Buying a compressor

[pescador775]

The compressor is a belt driven Walter Kidde 4 stage block with Briggs 5 hp engine. The drive adapter with pulley is custom made. Filtration is a Kidde condenser plus a copy of the American Bristol filter. There are back pressure and relief valves in line. The gauges are hrs/tach and oil pressure (the Kidde is a pressurized system). The frame is home made from steel water pipe. The engine is not big enough to drive the Kidde at full speed but I like it for various other reasons. In order to facilitate starting there is a clutch consisting of a bearing which is raised and lowered by a knob. Only the clutch guide is visible in the photo. Output is 4.1 cfm (hot fill, not liquid cooled).

Thats a great looking compressor! Is that a Walter Kidde or Cornelious?

I'm watching govliquidation but, no luck as of yet.

 

[Cheekymonkey]

What is one looking to spend on an uber basic compressor for home use, not sure about the electric or gas, what are the pricing differences, I'm another compressor noob looking for info.

 

[cobaltblue]

I just went through the research and purchase phase. Long and short of what I found out is this. There are some great compressors out there and there is a pretty large swing in pricing. For me, I didn't look at used. It's not that money is no object, it's just that I only have one set of lungs. Not to mention the fact that some of the rebuild numbers I heard could make a used compressor "like new" priced pretty quickly. Along with that, I figured this was something that I was going to buy once, use for years and years, and even after that, I could recoup a pretty large chunk of my initial purchase price. I didn't see any financial benefit in long term cost of ownership in buying used compared to new. Next thing I looked at was what company was going to be there in five and ten years to service this thing and get me parts. After that, the decision was pretty easy. Looking at all that information, I found there were only a few companies which I would consider. I did look at some of the less expensive compressors but I figured that the cost of ownership would end up being higher, mostly when it came time to sell/upgrade. The final decision was looking at the compressors I found that some of the competitors of Bauer were using Bauer parts. What that told me was Bauer was the benchmark company. It seemed to me that if these companies are using Bauer filters and other Bauer parts, Bauer is probably the best/leader in compressors. Decision made. I purchased a Junior II gas powered.

I went with gas so I could also use it one my boat. I am building a "stand" to hook up the compressor and run off an electric motor when not on my boat.

Through this whole process, Bauer was wonderful to deal with. They answer the phone and want the customer to be happy. The compressor was damaged by FedEx and Bauer covered it. Why, they wanted me to be a happy customer. So like my earlier post said, find what Bauer you want and buy it.

As far as all the other stuff, for an additional $1000 or so I should be able to mix all my own gases and be realatively self sufficent. So as for a $5000 budget, I'm going to just about hit that. I may go over by a few hundred dollars. The compressor was $4K and some change. But what the heck, I dive and boat, so really it's only like 5 boat dollars or about 10 scuba dollars.

 

[Meister481]

I'm in the process of building a system to pp blend/fill anything needed for tech diving. There are 2 of us making the purchases so it's easier to do. I have: Bauer juniorII, haskel ag60 (not O2 cleaned). 2nd person has fill whip, k bottles, tumbler, cylinder inspection stuff. We're not going to boost O2, too risky. We will boost He and argon. The cost is below 5k, but we're going to take a mixing class before we do the mixing.

I got my comp from ebay, it didn't sell so I called the bidder after the auction closed and made an offer. Got a 2000 electric model cheap, low useage.

 

[rcontrera]

The final decision was looking at the compressors I found that some of the competitors of Bauer were using Bauer parts. What that told me was Bauer was the benchmark company. It seemed to me that if these companies are using Bauer filters and other Bauer parts, Bauer is probably the best/leader in compressors.

That is a really hard thing to go by since there are so few real manufacturers of compact portable compressors. Basically, you have Bauer and ColtriSub in the compact business. And between them, ColtriSub has more private label "manufacturers" using their machines. I think in the US there are 21 or 22 different compressor companies selling ColtriSub compressors under their own model numbers or names.

And as far as who uses what from whom, Bauer sells a couple of parts to Coltri Sub and Coltri sells stuff to Bauer. It is a tiny, incestuous industry. It doesn't really mean a thing.

I have sold both for some time now and, while the profit is a whole lot bigger on the Bauer, I have found the little Coltri (2000 model or newer) is a great little machine. Plus, parts are a whole bunch easier and cheaper to get. Oh, and if you decide to pump nitrox through the compressor, Coltri doesn't void your warranty like Bauer does.

Just a thought.

 

[Cheekymonkey]

Wow I had no idea a new compressor could be found in the 4000 dollar range, what kind of fill times are you talking for one of those.

 

[rcontrera]

Bauer Junior II gasoline - $4251
ColtriSub MCH6 - $3090

Both take approximately 15-20 minutes to fill a standard 80

 

[Slipstrm]

I recomend Bauer as well.
Get and Read the Oxygen Hackers Companion by Vance Harlow.
http://www.airspeedpress.com/newoxyhacker.html
Read the articly by O.C.Diver at the DecoStop,its very good info regarding the care and feeding of compressors
http://thedecostop.com/forums/showthread.php?t=9756&highlight=filtration
Keep in mind High Pressure air is very dangerous!

 

[Cheekymonkey]

As for setting them up how mobile are these, are they back porch safe type thing?

 

[rcontrera]

Depends on the machine and what comes with it. If you unpack one of my little guys, you have to add the oil to the compressor (included) and the plug to the cord if electric or gas and oil to the engine if gasoline driven. The really hard part (at least for divers) is reading the safety instructions in the manual. Seems like most divers don't like to read instructions until something breaks.

Now, all that said, you should be able to start pumping air within a half hour of unpacking the compressor. The little ones weighs less than 100 pounds so can be moved fairly easily to where ever you need them.

Oh, and a compressor is only as safe as the operator so ...
READ THE INSTRUCTIONS!! :rtfm: