Air receiver, compressor filter ideas.

[Rustyrangie]

Hi all.

I got one of the "Aldi specials" compressors last month. It's a great bit of kit but a bit noisy and the receiver is a bit too small.

So..... Could I use a redundant caravan gas cylinder as an extra air receiver? The one I have come by has been empty for a couple of years with the tap open.

I envisage sticking it out of the way in the garage roof space connected to the compressor with suitable pipework.

Anyone done this? Obviously I'll need to get any trace of the gas out, any special techniques for doing this?

My thoughts about the noise are to extend the air inlet, which is where most of the noise appears to come from, through the garage wall and fit the filter there inside an open box with a "roof" to keep the rain off.

Any help or alternative ideas greatly appreciated.

Thanks,

Bob

[LandyManLuke]

Have a look at Roger's post here and my page here

Yes you can use a gas cylinder as a receiver, but in doing so you'll exceed the duty cycle rating of the pump and cook it. Roger's had success in removing the valve in the cylinder etc, but I'll that for him to cover in detail.

You could use a simple valve setup to transfer air around, to preserve an acceptable duty cycle. This works as long as you work things logically. My 50L tank and 2 HP compressor takes about 4 cycles to fill the 300L tank, if i observe the duty cycle with a stop watch (ok, i do it by guess-work now).

Has your aldi special got a small screw valve on the output? my Machine Mart unit had one, and it seriously restricts output. definitely worth removing.

[nicksmelly]

How will you exceed the duty cycle of the pump? What happens when you're using more air than the receiver holds, like spraying or just using a tool continuously? I understand the compressors have a finite life, and using them in shorter stints may extend their life, but thats the same for most power tools and equipment these days.

If it's got a duty cycle, it must have some way of controlling it other than relying on the size of the receiver, maybe like a over temperature switch in the motor housing.

We run our compressor in the workshop regularly for about an hour continously with the air blow gun, and its not expired yet...

[LandyManLuke]

DIY compressors have perhaps a 40% duty cycle, rated at, I think, S3 which is approx a ten minute time frame, ie 4 mins on in every 10. There's a sticker on mine but i can't remember the exact details.

Filling a larger receiver, or indeed using a tool for a long period of time, will cause the pump to run longer than this, which will cause it to overheat. The compressor should be fitted with a thermal trip.

A workshop compressor is likely to have a higher duty cycle.

I believe the small valve fitted to the output of the Machine Mart unit i have was a crude way of limiting output volume so as to give the duty cycle half a chance of being maintained.

[nicksmelly]

Well, our workshop one is a clarke £69 jobby with a 25 litre receiver. It's about 3 years old now and is still going strong and hasn't burnt out. Thats not to say it wont, but compared to buying a proper belt driven static compressor with a huge receiver at about £300 - 400, I know which is better value for money for what we use it for. I'd rather expect to pay £69 for a new compressor in the event it does expire than spend £300 on a professional thing that I wont use to its full potential.

[LandyManLuke]

Fair enough, I wouldn't take that as 'duty cycle doesn't matter, £69 compressor will do it all' though. Horses for courses etc.

[Daz800]

Have a look at Roger's post here and my page here

Yes you can use a gas cylinder as a receiver, but in doing so you'll exceed the duty cycle rating of the pump and cook it. Roger's had success in removing the valve in the cylinder etc, but I'll that for him to cover in detail.

You could use a simple valve setup to transfer air around, to preserve an acceptable duty cycle. This works as long as you work things logically. My 50L tank and 2 HP compressor takes about 4 cycles to fill the 300L tank, if i observe the duty cycle with a stop watch (ok, i do it by guess-work now).

Has your aldi special got a small screw valve on the output? my Machine Mart unit had one, and it seriously restricts output. definitely worth removing.

Why use a gas cylinder when you can get a couple of air tanks from a hgv/psv breakers for 20 notes.

The air tanks on these vehicles have the pressure releif valve built in and all you need is some piping for connection.

I have one in my 90 and i use the other one i have as a tyre inflater when i have to check swmbo tyres .

i can recharge my 90 tank from my car inflater/ garage inflater or from my home compressor.

Darryl