Compressor Advice Again

[Witterings]

I'm looking at a 24 ltr compressor mainly for blowing up tyres but will also use an air blow gun quite a lot and have narrowed it down to a choice of two .... Both are 24 ltr ... one has a 2.5HP motor and is rated at 8 bar, the other has a smaller 2HP motor but rated at 10 bar

I'm guessing that the one with the smaller motor will just take longer to fill especially as it's taking it to a higher pressure but once it's done the air will last longer before it cuts in to re-fill again.

Whilst I think both would be fine for filling car / bike tyres but would one be better for an air blower as I'd use this quite a lot and the higher pressure of the 10 bar may have more force and be better for blowing away muck / debris ... flip side of the same coin it may also be more frustrating when the pressure drops off as the smaller motor will probably take longer to re-charge.

I'm prettynew to compressors so any advice anyone can offer of one vs the other would be much appreciated.

[E-bmw]

Daft though it sounds it could just be the way they have worded it, links would help if that is the case.

I suspect all compressors have higher pump rating than delivery pressure or the last little bit would take forever.

[paintman]

Small compressors are usually advertised with the air delivery given as displacement which makes them look much better than they really are.
AFAIAC this is a con as the relevant figure is Free Air Delivery (FAD) which will be around 2/3rds of the displacement figure.
The smaller the tank the more you will need to keep stopping to allow it to refill to give you acceptable pressure at the blowgun.
I expect the bar figure you give will be the maximum working pressure of the compressor when the tank is full & it cuts out. It will not deliver air continuously at that pressure - you would need a very big compressor indeed to do that.

Edited by paintman on Wednesday 17th January 10:39

[Witterings]

Here are links for the 2 as suggested

The 2 HP 10 Bar one
https://www.screwfix.com/p/impax-om227-24-cm2-proe...

The 2.5 HP 8 Bar one
https://www.sgs-engineering.com/air-compressors/se...

[paintman]

Generally the bigger the horsepower the more powerful the motor & the more air it will actually deliver.
I would expect the 2.5hp to be able to deliver more air & maintain a higher pressure than the 2hp.
I don't believe that either will be able to power an air sander or grinder for more than a few seconds at a time based on personal experience of similar sized compressors.

222lt/min as claimed by the 2 hp one is 7.8cfm.

[Frankthered]

OP, did you see this article on the SGS site?

https://www.sgs-engineering.com/help-advice/air-co...

That seems really well written to me. My first question for you (honest) was going to be what is the flow requirement of the blow gun you want to use? Once you know that, and the pressure, then you can pick your compressor. If your gun only needs 8 bar, you won't really need the 10 - you might even need to use the regulator to reduce the pressure.

Did you notice that the Impax compressor is oil-free, but the SGS one is oil lubricated - don't know if that makes a difference for you.