Compressor Newbie

[Onoff]

I'm a complete newbie to compressors. Bought an Aldi 2.5hp one a while back. I only really use it for tyres and blowing dust off stuff. I did try media blasting and when it all came together and worked it was excellent. I think though I had a moisture issue though. Brings me onto my next question.

Went to use the compressor the other day and it just hummed then cut out. It did that straight out of the box but got better. Took a few goes of trying it and hitting the reset for it and still wouldn't fire up.

I undid the drain underneath and got quite a bit of rusty water come out. It fired up alright afterwards.

I have, periodically drained it but only really got a blast of water spray and never rusty. Maybe I haven't done it for a while...

My questions then are what is compressor "etiquette"? Should I drain after every use and leave it open?

I've heard of people making "dryers" out of copper pipe. Up for that if anyone can point me in the right direction please. Long term I'd planned to leave the compressor in situ in the garage and run a fixed air line to the front outside the garage where the cars park.

The compressor btw has oil in it according to the sight glass.

At this point what should I do to service the compressor? Can I "blow" oil through it?

Cheers

 

[Rayf]

are you switching it on/off by lifting/pressing the red button on the pressure switch?

 

[brightspark]

its only light duty and not suitable for blasting it will overheat and kill it off thats why its producing a lot of water

 

[Longhorn6120]

I too would be keen to hear the best ways to keep a compressor in good shape. I have a small 25lt one I use for light duty work like tyres, etc, but I also have a 100lt 3hp model I bought for blasting. The big one has barely been used thus far waiting forever a permanent home, so any advice on etiquette would be welcome here also.

 

[RWD3M]

I'm no expert but I run mine regularly (weekly at least, though usually more often), drain the water regularly (again minimum weekly), and don't drain it down for no good reason.

I change the oil and filters every year and have had great service from it over the last 12 years.

It's this one:

 

[Onoff]

are you switching it on/off by lifting/pressing the red button on the pressure switch?

Yes I am.

 

[Jbo2231]

Unfortunately air is one of the most "expensive" ways to power tools/do things with, you're almost always better off using electric tools unless you already have access to a high CFM compressor, or have the work load to justify getting a large compressor.
Any compressor under roughly 18cfm will struggle with blasting stuff with media, and even then it will struggle to keep up if you're blasting at a decent rate.

You want to focus on the CFM your compressor provides rather than the reservoir size. Think of the CFM as equivalent to how quickly you can fill the tank, and your tank size as being the amount of air available.

If you cant fill your tank at the same rate or quicker than you are using the air then you will eventually run out..
Compressing air causes heat, the longer you have the compressor running the hotter it gets due to the motor running and the continous compression of the air.
You want to be in a situation where your tool uses less air than the compressor provides, that way your compressor gets to rest for a while before kicking in again. A larger tank can help to extend this period where your compressor gets to rest but unless your compressor produces more air than your tool needs you'll likely still end up damaging a low cfm compressor unless it is designed to run continuously. Even if it can run continuously you will still need to stop and wait for it to catch up when your pressure drops below a usable level.

Now to answer your question it depends on how often you are using your compressor and how much stress you put on it. I drain my tank weekly, it is a dual 18cfm motor unit with a 250L tank. It's used for blasting and for powering high CFM tools such as grinders and Sanders. The reason for draining the tank is primarily to maintain that 250L reservoir space but also to protect it from rust when it is not in use for a few days/weeks. I do it weekly due to it being in use so much.

If you have a smaller unit that only kicks in once or twice a day you could probably get away with a monthly empty of the tank as you're likely not compressing enough air to cause enough heat to produce the humidity required to produce large quantities of water.

It's the same situation for oil.changes. if you are using a compressor for more than it is designed for you want to increase your maintenance of it if you want any hope of a long service life.
I change my oil every other month as 5L of it costs around 25 quid and each unit only takes around 200-300ml. Complete overkill on my part but the oil wont be usable in a years time after it's been open that long, may as well use it!

 

[Seadog]

You want to focus on the CFM your compressor provides rather than the reservoir size.

If it hasn't already been mentioned, beware of claims about CFM capability. Very often, unless you're buying an industrial sized unit, they will quote a 'free air' flow figure. This is not the CFM when the unit is at pressure and will be well below what you are expecting when in use.