Miniature High Pressure Air Compressor for Tank Refills??

[JKR]

FYI to those posting and reading this thread, there is a quite healthy discussion and debate going on at mcarterbrown.com.

[bbotts77]

This is definitely something I would be interested in; especially if it was owner-serviceable. I also think the price range you've mentioned is fair.

[GoatBoy]

I haven't read the whole thread, but what really interests me is how the filter and moisture management system are done.

As mentioned elsewhere, if I really wanted HPA at home, I could go buy one of those airgun pumps that go up to something like 3300PSI... But I always wonder about how to keep the air clean and dry.


Preferentially, I'd like a device that I could use at a field to top off crappy fills. HPA is fairly widely available, but GOOD HPA fills... are more scarce. Boosters aren't common.


Of course when at the field, the conditions for dirt and humidity will vary pretty wildly.

[jade_monkey07]

i would be in too

[MoeMag]

I like it. I would also be worried about having dry air. Then, just a side thought... 3am burst disk.

[SR_matt]

I like it. I would also be worried about having dry air. Then, just a side thought... 3am burst disk.

even 3k's have a 5k disk on it so you shouldnt have an issue even if the system failed to cut off (kind of doubt tom would let something out that wasnt super redundant with safety on that)

-matt

[JKR]

Wish I had one right now! Got a game on Saturday and need my tank topped off. Hope this project becomes reality soon! :)

[skipdogg]

any updates? hows the R&D going?

[ArmyEngineer]

I don't know much about air compression systems, but just thinking about the moisture problem, came to a couple of conclusions.

Here is some data on absolute humidity. Notice the saturation pressure at room temperature. http://www.engineeringtoolbox.com/hu...air-d_686.html

And see: http://www.tis-gdv.de/tis_e/misc/klima.htm

Don't check my math or units, this is just an approximation. :) Does it seem reasonable?
Here is a crude idea of how much air a 68 tank takes at 3000ps (we aren't dealing with an ideal gas here)i,
P1V1=P2V2
(3000)(68)=(14.1)(x)
x=14468 cu in
x=0.23 cu m

If you run the compressor inside, your temperature is probably around 20 degrees C and RH=30-40%

Thats 6.9 grams of water per m^3. So divide that by 4. You have 1.72 grams of water in your tank.

We are talking relatively small quantities of water, but still significant. Maybe one of these will work.

1. Use this on your air intake.


2. Use a cooling coil to condense the water vapor and then blow it off. I have a feeling that with the low compression rate the tank won't heat up very quickly so this probably won't work well. Maybe some of the liquid can still be collected in and blown off of a holding tank

3. Reusable desiccant cartridge. If there is a holding tank, screw the cartridge in to the outlet port after a valve. When the desiccant is saturated, close the valve and remove the cartridge. Regeneration of the cartridge could be performed around 300 degrees F. Then replace the cartridge and open the valve. Wait for saturation, repeat. (There should also be a valve after the cartridge.)

4. Semipermeable membrane dryer.

[AGD]

Compressor Update:

I have two of the three stages prototyped as of today. The second stage got up to 950 psi as planned for in the design. Third stage construction starts tomorrow.

So far so good and no problems (knock on wood).

AGD

[Beemer]

Knock.....

[Watcher]

knock

Take as long as you need

[kwood]

knock on kwood...

[Wrathbringer]

Knock once more...

I'm impressed, I was sure that this would take a lot longer but you seem to be making great progress with the compressor! I'm looking forward to seeing the working prototype

[Mavro]

I would definitely grab one of these. For those times that a little fine-tuning in the basement will save heartache on the field, waiting a day for a full tank is well worth it. Count me in for 2. I'm sure my teammates would pick a few up as well.