Which Compressor

[Norman Verona]

Need to decide about the air compressor for the bulk buy.

It's either a 2.5hp 50 litre tank or a 3hp 150 litre tank.

the 3hp is £370 at Machine Mart

The 2hp is £211

Both are single phase

I feel that we will get "best value" with the 3hp. It's the one I would go for.

What do others think?

[Richgm]

Bigger is better IMHO.

I brought a 1.5hp 25 Litre one some years ago.

As I looked into using air tools more I found that I should have got a bigger one as mine isn't man enough to run some tools.

Look at the CFM and then look at the tools you may want to buy in the future and see what they need to run them.

Rich

[Norman Verona]

Rich, My experience and thoughts exactly.

The air riveter is Ok on my 25 litre unit but the air drill and air ratchets and guns keep it running constantly. And it loses!

[highwayman]

What cfm is the 3 HP 150l?

[KerryS]

Not that I want one, but as said the smaller one would probably have difficulty with high air usage tools. My 1.5hp, 6cfm 25 litre is fine for the riveter, tyre inflation, bit of spraying but I borrowed a right-angle drill for it and it was a slow process waiting for the pressure to build up for a 15 second bit of drilling follwed by another wait for it to recover.

Maybe another consideration is which have wheels? Though I suspect the 150 litre one will be floor mount.

[Bananaman]

I might well be interested in this BB, however i do have an issue with space and would be interested in the overall dim's of these units?

Would the 2.5hp/50L be all that much disadvantaged over the 3hp/150L

I understand that 1.5Hp/25L might well be a pain in the    when using drills etc but would this be the case with the 2.5hp/50L unit

[pistonbroke]

I'm trying to think why and where I would need to use air tools  

[supersix]

Looking at the Machine Mart specs, the 2.5hp 50l one claims 12.5cfm, the 3hp 150l one 14cfm.  The air grinders and drills they sell seem to only claim to need 4-6cfm.  So is there more to it than this?

I've got not a lot of space, and would have to move it around occasionally, and at 1.4m long, 122kg and no wheels, something like the 3hp one would be right out for me.  If the 2.5hp one is 1/3 of the weight, 1/2 the size and has wheels (as the MM one) and would be up to the job, I'd be in.

Andy.

[Norman Verona]

Sorry, missed the earlier questions.

I've asked:

QUOTE

This is a 3hp 150 litre compressor http://www.machinemart.co.uk/shop....pressor

And this is a 2.5hp 50 litre unit http://www.machinemart.co.uk/shop....pressor

Can you price as near as possible for me and I'll choose one to offer.

When he stops playing games and answers I will be able to see realtive value.

Many have asked for the larger one.

The cfm quoted on air tools is a minimum requirement. My air drill will run on my small air compressor but the compressor is running all the time and runs out of pressure on continuous use.

The larger tank will drive the "hungry" tools longer between recharges.

[alan dixon]

I am lead to beleive, that a 50ltre tank is the min, I would be happy with the 2.5HP comp, I think the other may be too big

[Norman Verona]

Alan, I suspect that if the 50 litre is best value (it may be as it will be a higher volume unit) then many will later regret we didn't go for the larger tank,

The problem is that once youi get these things you start getting tools to use with it. As the tools become more sophisticated you need larger air reserves.

Lets see what the prices are.

[a4gom]

I'd be interested in the small one there is no way I could fit the big one in the garage.

My existing 1.5hp won't run the tools I have, I'm not that bothered about the tank size, the 2.5hp motor is good enough to run everything I need for diy and for the amount I'd use it i'd be happy for the motor to be running all the time if that was what was required.

[highwayman]

I'd definitely be interested in either then

Thanks

Dave

[Mal]

Real Compressor Capacity.

Machine Mart quote compressor displacment in

CFM, which does not give a true indication of the

useful pumping rate of the unit.

CFM is the swept volume of the compressor multiplied by the pump speed.

This does not take into account the efficiency of the

compressor ans its ability to breath.

The more valid figure is Free Air Delivery (FAD), which is

a figure for the actual volume of air compressed per minute. This figure is typically 66% of the CFM figure.

Other compressor suppliers usually quote both figures.

HTH.

Mal

[ChrisG]

Can you not get an upright 150L one, as I think most of us would be able to store a larger upright tank than a conventional one that will take up about half the back wall in most people's garages?