Air compressor mods?

[Brandy]

I just got a new Husky 60 gal , 155 PSi, 3.7 HP compressor. What would be the result if I swapped out the 3.7 with a 5 HP motor? More PSI? Longer duty cycle? Premature wear out of the pump? Or nothing? I alsp plan to toss the old pump from the old tank and use that tank,60 gal, in series with the new one to double the air volume. Issues?

Thanks all. Ghost.

 

[1967coronet440]

I just got a new Husky 60 gal , 155 PSi, 3.7 HP compressor. What would be the result if I swapped out the 3.7 with a 5 HP motor? More PSI? Longer duty cycle? Premature wear out of the pump? Or nothing? I alsp plan to toss the old pump from the old tank and use that tank,60 gal, in series with the new one to double the air volume. Issues?

Thanks all. Ghost.

It sure what you would gain but my uncle was telling me this weekend he has his 2 compressors tied together so he can hold more air, didn't mention any issues

 

[gkent]

There will be no pressure or cfm gain. Pressure is preset and has nothing to do with the motor. Probably set at 120 PSI on that machine. With the bigger motor you could put a larger pulley on it and it would refill the tank faster but that's about it. You should have just spent a bit more in the first place and bought one that already has a 5 hp. motor.

Oh, check the voltage. The 3.7 might be 110v but the 5 hp is likely 220v.

If you hook two tanks together you'll get more volume BUT when the compressor kicks in it will run twice as long. And those ******* get hot !!

 

[Brandy]

This is a 230V unit. It.s set at 155 PSI max.

 

[khryslerkid]

Check the rpm on the five horse. I would want it the same or close to the 3.7 hp.

The compressor itself is the weak link. If it's a lighter duty compressor than one that would come on a five hp unit, it's going to have to do double duty to fill two tanks.

 

[gkent]

it's going to have to do double duty to fill two tanks.

you mean like run twice as long !!!!

 

[747mopar]

Like everyone is saying, if the motor is the same rpm there will be no difference.... maybe last longer since it won't be getting worked as hard. Dido on 2 tanks as well, more volume but will pump twice as long.
If you want more cfm you'll have to spin it faster or buy a bigger pump. What my dad did was buy 2 identical compressors (They were on sale 50% off), mostly just ran one but if blasting we'd fire both up.

 

[gkent]

This is a 230V unit. It.s set at 155 PSI max.

I just searched for a 60 gal Husky and the one I found with that HP rating says its 135 psi max.

Whether 135 or 155, at that rate I would expect it to take a very long time to refill the tank with a 3.7 HP motor simply because of the pulley ratio needed for such a small motor to drive the compressor to build that much pressure.

Installing the larger motor with the same RPM (most motors run at 1140 rpm) you can put a larger pulley on the motor and it will refill the tank faster.

The compressor is just a pump. The increased rpm will result in more heat but that's generated more from comprssion than from friction. Go for it. You'll notice the take gets quite hot with continued use. That's where a larger compressor really shines.

 

[Brandy]

Thanks, i'm looking at the paperwork. 155 psi. rated for continuous duty with a paint gun. 3.7hp, 60 gal, 155psi, 13.4 scfm@40psi, 11.5scfm@ 90 psi,fills in 7 min from empty, 240,60hz13.5 amps single phase,. I think it will do for the $ 449.00 I paid for it.

 

[Brandy]

I really appreciate everyone's input! This is however, what I could afford. I will try to sell the old one and put the money into filters.

 

[ws27]

If you spin the pump faster, you will just wear it out faster too.

Your best bet is to leave well enough alone. How ever, do you really need 155PSI? Most likely not, so you can get a lot more life out of it by lowering the max cut out. Most of the time 125 will do just fine for most air tools. Just be careful the cut in pressure is not too low, that will cause your tools to not work as well. The higher the pressure, the less volumetric efficiency, so the compressor ends up running a lot more at the high end than the low end, so if you don't need the high so high, why?

I hope that makes sense! LOL

 

[Brandy]

it does. I was merely stating what the unit is labeled to do. I know that I don't need all of it. My old one did 175psi. I rarely used it higher than 125. I got it more for dryer more oil free air to paint with and blast with.

 

[BobJ]

Here is a mod that will help and that is a aftercooler. It will drop moisture out of your air. There are some DIY videos on it also.

 

[BobJ]

http://blog.cnccookbook.com/2011/09/06/aftercooling-a-compressor-to-cut-down-on-moisture/
Here the first one that I opened ans it uses tranny coolers.

 

[gkent]

The problem is not what you use but what its set at. Set at 155 Tank pressure) it will have to work like a son of a bitch to build that pressure. If you lower the tank pressure to 120 then it doesn't have as hard of a time BUT it will run more often. Keep in mind we're talking about tank pressure - not outlet pressure. FWIW I've been using a compressor with a tank pressure of 120 for well over 25 years. I run 100 on the outlet. It easily runs any air tool and my blast cabinet with no problems and it will run a full sized sandblaster - albeit not continuously for very long BUT long enough to do anything I've ever wanted. My point being 120 max is plenty. At 155 you'd probably be too tempted to feed that to your tools and it just isn't necessary.

 

[Brandy]

The problem is not what you use but what its set at. Set at 155 Tank pressure) it will have to work like a son of a bitch to build that pressure. If you lower the tank pressure to 120 then it doesn't have as hard of a time BUT it will run more often. Keep in mind we're talking about tank pressure - not outlet pressure. FWIW I've been using a compressor with a tank pressure of 120 for well over 25 years. I run 100 on the outlet. It easily runs any air tool and my blast cabinet with no problems and it will run a full sized sandblaster - albeit not continuously for very long BUT long enough to do anything I've ever wanted. My point being 120 max is plenty. At 155 you'd probably be too tempted to feed that to your tools and it just isn't necessary.

Thank you. I understand. I don't need that 155, just stating that is what it is rated for.

 

[T2R9]

Here is a mod that will help and that is a aftercooler. It will drop moisture out of your air. There are some DIY videos on it also.

I just did this mod on my compressor. I used a Derale cooler, https://www.amazon.com/gp/product/B004XONT3E/ref=oh_aui_detailpage_o00_s01?ie=UTF8&psc=1
The cooler has -8an fittings so I just made the an lines.
The temp difference between the input and output can be as much as a 100 degrees when running. Its mounted so the flywheel cools it. I leave the dryer slightly cracked and the water just drips out of it before it enters the tank. Makes a hugh difference in the moisture in the tank. Next up is to run my steel lines.

 

[gkent]

Steel lines rust. Run 1/2" copper - its rated at over 1200 psi and is much easier to work with. I've moved my copper lines to seven different shops over 30 years !!

 

[Brandy]

So, if I run 1/2" copper up and down the wall for about 10 feet with 6 foot runs up and down and then put a water thing after that, I should be allright?

 

[YY1]

Here in super humid FL.....

My comp has pretty big cast cooling fins between the stages, and into the tank.

My paint area is two bays down, and I just have rubber hose up the wall, over the two 12' bays, and down the other wall about 1/2 way. From there, I have a 2' steel pipe with a T.

On the side exit of the T, I have a small regulator, and a cheap HF silica dryer.

On the bottom exit of the T, there is another 12" steel pipe, and another T.

Side exit of second T has a hose connection.

Bottom has 6" of pipe and a ball valve.

Paint gun doesn't get ANY water after the silica filter, and that connection is limited to the pressure setting on the regulator.

Lower connection doesn't get very much water at all because all the water falls to the bottom 6" of pipe.

Occasionally I open the ball valve, but rarely get any water.

IIRC, all that excluding the hose was about $30.

I do have a standard sediment bowl style water separator right off the tank.