I saw a thread earlier....

[andyF]

on compressors and I was just wandering.......
I have a 3hp 50 lt compressor but it just hasnt got the power for example a air Orbital sander, would getting a Air Receiver to connect as an extra tank give me that extra to power more air tools?

I know it's not welding but I bet somebody on here knows.

 

[Welderpaul]

I have the same sized compressor - it looks a monster (new as well) but doesn't seem to have much power for anything. - Anyone out there knows?

 

[weldequip]

Sorry, I'm pretty much clueless on Compressors; rtbcomp seems to know his stuff.
weldequip

 

[lexi]

I feel better..........cos guess what?

Alex

 

[Drains]

Is it a Clarke? A mate of mine, who knows the bloke in our local Machine Mart went in for a compressor for his orbital sander, and the bloke said "don't buy anything in here, they won't do it"!!.

Another receiver will give you time, that's all. The compressor will fill the receivers and you will use the air in there faster than the compressor can replace it. What to do is turn the compressor on and go and have a cup of tea. After the tea, do some sanding, then go and have another cup of tea. Eventually you will have brown teeth, a serious caffeine habit and an unquenchable desire for a real compressor with some guts. I wish you the best. Anything by Ingersoll Rand ought to sort out that itch...

 

[mini nige]

compressor

i think u will need a 14cfm compressor to run a orbital sander thats what ive got with a 150 litre tank cheers nige.

 

[rtbcomp]

Simon has got it one.

 

[BillJ]

I've been through this with my SIP compressor - 3hp, 150 litre.
Performance of the tools was pathetic and I didn't know why as I'd never owned a compressor before. I got a clue when I saw the pressure at the regulator dip really low every time I pressed the trigger on the grit-blaster. The tank had 150 litres of air in it at 8 bar and couldn't maintain any real flow at 6 bar from the regulator.

The receiver had a 1/2" fitting but the tiny SIP toy regulator had a 1/4" fitting via an adapter. When I dismantled the regulator, I really couldn't see how any volume of air at all could get through it.

I chucked the original regulator and bought a Clarke one from Machine Mart that had a 1/2" fitting and was specced at some enormous flow rate.

Problem solved

 

[Welderpaul]

BillJ, Is the regulator you refer to the silver-coloured thing screwed into the top of the tank with the hose outlets/guage on? I have the same problem and was wondering how to overcome this! The main guage on the tank shows 9 bar in the tank, but the guage on the regulator shows 4 bar at rest dropping to 2 bar when a tool is activated.

 

[BillJ]

Yes, Paul. That's the one.

I think this is the one I bought. About £20 + VAT. Although it has a 1/2" fitting, it also has a 1/4" adapter thread-locked onto it. I had to heat the adapter to melt the threadlock enough to get it off
Same with the outlets as they didn't seem to fit anything I had. My kit was all SIP, though. It depends what you have. It might just screw straight on.

Oddly, all the promotional photos I've seen of my compressor show a much bigger regulator than came fitted to mine. Mine was a CostCo special and maybe they cut a few quid by fitting a totally unsuitable regulator and making the compressor almost useless?

 

[Lippyp]

Thats a bugger as I was thinking aboout buying the same compressor from Costco, is it really that bad? If so what do people suggest as an alternative. I don't have 3 phase and anything more thn 3hp is a no no. as it has to run from a 13 amp socket. Not going to do prolonged stuff but went decent performance at a reasonable price.

 

[rtbcomp]

Another consideration is duty cycle, although a compressor may be rated at 14cfm that does not mean it will deliver it continuously all day.

I have a Clarke SE16C150 (150 litres, 14cfm) for my gritblasting. It has been fine although a little underpowered for what I need. It needed fixing when I got it (the drain valve was loctited all wrong and some gunge got into the bleed valve on the pressure switch)

 

[BillJ]

Thats a bugger as I was thinking aboout buying the same compressor from Costco, is it really that bad?

No, it really works very well now that I have fitted a decent regulator. Allow an extra £20 for a decent regulator (that Clarke regulator claims 42cfm) and it's still very good value for money. Especially if it still comes with the air-tool kit that sells for £60-70 elsewhere. I don't know about the impact wrench in the kit, though. I haven't had any success with mine but I've seen only decent reviews of it so I reckon mine's just faulty.

 

[LINEARAUDIO]

Yep, numbers are all well and good, but to run an orbital sander you need a lot of FLOW. If you've got the biggest compressor it still won't deliver its flow if there are any restrictions. A big one is the pipe inside diameter. Try blowing through a drinking staw,then cut off the same length of garden hose and try again-you'll soon feel quite sorry for that poor ole compressor!

 

[BillJ]

Indeed, the instructions for some higher-flow air tools specify a minimum bore of hose. A good impact wrench requires at least a 10mm (3/8") hose. As I've already found, the fewer bottlenecks the better.

 

[Drains]

The big bad world of back pressure...

 

[malcolm]

I've run an 8cfm airmaster for years with 50L tank. can just about manage paint spraying but that's it. I've since picked up an old 150L compressor with belt drive, but that only has a 1.5hp motor. Thinking about joining the outlets together to try some sand blasting.

Should really get around to picking something decent up, but just have a feeling that 14cfm won't be enough.

 

[rtbcomp]

I use 14cfm (plus) for sandblasting and I'd say it's the absolute minumum. At that rate my compressor will only maintain 80psi, but the 100 plus I get just after filling the tank is much more useful!

A point I made earlier about a big machine doing a small job.......if you have a small compressor working hard you will get hot compressed air, this has less mass than cold and the blasting efficiency drops noticeably. Also the hot air is more moist than cold and this can clog the mixer in the pot, more noticeable when the grit has been recycled a few times and contains a lot of dust.

I've fitted an 8 inch mains operated fan to my compressor to aid cooling and I've extended the inlet to take it away from the heat generated by the compressors.

 

[malcolm]

I'd half thought about picking up one of the 18cfm compressors from Machine Mart, but the price is getting close to a used diesel hydrovane road tool compressor from eBay - hundreds of cfm and resaleable. Though most likely won't ever get around to organising a new compressor at all.

The 14cfm ones seem a little more affordable. That could be an option, though 30cfm is often recommended for sand blasting. Guess it depends on the size of your nozzle.

 

[Lippyp]

I know a lot of guys in the USA who actually route an air intake through the garage wall with something like a K&N air filter on the end so you pull in cool air, it also apparently reduces the noise levels considerably. Obviously over here it would need to be protected from the rain etc but that wouldn't be that difficult, just a wooden housing with a little roof open at the bottom.

Of course the ideal solution is to house it outside in it's own seperate enclosure with louvre doors for cooling and maybe even an extractor fan.

Can you point me to the clarke regulator on the machine mart site? Is it this one? http://www.machinemart.co.uk/shop/p...path/air-line-equipment-air-hose/brand/clarke