Thread: Vacuum&pressure pot experiments

I m not really in the know on this subject but would like to try some things with some bone that I purchased. I bought it to carve, but it has been bleached and whatever process they used to bleach the bone left it very dry and brittle. It is not nice to work with at all. I soaked a couple of pieces in some light mineral oil and on the surface they are much nicer they need better penetration. I don't want to sink a ton into the project, and I have a vacuum pump. As long as I am not dealing with any glass part it should be simple enough to rig up an airtight container to do my trials in. So here is my silly question, is there anyone with experience following this or perhaps B52 may have had some early experiments along these lines that I could gleam a little info from.

I used a glass cookie jar for my vac chamber as seen in the first page Shaun but a steel ice bucket would work as well for the chamber. Or even a big mason or pickle jar.
I put that tusk in mineral oil in the vac chamber to pull the oil in without ill effect.
Might help save that brittle bone if you can get some oil in there for sure.

Originally Posted by MikeB52

I used a glass cookie jar for my vac chamber as seen in the first page Shaun but a steel ice bucket would work as well for the chamber. Or even a big mason or pickle jar.
I put that tusk in mineral oil in the vac chamber to pull the oil in without ill effect.
Might help save that brittle bone if you can get some oil in there for sure.

I've played with some bone in my vacuum chamber and I was amazed at how much stabilzer solution was pulled in.

Just a thought.

Pretty damn cold outside this weekend so in the shop messin around with these scale blanks some more.
Didn't like how easily the first one snapped so thought I should run some destructive tests before investing in a razor.
I pulled out my digital scale and sacrificed the thinnest set to some force testing. Basically I placed the end on the scale and flexed down, against the weighing surface until the scales snapped and recorded the gram force required.
Didn't have the phone handy for pictures but they broke at around 85 grams force. Or about 3/4 of an ounce pressure. Not enough as far as I'm concerned. Sure they might get stronger after final finish and sealing but I decided maybe another go throug the stabilizer and vac pot might help, or might not hurt anyway. Plus I was curious.
So I used a sandwich baggy as my solution tank and put a pair back in the pot and pulled 28" of vacuum on them again.
Much to my surprise a boat load of air started coming out of the wooden parts of the blanks once again despite already been stabilized as a solid block of wood before casting.

This looked promising so I proceeded to leave them in there till no air was being drawn out, then I shut down the vacuum and slowly balanced the pressure, but left the blanks in the bag submerged for an hr before moving them to the oven @200f. Turned them every ten minutes for 40 minutes and let them cool.

Did the same process to all five remaining sets and they seem much more 'stable', Unlike me, hehe. Harder, stiffer and the wood just looks more 'filled'.
But are they any stronger?


Actually snapped at around 530 grams force then spiked as I took the pic.
So I think the double soak in stabilizer helped.
And I also am trying that stacked on brass idea with the set I already started as they are to far along to rebake.

Cheers gents.

They are beautiful Mike.

85 grams is 3 ounces. ¼pound!
~Richard

Thanks gents, Richard, quit showing off your rain man math skills, hehe.
And thanks, you are right of course. Did it in my head, first mistake right there.
So my post treatment force is now 18.5 oz, or just over a lb force to snap. Better, but still delicate. Enough to proceed though.

It makes perfect sense in my mind that your penetration would only be in the first little bit of the wood and the vacuum would pull a lot more air once the pieces were cut. I am also wondering how you prepared your pieces of wood for the process to start with. Looking at your first broken piece it looks like it broke at a bark edge and better prep on your pieces might be another piece of the puzzle. Perhaps a good wire brushing with a dremel may help, and being more selective to the orientation of your pieces. I think the end results are beautiful and amazing. I am trying to think through the last 1 or 2% of the puzzle to perfection. The pieces on the brass look like they are going to be dazzling too. As always your project have my attention.

Good eye shaun, am thinking the same regarding wire wheel bark and crud removal. I did leave the first burls dirty, wrongly thinking it'd all look cool sealed in au' natural like.
Learning from these mistakes, that's the fun part of these experiments, hence the thread name..
Every success built on a pile of failures..

True. We often learn the most from what is in the rubbish bin!