Vaccuum pump care etc

Nick M Singer · Post by **Nick M Singer** » Wed, May 10 2006, 9:41AM

I posted in another thread: \"Whilst we are on the subject of fly-cutting waste boards I have always been concerned about this process because of excessive air flow through the vacuum pump. It is a long process (especially on my 7 x 10 table) and I wondered what the rest of you feel about this because of possible damage to the pump?\" I got no feed back on this topic and wondered if anyone had any ideas on this or any other tips on general pump care?

Dave Burtchell · Post by **Dave Burtchell** » Wed, May 10 2006, 4:55PM

Nick,

What kind of pump do you have?

Dave

Michael Kowalczyk · Post by **Michael Kowalczyk** » Wed, May 10 2006, 8:51PM

I use 2 different pumps. a 5hp Bush for my dedicated spoil boards and a 20 hp Travaini for Ecab, prototypes and short runs on my universal LDF. I still have and continue to use the original one that came with the C40 in 2002. I have only had to fly cut it 2-3 times so far. I built a room around the CNC and have a Dedicated 1 1/2 ton AC just for that room. So I keep the environment somewhat under control during the sultry hot and humid summers ( 100 degrees (but feels like 115) and 98% humidity) here in beautiful Houston, Texas.
We run the 5hp daily for 7-8 hours a day non stop almost and it runs great. just change the oil and filter and keep it clean from sawdust. About once a month I have one of the guys wipe them down completely just like you would if you were going to sell it. They are suppose to check the filter weekly or if there is a loss of vacuum and there could have been dust sucked up by the vacuum.

The Travaini maintains about 20-22 inches while cutting wood and has about 360 CFM.The Bush holds a solid 25+ when it is running and we are cutting Melamine and I think it is about 60-70 CFM. Boy is it quiet. I have had the operator leave and forget it was running a few times. Just glad that I found it quickly and he hasn't fogetten it since.

Let me kow if you have any specific questions.

Brian Shannon · Post by **Brian Shannon** » Wed, May 10 2006, 9:12PM

Nick,

Great topic. I would like to see lots of feedback on this topic. I have a 15 HP Busch. The rebuild kit(filters and seals) is $750.00!!!!!!!!!! What do I REALLY need to do to maintain it?.

Michael,

Do you have a 5 HP or 15 HP Busch pump?

Bill Rutherford · Post by **Bill Rutherford** » Thu, May 11 2006, 5:32AM

Brian,
We are also running a 15HP Busch pump. We change oil and filter every three months. Busch has told me it is not necessary to change the oil filter every time we do an oil change but the filter holds quite a bit of oil. We do the intake and exhaust filters once a year. You are correct the kit is pricey but then again, so is a new pump! The only thing I could not get a solid answer on is the grease fittings on the Toshiba motot, from what I found out they need to be greased once every three years or so, even then they need to be purged as they are greased.

Hope this helps

Nick M Singer · Post by **Nick M Singer** » Thu, May 11 2006, 10:27AM

I have a 7.5Kw PVR unit does about 400 cubic litres. Not quite enough for the size of my table but will be buying another to run in tandem. I have heard that it is not a good idea to run these things under atmosphere for any length of time because it clogs the filters with oil and can burn out the motor, oops!!

Michael Kowalczyk · Post by **Michael Kowalczyk** » Thu, May 11 2006, 2:58PM

Hey Brian,

It's a 5HP.

David Hall · Post by **David Hall** » Tue, Jun 13 2006, 6:52PM

I've got a 5 x 10 table with the 18hp Becker vacuum pump. I just replaced the spoilboard for the first time (machined both sides) and it's pulling about 18\" with nothing on the table. This seems high compared to the board that was on the machine previously. Getting a solid 23\" with most of the table covered with a sheet.

What kind of vacuum numbers are you seeing with nothing on the table?
What do you get with most of the table covered?

Thanks
Dave

Nick M Singer · Post by **Nick M Singer** » Wed, Jun 14 2006, 12:32AM

Hi Dave

I have not got a vacuum meter so I will get one soon and test the pump. All I know is that of late my parts are not holding as well even though my filters are very clean. I am thinking of running 2 x 7.5KW units in tandem which should suck the operator to the table if he is not careful, Any one had experience with putting a reservoir tank into the system?

David Hall · Post by **David Hall** » Wed, Jun 14 2006, 7:52AM

Hi Nick,
Two pumps running at the same time may not have the dramatic effect you hope for. The pump(s) have a maximum vacuum they can achieve. It doesn't matter if you have one pump or 10 you will still only achieve the maximum vacuum of the best one pump.

Additional pumps will increase the volume of air being pulled through the table. If your vacuum pressure is dropping as the parts are cut (and areas of the table are exposed) the additional CFM may allow the multiple pump set-up to maintain a higher vacuum.

Regards,
Dave

Brian Shannon · Post by **Brian Shannon** » Wed, Jun 14 2006, 12:03PM

I'll check my vacuum #'s when I get to the shop. I have a 5 x 8 with a 15 HP Busch pump. I did see improvement after I seeled the edges of the spoilboard with some watered down glue. I also seeled 6\" on each side of the top because only use 4 x 8 sheets. I also use a 1/4 x 4 x 8 wasteboard which also improved holding. Once I had to machine some 1\" MDF. Just for fun, I placed a 2' x 2' pc. of Melamine on top. It seemed to hold even better through the 3/4 and 1/4 and 1\".

Brian Shannon · Post by **Brian Shannon** » Thu, Jun 15 2006, 1:39PM

22\" with 1/4\" mdf wasteboard on

24\" with 3/4\" Melamine on that

30\" with gate closed.

David Hall · Post by **David Hall** » Thu, Jun 15 2006, 2:13PM

Thanks Brian.

Regards,
Dave

Michael Kowalczyk · Post by **Michael Kowalczyk** » Thu, Jun 15 2006, 7:51PM

Hey Nick,

make sure you get a check valve on your pumps. I talked to Bush, no not the President, Pumps and they have a system that uses a check valve.

The res. tank really only helps on the initial suck down (for lack of a better term) otherwise my understanding is it does nothing else.

Cheers,

Thermwood / eCabinet Systems

Vaccuum pump care etc

Vaccuum pump care etc

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