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My air compressor is probably over 50 years old, so when I found the bottom of the tank rotted through, I wasn't too surprised. It's a big unit with an 80 gallon tank. Besides air tools, I also have a small blast cabinet and a canister sandblaster. Do I need such a big compressor?

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Bigger is always better when it comes to air compressors. If you've had a big one, you will not be satisfied with a smaller one, especially running a blast cabinet and sandblaster.

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52 minutes ago, Steve Braverman said:

Do I need such a big compressor?

Yes.

 

40 minutes ago, Matt Harwood said:

Bigger is always better when it comes to air compressors. If you've had a big one, you will not be satisfied with a smaller one, especially running a blast cabinet and sandblaster.

 

This^^. "I wish I had bought the compressor one size smaller" said no one, ever.

 

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I agree with Matt and Bloo.  Had an 80 gal  6 1/2 hp 2 stage air compressor but sold it with the house when I moved from NJ to PA.  Thought I could get away with a smaller 60 gal 3 hp unit.  Wrong.  Saving up for another 80 gal 2 stage.

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First, the size of the tank or HP rating are not important or intelligent considerations when looking to buy or upgrade an air compressor.

They’re merely marketing gimmicks to hoodwink consumers, just like with many other consumer products, including cars.

How many new car buyers are enamored by and excitedly recite (higher ?) HP numbers of their vehicle, without even understanding what, if anything, it actually does or means for them in practice.

 

Second, OP indicates the “tank rotted trough”, but makes no mention of condition or size of the air compressor itself or the motor, which, especially the pump, are more important part of the entire equation than the tank.

If these “over 50 years old” components are in reasonably good condition and serviceable, depending on their brand and construction, their overall quality might be far better than anything new (Chinisium crap) one can buy for less than $3000-$4000, so another option is to service the pump + the motor and just replace the tank (& remember to drain it more frequently to prevent rotting).

Edited by TTR (see edit history)
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P.S. To determine whether an air compressor is adequate for expected performance, let's say using it for a media blasting or power tools, look for its output, i.e. CFM rating (not “GPM” rating, as I initially posted under significant influence of adult beverages).

 

Depending on type of equipment, materials and operating pressure (60-90+ psi ?), media blasting usually requires at least 15+ CFM compressor output, but to play it safe,  I would recommend 17+ CFM, as most hobbyist will likely not need much more. Most air tools use about 12-15 CFM (@90 psi).

 

One can have the largest tank in the world, but if the air pump (= compressor) cannot keep up, maintain or surpass extended usage, the tank (= reservoir) pressure will eventually become low or even empty during use and then, depending on the air pumps output, it might take a long time refill it back to useful pressure again.

 

 

Edited by TTR (see edit history)
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10 hours ago, Ben Bruce aka First Born said:

I thought it is CFM.

 

  Ben

You’re absolutely right Ben. 👍

Too much Tequila, Whiskey and Wine, not to mention a great Cigar …

… and couple of Wheat Beers tonight for this old cowboy ?

 

Fixed now.

Edited by TTR (see edit history)
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Posted (edited)
On 6/11/2022 at 12:50 AM, TTR said:

 

Second, OP indicates the “tank rotted trough”, but makes no mention of condition or size of the air compressor itself or the motor, which, especially the pump, are more important part of the entire equation than the tank.

 

If these “over 50 years old” components are in reasonably good condition and serviceable, depending on their brand and construction, their overall quality might be far better than anything new (Chinisium crap) one can buy for less than $3000-$4000, so another option is to service the pump + the motor and just replace the tank (& remember to drain it more frequently to prevent rotting).

I think the motor and pump are fine. I've looked into a new replacement tank, and the cost is about the same as a new compressor. Even though I think they're fine, a new compressor will probably be much better, even if it is chinesium. 

 

Tractor Supply has the same size compressor, and it just went on sale. I think I'll pick it up, and hopefully it will outlive me. I will be sure to drain the tank more often!

 

https://www.tractorsupply.com/tsc/product/ingersoll-rand-80-gallon-5-hp-reciprocating-air-compressor?cm_vc=-10011

Edited by Steve Braverman (see edit history)
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Looks like a fairly reasonable package for home/hobbyist use (+ IR has some experience building compressors and at least claim this one being US made 👍). 

Only other thing I would check (since there’s no mention of it) is the RPM it’s designed/intended to run at, i.e. +/-1750 or +/-3450. 
For variety of reasons, slower RPM would be preferable.

I’ve been thinking of getting one for our garage at home and might look into one of these.

 

Edited by TTR (see edit history)
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I went to TSC to look at the Ingersoll Rand compressors. They have a huge decal on them the says, "Made in USA," and in smaller type, "from global components." The pump is made in India. My old compressor is a Saylor-Beall. I looked it up, and it's a $3-4k unit new. Now I'm undecided between buying a new tank and restoring my old compressor, or just buying the new one. In all fairness, the new IR will probably last me forever.

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23 hours ago, Steve Braverman said:

I went to TSC to look at the Ingersoll Rand compressors. They have a huge decal on them the says, "Made in USA," and in smaller type, "from global components." The pump is made in India. My old compressor is a Saylor-Beall. I looked it up, and it's a $3-4k unit new. Now I'm undecided between buying a new tank and restoring my old compressor, or just buying the new one. In all fairness, the new IR will probably last me forever.

Thank you Mr. B., for taking time with the follow up on this topic, including discovery and revealing some sad realities related to manufacturing/marketing claims and the pause(?) they gave you.  

Seems like you're on the path to informed/intelligent decision making. Good luck with whichever you reach. 👍

 

 

P.S. As a side note, my first compressor which I bought from an estate sale of a friends FIL over 30 years ago was a used, probably 40-50(?) y.o. (at the time) smaller 2-stage (originally 15-17 CFM ?) IR that looked like it had always been stored outdoors and if I recall correctly, in fact behind my friends FILs a small body shop.

I also bought a tool box full of old body work tool + other equipment, all for full, but reasonable asking price (IIRC, compressor was "valued" by the estate at around $300.-). 

 

Anyway, I hauled the compressor (along with everything else) to my newly established (restoration) shop, cleaned + fully serviced it (& made a few small upgrades) and put it to work, which it did well for following 20+ years, until less than 10 years ago, I unexpectedly saw a year old (=like new), bigger/stronger, 2-stage IR (24 CFM) combo displayed for sale in front of some shop that was closing 1/2-mile down the street from me. They were asking $1400.-, I offered $1000.- (in cash) which they promptly accepted (later research and paperwork they gave me revealed a price of new one was around $4500.-). 

After basic service of the new one and switching it to use, I rolled the old one to the curb with a "For Sale" sign (incl. $750.- price) on it and sold it couple of hours later to someone driving by. He offered and paid $650.- after we rolled it back to my shop and plugged it in for proof of its working condition. 

 

I don't really expect having to buy another one for the shop for the rest of my life, but have been on the lookout for one to put in (or behind) the garage at home, especially now after my wife retired and I turned part of it into her arts/crafts/gardening shop (she just hosted a miniature mosaics/tiling craft party last Saturday and all her friends were allegedly envious of the work space I had recently created and equipped for her).

Edited by TTR (see edit history)
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On 6/17/2022 at 4:00 AM, ILIKECARS53 said:

Tractor Supply IR compressors ........   Please read the reviews.  There are many complaints about the motors.

Good point, since the overall quality of any equipment is the sum of the quality of its components/parts.

 

OTOH, I rarely read product reviews of anything due to knowing reviewers qualifications.
I prefer to use my own critical thinking coupled with common sense and logic instead.

 

To use air compressors for example: A good quality 2-stage air pump delivering sufficient amount of air commonly needed for automotive restoration related equipment, tools and work will probably costs $1000.- to $2000.-at minimum, a quality electric motor probably at least +/-$1000.- and a well built (& safe) tank at least $+/- $1000.-.

 

So, if using above (estimated) figures, how good can a less than $2000.- compressor combo really be, let alone one for less than $1000.- ?

 

YMMV.

Edited by TTR (see edit history)
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  • 2 weeks later...

 An air compressor should be rated for the amount of air (CFM @ pressure that you need) Not the size of the air tank.

 

If your compressor does not supply that amount of air, you will need a larger tank in order to store enough air to use it for a short amount of time. Then you will have to wait until the tank fills up again.

 

 The better air compressors run at lower RPM's not 3400rpm's.

 

 Ps, I have a new 30 hp screw compressor, But, I still keep my 75 year old 20 hp compressor as a back up. Still works fine.

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Make sure whatever you buy the motor is a 1750 RPM not 3450.  Air compressor companies Gin up the ratings of 3450 motors to try to make there HP higher for advertising and they don't hold up.  The Ingersoll Rand brand make some good industrial compressors but they also license their name to others who make really cheap compressors that don't last.  I recommend Champion as being a good value with a 1750 RPM motor and an 80 gallon tank most hobby shops would be fine with a 5 HP.

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  • 2 weeks later...

I bought the IR compressor from Tractor Supply, and so far i'm happy with it. I know it's not of the same quality as the unit it replaced, but it's new, it's quieter, and it doesn't leak. For those that asked, it runs at 1750 rpm.

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