building a frankenpressor....

[bad_idea]

i have a quincy 325 in need of a rebuild. my question is what would be the problem with mounting it to a 30 gallon tank? i know this size pump is typically mounted to a 60 or 80 gallon tank. i'm thinking shorter time between cycles meaning the pump will run more often. also the air outlet from the tank will be warmer due to less time cooling in a smaller area. warmer air will be moist air. those are the only drawbacks i see, am i missing something?

i have limited space and i also have a 30 gallon tank on hand. kind of a two birds, one stone kinda thing.

 

[plinker]

As long as the tank is rated for the max psi you have the pressure switch set for therre's no problem with using the 30gal tank.

I picked up a Husky/C-H motor & tank for 100$ and put a 10cfm Eaton pump on it.

If the tank was rated for 175 to 200psi I would have gotten a bigger pump (but would have had to upgrade to a 5hp motor as well). It's rated for 150psi, so I have it set to shut off @ 130psi.


As for the moisture problem if you have an airline system setup that will help some. Compressed air will cool while moving. A dessicant filter and/or air cooler would help too.

 

[W-Cummins]

The problem with a large pump on a small tank is that if it's too large, your going to have problems with a really short pumping cycle. This will cause problems with 5hp and larger motors, as they are only rated for so many starts per hour. If you exceed this you will have shorter motor life, and if it's excessive, you can overheat and even burn up the motor! One way to get away from this is to use a pump that can be operated from an unloader. That way you start the motor and then run the pump until it pumps up and unloads the head/s ( the motor/pump still turn) when the pressure falls below the set point the pump once again starts pumping air. If you run your machine hard this is a good way to run a compressor even its got an adequately sized tank.

William....

 

[bad_idea]

the tank is rated for 175 psi and i recently hydro'd it to 200 psi. the quincy 325 has an unloader valve, so it starts unloaded. i am sure i could set it up to continue running unloaded until needed. how would i hook this up? ideally i would have the option to switch between continuous running unloaded and shutting off when pressure is reached. i don't foresee me using it often enough to benefit from continuous running, but i plan on putting it together with room to grow.

 

[plinker]

For running continuous you'd need to have a similar setup that a gas engine powered compressor has. I dont really know much about them

 

[oilslick]

Just do it dont worry about cycling with a quincy, they freewheel better than any other I have ever seen on startup and shut down.

 

[W-Cummins]

Just do it dont worry about cycling with a quincy, they freewheel better than any other I have ever seen on startup and shut down.

I'm not sure how this effects the motor starting/overheating problem??

the tank is rated for 175 psi and i recently hydro'd it to 200 psi. the quincy 325 has an unloader valve, so it starts unloaded. i am sure i could set it up to continue running unloaded until needed. how would i hook this up? ideally i would have the option to switch between continuous running unloaded and shutting off when pressure is reached. i don't foresee me using it often enough to benefit from continuous running, but i plan on putting it together with room to grow.

Your 325 can be setup for unloaded operation. You will just have to add the pilot valve and some additional plumbing to hook it up. I'm running your pump's big brother (a 390) that way. And although mine came setup for the unloader, it's just a few more parts to add, as QT pumps already unload the head for startup and/or low oil pressure. There are 2 different types of unloader controls a LS and a LVD. I have the LVD and it works by adjusting a needle valve to set the unload pressure. You just set it too high if you don't want it to unload before the pressure switch cuts off the motor. The LS pilot valve operation is similar, but you set the pressure by screwing the valve adjustment "nut" into the body, you turn on and off the LS unloader via a toggle valve on the end of the control valve. I had to replace the valve body of my control, as it was damaged when the PO tipped the compressor over. The part wasn't too $$$ I think about $30 or so... You should get a manual for your pump (you can down load them for Quincy) as they show the different parts required for each setup.

William....

 

[Danglerb]

i have limited space and i also have a 30 gallon tank on hand. kind of a two birds, one stone kinda thing.

I'm guessing your forum name is something you earned?

Its a Bullwinkle solution, it should work, just not well. I don't think I would get into anything too fancy, just hook it up normally and see how it does. Worry about it if in actual use it cycles too often.

 

[bad_idea]

I'm guessing your forum name is something you earned?

Its a Bullwinkle solution, it should work, just not well. I don't think I would get into anything too fancy, just hook it up normally and see how it does. Worry about it if in actual use it cycles too often.

i was thinking along those lines. don't fix what isn't broke..... yet. i got the pump and motor off of cl for $100. the tank i have laying around. the rebuild kit costs around $150. call it another $50 for odds and ends, i have $300 into a compressor capable of 18.64 cfm at 900 rpms (just pulled those numbers off of google). i don't think this one is a bad idea, so far. but i have been known to chase bad ideas before. (hence the screen name) besides, at this point in the game i need a compressor for little more than filling tires. but i use mostly air tools at work and prefer them over electric.

 

[pipsters]

Speedaire I believe sold a 30 gallon 17 CFM model. If it was an issue you'd think they wouldn't have done it.

I didn't buy that model (was on CL for $300) because I didn't have 220v. I wish I had. That is my perfect compressor. Anything you do requiring the air it puts out it's going to run almost if not continuously anyway regardless of size. For other small tasks it will build up fast and shut off, no need to fill a 60 or 80 gallon tank. And, you can always plumb another one in if needed in the future.

 

[bad_idea]

My thoughts too pipsters. The funny part is I have a horizontal 60 gallon tank tucked away in a corner of the backyard. I just don't have the space in my cramped 14x20 garage.