Pressure or Vacuum

[clogs]

I half asked before about using a pressure pot or a vac chamber.......
seem to remember that most use pressure to eliminate air bubbles from resin.....
Is this because of cost as most have a compressor.....?

I always thought that using vacuum would be best.....seems more natural me but what do I know.....lol......

Take a look at this chap.....about a 1/3'rd of the way thru....
really good results with vacuum.....



just interested......
have a good weekend.......

 

[MF1000]

Pressure would just make the bubbles smaller, vacuum expands them and they fuse to the surface to dissipate. Using resin on a river table or similar you use a heat gun to locally raise the temp of resin with a bubble in it so it expands and bursts on the surface.

 

[sawtooth-9]

Vac chamber would be much better.
For smaller items, you could try connecting the compressor inlet to the vac chamber. If you have an air inlet valve between the vac chamber and compressor inlet, you can still provide some air to feed the compressor and regulate the dregree of vacuum you create.
Just an idea.

 

[SimonStevensCanes]

I believe those that stabilise wood use both. Vacuum to get all the air out, then pressure to force all the resin in.

 

[Sachakins]

If its wood stabilisation, then vacuum chamber with cactus juice, then bake the wood off in foil in an oven.
If it's for resin infill, ie a holey blank for turning, then a pressure pot is best.
The thicker resin doesn't do well under vacuum, it sets more rapidly and can trap air in it.
Some actually gas off the thicker resin in a vacuum first to minimise bubbles from mixing, but only for a minute or two, then pour onto blank or into a mould and bang into a pressure pot.

It really does depend on what you are trying to achieve.