I have a problem I hope someone can assist me with. I have been casting pen blanks with slow cure Alumilite and wood stabilized with Cactus juice. The Alumilite becomes foamy where the plastic meets the stabilized wood. Anyone know why and how to prevent this? I vacuum processed the alumilite and also heated the alumilite to assist in moisture removal. This doesn't appear to be the problem. The Alumilite is perfectly clear and hard in areas not immediately in contact with the wood. Thanks,
Post by carol - Alumilite Corp on Mar 23, 2018 14:44:32 GMT -5
It is coming in contact with moisture somewhere. You stated where it hit the wood, those spots are foaming. If it were the resin it would be foaming throughout the piece Penman. A simple way to test that is to blend an ounce of A and an ounce of B let it cure in a cup, see if you get any foaming Penman.
I've had the same issue. I purchased the resin from amazon ($40) back in September, but just opened it up and tried it yesterday. The "Part B" was very thick and difficult to dispense. The mix began to foam after about a couple hours. It was very slow to set up, well over an hour. I now have to scrape the porous foamy material out if the piece I was going to work on.
Is this material very sensitive to cold temperatures? I have other dirt-cheap casting resin that has lasted for years with no issue at high temp and humidity, sub freezing temperatures, etc.
Cold does have a bit of effect on it, usually slows the cure but foaming is normally a moisture problem. If one part is too thick and hard to pour you can carefully "warm" it to thin it out. Put very warm (don't use very hot or you might melt the bottle) water in a bowl and put the tightly capped bottle in it - making sure to keep the bottle upright. It shouldn't take long to warm the side up, I've done it in just a couple minutes myself.
You also might have an "old" batch and/or one that has be subjected to extreme highs or lows during storage. Sometimes an old batch will last just fine in storage as long as the temperature is fairly stable but being exposed to too much up and down temperatures will cause problems. Warming the mold and/or warming the unmixed resin will help. Also sometimes raising the surrounding environment temperature helps - I'll raise the temperature in the area I'm working in sometimes if I see foaming on a casting after I toss the bad casting and start another one.
I am having the same foaming problem with worthless wood that was stabilized with Cactus Juice. Since Cactus Juice does not completely fill the cavities of the porous wood, I am thinking the foaming might be from air trying to escape the wood as the Alumilite is working its way inside the wood. I used a pressure pot at 60 psi and still had this problem.
If the wood is still retaining moisture it will have an effect on the Alumilite. I'm not exactly sure what effect Cactus juice would have on the Alumilite as its stabilizing the wood, but is it (Cactus juice) sealing it like a wood deck finish......Thompson's Waterseal , or any other exterior waterproofing sealer....my line of thinking is instead of sealing the wood to prevent water from getting in, sealing the wood to prevent whatever moister is inside , from seeping out.