Fein Vacs

[tracys]

Has anyone measured what they are pulling in Hg with 2 Fein vacs?

[Gary Campbell]

Tracy...
The design specs for the Turbo lll is 99 inH20. That converts to 7 1/4 inHg. These are the design specs and can be very seldom delivered in the real world. Hoses, case leaks and adjustments for altitude would all reduce the actual vacuum delivered.

It is my opinion that the best that you could get, measured at the plenum would be 6.5 inHg at sea level. How well you attended to leaks in your distribution system and plenum could reduce this to 6 inHg. Your altitude will reduce it further.

Hope this helps

[cabnet636]

when i had mine setup i got 7" on the guage

jim

[gabriel_mckeagney]

Well I run 4 fein vacs on my prs, and have after about 2 years service, just paid to have all 4 motors replaced at $260 a each replacement.
Still, I recon that is is still a cheap vac solution overall, and better on elecricity that running my 3ph vac. Quiter, which is a big plus.

Funny how all of them clapped out with in a 6 month period. I guess I am a medium hard user. Best tip I got from the service guys is to blow out around the motor often and give them good ventelation.

Gabriel McKeagney

[jim_vv]

I get 7" HG with two. I usually use only one on a 2' x 4' zone.

[curtiss]

So 7" in of Hg would mean how many psi holding the work down ??

[Brady Watson]

You can run 100 Fein T3s and you'll still only get about 7 Hg" of suction...BUT you'll have a whole lot of CFM that will help maintain that 7 Hg" when you cut thru your parts and open up the kerf to vacuum leakage.

Here's a little practical 'Vacuum Math' for us woodworkers:

ALL of these are EQUAL: 1 Atmosphere = 14.7 psi = 29.92 Hg"

So...If my Fein T3 puts out 7 Hg", and we want to figure out how much downforce we will have per square inch:

7 Hg" / 29.92 Hg" = 0.23395

14.7 psi X 0.23395 = 3.44 pounds per square inch downforce

-B

[harryball]

Mine pull about 5.5 to 6.5 on any given project. I've found if it drops below 3.5 it's time to stop for most applications, or be very careful. Adding gasket to the heads of the machines to seal the tank and wrapping the seams in the hoses will help. if you take a stick of incense and burn it placing the smoke around joints you will quickly find leaks. Of course while burning incense you have to friz your hair (if you have any) and wear a tie-dye Tshirt.

/RB

[Gary Campbell]

Robert....
I think the 2 Jim's bought their gauges from the same place I used to get snowmobile speedometers from ! :D

[tracys]

I have 2 regen blowers piped in pvc with 4 - 2' x 4' zones. I have a 3 hp and a 2 1/2 hp blower I can use them in tandem or independent. I get just under 5 Hg in either situation. The sheets seem to hold better if I leave 2 zones open and mask off the unused areas. Now I am thinking of replacing one of the blowers with a 10 hp. Right now if I have a 24" x 48" plywood with any warp at all I can't hold it down. From your responses the 2 feins are pulling better. Is looking at a 10 hp the way to go?

[Gary Campbell]

Tracy...
My quick response would be yes, but I would want to take a look at the specs first. IF you have more vacuum it will surely pull your sheets down better. That said, if you dont have enough CFM to hold the vacuum when cutting, then your upgrade could be a down grade.

Could you post the specs of the 10hp?

[tracys]

Gary,
I am supposed to get a quote on the blower tomorrow. I will post the specs. I am just starting to figure these blowers out. Is there a big difference in vacuum from 5 Hg to 7 Hg. I am not sure of the ration of increase.