I think it is time for me to upgrade and replace my air compressor. I have had an Aldi compressor for 5-6 years and although it works to a point, It is getting very tired and I think it is struggling to drive my Impact gun.

Should I go for an 8 or 10 bar compressor, what difference does it make to using the tools?
What about CFM, is higher CFM better than higher pressure.
Should I go for 50 or 100 litre tank?
direct or indirect drive, single or twin?
Is there anything in the pipe work I should look out for that could affect the performance of the tools running off it?

Looking to spend about £500

Would be nice to get something that will crack off a crank pully bolt 56 TDV8 Vogue SE
9 Freelanders, 2x 2002 TD4ES, 2001 TD4, 2002 1.8GS, 2000 XEDI, 2x 2000 1.8ES, 2004 1.8 & 2000 1.8 GS (rolled)
91 Lotus Carlton (sold)
90 Lotus Elan (BRG)

if you go into a branch of Machine Mart (co.uk) they will give you all the answers you are asking about. really you should be looking at a 3hp twin pump. some are direct drive, and some (better) are belt, but it depends on space. my advice on a 3hp, you have to modify the garage fusebox with a sepate type of fuse/breaker, with motor start qualities, this stops it tripping when starting up when half empty, many people have all sorts of issues, and trip all the electrics indoors etc. they sell startboxes, but speak to an electrician. i have a D rated 20amp i think, in my mini garage unit. just for the compressor. if you dont, you run risk of overload your mains, and risk trashing the motor i'm told. 3hp is the max for a typical houshold, you can run all tools etc. you can buy them secondhand, but they are often very tired. get 100 litres min. 14cfm is about as high as you can get. you might have some change from your £500 im sure. get a better regulator, and some hoses. -plenty of stuff in machine mart shops to spend the change on. i have a 200litre 14cfm twin upright belt. single phase 3hp thats as big as you can typically go. unles you want giant tank. though i think they go outside the £500 a bit.

Thanks, no local machine mart, but can always mail order. Electric shouldn't be a problem as I have the main box in the garage and its 2 cables and 2 meters. 200 amps I guess. Got sparky in at the moment replacing generator hook up so will get him to pop in a 20amp box for the compressor.

so looking for 14cfm, 10bar, twin with belt drive. sounds too easy or more than £500  56 TDV8 Vogue SE
9 Freelanders, 2x 2002 TD4ES, 2001 TD4, 2002 1.8GS, 2000 XEDI, 2x 2000 1.8ES, 2004 1.8 & 2000 1.8 GS (rolled)
91 Lotus Carlton (sold)
90 Lotus Elan (BRG)

Check, check and check again - before you buy!!

You're unlikely to get a compressor delivering 14cfm @ 10bar driven by a 3hp motor. Manufacturers mix things up to confuse the unwary.

Check that the compressor you choose does not give a cfm figure based on "free air". This is basically the volume of air the compressor will move at zero pressure (i.e. into free air). An inefficient compressor may have a good cfm into free air but that may be 1 or 2 at 10bar.

The larger the receiver the better really. If you need high cfm for a short period then a poor compressor with a large reservoir can often suffice.

Remember, very few pneumatic tools require more than 7barg so the extra 3 you're talking about is only there to help with stored air. For impact wrenches etc you need instant air rather than length of delivery. Therefore, don't try and run a 1/2" impact wrench via a 1/4 bore hose - it'll be pants!!!!!!

Belt drive is the way ahead btw - although it does add a fair bit to the start up load

Think I am the unwary. just been looking at SIP catalogue and all the CFM is piston delivery so guess that will probably be what they deliver at zero pressure. Hadn't really looked at the pipe work, but 90% sure the stuff I have at the moment is 1/4bore hose.

Think I will invest in some 3/8 or 1/2 bore hose 56 TDV8 Vogue SE
9 Freelanders, 2x 2002 TD4ES, 2001 TD4, 2002 1.8GS, 2000 XEDI, 2x 2000 1.8ES, 2004 1.8 & 2000 1.8 GS (rolled)
91 Lotus Carlton (sold)
90 Lotus Elan (BRG)

I have a 23CFM compressor which is powerful enough to not require any air tank for storage, the only downfall is it runs on a 3 phase motor. However if you live in an older house there is a chance you have 3 phase coming into the building but it will not be connected so worth checking

This looks like a top piece of kit that should last you forever

Click


If you do have 3 phase available the best compressors are the old type with slow running motors and cast iron compressor bodies, with a little care they last forever and are very quiet.

This is a cast iron bodied 1968 Ingersoll Rand compressor I bought a number of years ago, a little slow for me but I keep it as a back-up incase my Hydrovane ever breaks down

Click

Don't forget that so long as the motor is dual voltage you can run a 3phase unit via an inverter which will also remove start-up load spikes.

47p2 - Screw compressor would be great, that one is in Cornwall

Going to try and stick with 240v single phase if I can, I don't really understand 3 pahse

Local place has one of these, are SIP good or
http://www.sipuk.co.uk/sip-06260-airmate-t...essor.html 56 TDV8 Vogue SE
9 Freelanders, 2x 2002 TD4ES, 2001 TD4, 2002 1.8GS, 2000 XEDI, 2x 2000 1.8ES, 2004 1.8 & 2000 1.8 GS (rolled)
91 Lotus Carlton (sold)
90 Lotus Elan (BRG)

I personally wouldn't buy SIP, they are made in the far east and in my experience cheaply made and don't last, but that's only my experience

Just to cheapen this thread I think Aldi had some 3hp twin cylinder compressors in for £169.00 last week

I know.....you pay for what you get, but......at £169.00 they're disposable

Always good to know if there are quality issues, they claim to be made in Italy, which gave me a concern on their build quality  56 TDV8 Vogue SE
9 Freelanders, 2x 2002 TD4ES, 2001 TD4, 2002 1.8GS, 2000 XEDI, 2x 2000 1.8ES, 2004 1.8 & 2000 1.8 GS (rolled)
91 Lotus Carlton (sold)
90 Lotus Elan (BRG)

My GF want to go to Aldi, so will see if they have any left and take a look, the one I currently have is an ALDI single cylinder, which has lasted 6 years, was after more air, which maybe the twin cylinder has 56 TDV8 Vogue SE
9 Freelanders, 2x 2002 TD4ES, 2001 TD4, 2002 1.8GS, 2000 XEDI, 2x 2000 1.8ES, 2004 1.8 & 2000 1.8 GS (rolled)
91 Lotus Carlton (sold)
90 Lotus Elan (BRG)

Andy_J wrote:

Always good to know if there are quality issues, they claim to be made in Italy, which gave me a concern on their build quality

Great thing about Italian stuff (or was back in the day) is that they tend to switch neutrals instead of lives. Makes live fault finding interesting


If you're just needing more umph to occasionally run an impact wrench you could always simply add a larger receiver after your compressor (gas cylinder ) and then make sure you have full flow to you equipment. The compressor will get hammered trying to fill the extra storage but you only need to plug it in when required and then just use the standard unit for lower requirement jobs.

Hmmm - not sure I've explained that very well I'll shut up now