Confusing compressors

cbr1100xx · 8th December 2018, 13:36

Afternoon all

I currently run a small oil less 25l compressor and it is ok using centain tools but runs out of puff quite easily on others.

Looking around there is a large amount of variations out there , psi , cfm ,hp , bar etc.

Anyone got an idiots guide to what is best?

Budget will be between £300 - £400 and was thinking 100l tank.

It will be mainly used with a da sander , 1/2" buzz gun , spraying(biggest thing being a bumper) and cut off tools

Any help gratefully received

Stan

macafee2 · 8th December 2018, 13:50

cfm is the amount of air it can shift per minute, this is important
psi and bar I'd describe as the same as mm and inches, the same thing by a different name, pressure, the amount of pressure the compressor can generate when pumping something up. This again will be important as your air tools will have a working pressure
hp, horse power.

25L is small and will run out of air causing the motor will keep restarting.

Before you buy another compressor think about what you want it to do, you mention spraying, I suspect that take a lot of air.

I have a shot blaster and the compressor is 270 litres Sealey SAC1276B and this still starts every few minutes. Unless doing a lot of work at one time involving air, I'd not start mine up.

Your air tools should have a guide on what they need to run properly.

http://www.truetex.com/aircompressors.htm

macafee2

humphshumphs · 8th December 2018, 13:55

Look at SGS. (https://www.sgs-engineering.com/)

I've got one of their 50ltr 2.5hp compressors, just under 10cfm.

As already said, it depends on what you are planning to use it for. Obviously if you're spraying, you'll need filters to 'clean' the air and possibly even driers, but that's into a lot of money.

impvan · 8th December 2018, 17:28

Look for the cfm (i.e. the air consumption) of the tool you'll use for the longest duration, then at least match it.
E.g. let's say you've got a DA sander needing 6 cfm, and a wheel gun needing 10 cfm - you size the compressor for the 6, as that's needing a sustained flow of air. The nut gun only needs short bursts, the tank will handle it alone.

The other spanner to throw in: how much electric power have you got available to run the thing?
If you can only plug into a 13A socket then you're limited to about 3hp compressors off-the-shelf.

Another option is to buy just an extra cylinder, and connectit it with the existing compressor...

cbr1100xx · 8th December 2018, 17:37

Only running off a normal plug socket in the garage.
Don't think I have enough brain cells to start linking cylinders together .
The main things I will be painting are fairings and tank off the bike and the front bumper on the mg as its looking a bit tatty at the moment.
The rest of it is just general fiddling on the fleet.
Stan

Nantwich 75 · 8th December 2018, 17:55

cfm = cubic feet (per) minute. This refers to amount of air delivered.

psi = pounds (per) square inch. This refers to the amount of force generated.

The Gardner-Denver portable compressors of the 60s,70s and 80s were designated as SP600 (Standard Portable 600)or D800 (Diesel powered 800) cfm.

trikey · 8th December 2018, 19:35

A compressor should be measured on how it fairs removing a diesel crank pulley bolt.

cbr1100xx · 8th December 2018, 20:03

Quote:

Originally Posted by trikey

A compressor should be measured on how it fairs removing a diesel crank pulley bolt.

Hopefully not

Vanbursta · 9th December 2018, 10:55

Just bought this one and I can highly recommend it, it's the larget you can go on a standard 13 amp socket:-

https://www.sgs-engineering.com/sc10...air-compressor

For £239.00 they also do several different deals with accessories added.

I spent a while searching and it was the cheapest I could find a 100L with 14.6 cfm, Machine Mart do the same compressor, for £311.

https://www.machinemart.co.uk/p/clar...e-air-compres/

macafee2 · 9th December 2018, 11:13

Quote:

Originally Posted by Vanbursta

Just bought this one and I can highly recommend it, it's the larget you can go on a standard 13 amp socket:-

https://www.sgs-engineering.com/sc10...air-compressor

For £239.00 they also do several different deals with accessories added.

I spent a while searching and it was the cheapest I could find a 100L with 14.6 cfm, Machine Mart do the same compressor, for £311.

https://www.machinemart.co.uk/p/clar...e-air-compres/

sorry I think that is a bit misleading. With 240v, 3hp I think is the maximum motor size due to start up consumption. Mine has two 3hp motors and works from 240v. One motor starts and then a few seconds later the second motor starts, my compressor is 270 litres.
whilst what you say may be correct for a 3 pin plug and socket, change the plug and socket to a different type and you can run a bigger compressor

macafee2

8th December 2018, 13:36	#1
cbr1100xx Gets stuck in VW touareg Join Date: Mar 2015 Location: dunsop bridge Posts: 870 Thanks: 225 Thanked 414 Times in 235 Posts	Confusing compressors Afternoon all I currently run a small oil less 25l compressor and it is ok using centain tools but runs out of puff quite easily on others. Looking around there is a large amount of variations out there , psi , cfm ,hp , bar etc. Anyone got an idiots guide to what is best? Budget will be between £300 - £400 and was thinking 100l tank. It will be mainly used with a da sander , 1/2" buzz gun , spraying(biggest thing being a bumper) and cut off tools Any help gratefully received Stan __________________ WE WERE BOTH BORN ON THE 4th of JULY CAR DIED 15/11/2022---I'M STILL GOING (JUST)

8th December 2018, 13:55	#3
humphshumphs I really should get out more....... No longer a Rover Owner Join Date: Jan 2011 Location: As far east as you can go in the UK and not get wet feet. Posts: 2,273 Thanks: 404 Thanked 309 Times in 246 Posts	Look at SGS. (https://www.sgs-engineering.com/) I've got one of their 50ltr 2.5hp compressors, just under 10cfm. As already said, it depends on what you are planning to use it for. Obviously if you're spraying, you'll need filters to 'clean' the air and possibly even driers, but that's into a lot of money. __________________ Richard. No longer a 75 owner as my tourer made it to the moon, and died on it's way back. But 1/4 million miles ain't bad.

8th December 2018, 17:37	#5
cbr1100xx Gets stuck in VW touareg Join Date: Mar 2015 Location: dunsop bridge Posts: 870 Thanks: 225 Thanked 414 Times in 235 Posts	Only running off a normal plug socket in the garage. Don't think I have enough brain cells to start linking cylinders together . The main things I will be painting are fairings and tank off the bike and the front bumper on the mg as its looking a bit tatty at the moment. The rest of it is just general fiddling on the fleet. Stan __________________ WE WERE BOTH BORN ON THE 4th of JULY CAR DIED 15/11/2022---I'M STILL GOING (JUST)

8th December 2018, 19:35	#7
trikey Premium Trader Rover 75 Join Date: Nov 2010 Location: Devon Posts: 33,765 Thanks: 8,837 Thanked 14,831 Times in 8,030 Posts	A compressor should be measured on how it fairs removing a diesel crank pulley bolt. __________________ Lest we forget..

9th December 2018, 10:55	#9
Vanbursta Posted a thing or two Rover 75 2.0 V6 Conn Join Date: Apr 2007 Location: Stainton Grove Posts: 1,637 Thanks: 266 Thanked 406 Times in 257 Posts	Just bought this one and I can highly recommend it, it's the larget you can go on a standard 13 amp socket:- https://www.sgs-engineering.com/sc10...air-compressor For £239.00 they also do several different deals with accessories added. I spent a while searching and it was the cheapest I could find a 100L with 14.6 cfm, Machine Mart do the same compressor, for £311. https://www.machinemart.co.uk/p/clar...e-air-compres/ __________________ I am NOT a number, I am 75

8th December 2018, 13:50	#2
macafee2 This is my second home Rover 75 Saloon & Tourer Join Date: Sep 2012 Location: Lincoln Posts: 14,912 Thanks: 1,630 Thanked 3,032 Times in 2,181 Posts	cfm is the amount of air it can shift per minute, this is important psi and bar I'd describe as the same as mm and inches, the same thing by a different name, pressure, the amount of pressure the compressor can generate when pumping something up. This again will be important as your air tools will have a working pressure hp, horse power. 25L is small and will run out of air causing the motor will keep restarting. Before you buy another compressor think about what you want it to do, you mention spraying, I suspect that take a lot of air. I have a shot blaster and the compressor is 270 litres Sealey SAC1276B and this still starts every few minutes. Unless doing a lot of work at one time involving air, I'd not start mine up. Your air tools should have a guide on what they need to run properly. http://www.truetex.com/aircompressors.htm macafee2

8th December 2018, 17:28	#4
impvan Avid contributor ZT-T Join Date: Aug 2012 Location: In the trees, near Caernarfon... and frequently Aberdeenshire, and sometimes Romania.. Posts: 143 Thanks: 5 Thanked 36 Times in 29 Posts	Look for the cfm (i.e. the air consumption) of the tool you'll use for the longest duration, then at least match it. E.g. let's say you've got a DA sander needing 6 cfm, and a wheel gun needing 10 cfm - you size the compressor for the 6, as that's needing a sustained flow of air. The nut gun only needs short bursts, the tank will handle it alone. The other spanner to throw in: how much electric power have you got available to run the thing? If you can only plug into a 13A socket then you're limited to about 3hp compressors off-the-shelf. Another option is to buy just an extra cylinder, and connectit it with the existing compressor...

8th December 2018, 17:55	#6
Nantwich 75 Loves to post Rover 75 Tourer Join Date: Mar 2016 Location: Nantwich Posts: 267 Thanks: 102 Thanked 31 Times in 23 Posts	cfm = cubic feet (per) minute. This refers to amount of air delivered. psi = pounds (per) square inch. This refers to the amount of force generated. The Gardner-Denver portable compressors of the 60s,70s and 80s were designated as SP600 (Standard Portable 600)or D800 (Diesel powered 800) cfm.