Need Help!- Vacuum Pump Pressure

[mbessant]

We have a Thermwood C67 with a 10 x 10 table and a Busch R5 0400 Vacuum Pump.

We are trying to set up a spoilboard on 1 half of the table using a universal vacuum.

With a 3/4" MDF what pressure should we be looking at?

What pressure can the pump deal with, at the moment at -20"Hg it pumps oil and smoke out the exhaust?

Thanks for your help

Martyn

[One of Many]

The pump should reach 29" as long as there are no leaks in the system. When using a spoil board, cover all unused areas with 3-5mil plastic sheet taped down at the edges and the sides of the spoil board tape sealed around the periphery

The Exhaust Filter may not be seated. sealed, cracked or clogged.
If there is an oil return valve, it may be stuck open or the return line clogged.

Poor vacuum build can also be related to dirty oil or worn internals if no external leaks can be found.

It sounds like some good TLC maintenance would help. Do not use a detergent oils in these pumps. Bosch R530 is standard oil and R570-590 is for high ambient temp environments.

DC

[mbessant]

Thanks for the info.

I have got someone coming in today to have a look at the filters.


I will be using all the spoilboard, I have sealed the edges with epoxy resin.

Do you know what pressure the pump can go to before it gets overworked?


Martyn

[Geof]

Originally Posted by mbessant ...What pressure can the pump deal with, at the moment at -20"Hg it pumps oil and smoke out the exhaust?....

Originally Posted by mbessant ...Do you know what pressure the pump can go to before it gets overworked?.....

As One of Many says your pump should be able to pull a vacuum of about 29 inches.

If it is only getting to 20 and is blowing smoke you probably have a leak in the system.

You have to remember that a vacuum pump is the opposite of a compressor; as a vacuum pump pulls a better vacuum on a well sealed system it actually does less work.

The problem is that when you are using an MDF spoil board you have a leaky system; sealing the edges is a good idea, and masking any area on the spoil board not covered by the workpiece.

You want to have the pump pulling the best vacuum possible, in other words the minimum amount of leakage possible, because then the pump is actually doing less work.