "squeezes out". The finished surface is ussualy near perfect.
I deal with epoxies quite bit at work. Our experience is that humidity is the #1 cause of bubbles in the epoxy/urethane. So much so, that 1 of our bays is in complete isolation and we control humidity via air driers and A/C.
Not sure if the same thing is at work here, but just stating my experience. (bubbles in our system, causes an immediate shut down @ approx $10K an hour loss until the problem is fixed.)
Not sure if the same thing is at work here, but just stating my experience. (bubbles in our system, causes an immediate shut down @ approx $10K an hour loss until the problem is fixed.)
- Location
- West Quebec
That's what I thought and do as well
I used to build fishing rods and once took a tour of the St Croix rod factory in Wisconsin. They told me and I have seen it elsewhere since that it is not the heat but the carbon dioxide from the flame that releases the air bubbles. At the factory, once the rod was mounted in the turning apparatus and the epoxy applied they simply passed the flame from a Bic lighter for 2 or 3 seconds under each wrap to release the bubbles and make the epoxy clear as water. It helps to not stir the mix too vigorously also.
I can do it with my propane torch or the gas stove in the kitchen and don't need to hold the epoxy close enough or long enough to warm it up.....just expose it to the Carbon Dioxide created by the combustion.
I can do it with my propane torch or the gas stove in the kitchen and don't need to hold the epoxy close enough or long enough to warm it up.....just expose it to the Carbon Dioxide created by the combustion.
Medical and dental epoxies come with dual chamber syringes and mixing nozzles like these: https://www.amazon.ca/Simpson-Strong-EMN221-RP10-Mixing-Nozzle/dp/B0055PMTP4 This allows for thorough mixing without introducing air.
