Which compressor?

[h3rman]

Right, looking at getting a compressor & some air tools to make life a little easier when working on the car, and might be used occasionally for spraying the odd bits & bobs.

Will mainly be used for things like impact wrenches, etc. Have asked on other forums, but looking for a bit more advice that hopefully some folk on here can provide.

I'm looking at this SIP air compressor or this airmaster compressor. Which one would be best/most reliable and would they be enough to do what I want it to?

When I say spray little things, I mean nothing bigger than an alloy when refurbing them. Also, I've noticed you can get DA's that work with them, so would be handy if I could sell my Kestrel and get an air powered one to make a bit of money back.

Would this DA be up to the job, or would it be best to just keep the Kestrel. Not too fussed if I end up keeping it, but thought it would be nice to sell and get a few quid to put towards the compressor. Main thing I want to know is if that compressor would be up to the job of spraying things like alloys and running a selection of air tools like impact wrenches, drills, cutting tools, etc and which one out of the above 2 should I go for, or is there another one that's even better which I should have a look at?

Cheers!

 

[jaykay]

both compressor are nearly the same. think i'd go with the sip.more chance of spares from them.
they are just about up to the job,(bigger the better).
da is ok,thing with air tools is to lub them daily,or they dont last long.
oh and backing pads can be distroyed easy in the wrong hands.

 

[pedrobedro]

I have an older version of the SIP with the same spec. It hasn't had a hard life but it has never had any problems. Tools like cut off disks, DAs and die grinders are a waste of time, the compressor will be running almost continuously but if If am spraying at 40-50psi the compressor will fill the tank with the gun still running. I have sprayed a few cars and numerous panels and repairs with good results using it with a cheap gravity gun.

 

[h3rman]

Cheers mate, was leaning towards the SIP myself for that very reason, also, can't find any sort of info on the manufacturer of the other one.

What exactly do you mean when you say they are "just about" up to the job? Don't want to be stopping and waiting for it all the time when running air tools, or even worse, when spraying!

Also, would I be able to use it for a little bit of sand blasting? I know sand blasting uses A LOT of air, but I wouldn't be blasting any more than an alloy wheel at a time, and I can wait for it to re-fill during blasting, but don't want to have to wait for it when spraying, using impact wrenches, drills, DA Sanders, etc.

Cheers!

EDIT: pedrobedro posted while I was typing! Running a DA Sander isn't a must have, because I already have an electric operated on. However it would have been nice.

 

[tigler]

Check out this thread ,
http://www.mig-welding.co.uk/forum/showthread.php?t=18020

 

[tigler]

And another thread for you !! You can see this is a FAQ !!

http://www.mig-welding.co.uk/forum/showthread.php?t=17120

 

[h3rman]

Cheers, just had a look. Might pop down to my local Costco and have a look at that SIP one that was mentioned in the first thread you linked.

You mention F.A.D, the SIP one I linked to above has a 14 CFM piston displacement and 9.5 CFM F.A.D, would that be adequate to run the things I want?

Cheers!

Also, with regards to a second hand compressor, all the ones I have seen are collection only, and all are down in England. I'm located in the NE of Scotland.

 

[tigler]

To determine if you have enough CFM FAD check the spec of the air tools you plan to use , the required CFM is normally indicated. I would say 9.5 CFM FAD will be ok for most stuff you are likely to use , DA's , angle grinders and blasting are the heavy air consumers.

 

[BillJ]

I bought that SIP 150-litre compressor from Costco some 3 or 4 years ago. Although it doesn't see heavy use it's been absolutely brilliant, except for the tiny regulator on it that was restricting airflow and making it hard to use high-consumption tools such as my spot-blaster. I replaced that with a 1/2" BSP Clarke regulator from Machine Mart and run all sorts from it, including a DA sander. Even with a 150l receiver and 3hp motor, I couldn't sand down a whole bonnet without having to stop for the compressor to catch up! It does everything else I need, though, and has no problem keeping up with my HVLP spray-gun.

The Costco one is a belt-drive unit. I chose this deliberately over the direct-drive ones because of noise considerations. The direct-drive units are really very, very noisy. The SIP belt-drive compressor (the 50l version of mine, I think) came out quietest in some magazine test or other. It's still not what I'd call quiet but everything's relative. And belt-drive ones are said to last longer because the piston speeds are lower.

The tools that came with it at the time are pretty good too, except for the impact-wrench which, in common with every other cheap impact-wrench I've come across, can't undo a properly-torqued wheel-bolt. Although I rarely use it, when I've needed the air-ratchet I've really needed it.

 

[tigler]

Yes , regulators , thats a good point. Thats one of the ways the initial purchase price is kept down , by fitting a cheapy reg. Thats the first mod to do on hobby puffers. My personal preference is to fit an FRL , filter / regulator / lubricator. Select one with an additional outlet before the lubricator stage , this can be used for tyre inflation and blowing off etc.

 

[jaykay]

"just about" meaning you will just get by with it,but will have to stop at times for tank to fill.
all the above are saying that too.
the da has a small knob on the side,that adjust air it uses. but that in turn slows it down.

 

[tigler]

Another important issue if using an undersize compressor to operate DA's and such is duty cycle. These budget hobby puffers aren't really intended for continuous use , so they should be allowed to rest for a while if being used for a heavy DA session !! I wouldn't go more than 30 mins continuous without a 10 or 15 min stop.

 

[h3rman]

I bought that SIP 150-litre compressor from Costco some 3 or 4 years ago. Although it doesn't see heavy use it's been absolutely brilliant, except for the tiny regulator on it that was restricting airflow and making it hard to use high-consumption tools such as my spot-blaster. I replaced that with a 1/2" BSP Clarke regulator from Machine Mart and run all sorts from it, including a DA sander. Even with a 150l receiver and 3hp motor, I couldn't sand down a whole bonnet without having to stop for the compressor to catch up! It does everything else I need, though, and has no problem keeping up with my HVLP spray-gun.

The Costco one is a belt-drive unit. I chose this deliberately over the direct-drive ones because of noise considerations. The direct-drive units are really very, very noisy. The SIP belt-drive compressor (the 50l version of mine, I think) came out quietest in some magazine test or other. It's still not what I'd call quiet but everything's relative. And belt-drive ones are said to last longer because the piston speeds are lower.

The tools that came with it at the time are pretty good too, except for the impact-wrench which, in common with every other cheap impact-wrench I've come across, can't undo a properly-torqued wheel-bolt. Although I rarely use it, when I've needed the air-ratchet I've really needed it.

If you don't mind me asking, how much did you pay for yours? Will be going to Costco tonight with my mate (don't have a Costco card) to have a look and see what they have on offer, but if you could give me a rough idea, that would be good.

Can't really justify more than £300 for the compressor alone TBH. The biggest things I would probably sandblast would be a wheel (about 17" in diameter).

Another important issue if using an undersize compressor to operate DA's and such is duty cycle. These budget hobby puffers aren't really intended for continuous use , so they should be allowed to rest for a while if being used for a heavy DA session !! I wouldn't go more than 30 mins continuous without a 10 or 15 min stop.

Yea, have heard about duty cycles and that it's not good to run them continuously. Something like sandblasting I would only do maybe once a year or less. Currently have 4 wheels that I would like to blast, refurb and spray, but once they are done, prob won't need to blast again. Also, there is no rush to finish them, I have from now till October to get them done.

Have seen some sandblasting equipment like this that uses 10 CFM, and gritblasting stuff seems to use around 11 CFM.

Would they put the 9.5 CFM F.A.D compressor under too much stress, or could I still use them safely, providing I leave the compressor to rest after about 30 mins of use? I know the compressor will be constantly catching up, but I can deal with that, providing it only does it when sandblasting. With regards to the DA Sander, I have an electric one anyway, so will just stick with that.

cheers!

 

[tigler]

When the air demand is close to or more than the compressor can supply and once the reservoir in the receiver has fallen below the cut in pressure the compressor will be unable to maintain the working pressure so available pressure will just continue to fall.
This means the compressor will just work continuously , so the pump and motor will thermally saturate and not be able to maintain a safe working temperature. Unless it is allowed to rest so that the excessive heat can dissipate then over time the pump will wear prematurely and the motor's insulation will break down.
If you can blast in short working sessions and allow rest periods then it's fine.
Obviously some compressors will cope better then others with this abuse , it just depends on how good the original design and materials of a given compressor are.
Think of it like driving a car flat out continuously , most would fail within a matter of a few hours , some within much less than that !!

 

[BillJ]

If you don't mind me asking, how much did you pay for yours?

Well, it was complicated since my mate with a Costco card had offered to pay half in payment for the cost of repairing my car after he'd pranged it so I can't quite remember but I think the total was around £330 including VAT. That also included one of these:
http://www.halfords.com/webapp/wcs/..._productId_158895_langId_-1_categoryId_165557
which Halfords are selling at £150
The tools aren't bad at all, actually, except as I mentioned earlier that the impact wrench seemed a bit weak. The ones in the Halfords link look slightly re-styled so perhaps the tools work better too?

If any of those tools will be useful to you (and if they're still included in the package) then it effectively reduces the price of the compressor.

I only bought an air sander because it was cheaper than a decent electric one. Had I already had an electric one I wouldn't have considered replacing it.

The Clarke regulator added another £25 or so.

 

[h3rman]

When the air demand is close to or more than the compressor can supply and once the reservoir in the receiver has fallen below the cut in pressure the compressor will be unable to maintain the working pressure so available pressure will just continue to fall.
This means the compressor will just work continuously , so the pump and motor will thermally saturate and not be able to maintain a safe working temperature. Unless it is allowed to rest so that the excessive heat can dissipate then over time the pump will wear prematurely and the motor's insulation will break down.
If you can blast in short working sessions and allow rest periods then it's fine.
Obviously some compressors will cope better then others with this abuse , it just depends on how good the original design and materials of a given compressor are.
Think of it like driving a car flat out continuously , most would fail within a matter of a few hours , some within much less than that !!

Cheers, if need be I can happily blast in short sessions and allows the pump time to rest. Like I said, will hardly be used for blasting, and have several months to blast, refurb and paint the wheels I have lying around just now.

Would probably use it till the pump comes on, then wait for it to fill up, then use, then wait, etc for about 30 mins, then let it rest for about 20 mins before going back. If I can do it like that safely, then that suits me fine.

Well, it was complicated since my mate with a Costco card had offered to pay half in payment for the cost of repairing my car after he'd pranged it so I can't quite remember but I think the total was around £330 including VAT. That also included one of these:
http://www.halfords.com/webapp/wcs/..._productId_158895_langId_-1_categoryId_165557
which Halfords are selling at £150
The tools aren't bad at all, actually, except as I mentioned earlier that the impact wrench seemed a bit weak. The ones in the Halfords link look slightly re-styled so perhaps the tools work better too?

If any of those tools will be useful to you (and if they're still included in the package) then it effectively reduces the price of the compressor.

I only bought an air sander because it was cheaper than a decent electric one. Had I already had an electric one I wouldn't have considered replacing it.

The Clarke regulator added another £25 or so.

See, I can stretch the extra £30, even if it doesn't come with tools, but can't afford to spend the likes of £400 - £500. 150L tank might be a bit on the big side (don't know where I would put it), so a 100L tank might be more ideal, and a smaller tank will prob mean it will be a little be cheaper too.

Having looked at that tool kit, there are a few things in there I could make use of, but if the impact wrench isn't up to the job I'll just buy one that is.

Cheers!

 

[rtbcomp]

.........Have seen some sandblasting equipment like http://www.machinemart.co.uk/shop/p...t/path/sandblasting-equipment-and-accessories .......

Save your money and buy a Clarke SB4 and a bucket.

 

[h3rman]

Save your money and buy a Clarke SB4 and a bucket.

Cheers, only £18 for one of those from Machine Mart.

Requires 15 CFM tho! However, that's at 6.5 bar.

Actually, that's given me another question. Say I were to buy the SIP one I linked to in my first post. It has a 14 CFM displacement and 9.5 CFM free air delivery @ 9 bar. Now if the tool operates at a lower pressure, then roughly how much free air delivery would the compressor be able to supply?

Say at 6 bar, would the compressor be able to deliver more than 9.5 CFM if that's what it can deliver at 9 bar?

cheers!

 

[rkde]

I have the SIP 3/50 compressor and I have to say I have been very pleased with it! Had it for about 8 months now and had to take the heads off when I forgot to put the filters back in after cleaning a nice simple machine

Only problem I found is the plastic cowling around the fan breaks quite easily. apart from that it does everything I ask of it ~ paint spray, sanding, work shop tools etc.

 

[h3rman]

I have the SIP 3/50 compressor and I have to say I have been very pleased with it! Had it for about 8 months now and had to take the heads off when I forgot to put the filters back in after cleaning a nice simple machine

Only problem I found is the plastic cowling around the fan breaks quite easily. apart from that it does everything I ask of it ~ paint spray, sanding, work shop tools etc.

EXCELLENT! Just what I was looking for.