Advice or input on compressors
 

I have been following the beginner paint thread and it got me thinking. I have an old Craftsman compressor that was my grandfathers. Every time I put an extension cord on it, the breaker pops in the unit or at the panel. Last time is shut off and started smoking, so I think it is about done. LOL. It is a very old machine and I am going to get something a bit more modern. I use it mostly to fill up tires and little stuff, but with my son's 69 in the mix now, I would like to start learning how to paint and run some impact tools with it. I would like it to be portable or movable, I don't have a lot of room in the garage right now. But that is not set in stone, as I will be putting up a small shop and storage shed in the backyard to move all my crap out of the garage. Budget is always an issue, so I cannot go drop big money on a pro style machine.

So, what I am looking for is input from the group on if a 30 gallon compressor like the ones at Lowes or Home Depot will run tools and a paint gun to do body parts one at a time? Or am i looking at getting one of the 60 gallon units to do what I need it to do?

Any input would be awesome, as I am priming my wife to make this purchase in the next few months.

thanks. RR

Re: Advice or input on compressors
 

I’m planning on buying the 60gal big dog from Harbor Freight. It has good reviews and should manage to power any body tools I’ll be using.

Re: Advice or input on compressors
 

I would do a 60 gallon and if the budget allows a two stage compressor instead of a single stage.

Re: Advice or input on compressors
 

Even with a good US made 80 gallon 2-stage, you'll want more. I doubt painting w/ 30 gallon will be fun.
The fact is the compressor is just step one. Then you need an air system with hard lines, cooling, drying, filters and hoses. Then you need tools. The last two sentences can set you back twice what a decent compressor cost.
Running hot wet air through air tools and trying to paint is no bueno.
BTW I'm on my 4th or so compressor and its a (bought lightly used) Saylor-Beal 80 gallon 2-stage and air system plus tools gathered over many years. I still want more air.
This down to the red tag: https://www.compressorworld.com/5-hp...SABEgJad_D_BwE

There are good used ones out there for a big discount...

Re: Advice or input on compressors
 

>> Every time I put an extension cord on it, the breaker pops<<

The extension cord is too small, too long or both. ALL electric motors have a current rating @ a specific rpm rating. The extension can't handle the current, voltage drops, motor rpm's drop off and motor temps shoot way up, letting the smoke out.

If the compressor runs Ok without the extension cord, get a longer air hose.
Before you shop for a larger compressor, you need to look at how much you're willing to spend to upgrade the electrical.
Then, you need to look at the CFM of the current compressor and any new compressor, Then, you need to look at the CFM requirements of the tools you will be using.

You can work with a compressor that is too small, but then you have to deal with higher compressed air temperatures and very high water condensation as well as compressor recovery time.

Re: Advice or input on compressors
 

All great info. Thanks guys. I am still in negotiations with the Accountant. LOL.

Re: Advice or input on compressors
 

Find some way to inspect the tank on grandpa's compressor before using it. If it sat a few years before you got it with water in the tank, you could have a potential bomb if you ever get it to pressurize. Probably not the legacy grandpop would like to be remembered for. The smoke could be grandpa looking out for you.

One way to think of compressors is:
Size in Gallons + Max Pressure = battery.
CFM rating on pump = charger.

More of either raises the cost.
High enough CFM can lead to a need for a special 240V drop for the motor.

Most tools want 90psi at some rate of flow. As long as your regulator and hose can handle the flow, even a small unit can power a large tool, just not for very long before your pressure starts dropping off due to low air in the tank.

I currently have a 30 gallon 2HP twin cylinder single stage unit I got from Northern Tool as a refurb. If I do a long run with a small angle grinder, it will run low on air. Doesn't happen often enough to justify a larger higher CFM unit. If you are going to do painting, might be worth while to get a similar compressor pump mounted on a 60 gallon tank.

As others have said, the compressor is just part of the equation.

Re: Advice or input on compressors
 

If you are going to paint and run air tools there are at least two sanders you will need. A dual action and a random orbit palm sander. Here is a link to eastwood sanders. Take a look at the cfm a tool needs. You need more compressor than that number. I use at least 50% for head room so the compressor is not running all the time to keep up. So if a tool needs 7 cfm at 90 psi then 7X1.5=10.5. So when shopping thats the minimum I would look for. The bigger you can go the better. The less the compressor runs to keep up the less heat and water you make. That is heat and water you need to have a way to get rid of when it leaves the compressor.
Jimmy

Re: Advice or input on compressors
 

I got a 60 from Lowes. It runs just about everything I got without a problem. The issue is that it is loud as hell. My next one will be a scroll type. They are pricey but quiet and push a lot of air.

Re: Advice or input on compressors
 

Thanks guys for all the replies. Working on my wife to get the bigger one. Trying to justify the extra expense, by telling her I will be out in the garage more and out of her hair LOL

Re: Advice or input on compressors
 

This is all great advice , but why go new ,when you can find great deals on CL for used heavy duty compressors, that will out last anything made today, they are properly maintained most of the time from the installation company or outside source because it was a vital part of there operation , I picked up a 80 gal 220 v, 2 stage, Kellogg compressor for $300 , it purrs like a Kitten very quiet it fills the tank in the specs required time , been using it for about 2 years now with no issues at all.

Re: Advice or input on compressors
 

Bigger does not always equate to better. More storage is better. Here is a link to help you calculate the CFM.

chrome-extension://oemmndcbldboiebfnladdacbdfmadadm/https://mastertoolrepair.com/images/Calculating_CFM_Output.pdf

Re: Advice or input on compressors
 

Fixed link:

https://mastertoolrepair.com/images/...CFM_Output.pdf

Re: Advice or input on compressors
 

I have been checking Craigslist periodically, not much being sold around the SF Bay area that I can see. If any of the SF Bay area folks see anything, and feel the need, post away. I am not committed to new, just to something that will do the job.

Re: Advice or input on compressors
 

What is your budget? Now double it. What is your electrical connection? How much space you got? How loud of a compressor will your neighbors tolerate? You mention that you would like it to be portable, which probably means horizontal tank. What type of surface would this portability option be used on? You mention painting and live in the bay area, which means a descent air dryer, so you need to factor that in as well. Keep in mind if you buy used people are selling cause they have new, so why they selling it. Also if its 220, they may not have the thing connected so you can hear it run. Does not mean that something new does not have a noise and mechanical issue either, but it does come with tech support to vent to. Bottom line, do you homework and buy something that will do the job today and in the future. Oh and I did a quick craigslist search a there is a lot of used stuff out there, although not inexpensive.

Re: Advice or input on compressors
 

All great info. Thanks. I was hoping to stay under $350, I have room to store it, but if it is too big, Like the 60 to 80 gallon one, I need to do some rearranging. It will be used on cement, both in the driveway and in the garage.

I have a 220 on my panel for a Kiln when my wife was doing ceramics, so I don't think that will be an issue. My neighbor is an electrician, so anything I need there I think I can pay for in Beer LOL

As far as other stuff I might need, that was coming in a new post when I was ready to pull the trigger, so to speak. LOL.

I did some looking on Craigslist as well, and I found what you found, used is not that much cheaper than new in this area. So, new might be the way to go. I was looking at the one at Lowes that was posted earlier. It was said that it would handle painting parts at a time, which is what my plan is.

Thanks again for the input, I appreciate it.

RR