Shop Air Compressor Recommendations
 

In a bit of a quandary here…

I’ve been using a hand me down 5hp two stage DeVilbiss from my dad that HE bought as a surplus item from a service station in the late 50’s. This thing is probably close to 80 years old. Still works, but it is very slow to fill the tank. Probably doesn’t have any rings left in it. The 80 gallon vertical tank also scares the hell out of me since I can’t see the inside for rust.

I also have a much newer twin cylinder 10 HP Speedaire with no motor and a broken crank. Aside from the broken crank (shipping accident), it’s practically new. Seems like crankshafts are reasonable (if available).

I have always relied on air compressors for my work in the shop. Needs to be able to run a sand blast cabinet, plasma cutter, paint gun or air tools all day long at times. Trying to weigh the benefits of rebuilding the DeVilbiss, repairing the Speedaire, or go with something new.

If I go new I want quiet, powerful and durable. Any of you hard core shop guys have any thoughts?

Eastwood just came out with a quiet one. It ain't cheap but very quiet.

https://www.eastwood.com/eastwood-el...echnology.html

I really dislike listening to an compressor run, my answer was to build a shed outside for the compressor, gets rid of the noise, and likely a tank rupture will harm no one. it also frees up floor space in the garage. I made the drain for the tank to reach inside the garage for ease of draining.

Over the years I ended up 2, fairly new units with 5 HP single stage compressors. I'm going the plumb them together to give me 100 gallons capacity, and 2 compressors in their own shed.

The tanks on the old compressors were much stouter than newer stuff. My father had a 1940s Par compressor that sat half full of water for years and to my knowledge is still around. It weighed a ton if you had to move it.

HF sells a compressor head for likely less than you can buy a crankshaft:

https://www.harborfreight.com/5-hp-1...ump-59672.html

Good luck in whatever avenue you choose....;)

Unlike Sirrotica, I love listening to my compressor pumping air...7.5HP single phase with V4 pumping. It's like the 455 of air compressors :).

After having a 5HP 2 cylinder and then the current one, I would not go any smaller...I can sandblast with a pressure pot or use my sandblasting cabinet as long as I want and never wait for air.

If the tank on the bigger unit is OK, I would price out a replacement crank and motor vs. buying a new unit. Unfortunately, you may find that the parts are more than a complete unit.

Personally, I’m a cheap azz, and think 98% of new stuff is garbage.
I’d look into rebuilding that DeVilbiss in a heartbeat. It’s not hard to rebuild a compressor.

It sounds like you are used to using quality equipment. This means spending several thousand dollars minimum to end up happy. I used a 5 HP single stage Campbell Hausfeld 60 gallon vertical compressor for about 20 years. Then I thought I lucked into a Dayton, 2-stage 6 HP 80 gallon vertical compressor. It has full pressure lube and a spin on oil filter. Well, the motor was shot. So I had it repaired. Then It wouldn't create any pressure. Ended up having to buy a new cylinder head package because they don't service the reed valves anymore. Long story slightly shorter, I spent $750.00 on parts to fix it up like new. At first I was pretty pissed at all the hassle and expense. 6 years later, it was a good investment. It is quiet, makes 175 PSI if needed, will likely outlive me. I would fix the one with the crankshaft issue if parts are available. Everything new unless you get into an industrial grade unit is low grade junk that may last 5 years in daily use if your lucky.

I’m sensitive to economics but I’m not afraid of paying money in return for a good value.

The crankshaft for my Speedaire 3W493 is turning into a bit of a struggle to find.

My first move would be to do the legwork to really find out what it would cost to put either of the high quality compressors into reliable, safe condition.

Then compare that cost to what you can get for that same amount of money in a new compressor.

If it ended up being .. say $2000 to get either one of the quality compressors into a condition that would work reliably for 20 years, then that would be the route that I personally would go in a heartbeat.

I used a 1930s vintage compressor for a while, still had the original motor ... wife made me get rid of it when I left the power on and it tried to cycle on at night with a failed unloader valve, smoked the motor and filled the house with smoke.

Lowest noise and best performance, probably Eaton Compressor. You can stand next to it while its running and carry on a conversation at your normal speaking voice.

I have an odd hobby of making workable air compressors out of peoples cast off old ones. There are obviously three main components as you know: The tank, the motor, and the pump. Tanks aren't hard to find, and neither are serviceable motors. Most times, I have been *given* the tanks and motors for free, and the only investment is pump and possibly some fittings or copper tube.

Here's the crazy thing. I have had really good success with the HF compressor pumps. One of them is going on 7-8 years now. I do THREE no-load break ins, with oil changes afterward.

I've attached the most recent one.

For 12 years I've been using an Eaton every day. This is the current version of it. I have zero complaints about it.

https://eatoncompressor.com/product/...llon-vertical/

Those air compressors are produced about 10-12 miles from where I live. They are absolutely the exception to the rule of new equipment being disposable junk. If I was a young man again and wanted a "lifetime" air compressor, that's the one I would buy.

Anyone have a good source of parts for obsolete compressor parts? It seems like I waited too long to grab a crank for my Speedaire 3Z493. What was once a standard catalog item now feels like trying to locate NOS RAIV heads.

Also interesting comments about the big HF compressors. I’m a “quality first” guy for tools like this, but I can’t believe the prices of some of this Chinese stuff.

Nothing intelligent to add as I use a big cobalt job I got for half price from lowes. It was around $200 and has been doing a great job for 7 or 8 years now. But, my question about a rusty tank failure that some say they are afraid of. I doubt there will be any 'explosion' or catastrophe in the event of a failure. I had an old sears job 40 years ago. The tank must have been made of very thin gauge steel. It didnt last too long but when it rusted through it was just a matter of a hole in the tank and no pressure. IF its not holding air how will it be pressurized enough to blow? Just a thought.

I had a tank rust through, and it just started leaking finally. I don’t really understand how one could catastrophically “blow”, but I’m no scientist.

I have personally seen firsthand the aftermath of a compressor tank explosion. Granted, it was a 20-ish? gallon horizontal job, with wheels for mobility. Very commonly available. The tank seam was on the bottom, closest to the floor, where the condensation accumulates. .It belonged to some friends of ours. The destruction was immensely worse that I would have expected. It opened up from the bottom along the seam. This massive pressure causes a handful of things. This propelled it with some sort of triagonal trajectory, leaving marks in both the wall and the ceiling. The 16' garage door was destroyed from the blast, and it also broke the door to the house as well as the parts of the doorjamb. Shrapnel from the tank messed up the sides of two vehicles, necessitating both having their entire sides repaired and repainted. I don't know what the total was for all of the damage, but it had to have been quite substantial. Why it didnt just leak out is a very good question, and I do not have the answer. Maybe just some anomaly in manufacturing? No idea. Until I saw this, I didn't even consider it a possibility that it could do this much damage.

It has made me consider some sort of anchoring mechanism for the two different 60 gallon compressors I have.

Good to know, I had just have it turn out differently in my case.

~125psi caused all that damage? Wow! Glad no one was hurt.

That does sound like a mess. I suppose if a welded seam failed at once it could happen. May have been a one in a million chance as well? I do have both of my large stand up compressors bolted to the floor and both are housed inside a 'closet'.

My Ingersoll Rand from Tractor Supply just hit its 20 years. Had to replace the switch once and oil changes. That's it.

I have a Craftsman from ‘88. The original 35 gallon tank rusted out. I bought a 60 gallon off of a local radio buy/sell/trade show. Then pulled the motor off and took it to a local electrical shop to have them go through. I then tore the pump down and flipped the reed valves over and made gaskets out of gasket material, as none were available anymore. Total cost I remember to be around $110 for the whole project.
Nice to live rural BTW, we still have guys locally who rebuild starters, alternators, generators, and motors, as farmers rebuild stuff instead of replacing! :)

Bought a Quincy compressor 5 years ago now. Been a great one, and quite. Used to run big Quincy's in car dealers. They were very reliable. The Quincy's in one dealer ran about 40 years.

A Quincy was my second choice. I spent a couple of months researching before I made my decision.

I bought a BelAire probably 10 years ago. Better specs then husky/lowes stuff and was neither the cheapest or $$. I'm happy with it, but was chagrined to find out that the harbor freight compressor I'd skipped over had exactly the same compressor pump as my belaire. Just cheaper electric motor installed. At that time both my pump and the harbor freight pumps were made in Italy.

With electric impacts now, this unit is the quietest, and takes up less room, it's nice. 60 gallon equivalent.
http://forums.maxperformanceinc.com/...6&d=1736058558

I second that option as the noise from a running compressor, no matter the size, gets on your nerves. I built a small shed with one side devoted to our garbage (that, I also hate seeing inside a garage) and the other side with sound insulation for the compressor. It has an automatic drain and everything is plumbed underground to the garage.

You can hardly hear it when sitting on the deck outside.

I didn't want the compressor and drier outside, so I built this room around it. Both are plumbed to bleed off moisture through the exterior wall.

Those scroll compressor are vastly superior to conventional models. I think painters have kept away from them because of the oil in the air that needs lots of separation to remove.

Now they have "oil less" scroll compressors that evidently use teflon or something to seal the scrolls instead of oil.

I think the vast majority of big commercial compressors are the scroll type.

Also known as "screw" compressors, one advantage is instant working pressure. No need to wait for a system to build pressure. Plus they are quieter than conventional piston compressors. When I was comparing, the screw type was about double the cost of piston driven pumps.
Repair cost is much higher on screw compressors.

Finally, an informative air compressor thread. I'll be ordering this one soon:

https://eatoncompressor.com/product/...l/#description

My 25-yr-old oil-free Craftsman 2hp compressor finally bit it. It was never quite enough to run tools continuously but was close enough for me to get a lot done for not much money and a small footprint.

I needed it to run my mini belt sander and right-angle die grinder so decided to buy a little larger one for as little money as I could get away with. I could not find anything close to the same performance as my old 2hp in a 120V oil-free so rolled over and bought a budget DeWalt (MAT) on sale at Tractor Supply.

I got it home and a couple days later ripped up my hamstring pretty bad. Being hobbled, I used the downtime to learn more about Fusion/CAD by laying out a small cooling coil with hopes of it actually doing something to lose some water.

Here's what I ended up with:

https://forums.maxperformanceinc.com...1&d=1776312212

It took an electrician and the equivalent of a 2nd mortgage to buy brass fittings (when did this happen?) but finally got it up and running today. I choked on the cost of copper tubing and went with aluminum.

I ran the 30-minute break-in but have yet to pressurize the system past about 30 psi. I am going to go slow until I have confidence in my plumbing but so far, it's working and it makes a LOT of noise. I will be doing what I can to quiet it down...Solberg silencer going on tomorrow...

https://forums.maxperformanceinc.com...1&d=1776312614

https://forums.maxperformanceinc.com...1&d=1776312631

Mike

Get a screw-type and never look back. If you run a business off of it, it's worth the investment.

Similar setup to mine, except I set mine up to dry the air before it goes in the tank, then it gets a bit more drying after it leaves the tank. I used a big oil cooler as an "after cooler" with a fan that comes on when the compressor runs, it's immediately after the air leaves the compressor cylinders, and two separators before the air goes in the tank.

Yours will definitely make air dry enough for air tools, the separators work pretty well.

Know absolutely NOTHING about what is currently available new.

My input to the thread is that rather than one huge compressor, I use TWO in parallel.

I have two 8 HP Craftsman with 60 gallon tanks.

Adjusted the auto shutoff to 150 psi. Periodically change which compressor kicks out first.

Both compressors AND the vacuum unit for the beading machine are in a different room of the shop, with no connecting door (outside door only). Really cuts down on both the noise and the dust!

These are probably 35 years old; have never had a compressor failure (well, a Monkey Wards diaphragm type for a paint gun from the 1940's had a diaphragm failure some 60 years ago).

Have had a couple of tanks rust holes in the bottom (vertical tanks), which I repaired with an outside plate and sheet metal screws. The vertical tanks with round bottoms tend to have moisture congregate in a small area, most goes out the drain. Would never use a horizontal tank with high pressure.

Jon

I did see a lot of videos on YouTube describing transmission coolers for chillers.

I didn't want to go that far on a cheap compressor without a real need. Our air starts pretty dry and I rarely had condensate at a tool, but it did happen. I would rarely see condensate at the bottom of the tank on my old one. I just did "something", hoping for better than nothing.... maybe a waste but it's what I did. I don't need a compressor enough for me to justify a serious effort.

The noise in my garage WILL be an issue. I replaced the basic intake filter with a Solberg intake silencer/filter. It knocked the noise down a little (~2.5 db per an uncalibrated app) but definitely reduced harshness. I'm happy with that decision.

I may try some dynamat or similar on the tank. Anyone have experience with this? I can also put some acoustic foam on the adjacent wall... maybe buy some engineered acoustic spacers for the pump mount (it already has some elastomer mounts)?? The tank just seems like a big resonator with a lot of surface area.

Never thought about damping the tank vibration, yeah, you'd think it would ring like a bell. Good idea.

The "after cooler" I put on quieted mine down quite a bit, it softened the "hit" on each stroke, I guess it's because the hot air immediately shrinks when it enters the cooler and lowers the pressure right at the cylinder output. But mine is a two stage 175 psi, so the air is very hot coming out of the second stage.

Isn't condensation a problem in the winter?

Your compressor is clearly about 20 notches higher on the quality scale so is probably quieter to begin with. Mine is the basic "entry level" 220V, 3.7 hp box store version that is sold under many brand names. All made by MAT.

Yes, the noise is worse than I expected but is what it is. Interesting to hear your after-cooler reduced the noise. Your hypothesis makes some sense but it may just have more to do with compressible volume between the pump head and the check valve? dunno but glad it helped.

I bought some pads to put under the feet but can still feel shocks in the concrete slab. I am going to change the pads to neoprene foam and see if that helps.

I also put an aluminum heater pan under the compressor, thinking it would help contain messes from condensate draining and maybe oil. But I now think this was a bad idea for noise and will try getting rid of it. Basically, I suspect it is a big metal drum head getting whacked and radiating noise.

I am curious to know if anyone has put acoustic foam against an adjacent wall and if so, did it help?

As to damping the tank, I don't have a plan yet but makes sense to me. Something like dynamat...

I second the Ingersol Rand compressor. I have the 80 gallon 5hp 2 stage 175ps in a little room inside my shop. When I built the shop in 1999 I plumbed the walls with heavy duty 3/4" PVC piping. I run no more than 90psi through it. It has held up well for 27 years.
If I need more pressure I disconnect the in wall piping and hook pressure rated hoses the the manifold on the outlet side of the pump' I can regulate the pressure at the manifold for what ever I need.

Interesting to hear your after-cooler reduced the noise. Your hypothesis makes some sense but it may just have more to do with compressible volume between the pump head and the check valve?

That's exactly what it is, between the added volume, and the shrinking air, between compressor head and check valve, I'd imagine there is way less "shock" in the system.

Kinda like a silencer on a firearm.

I get this. I want to reduce the tank cut-out pressure to reduce stress on the plumbing and the compressor. It has a Condor pressure switch. I'm not sure what the range of adjustability is. I don't need nor want more than 60 or 70 regulated psi for the few tools I use. I actually think 100 to 120 psi cutout would be fine.

I have a call into Condor to get guidance on adjust vs replace with a lower-range pressure switch.

I added a 1/4" valve to bleed the tank yesterday. I found an adjustable-flow sintered muffler and ordered it so I can just open the valve to a kinder gentler experience than a sonic boom.

Pressure switch company (Condor) tech support was awesome.

The cut-out is all mechanical and the range of adjustment on mine is huge.

I had no trouble reducing from 155 psi to 100. I flipped the breaker off when the tank hit 100 and turned the cut-off adjustment screw until it tripped. My pump will be happier, my plumbing will see less stress, and if I discover a downside, a turn of a screw will fix it.

Replaced stiff pads with low-durometer foam pads, hoping to reduce noise and vibe transmitted into my garage floor. Jury is out.

The pics also show the silencer I installed- definite noise reduction... along with the sintered muffler to bleed off pressure from the tank. Much better than the loud blast without it.

https://forums.maxperformanceinc.com...1&d=1776723302

I also hung a wooden bracket off the compressor and ordered a hook so I have a place to hang my hose. The only things left are a drain valve extension that will encourage me to use it and an hour meter to remind me about maintenance.

No more excuses to avoid body work... darn...

https://forums.maxperformanceinc.com...1&d=1776723689

Tractor supply has the Ingersol-Rand 5hp 2 stage 80 gallon compressor on sale for $1199.00

I haven't had any moisture issues in the winter. In addition to the timed mechanical drain, I installed an inline auto drain directly on the outlet to the underground 3/4" line to the garage. Also, using synthetic oil like many others here.