On 11/24/2016 7:22 PM, notbob wrote:
> On 2016-11-24, graham > wrote:
>
>> spectacular colour or figure. On the lathe, this tears badly so
>> impregnating with epoxy would stabilise it.
>
> I see now. Makes sense that pen/knife makers would jump on this
> technique. Did you note the vac chamber links? I don't have a wood
> lathe, but I do have a vacuum pump.
>
> nb
>
I have an old vacuum pump and it uses thick-walled rubber tubing as a
connector.
I was intrigued to see the type of resin they were using. My intention
is to use a thin epoxy with a 2 hour setting period. The reason for
using a canner is that I want to use it for large bowls in Box Elder
burl which often has punky areas and tears out easily, even with very
sharp tools. I hope to rough turn the outside and then liberally coat
with epoxy, vacuum treat, then finish turn. Similarly, after getting
close to the finish profile on the inside, do the same. Note that I
wouldn't need penetration of more than ~10mm.
Obviously, I'll be experimenting a lot. But first I need to find a large
canner.
In oil exploration, consultants impregnate rock samples with blue epoxy
in a vacuum oven. Then they examine thin sections under the microscope
and can easily estimate the porosity of the rock by estimating the area
of blue amongst the mineral grains.

On 2016-11-25, graham > wrote:

> wouldn't need penetration of more than ~10mm.
> Obviously, I'll be experimenting a lot. But first I need to find a large
> canner.

Living in CO, I know vacuum systems are used fer cannabis extraction.
You might try looking on ebay for "cannabis extraction" vessels. I
seem to recall seeing one person creating dedicated vacuum vessels
outta pressure cooker pots fer jes such a purpose.

nb