Scubapro chrome plated brass regulators...

[dead dog]

Plumbing the vacuum cleaner to the flowmeter. Just came up with this, modified my vacuum cleaners suction release collar and it give me a range of 5-25 CFM on the meter.

Next I’m going to try a gate valve teed-off the suction line, instead of a ball valve. Hoping for smother control and better range.

View attachment 580926

Your workshop is just like mine, in the living room. lol

 

[Couv]

I don't understand enough about it (electric junk) to smile or frown. I actually thought the dimmer a) Would not slow the motor down. b) If it did, it would quickly damage the motor. c) The dimmer itself might overheat as it's made to dim lights as opposed to a fan speed switch designed to slow down a motor. I am truly flummoxed because I was given to understand one would have to change the frequency to change the motor speed. Again, if it works, it works-don't try to tell a bumble bee he cannot fly.

I think I'll plumb my system up the same way, except put a choke (quarter turn ball valve) in line with the vacuum pipe but downstream of the other valve. By varying the position of the two valves it is my hope to exactly control the amount of vacuum. @rsingler you've probably operated a decompression chamber hundreds of times-you remember the vent phase right?

 

[Open Ocean Diver]

Nothing like tinkering on the couch in front of the TV. Lol

 

[Open Ocean Diver]

I don't understand enough about it (electric junk) to smile or frown. I actually thought the dimmer a) Would not slow the motor down. b) If it did, it would quickly damage the motor. c) The dimmer itself might overheat as it's made to dim lights as opposed to a fan speed switch designed to slow down a motor. I am truly flummoxed because I was given to understand one would have to change the frequency to change the motor speed. Again, if it works, it works-don't try to tell a bumble bee he cannot fly.

I think I'll plumb my system up the same way, except put a choke (quarter turn ball valve) in line with the vacuum pipe but downstream of the other valve. By varying the position of the two valves it is my hope to exactly control the amount of vacuum. @rsingler you've probably operated a decompression chamber hundreds of times-you remember the vent phase right?

I think the bleed method as @rsingler points out works best, choking the vacuum will run the motor hot and depending on the make you have may trip it electronically in overload.

Vacuum motors mostly are universal motors meaning you could actually run them on AC or DC. So for Dc motors changing the armature voltage you vary the speed. For a three phase AC motor you want to very the frequency and the voltage in order to maintain torque at varying speeds. If you only changes the voltage in this type of motor you would loose torque.

 

[Open Ocean Diver]

I don't understand enough about it (electric junk) to smile or frown. I actually thought the dimmer a) Would not slow the motor down. b) If it did, it would quickly damage the motor. c) The dimmer itself might overheat as it's made to dim lights as opposed to a fan speed switch designed to slow down a motor. I am truly flummoxed because I was given to understand one would have to change the frequency to change the motor speed. Again, if it works, it works-don't try to tell a bumble bee he cannot fly.

I think I'll plumb my system up the same way, except put a choke (quarter turn ball valve) in line with the vacuum pipe but downstream of the other valve.

I miss read was thinking up stream. Interesting experiment, can’t wait to here about your findings.

 

[Open Ocean Diver]

Your workshop is just like mine, in the living room. lol

Nothing like tinkering on the couch in front of the TV. Lol

 

[Couv]

I miss read was thinking up stream. Interesting experiment, can’t wait to here about your findings.

Actually, you probably did not miss read. The vacumm is furthest downstream while the regulator if furthest upstream. However, in light of this:

..choking the vacuum will run the motor hot and depending on the make you have may trip it electronically in overload.

I'll probably reverse the order of the valves-but operate them in the same manner. That way, I hope to control the flow to the rotameter without starving the vacuum cleaner.

 

[lexvil]

Regulator, roto, T with ball valve the vac pump is how I would do it, break the vacuum with the ball valve.

 

[Open Ocean Diver]

With my 1 inch ball valve fully opened I can get the Roto metre to go to zero and then up to maximum of 25 CFM and more with my upright vac. But the ball valve is a bit hard to open and close in a precise manner. Without the ball valve I noticed I could feather with my hand over the tee opening and basically modulate the CFM to anywhere I want it to be. So I ordered one of these to give it a try. The reviews say it’s a smooth and easy operator.

 

[Open Ocean Diver]

Testing my Atomic first stage this rainy Sunday morning...

Tank pressure 1400, IP 135 locked up. G250 connected, turned on the micro vacuum pump set it to 3 SCFH and watched the IP drop and quickly recovers 132, inhalation effort .7 perfect at that moment. Just after recovery the IP will drop again inhalation goes up IP will then recover 132 and inhalation effort goes back to .7, and the processes keeps repeating itself.

Removed the filter no help, switch the tank for one filled to 2800 no help.

Any thoughts on what would cause this? Hope my explanation makes sense.

I did see green corrosion on the filter about a month ago cleaned it and it seem to work fine, this it something new but still maybe related to corrosion inside?

Thanks,