My question is after vacuuming all the air bubbles out instead of using a soak process would it benefit the penetration of the stablizing resin to put it a pressure pot under 50 psi? If so how long would you leave it under pressure? Thank you
Shane, it's entirely possible to stabilize wood without either vacuum or pressure, all either does is accelerate the saturation process; vacuum by removing the air from the piece, allowing the resin to soak in quicker; pressure by forcing the resin into any voids in the structure of the wood, pushing the air out.
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Would it benefit penetration of the stablizing resin to put it in a pressure pot under 50 psi?"
- Yes... it will force the resin into the wood faster than simple soaking.
- Yes... it will penetrate deeper, in a shorter amount of time.
- NO... you cannot force more resin into the piece than it is capable of holding. See above two lines.
The structure of the wood only has so much capacity to hold resin, you can't put any more in there once you reach the point of saturation. (
For the professors in the crowd - According to the laws of physics... Yes, the saturation point does increase slightly under pressure, but unless your oven is under pressure, what little extra you manage to force in there is going to seep out after you remove it from pressure to cook it.)
Bottom line is, all you're doing is reducing the amount of time you need to soak after vacuum. That's your only benefit.
So I have 2 blocks in the vacuum pot right now. The were under vacuum for 23 hours, then the vacuum was released and will soak for 24 hours. Then planing on running a 50 pound pressure cycle. How long under 50 pounds of pressure would you think?
Depends totally upon size and density of the blocks. If they're pen blanks 24 hours should be more than adequate. If they're call blanks, it's very possible that's adequate. Depends totally upon how thoroughly the resin penetrated under vacuum and soak.
Personally, I ran it both ways - vacuum, soak, and pressure cycle. And vacuum, pressure cycle, and soak.
I really haven't seen a lot of benefit in it either way, other than the potential to reduce soak time. My blanks didn't appear any different, didn't feel any heavier, although I didn't weigh any of them to determine if there was any minute difference. I did see more resin cook out of my blanks when running pressure last however.
Most of the time I throw stuff in the vacuum pot and let it soak up to a week, (
unless I'm first round trying to dye it). Typically, I'll leave it sit in my vacuum pot, and I may pull vacuum on it 5 - 6 times while it soaks. Have left it under vacuum up to a week, and vacuumed, bled vacuum off, and pulled it down again repeatedly. I seldom see a blank float when I'm done. If it's dense enough to sink to begin with, it probably isn't going to take much resin no matter what you do to it.
Thanks for the response guys. I will be putting the first batch in the pressure tank tomorrow to start my research.
Again, how long you leave it Shane is dependent upon size of the blanks, and how dense they are. Somewhere in the 24 - 48 hour range should be more than adequate.