Air Compressors

It's been so quiet on the site, I'm willing to talk about anything.
I needed to replace my 25 year old compressor and as usual, I'll look on Kijiji to see what's available used. Some equipment is up for sale because people don't need the item anymore and deals can be found.
I picked up a Coleman Powermate 20 gallon compressor for $100 CDN. It has some good specs on it and I was specifically looking for a flow rate of around 10 cubic feet per minute. This one is a 7.1 SCFM and although it wasn't quite what I was looking for, it was small enough to run on a 15 amp circuit with a big enough tank that would work for painting the bike with my HVLP spray gun, If I took my time.
So I bought it. got it home and then tried it out. A little slow to fill the tank and I wondered. Hmmmmmm. Popped the cylinder head off and inspected. Sure enough the wobble piston has a teflon seal ring on it and the ring had a split in it. Ended up buying a replacement piston which came supplied with a new cylinder as a kit. $90 CDN later.........So now my bargain is not such a great bargain. Oh well.
Recently when I was sandblasting my cylinder sleeves I noted the air compressor was struggling again , to fill the tank. Not liking this. I knew when I bought it that it was an oil less compressor and  being old school, I really wanted a oil lubricated compressor, but then thought  I'm going to be painting and I don't want any oil mist in the supplied air. Oil less compressors have ben out for 20 odd years so I ASSUMED that things had gotten better. I shouldn't have assumed. The oil less and the oil lubricated compressors both have a 50% duty cycle, so wouldn't either one do what I wanted them to do??
So what does 50% duty cycle mean?? 1 cycle time on, then 1 cycle time off? I.E. 3 minutes on, 3 minutes off?? Or 30 minutes on, 30 minutes off?? I have no clue, but when sandblasting the cylinders I was running about 4 minutes on, 4 minutes off and I think it was a problem.

So I got pissed off at myself for buying the oil less compressor and knowing that I will be painting the bike maybe in the spring of 2025, I needed to investigate this compressor replacement again.
Shopping for a lubricated compressor nowadays, I found that 80% of the consumer compressors are oil less and only commercial units are oil lubricated. There are a handful of consumer compressors that are oil lubricated but typically they are 50 % more expensive. A new 20 gallon oil lubricated compressor will run you around $650 CDN and I didn't want to spend the money.
I went to a local tool supplier and asked about lubricated compressors and what was his suggestion. Without hesitation he says ' MAC series Makita. You can't go wrong. I don't stock them 'cause I can't sell them in this store. Nobody will pay the money."
The Makita MAC5200 has an airflow rating almost identical to the Coleman Powermate at 7.1 SCFM and it's oil lubricated. So back to Kijiji.....

Don't I find one listed and in the listing the seller notes that it keeps blowing fuses and has done so since brand new. $100 CDN. It's listed in Kingston Ontario which is a 2 hour drive away from me. I make arrangements to see it  and go the next day.
I meet up with the guy and he points out the compressor. Doesn't offer any information freely and I asked about the fuse blowing issue. He tells me that his son listed it and he knows nothing about the fuse issue. The compressor looks OK, maybe a bit dirty. So I buy it. New price for the compressor at Home Depot is $620  CDN, so for $100, I'll figure out what's wrong and fix it. Makita is a great brand and make solid tools so in the end, I should have a great compressor. Load it in the truck and drive home.
And of course the wife is along for the ride. On the way back she asks me " Why do you keep buying pieces of shit and have to fix them? Why don't you just buy new stuff and look after it? Aren't you tired of buying shit and fixing it?"
'It's a $600 compressor and if I have to put $100 into it, I'm still ahead."
So we finally get home and I get the compressor out of the back of the truck and plug it in. It fires right up and fills the tank in about 1 minute. Wow !! didn't blow a fuse , even better. Well, maybe run it a few more cycles..... Bleed off the air 5 more times and cycle fill it 5 times. Still running like a champ.
On the top of the compressor is a storage compartment and in the compartment is the owners manual with a hand written note. ""June 4 2018. $299 Tractor Supply." So now I know that it was bought new for $299 and it's 6 years old. Also in the compartment is a spool of roofing nails from a pneumatic roofing nailer and also a clip of 3 1/2" framing nails for a framing nailer. So the kid was using it for  construction. That's important and here's why.
On construction sites, the power supply is never where you want to park the compressor and usually you have to run an extension cord. This compressor has a 3 HP motor and the amp load on the motor at near full tank pressure is 14.7 amp. That's too close to the 15 amp breaker trip point and IF you run a 75  ft. extension cord of 14-2 gauge, you can add another 5 amps for current loss on the 75 ft cord. BINGO !! That's why it was blowing breakers and why the guy decided to dump the compressor. You can't have tooling blowing the breaker all the time when you're trying to make money working. Had he used a 12-2 gauge heavy duty cord, he wouldn't have had the problem, or IF HE READ THE MANUAL  on the compressor, it says right in the manual, DON"T USE EXTENSION CORDS, RUN  A LONGER AIR HOSE INSTEAD AND PARK THE COMPRESSOR AT THE RECEPTACLE.

His loss, My gain. So armed with that info, I go inside the house and explain to the wife. " That piece of shit is actually a piece of gold, and the idiot seller didn't use the right extension cord LIKE THE MANUAL SAYS TO, and that's why it kept blowing fuses. There's nothing wrong with it. "
"Well, you got lucky this time I guess" was her reply, not anything like "Aren't you a smart fella and figured it out before you bought it."

So why post the story??  I know from building a house 25 years ago, that the Electrical Code requires an increase in wire size when the circuit on a breaker is longer than 75ft. For a 15 amp circuit you have to change from 14-2 wire to 12-2 wire to reduce the resistance in the circuit. This principal also goes for extension cords when running loads near maximum circuit amperage. Just sharing information and telling a good story. Hope you all get a chuckle from this and maybe learned something. I consider a good day when I learn something new. Keeps my brain active..
Cheers,
KB

 

This was the first . Oil Less Coleman Powermate.

 

The replacement Makita MAC2500. $100 pot of gold.

There’s nothing like a good compressor story to start your day ! Way back, in a land for away, I also found myself in need of a compressor.  I needed one for framing and finishing. At the time – About $700.00 for a Campbell Hausfeld.  Similar to kawboy I started scrutinizing the classifieds.  I went to look at a 20-gallon advertised for $100.00.  It was a Campbell Hausfeld but was no gem!  The ID plate was dated 1975 so I knew it was 10 years old. The belt guard was missing as was the starting capacitor cover.  Plugged in; it wouldn’t start nor make any kind of a sound that indicated it was trying to.  So, add to the list: “Requires a new pressure switch and likely a new 2hp motor”.  I tried turning it over by hand it stopped dead at top dead center.  (Pun intended).  Undaunted, I returned home with a $50.00 air-tank.  First thing I did was remove the air-filter and found it gagged with house-paint primer.  That’s when I realized why it wouldn’t turn over past TDC.  I removed the cylinder-head and found a heavy ridge of primer at TDC.  I ended up dissembling the compressor. I put in some new bearings for about $20.00, used my favorite solvent to remove the paint ridge, ran a cyl. -hone through the bore and reassembled.  Bought a new pressure-switch for about $70.00. a new belt ($15.00) and another $30.00 for some air-couplings and a pressure-gauge.The electric motor was also full of over-spray so I figured on a new starting switch, new capacitors and probably bearings.  I scrapped the motor and put on a new 2HP ($200.00.)   I made a belt-guard and because I had pair (no pun intended) replaced the cheesy little wheels with some larger ones.  I didn’t care for the air-filter so I made a Plenum and created a new filter with a substantially larger filter.The largest job I have asked of it was when I restored and repainted my Pilatus glider.  It has never let me down.  (The compressor nor the glider!)  When I had my shop wired, I had the electrician install 3X20A breakers.   If I need to use the compressor outside of the shop, I use a 50’ 10/3 cable I made and with a plug-adapter (20A to 15A)….. No “tripping”!  (Unless it’s me over the cord or air-hose!)  NOTE.  When I was getting ready to paint my glider, I bought a new regulator and oil-water separator.  An “inexpensive one”  !  The fucking regulator literally Blew-Up the first time I tested it (125PSI cut-off) and it grenaded pieces across the shop at well below the regulators rated Max PSI. Luckily I wasn’t near it or in the line-of-fire !   Lesson learned !  I took the pieces back to Princess Auto, got a refund but the next one I chose wasn’t in stock at that time.  A week later I returned to get the new regulator and noticed the one I had previously purchased had been removed from the shelves.  Probably because of a scathing letter I sent to Princess Autos head office !  There are some things you can’t “cheap-out” on !  All these years later my “hybrid” compressor is still going strong so in my case I saved about half the $$$$ and certainly have gotten the value and use.
Wouldn't be without a hose-reel !
 

Kawboy wrote:

.....On the way back she asks me " Why do you keep buying pieces of shit and have to fix them?

 

Is it possible we're married to the same woman?

Bucko wrote:

Kawboy wrote:

.....On the way back she asks me " Why do you keep buying pieces of shit and have to fix them?


 

Is it possible we're married to the same woman?

Not likely but I think maybe they all had Relationship Training 101 back in Grade 9 Home Economics . 

My two cents on this thread.

I have in the storage room where I keep tractors and other machinery an old compressor I bought over 20 years ago at an industrial machinery junk yard.

I took some pictures today.




His watch has long since stopped telling time.



It is equipped with a pressure relief valve that I have never needed to check.


It is oil lubricated and the accumulated dust protects it from corrosion.


The builder's plate shows its technical data and year of manufacture, 1972.
 

It has a 2.5 hp three-phase motor, it has never failed me to inflate the tires, use a pneumatic gun or blow air filters of the tractors.

It is old, without a correct maintenance and it works.

When it was built the term PROGRAMMED OBSOLESCENCE was not known.

That compressor is 52 years old and still chugging away. Are you sure it's not a Harley??