Help with an idea for air-bearing pump

[Paul Ebert]

I may need to find an alternative compressed air source for the air-bearing in my DIY tonearm as my current compressor is starting to make an odd noise (and it's only 3 months old!).

My requirements are for 0.012 scfm at about 40 psi.

When I was looking for my current compressor, I looked all over the place for an affordable and quiet pump. I also wanted it to be oilless, so I didn't have to buy filters all of the time. What I found seemed pretty much the only game in town besides going with compressed air, which would have been costly.

One idea I had, but didn't pursue, was using a refrigerator or freezer compressor. Not the typical application for such, but I wonder if it would work. Does anyone know anything about them? In particular, what their output (volume and pressure) is?

Thanks.

Paul Ebert

[Havoc]

A fridge or freezer compressor might do the trick. But they are not exactly oil-less. Also quite some fluctuations on the output (pulsed air) so you would need a buffer. And they can get quite hot when running like you intend. No idea about volume or pressure delivery.

Take a look at artist supply shops for them. They are used for airbrush work, and come then complete with filter and buffer tank.

[Paul Ebert]

Originally posted by Havoc
A fridge or freezer compressor might do the trick. But they are not exactly oil-less. Also quite some fluctuations on the output (pulsed air) so you would need a buffer. And they can get quite hot when running like you intend. No idea about volume or pressure delivery.

Take a look at artist supply shops for them. They are used for airbrush work, and come then complete with filter and buffer tank.

Thanks for the reply. So, there is some sort of oil or lubrication in the coolant gas? I guess that would make sense. Given that, the only benefit I can see is, maybe, cost.

I've been looking at airbrush compressors. Suitable ones tend to be upwards of $500 or so. Another option is compressors for dental work. These are very quiet and reliable, but are $800 and up. They all use oil. Perhaps I should ask my (few) dentist friends to keep an eye open for a used one for me.

Pulsed air is not a problem as I already have a buffer tank and regulator/filter.

Thanks, again.

[slowmotion]

Hi ,

I've been using an aquarium pump, no oil

cheers

[Paul Ebert]

Originally posted by slowmotion
Hi ,

I've been using an aquarium pump, no oil

cheers

This would be great if it met my requirements for pressure (40 psi) and flow (0.012 scfm). Do you happen to know these specifications for your pump? My impression has been that aquarium pumps don't put out much pressure. If yours is suitable, could you please let me know its make and model number? If the flow was too low, I believe I could use multiple pumps to make up for it.

Thanks!

Paul

[slowmotion]

Originally posted by Paul Ebert



This would be great if it met my requirements for pressure (40 psi) and flow (0.012 scfm). Do you happen to know these specifications for your pump? My impression has been that aquarium pumps don't put out much pressure. If yours is suitable, could you please let me know its make and model number? If the flow was too low, I believe I could use multiple pumps to make up for it.

Thanks!

Paul

Hi Paul

I don't know pressure & flow, it says

Medo Compressor, 46W
Nitto Kohki Co ltd
No 40604929,

that's all, plenty pressure for my arm, tho,


Sorry I can't be more helpful

cheers

[Paul Ebert]

Originally posted by slowmotion


Hi Paul

I don't know pressure & flow, it says

Medo Compressor, 46W
Nitto Kohki Co ltd
No 40604929,

that's all, plenty pressure for my arm, tho,


Sorry I can't be more helpful

cheers

Thanks for checking for me, but I looked it up on the web (http://www.medousa.com) and it appears that it puts out less than 5 psig. Medo makes a compressor that puts out 42 psig, but its flow at that pressure is very small. They are quite quiet, though. Being linear piston pumps, I would also assume that they would be very reliable. I'll keep them in mind, should my current pump fail.

Paul

[slowmotion]

Hi Paul

Thanks for the link. My pump is more than 20 years old,
so can't find it at the Medo pages, looks a bit like this, tho:



Hmm , no picture? well , doesn't matter,
hope you find a pump that works for you

cheers

[fdegrove]

Hi,

Medo Compressor, 46W

Wasn't that the same pump as used by Air Tangent?

You can always run one or two or even more of those in //, I have mine in another room even though it's pretty quiet.

Cheers,

[dwk123]

I've been looking for a compressor as well. I have an ET2 that I'd like tur run at a higher pressure, and I also have the platter air-bearing from a Maplenoll Athena that I'm hoping to use in a semi-homebrew table.

From everything I can tell, the Silent airbrush compressors are more or less the same principle as fridge compressors, although I don't know whether both are oil-free (I assume that the airbrush units are, but it's been a while since I've looked). I haven't been able to bring myself to drop 4-500 on an airbrush compressor, so I've been hoping to come across someone that has tried the the fridge compressor route. With a cheap 5-10 gal air storage tank to serve as a smoothing resevoir, I would think they'd work well.

The only downside is that you'd have to fabricate the connections, since you'd probably have just bare pipe-ends if you used a pulled fridge unit.