Tower of Power - Everything a bench should be...

[Mouse]

Getting my new bench together. Here is a picture of the frame, air box (Tower of Power) and air box cap.

The air box is upside down in the photo, to show the intake and exhaust holes. The cap has an exhaust hole. Hopefully, i will be able to exhaust air through the top during intake mode, and not the bottom.



The air box goes inside the frame. To reverse air flow, it is moved from one side of frame to the other. The air is pushed/pulled through a single hole in the bottom of the frame.



The air box cap and plumbing (bottom) is in place. This setup can use either the Flow Performance flow element and bench receptacle system, or a settling chamber and flow element, or a an orifice setup can be placed in the frame.

There is a 3" outlet in the pipe leading out of the frame for a test pressure adjustment bleed valve.




A Flow Performance FE2.5m flow element and the FR4b receptacle in place. Notice the gap behind the bench surface for C clamps and other fasteners for locating your test piece.

The air box has 3 valves that allow 2 motors at a time to run without pulling air through the other unused motors.

Hopefully, I will get 500 cfm through this thing with 8 SurplusCenter.com #16-1234 motors.

The foot print for this bench is 2'x2'.

[larrycavan]

John,

At last...the drawings are coming to life! Looks like a good start John...post some test results...

Larry C

[Mousehouse1]

John the bench looks good. Keep us posted on your progress.

[Nick]

It looks like you put a lot of thought into this one.
I like the way you are changing air flow directions.

Good work

Nick

[Mouse]

After installing all the motors in the tower, it looks pretty cramped for space in the exhaust side. This may restrict flow. I may have to exhaust this side both from the top and bottom for satisfactory flow. I don't really wantr to exhaust out the bottom because I don't know which way to direct the exhaust so that it won't create problems, like becoming a leaf blower inside my shop.

[larrycavan]

[Thomas Vaught]

The SF 1200 bench has the motors mounted at the very bottom of the bench facing upward. Not much space there yet the motors exhaust just fine. I would try it before doing a second hole.

Tom V.

[Mouse]

Preliminary testing of the TP (Tower of Power) flow bench using a Flow Performance FE2.5m flow element and an FR4b bench receptacle and SurplusCenter.com #16-1234 motors:

All figures are at 28"wc

2 motors....180 SCFM
4 motors....340 SCFM
6 motors....485 SCFM
8 motors....560 SCFM

This is with a single exhaust outlet at the top. I will try another exhaust on the bottom also.
This is also with a 3" pipe leading down from the TP. Since a 4" Y will not fit inside the 2' width of the bench, I will try to cut two 4" Ls and glue them back together to make a more compact 4" Y so that I can use a 4" down pipe from the TP.

Comments:

The built in valves work great. The whole thing is surprisingly quiet.

Works well with a 30 amp 220 volt dryer circuit.



John

[Thomas Vaught]

Notice the following?

All figures are at 28"wc

1 motor roughly 100 SCFM

2 motors....180 SCFM (or 90% of flow)
4 motors....340 SCFM (or 95% of flow)
6 motors....485 SCFM (or 81% of flow)
8 motors....560 SCFM (or 70% of flow)

As you add motors to the equation the actual flow will drop more and more and you get less average flow out of each motor.

Tom V.

[Mouse]

Yes, internal restrictions probably.

[Thomas Vaught]

John, can you repost your internal drawing of the motor box for the Tower of Power?

Thanks

Tom V.

[Mouse]

The only changes sp far are that I am exhausting out the top instead of the bottom while in intake mode. Keeps the "leaf blower" effect from dusting my shop floor at inconvenient times. I also have a valve every two motors (I have 8 motors in actual build).

John

[Thomas Vaught]

Thanks. I am still looking at the horizontal check valve orientation for a friends bench. If he wanted to buy the check valves (capable of enough flow for 6 motors flowing - Bottom check valve has to support flow of the 6 motors above it).

Please pm me with a price.

Thanks

Tom V.

[Mouse]

The Tower of Power hit 610 SCFM @ 28" today! This was venting all the exhaust out the top and none through the bottom.

Specs:
8 SurplusCenter.com #16-1234 vacuum motors
Flow Performance FE2.5m flow element
Flow Performance FR4b bench recptacle
30 amp 220 volt cloths dryer circuit
3 internal check valves, every two motors.

I placed a 4" down pipe and Y in place of the previous 3" down pipe and Y from the air box.
I wired the motors in parallel so that I could use household 20 amp switches instead of finding 220 volt switches.

John

[Thomas Vaught]

Nice work.

The FP FE2.5m is a "Hot Wire" or a Pitot tube
element?

Tom V.