Two small air compressors or one large one?

I currently am using a 10 gal air compressor that can do 4scfm @90psi. It works well for about 3 minutes then just cant keep up and I’m brining through consumables. I know getting a 60gal compressor would solve that problem, but I’m thinking it might be a more cost effective option to get another smaller compressor and tether two together. If I were to have two 4scfm compressors tied together with a 20gal auxiliary tank would that work just as well as a big 60gal?

You would have just as much or more money into trying to join two compressor systems together as just buying a 60 gallon. I still see 60-gallon compressors on sale for $400.

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There is nothing wrong with running two smaller compressors…

Most plasma cutters I have seen want 6cfm, double that will get you the best performance for CNC.

With two small compressors putting out 4-5 cfm (8-10cfm total) you would be still on the low end of what you need.

Most compressors I have looked at mounted to a 60 gallon tank are putting out minimum 11-12 cfm which gets you into the sweet spot for what you need to ensure you have good clean cool dry air.

If it’s simply not in your budget I suppose you could try to program in a pause to allow your compressors to keep up.

If it was me I would save up for a larger one. Otherwise you will have spent a bunch of money and only marginally improved your situation.

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Good point… Didn’t think about that.

Where are you finding 60 gal compressors for $400?

menards,Blowes, HomeCrappo will have sales on them, have to watch.

Cheapest at Menards $700, cheapest at Home Depot $900, cheapest at Lowes $780, Cheapest at Harbor Freight $800. Even on sale these would still be a far cry away from $400.
I would love to get a 60 gal, believe me. But getting a second smaller 5scfm compressor for $200 seems a lot more doable.

Do you have a local trading post magazine??

Shop used sometimes you can find a good deals.

Even slaving two together I don’t think you will improve consumable life much if any.

Are you running any kind of dryer system with what you have?

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  • I am running a copper pipe separator (36" long, 6 pipes) that then leads into two desiccant dryers (5 lbs total). The longest I’ve ever been able to get my tips to last is about 10 minutes before they wear away or get covered in slag. Its cuts abazing for the first 3-5 min. *
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What are you cutting?

What settings are you using?

What plasma do you have?

It will be hard to remove all the moisture with that small of a compressor I am sure.

I know a guy that got a 60 gallon for 30 bucks was missing a motor. Motor was less than 200.

Cutting up to 1/4 steel and 3/16 aluminum. Everlast PowerPro 205si. 50amp 60psi.

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I assume you have bad pressure drops?

I would look into best air setup you can afford.

I would check on a used compressor.

May want to turn air up also not sure about that machine.

Catch them on sale, $400 3 weeks back , friend of mine got at Menard’s $419. out the door… Like I said watch for the sales.

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can you show a pic of your plumbing? Newer small compressors run at a very high rpm and run hot, this makes more water. A $400 compressor will be one that runs fast. Try to find a older used compressor they are out there just have to look. Most times I try to buy used quality used stuff then new cheap stuff. $400 for a compressor is very cheap in my opinion. I have a 7.5HP on a 80 gal tank and it was $3200 new 7-8 years ago. But the only thing I have for dry air is a refrigerated dryer and motor guard filters at point of use and I don’t even think I need those as I have had one for powder coat equipment that is over 2 years old and is as dry as the day it was installed.

Finding a used compressor on Craigslist or in the classifieds is very good advice from @Knick .I spend a lot of time on Kijiji, have a lot of saved searches that I check in every day and I’ve saved myself thousands of dollars on equipment.

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I do the same If there is something I want but dont need I save a search in C/L.
Some things I may wait a year or more before I find the deal I want. Then I will buy it and It may sit that long before I use it :rofl: :rofl:

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I’m hyper nostalgic and buy a lot of vintage cast iron sheet metal tools. I think I have enough cast iron on my property now to affect the rotation of the planet.

(Fun fact did you know the Three gorges dam in China holds so much water that it’s actually delays the rotation of the earth slightly.)

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That’s an interesting point, I hadn’t considered that a small compressor might have more water inclusion. I’ve been looking at compressors for a few weeks now both new and on Craigslist. It seems that in my area people are still asking $600+ for a 30 year old 60 gallon compressor. I’m still looking though.

Here is what my dryer setup currently looks like.

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Wow that’s impressive, nice job. Do you get much water out of it?
Are the two PVC set up for desiccant?

Not sure how much air you need or how much room, but it might be hard to find a small compressor that does not spin fast.
you will probably have to go with at least 5HP 2stage maybe 30 + years old. you want something that the pump spins around 700-900 RPM. Compare that to what you have, some of the small compressors pump’s run 3200RPM
Some of the shops you guys have are nicer then some peoples living rooms

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Thanks! Yah, the PVC is full of desiccant. I get some water out of it, but not too much. I live in a desert climate where it’s rare if the humidity is above 30%.