gast vacuum pump?

[whalems]

I am thinking of going to vacuum this year and wonder if this pump would work? How many taps is it good for? Any suggestions/comments welcome. Thanks, Mike

http://www.ebay.com/itm/Gast-Vacuum-Pumps-/270612539967?pt=BI_Pumps&hash=item3f01c3aa3f

[Teuchtar]

Doesn't look big enough for your operation. You need to think of 6 cfm at 20"HG for your 600 taps. Probably 1-1/2 HP of vacuum pumping.

[jfroe939]

I'm not a vacuum guru, but I'll try answering this... A couple things to note with gasts... The one on Ebay, Model # 0211-P78A-G8CX
The "P" in the model name indicates it's for pressure. You'll want to find one that has a "V" in the name, which indicates it's for vacuum.
If you check this link ...
http://www.gastmfg.com/rotaryvane.html
... find the "cfm" column and go down until you start hitting higher numbers. I hear you want 1 cfm per 100 trees minimum. Take the 1550 models for example, if one were to choose the 550-V138K-G34AX model, we see the V is in there for vacuum and then when we look at the line chart that shows the 1440 rpm line where it hits the vacuum level. Even though at zero impedance or restriction to airflow the pump is possible of hitting 11.0~ cfm, after vacuum has built up to say 20 Hg, because airflow is impeded, true cfm is somewhere around 2. That's sounds worrisome, but if you have a pretty airtight tubing setup you'd be okay probably close to max (1000 trees?) But as soon as a squirrel chews through a line you'll see vac drop - which is true of all vacs. The only difference being that "milking-machine" style vacs can recuperate or even hold high vac potentially if one end of your tubing has a small hole, whereas with smaller vacuum with lower cfm's can't deal with holes very well. Maintain a tight system and you can get by without a bigger vac. So "potentially", you could run 500 trees on 2 cfm with no leaks. It's fair to assume that a normal system of hundreds of trees will have just a smidge of leaks around fittings if they didn't fit just right, as is human, and that higher cfm vacs can overcome the offsetting results of these small leaks. It kinda comes down to challenging fate versus feeling confident and safe. But make no mistake, small gast vacuums work like a charm if you have time to watch over your fittings and you feel like you did a good job putting lines together.

[whalems]

Thanks for the input. I will keep looking.

[500592]

The gast 1550 at 20 inches are 5 cfm and are good for 500 taps

[brookledge]

If you are interested I just posted a Gast 3040V115A for sale It is rated for 31CFM at 20"
Keith

[vtwoody]

Will this work? I'm still trying to get a clear picture on what all the specs mean (and which are relevant to our intended use)....?



http://www.ebay.com/itm/GAST-3-5-cfm-22-25-Hg-Vacuum-Veneer-Pond-Aerate-Compressor-Airbrush-/280757227468?pt=BI_Air_Compressors&hash=item415e6f4fcc

[Greenwich Maple Man]

So would these pumps work as well as a Surge on five hundred taps!!!! Anybodys thoughts??????

[metalhead62]

hey green im not a vac expert but i dont think either of them will run 500 taps now that 3040 that brookledge has is more than big enough i dont know anything about him or them but the specs r good

[maple maniac65]

They will not run 500 taps. They are meant to run a airbrush art sprayer. Not enough cfms for use in the maple industry. Unless your mainline is under 100' long.