Request: Compressor setup for dummies

[SouthernSharktoothDiver]

Hey everybody,
My normal fill guy has proven himself to a rather incorrigible screw up, with multiple bad fills (filling a 3000 psi tank to 4000 psi, putting water in tanks) across a few months, and got pissy with me when I asked for an explanation, so I'm done going to him. Next cheapest guy in the area (who does seem much safer/more reliable) charges $10/fill, vs. $5 with the screw up. That's just got me wondering, let's say I wanted to set up my own compressor and do my own fills for myself and my cousin, what's my cost look like? I'm almost certain it's not affordable, but I'm curious.

I like the look of the Max-Air 35 electric, which just at base seems to cost $3670. 500 hour service kit costs $290. What other maintenance costs am I missing? It can fill an AL-80 in about half an hour, so every 500 service equates 1000 tanks, 10,000 dollars saved, for $290 in maintenance, which would be a good deal, but I assume there's other forms of maintenance I don't know about, and other setup costs as well.

So, numbers game, what am I looking at here? Given a price of $10/fill, and assuming I fill 40-80 tanks/year, would I ever break even? Assume for the moment my time has no value, just because time cost is more of a personal decision and hard to factor in. I'll do that part on my own lol. So does anyone have a good cost breakdown for owning and operating this compressor or one like it?

 

[rhwestfall]

It is never is economically advantageous.... It is the convenience factor.

Additional costs: filters (breathing air), oil changes, electric costs, air test(s) [annual?]

 

[SouthernSharktoothDiver]

How much does all that cost? Because there’s obviously a way to do it at a gain, given that shops sell air at profit, so I’m just curious what the balance is. For example, I suspect the thing needs a filter change on a time basis, not a fill basis, so that would cost you for filling few tanks in a span of time. Is that correct?

 

[Edward3c]

How much does all that cost? Because there’s obviously a way to do it at a gain, given that shops sell air at profit, so I’m just curious what the balance is. For example, I suspect the thing needs a filter change on a time basis, not a fill basis, so that would cost you for filling few tanks in a span of time. Is that correct?

Not true that shops sell fills at a profit, for some it is as a lost leader to get customers into the shop.

After nearly 400 fills it’s around £13 a fill. But I don’t need to travel to a dive shop at 25ml each way. It is more convenient and I sometimes take it to dive sites and fill there.

 

[InWay2Deep]

$2,000 - Knockoff Coltri MCH6 220v via ebay
$40/filter every 10 hrs
$90 for oil, should last a few years.
$100 for the proper fill whip/adapter (came with some crap for paintballs and a crap filter)

That above will fill an AL80 in about 30 minutes.

That's what I roughly spent to fill tanks at home. Of course I added on more things like a cart for the compressor, couple bank tanks, auto condensate drain (DYI version from aliexpress), double fill whips so my SM tanks are balanced and a bunch of quick disconnects, but all that is more convenience related stuff than necessary. Am I saving money? Probably not, but I did it so I could refill my Rebreather Bottles at home (I was chewing up drive gas) and 2L O2 bottle at the LDS was $40/pop and air was $10/pop and it was a 1hr round trip. I also make my own TriMIx at home now which closest shop doing that is 2hrs away. So was it 'worth it' for me? You better believe it. I'd rather pittle around in the garage filling tanks than driving hours every week just to get fills.

 

[SouthernSharktoothDiver]

@Edward3c I wondered about that, but at least the shops I’ve been to, using it as a loss leader doesn’t make a ton of sense. For example, the fill shop I have the most experience with is in a college town. They sell most of their merchandise to kids fresh out of OW, and then mostly just do business in fills is what they told me. That being said, for some shops, I’m sure you’re right.

@InWay2Deep ok, so let me see if I’ve got my math right. $40 every ten hours + oil, which js fairly negligible, are your only recurring costs except electricity. That means your operating costs are $2/tank in filters, plus lets say another dollar/tank in electricity and oil. Are there any other recurring costs? Because otherwise that setup would save me $7/tank, even ignoring drive time and gas money. Sure it needs some kind of biannual maintainence or something, right?

 

[rjack321]

I like the look of the Max-Air 35 electric, which just at base seems to cost $3670. 500 hour service kit costs $290. What other maintenance costs am I missing? It can fill an AL-80 in about half an hour, so every 500 service equates 1000 tanks, 10,000 dollars saved, for $290 in maintenance, which would be a good deal, but I assume there's other forms of maintenance I don't know about, and other setup costs as well.

If that max-air actually lasts 500 hrs that would be a relatively "long lived" one
You omitted that the filter on that unit is very marginal and you really need to have a 2nd filter if you want to reliably produce breathable air.

Filters you completely forgot filters
And oil is not negligible
and air testing.

And that you'll be baby sitting that compressor constantly fiddling with the condensate drains every 15mins.

Stop trying to "save money" here it's a fool's errand. Plus a good way to end up with something like lipid pneumonia

 

[Agro]

Do not buy a Coltri MCH6. In the beginning it's cheap, after a few hours it destroys itself and becomes very expensive. Not to mention your anger.

 

[InWay2Deep]

@InWay2Deep ok, so let me see if I’ve got my math right. $40 every ten hours + oil, which js fairly negligible, are your only recurring costs except electricity. That means your operating costs are $2/tank in filters, plus lets say another dollar/tank in electricity and oil. Are there any other recurring costs? Because otherwise that setup would save me $7/tank, even ignoring drive time and gas money. Sure it needs some kind of biannual maintainence or something, right?

For now yea. There will be rebuild cost down the road and the filter stack/separator will need replacing eventually (they are just like scuba tanks but nobody is going to hydro it). Ill tell you right now, if you are thinking that in the long run you will save $$, you won't. Everyone that has a compressor that I know has ongoing maintenance cost that outweigh the cost of the fill. Our local dive shops run air fills at a loss so I'm told. Currently a lot of fire houses are converting to 6000 psi composite SCBA tanks and as a result have to upgrade their fill stations/compressors, you might get a deal on an older compressor that might just need a rebuild/new motor for not a lot of $$.

Just remember that blowing oil in your SCUBA tank just once will require a tumble and O2 clean if you are using NITROX.

 

[rjack321]

For now yea. There will be rebuild cost down the road and the filter stack/separator will need replacing eventually

That compressor is functionally disposable and will never last long enough to wear out the filter stack