New toy...

[camerone]

New to me, anyway... thanks go out to MattWave and Laura for vouching for the fact that I can pay my bills

Once I finish assembly, repack the filter, change the oil, replace the CO/Humidity disc, and add an hour meter, I think it's the last piece of self-sufficiency I think I need, other than the occasional 'sorb tub, trip to Praxair, or rebuild kit...

[Jenbowes]

Neat!

Um, what is it?

[cardiver]

Neat!

Um, what is it?

It's a compressor.......

[Jenbowes]

Neat!

Um, what is it?

It's a compressor.......

Even NEATER!

[lizard0924]

Wow, that is cool. Congrats!

But please don't let my dive buddy read this thread. I've tried my best to convince him that people don't actually have their own compressors at home, that it's just an urban dive legend. If he sees this, my car will surely be relegated to the driveway.

[camerone]

Wow, that is cool. Congrats!

But please don't let my dive buddy read this thread. I've tried my best to convince him that people don't actually have their own compressors at home, that it's just an urban dive legend. If he sees this, my car will surely be relegated to the driveway.

Funny. I need to clean out my garage, too, to get rid of some of the junk and make more room to be able to set up or work on the dive gear. One of my thoughts was to just kick Heidi's car out of the garage The compressor setup is going to take some thinking to get right. It's got a nitrox stick on it, but the only nitrox worth the bother of mixing is 50%, which I can't pump through the compressor (oil lube) so I need to figure out a good way to set up enough space for easy PP blending.

Sigh...you buy gear to save time, and it ends up already eating more time. Life's rough

[CaptnJack]

Is that a gas powered Coltri? I am guessing you bought that from Alan in Marysville?

[camerone]

Is that a gas powered Coltri? I am guessing you bought that from Alan in Marysville?

Yup, and yup. I'd been searching for a while for a Rix SA-3e, but they're hard to find - the SA-6 size is more popular, and people don't like to let them go. In the end, this deal was really too good to pass by, and he definitely knows how to take care of his stuff. The gas engine saves me the trouble of having to run some electrical in my garage to handle a 220V plug as well, although I actually don't mind electrical work. Plumbing, I hate, but electrical is no biggie. I'm hoping that it should also make it perfect for heading out the Neah Bay and more remote long weekends. (Ok, with the rebreather, it's almost a nonevent, but still...)

Alan and my paths have crossed before, but somehow we never met up. Turns out that he had one of my spare lift bags on his boat for almost a year without me realizing. We figured it out yesterday, which was kind of funny.

-c

[Paulicarp]

how do you vent the exhaust?

[camerone]

Pull it to the edge of the garage, and leave the door open? I actually have a shed that I was thinking of converting to a fill shack - it's small, but it would be plenty nice for what I want to do.

It's not sitting on a cart in the picture, but I have one for it waiting. The thing is surprisingly light - 80-ish pounds - easy enough to toss in the car alone, so it's perfectly liftable by one person, and it rolls easily. The intake has a 6 foot feeder hose with a filter on the far end, which is plenty far away from the motor, and there's a CO monitor plug in the output stream, just in case.

[CaptnJack]

Glad you got to meet Alan and take his compressor off his hands.

Some free get-what-you-paid-for-them suggestions. I can't see the exact plumbing right now some of these may already exist...
Move the humidity disk to after the tiny on compressor filter but before the 2nd stack
Get some 10/20/30% humidity disks
Change the 1st filter when the moisture content is 20% or greater
Change the 2nd filter every 60-70 hours (it won't be used up but has somewhat limited shelf life)
Be sure to run a triplex cartridge in the 2nd canister (hopcalite catalyst)
Add an extra fan (or 2) blowing on the intercoolers and away from the remote intake

Don't trust the 50ppm spot CO detector for anything. That is 25x the maximum level of CO you'd want to breath - which should be <zero>. New gas standards in firefighting and elsewhere are recommending a CO limit of 2ppm since CO seems to be a significant agent spuring in heart attacks. Since its gas powered you may want to consider buying a portable CO monitor as well.

Happy diving mate!

[camerone]

Thanks for the tips! I think that mostly aligns with my plans:

Some free get-what-you-paid-for-them suggestions. I can't see the exact plumbing right now some of these may already exist...

Move the humidity disk to after the tiny on compressor filter but before the 2nd stack
Get some 10/20/30% humidity disks
Change the 1st filter when the moisture content is 20% or greater
Change the 2nd filter every 60-70 hours (it won't be used up but has somewhat limited shelf life)

Yeah, it ran with the tiny filter empty, and just the second filter being used, which explains why it's post-second filter. It's self-pack, which I prefer, and I have materials to re-pack it, including hopcalite. The plan was to replace the primary filter and turn the secondary into a hyperfilter to pump OCA for blending.

That primary is really tiny with a short life, but at least we're not rotting in the swamps of Florida. Also, it's got a priority valve on the output of the second filter, so the bank will always stay reasonably pressurized (read "dry") and there should be pretty good dwell time.

Add an extra fan (or 2) blowing on the intercoolers and away from the remote intake

I've got a few in the garage to plug in nearby. I also have an IR thermometer and specs for the ambient rise on each stage, so at least periodically, I'll be able to keep things in check. Coltri makes a fairly inexpensive kit to measure the interstage pressures, too, which is usually a indicator of wear on the pistons and should also provide a clue towards blow-by worries.

Don't trust the 50ppm spot CO detector for anything. That is 25x the maximum level of CO you'd want to breath - which should be <zero>. New gas standards in firefighting and elsewhere are recommending a CO limit of 2ppm since CO seems to be a significant agent spuring in heart attacks. Since its gas powered you may want to consider buying a portable CO monitor as well.

Happy diving mate!

Yeah - same problem with the stick-on ones we use in a lot of airplane cockpits. By the time you get a headache, the dot starts to light up.

I need to fix the hour meter on the unit, which is its only flaw and is pretty easily replaced...and I am going to plumb in a big liquid filled 4" pressure gauge I have onto the output of the second filter, as the one on the unit vibrates too much to be anything than "you're in the neighborhood of XXX psi," and that doesn't cut it when you're mixing into 13 cf bottles.

Any recommendations on air quality testing labs/kits? I want to send a couple of samples off when I get this thing running, and again after it runs for a while.

-C

[CaptnJack]

Personally I run a 13x + AC handpacked primary cartridge (about a Bauer P0 size) and it lasts between 10 and 24hrs depending on the season. I change that when the produced gas has >20% humidity which happens very very suddenly, within 1 tank. At that point the AC bed in the primary filter will be effectively saturated and gaseous hydrocarbon vapors (if present) could pass.

I then use a store bought triplex cartidge for polishing ($45 lasts me 13,000cf). I change this on rated volume even though it doesn't work very hard. My conceptual idea is to always have a well functioning 13x, AC, and hopcalite bed downstream of the little filter that is supposedly already making suitable gas (but which has sudden breakthrough).

I don't technically have a hyperfilter although my gas meets OCA standards (which are actually fairly easy to meet). In general I guess I am alot less concerned about oil mist and much more concerned about gaseous vapors and CO, either produced in situ from dieseling of oil or from a car nearby. Hence the triplex filter as a "backup/polisher" vs. just 13x in a hyperfilter.

Anyway that's my approach and it seems to be well accepted by the more experienced compressor folks I've explained it to.

For testing you might try TRI
http://www.airtesting.com/

or Analytical Chemists in San Diego
http://www.airanalysis.com/

You want a lab participating in the compressed air proficiency testing (CAPT) program which I think is a Navy deal. You can read up on it @ TDS. Pretty much anything Peter Moulday(sp?) aka Swampdiver writes about is air quality related and worth reading.

The UW school of occupational health has a lab, but it not worth bringing a sample there.