Your thoughts on a replacement compressor

Topics include, Machine Tools & Tooling, Precision Measuring, Materials and their Properties, Electrical discussions related to machine tools, setups, fixtures and jigs and other general discussion related to amateur machining.

Moderators: GlennW, Harold_V

Post Reply
User avatar
NP317
Posts: 4557
Joined: Tue Jun 24, 2014 2:57 pm
Location: Northern Oregon, USA

Re: Your thoughts on a replacement compressor

Post by NP317 »

Greg_Lewis wrote: Fri Feb 19, 2021 12:37 pm They also said that consumer-grade piston machines are not designed for continuous operation (which I have sadly discovered).
Greg_L:
That fact of duty cycle is part of the reason I am looking at the PUMA PK6560V air compressor mentioned above.
It's CFM output is high enough that my usage would cause the compressor to cycle, rather than run full on, like my smaller one tends to do now.
The next step up would be a 2-stage unit that can maintain 100% duty cycle. And even more buck$$. And outputs far beyond my requirements.

Interestingly, I cannot find a PUMA dealer in the Portland, OR area. The only reasonable online sales I can locate so far is
https://www.aircompressorsdirect.com
And they offer free shipping (included in their price) with lift gate delivery direct from the PUMA factory, which I require.
So I am finding limits with sales.

Home Despot sells some models of PUMA compressors but not the one I want. Like Tractor Supply they probably sell special units from PUMA.
'Wish this was an easier process. But certainly worth the research effort. I am glad I don't require a replacement compressor TODAY!
RussN
Inspector
Posts: 721
Joined: Mon Feb 23, 2009 4:25 am
Location: Saskatoon, SK, Canada

Re: Your thoughts on a replacement compressor

Post by Inspector »

With respect to motor horse power. My compressor has a 5HP Marathon motor (US made) and draws 29 amps according to the data plate, so real horse power.

I understand some of the oil changes and all but when did car makers decide that brake fluid has to be changed every 16,000 kilometres (9,950 miles)?

Liveaboard my Mahindra tractor is just a little 26hp thing and the rear end/hydraulics takes 37.5 litres/10gallons so I feel your pain. Finding a place to take used oil is the tricky part.

Pete
User avatar
liveaboard
Posts: 1971
Joined: Sun Dec 08, 2013 1:40 pm
Location: southern Portugal
Contact:

Re: Your thoughts on a replacement compressor

Post by liveaboard »

I store up old oil in a 5 gallon container and then take it to my local tractor shop; he has a big storage tank and gets paid a little for the used oil.
In Netherlands I had to take it to special government waste center.
Ask at local garage or whatever what the situation is where you live.

Brake fluid gets contaminated after a while and destroys expensive things. But it does last a long time.
I change mine once every 5 or 10 years (but my cars stay inside and we have mild weather).
Or when I get a "new" car.
I changed the differential oil in my 22 year old Mercedes, it was thick like honey. Manual gear oil too.

I use gravity for brake fluid change or bleeding. It's a bit slow but requires no second person to help, or special tools.
And don't forget the clutch fluid!
User avatar
Bill Shields
Posts: 10463
Joined: Fri Dec 21, 2007 4:57 am
Location: 39.367, -75.765
Contact:

Re: Your thoughts on a replacement compressor

Post by Bill Shields »

Brake fluid is very hygroscopic ..absorbs water..water migrates from master cylinder down to wheel cylinders where it causes pitting around where the seals sit unattended in parked cars.

There is some logic to these commendations..especially it DOT 4 fluid (I may have my DOTS confused). Back in the 1970's when disc brakes became popular it was a legit problem if you did not flush the fluid periodically.

Them along came DOT 5...
Too many things going on to bother listing them.
User avatar
warmstrong1955
Posts: 3568
Joined: Thu Mar 18, 2010 2:05 pm
Location: Northern Nevada

Re: Your thoughts on a replacement compressor

Post by warmstrong1955 »

Bill Shields wrote: Fri Feb 19, 2021 8:19 pm Brake fluid is very hygroscopic ..absorbs water..water migrates from master cylinder down to wheel cylinders where it causes pitting around where the seals sit unattended in parked cars.

There is some logic to these commendations..especially it DOT 4 fluid (I may have my DOTS confused). Back in the 1970's when disc brakes became popular it was a legit problem if you did not flush the fluid periodically.

Them along came DOT 5...
That's why brake systems that use it are closed systems. If working properly, the only air (with humidity) that is in the system is what is in the top of the master cylinder reservoir when you install the lid.
Today's solutions are tomorrow's problems.
User avatar
NP317
Posts: 4557
Joined: Tue Jun 24, 2014 2:57 pm
Location: Northern Oregon, USA

Re: Your thoughts on a replacement compressor

Post by NP317 »

DOT 5 fluid is silicon, and therefore not hygroscopic. A nice improvement.
I have replaced my share of rested brake cylinders.
RussN
User avatar
Greg_Lewis
Posts: 3014
Joined: Wed Jan 15, 2003 2:44 pm
Location: Fresno, CA

Re: Your thoughts on a replacement compressor

Post by Greg_Lewis »

Getting back on topic, I have made a decision! Ta da!

Warmstrong’s suggestion of a two-stage compressor remains a good one for those whose use is heavy. In my case, the use is light and as I wrote above doesn’t warrant the cost not only of the compressor but the related upgrade to the electrical and air distribution systems. The single-stage machine I had lasted 34 years before the popped air hose killed it.

So the decision has been made to order the 5-hp three-cylinder pump from Eaton and put it onto the existing tank with motor. Said tank and motor are already wired and piped. The pump is this one if you should want a look: https://eatoncompressor.com/product/5hp ... mp-18-cfm/

So here is a review of what I’ve learned:

The Ingersoll Rand SS4L5 sold by Tractor Supply has a pump made either in China or India. There are a few negative comments about customer service and warranty claims.

The Quincy is also made in China, and there are also a few negative comments about service and claims.

(Something else I noted was a review which said they had an early head gasket failure on a Chinese pump and discovered the head bolts were not torqued down evenly and some were almost loose. So I’ll be checking all the fasteners on the new pump.)

I called both Puma and Eaton. The Puma rep. said the pumps I’d want were made in Taiwan but they don’t have any in stock and no idea when they would. He said the factory was in turmoil because of the virus and the weather and they have no idea when they will be back to work. He also said they have containers on the dock in Taiwan they can’t get because of the virus and the political unrest there. There are many backorders that have to be filled first. (He also said they make compressors for I-R.)

I called Eaton and spoke to a rep. who answered all my questions without hesitation. They have the pump in stock and she said it was made “near Singapore,” which means Malaysia, to their design and specifications. Their website says the warranty is five years which she confirmed. No one else has a warranty close to that. You do have to buy the maintenance package of oil and filters but it’s only $40, compared to $90 for the I-R with two quarts of oil and two filters for a two-year warranty.

She also said that this warranty is for parts — you do your own work, which does not void the warranty. I like that idea. I’m often more picky than someone on the clock who’s thinking about leaving early for the weekend. And finally, the pump ships UPS while I’ve heard that some of the others ship by truck. She said the shipping would probably be between $70 and $90 from Ohio to California.

After all this and knowing what I know now, if I was starting from scratch like RussN, I think I’d do one of two things: Either buy the complete unit from Eaton (even though it would require an electrical upgrade) or take the Dinosaur’s suggestion and build one using an Eaton pump, this tank
https://www.compressorworld.com/60-gall ... 10044.html
and a motor sourced from Craigslist. The components could be sized to fit the available electrical supply (Eaton lists a 3 h.p. pump and such a motor would only draw 11 amps.).

The cost of the pump and tank would probably be about the same as a complete Chinese compressor but I’d have the better pump warranty, which is where most of the failures reported on the net seem to be.

So I’ll be ordering the Eaton on Monday.

Thanks everyone for all your thoughtful input. I’ll come back to this when the pump arrives and is installed and let you know how it went.
Greg Lewis, Prop.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 35 years of turning perfectly good metal into bits of useless scrap.
User avatar
NP317
Posts: 4557
Joined: Tue Jun 24, 2014 2:57 pm
Location: Northern Oregon, USA

Re: Your thoughts on a replacement compressor

Post by NP317 »

Greg:
Thanks for your report. All very interesting to me.
The pump you have chosen is similar to the pump on the PUMA compressor I am looking at:
3 cylinder single stage, but yours will have the pressure relief circuit to allow continuous running. Its looks like a good unit.

Building up my own compressor is not an option, due to the age of the air tank. Not going there, as that is my main concern.
I should be able to do UT testing on the tank by mid-week.
I will also share my decision when it is made.
RussN
User avatar
BadDog
Posts: 5131
Joined: Wed May 17, 2006 8:21 pm
Location: Phoenix, AZ

Re: Your thoughts on a replacement compressor

Post by BadDog »

I finally talked to my buddy. I thought I remembered him having some specific problem(s), but he didn't have much to say except a general disappointment with what he got relative to what they claimed. He says it's still working just fine now some years later, but he gives it only a few marks above a HF unit. The best he could say about it was (to paraphrase), he felt he got fair value for what he paid, which isn't a terrible rating from him.
Russ
Master Floor Sweeper
User avatar
Greg_Lewis
Posts: 3014
Joined: Wed Jan 15, 2003 2:44 pm
Location: Fresno, CA

Re: Your thoughts on a replacement compressor

Post by Greg_Lewis »

Thanks for the follow-up BadDog Russ. Considering that any pump in this price range is not going to be a class AA item, like your friend as long as I get what I paid for, I'll be happy. At $300, if I get $300 worth of use out of it, I'm OK. If it lasts through the five year warranty, that's $60 per year. Tolerable.

(BTW, there are many good reviews of the HF pump, but also a significant number of bad ones. The issue there may be quality control.)
Greg Lewis, Prop.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 35 years of turning perfectly good metal into bits of useless scrap.
User avatar
NP317
Posts: 4557
Joined: Tue Jun 24, 2014 2:57 pm
Location: Northern Oregon, USA

Re: Your thoughts on a replacement compressor

Post by NP317 »

Follow-up:
I purchased a new air compressor from PUMA, and received it one month later. They assembled it in the Memphis, TN, factory from parts in stock.
It is now partially installed in my shop, waiting for me to acquire the last correct cables and plumbing.

I got the PUMA Air Compressor model PK-6560.
This pump is a 3-cylinder single stage pump, 240 Vac single phase, 5 HP unit. It is well built with an ASME-approved 60-gallon tank, with excellent machine welds. The cast iron pump is beefy, with easy to access anything requiring servicing.
I can power it from my existing 30 Amp circuit, needing only to change the outlet socket to the correct NEMA 30 Amp. That's is already done.

Before installation I have made some improvements: Plumbed the tank-bottom drain valve out through the included pipe support at the bottom front. Now I can drain the tank with my foot operating the valve. I also added fittings to the tank air pressure gauge, rotating it so it reads vertically instead of being on its side. And I added a pressure regulator+dryer to the tank main output. Even mounted it in existing holes in the pump bridge frame. Thoughtful thing for PUMA to include those holes. And finally I drilled holes in the concrete floor for threaded inserts, and placed the three legs on rubber pads before securing them to the floor.
This compressor will more than meet my needs.

My 40(?)-year-old Sears air compressor is 2 HP, 20-gallon, single stage unit, and one of my sons wants it. I did perform UT thickness testing on the tank, and cannot find any thin sections. Because this pump is oil lubricated, the small amount of oil that ends up in the tank probably prevented rusting inside. I compared upper tank thickness with bottom measurements. Differences of less than 0.005" (!) So it should be safe for the limited use it will get.

I am very satisfied with the new PUMA air compressor. I was able to get every specific design and performance element I wanted.
Now to power it up soon...
RussN
Attachments
IMG_3868.JPG
User avatar
liveaboard
Posts: 1971
Joined: Sun Dec 08, 2013 1:40 pm
Location: southern Portugal
Contact:

Re: Your thoughts on a replacement compressor

Post by liveaboard »

Congratulations on your new compressor; I wish you a good and durable relationship.
Post Reply