Ney Q50 Pressing furnace

[adamb4321]

Anybody got a Ney Q50 pressing furnace. I've got one that I dug out of storage and fired up at the weekend but I cant remember what vacuum level (mm) that it's supposed to achieve.

 

[ps2thtec]

On the older Ney model I had the preset vac value was 101% for pressing. That's what was required for pressing.

 

[adamb4321]

Yes, I've got it set at 101% vac (makes the pump run continuously rather than cutting off and holding the vac) I'm more interested in the actual vacuum level achieved. I'm getting about 644mm on mine and wasn't sure if this was right or a bit low.

 

[ps2thtec]

Might be low,...after this thread a couple months ago I set my oven at 740. The pump has to strong enough to pull that. Other variables to consider also. The oven I repaired was not my old ney.
http://dentallabnetwork.com/forums/threads/vacuum-levels-as-it-relates-to-porcelain.19102/

 

[ps2thtec]

Might be low,...after this thread a couple months ago I set my oven at 740. The pump has to strong enough to pull that. Other variables to consider also. The oven I repaired was not my old ney.
http://dentallabnetwork.com/forums/threads/vacuum-levels-as-it-relates-to-porcelain.19102/

 

[adamb4321]

I tried a different pump that pulls 750mm on a different furnace, it got the Ney to 20mm higher than the original pump so the pump probably needs a service. I also pressed a test ring with some veneers on it, that pressed perfectly using the old pump.