Looking for an air compressor

[bonz_d]

These past few weeks I've been watching CL for a nice used air compressor. Specs would be 115v and capable of 7cfm at 40lbs., tank size of at least 20 gallon. HP unimportant.

I've come across many in this size at a wide array of prices and conditions so I have found many to chose from.

The question I have is about the pumps themselves. Oilless or oil filled. Again I have been able to locate either type.

I am mostly leaning towards an oil filled belt drive type as I believe these would be more durable and have heard they are much quieter. While the oilless ones are quite loud and have a short useful life if used alot.

The main reason I'm looking is that I'd like to try some spray painting with a HVLP or a LVLP spray gun so on this note I see the oilless pumps seem to deliver a higher cfm and would eleminate the possiblity of oil contamination to the paint.

So which pump is the better way to go?

 

[matt167]

Re: Looking for an air compressor

Oil lubricated is what you want, direct drive is likely what you will find in that size requirement but there are some belt drives that run 115V. Most of the small compressors are over-rated, and all of the oil-less compressors are overrated. How they do it is by running a small pump on a large tank, and they can output a larger CFM number than the pump can actually produce because of the volume held in the tank until it runs out. Your looking for an SCFM rating. CFM and ACFM ratings are skewed as described

A real HVLP will have trouble with the 115v units as none really have the capabilities for it. A real HVLP is around 14 SCFM draw.. However, I do know that the Harbor Freight 40716 HVLP which is really just a gravity feed HVHP gun ( same as Campbell Hausfeld basic model ) and it will run on a Campbell Hausfeld compressor with the large direct drive oil lubricated pump and will keep up.

If you can find a Harbor Freight 90234 compressor, buy it. They were made by Campbell Hausfeld, have the right pump tho they are only 10 gallon and used to retail for $119. I have used mine for years and painted a lot with it.

 

[bonz_d]

Re: Looking for an air compressor

Just doing more research on guns and I suppose the ones I'm looking at would be closer to LVLP with scfm below 7. As I now see the better guns use 10-14 scfm.

Right now I'm looking at 4 different belt drive compressors that all have dual voltage, 115/230 single phase and 1 or 2hp motors. Then there are a ton of Craftsman, Husky, Porter Cable, Cambell's, Sanborns, Air America and others with Direct Drive. Just can't see spending $100-150.00 on a used one and having it junked out in a year or so.

 

[matt167]

Re: Looking for an air compressor

You would be supprised. My Harbor Freight 90234 has been going since 2008/2009 and it only burned up a run capacitor which was an easy fix. That is running 100% duty cycle for hours at a time.. It's the type of compressor that, I would not spend more than $50-75 on used but would have no problems spending that if it did not have water in the tank and was in good shape/ tested... I have seen NIB HF 90234's for $79 on Ebay from time to time. CH makes some HF compressors ( most of the stand ups and belt drives except the big 60 gal 2 stage which is a Belaire ), they also make Kobalt compressors and the TSC brand. and Devilbiss make Porter Cable, Husky and Craftsmen

That said, belt drive gets you the ability to upgrade and repair if needed. If you need more air without 220v, you can get a gas engine and pump, just need to dbl the required hp for a gas engine on a compressor and a continuous run unloader valve.
I have been building a twin pump gas powered compressor on and off for a year now. Have all the parts but within the last year, little time to get it done because of the boat and other projects/ repairs... It should get 16 SCFM@90 PSI

 

[Scott Danforth]

Re: Looking for an air compressor

I would buy new, oiled, and with a 5hp or larger 230 volt. I hate waiting for the compressor to catch up.

 

[bonz_d]

Re: Looking for an air compressor

Scott that would be great accept for the fact that I don't have 230v service in the garage. Hence the 115v requirement! Also I can't justify the expense, $500-1000.00 for a brand new one. It's just not going to get that much use.

 

[matt167]

Re: Looking for an air compressor

This is what I would recomend. It's pretty cheap, brand new. Meets your requirements ( should be over 7SCFM@40 PSI ). If you ever find you need more, you can get a bigger pump/ motor and wire for 220V or you could get a gas engine, pump and a continuous run unloader and then just fill it up and go.
http://www.harborfreight.com/air-to...-cast-iron-vertical-air-compressor-68127.html

HF will sell you a no questions asked 1 yr warranty for about $20, or 2yrs for $50.

 

[bonz_d]

Re: Looking for an air compressor

Thanks Matt, I've got a lead on a couple belt drive compressors that I'll go look at 1st. Both are asking about $125.00 One is an older 1hp 2 cylinder Craftsman and the other is a 2hp with a DeVilbiss 2 cylinder pump.

The more I read the more I'm thinking it's not so much the compressor but the gun and again am thinking that the LVLP gravity gun might be the way to go. Might be better to spend a little more on a good gun that would work with the 1.5hp 11gal compressor I already have!

 

[gm280]

Re: Looking for an air compressor

I use a 4.5 HP 115 VAC oiled compressor and I paint lots of things with HVLP type spray guns all the time. However, I am going to buy a standup fixed position compressor that will allow me to run DA disk sanders that require 14CFMs @ 90 PSI. My present compressor only runs that air sander for about two minutes or less before the compressor kicks in and never recovers to anything usable with that air sander. Everything else will run with my present setup including a nice sand blaster and impact tools and such. Most HVLP paint guns need at least 30 to 40 PSI at the guns to give a 10 PSI spray at the spray nozzle for proper spraying. I use lots of different HVLP guns in different nozzle sizes and not one taxes my present setup... NO issues with even spraying entire cars with my present compressor setup at all...

 

[bonz_d]

Re: Looking for an air compressor

OK, I do know a little bit about air compressors as I work in the maintenance dept. were we have 3 Ingersol Rand 100hp rotory screw compressors, 1 old 20hp Champion piston and a number of small direct drive portables. The portables are throwaways to the company and I don't use them much in my daily work because I mostly connect to the IR's that are piped throughout the plant. The old 20hp is loud and cycles a lot when hooked up to it using air grinders or cutoff tools.

I already have a small 1.5hp Craftsman but it only delivers 3.2scfm @40lbs., don't think I'll be able to paint much with that one.

 

[matt167]

Re: Looking for an air compressor

My recomendation is to buy the Harbor Freight 40716 spray gun. They list it as an HVLP but it operates at 50-60 PSI. It's pretty much all I use and may keep up with your compressor without issue. It's like $10 but you can buy the CH version at Walmart and it comes with a nice case. I have both and they work the same.. If not, buy another better model compressor, hook them togther with a T and equalize the pressures to 90 PSI. Run them on seperate circuits and you'll get it done.. Running tandem you can add the CFM ratings togther

 

[bonz_d]

Re: Looking for an air compressor

Matt, I've read the reviews and watched a few more on youtube about that gun. Seems people either love it or hate it. There is also a video review on youtube for a Grizzly brand gun, about the same price ans specs that looks pretty interesting also. Looking at other guns also.

I don't have a problem with droppin a hundred bucks or so on another compressor. Just afraid of doing it on a direct drive or oilless one. Would hate to have spent the money on someone elses junk that is already used up. At least with the belt drives I can easily replace a motor if I have to. Can find these on CL all day long, some hardly used and look new for $100.00 or less.

 

[gm280]

Re: Looking for an air compressor

Belt drive compressors allow you rebuilt the actual compressor if need be with piston and rings available for those that need them. Direct drive compressors are like you said, throw away units. So buy a good cast iron twin and don't worry about it... Like I stated before I use a 4.5 HP 115VAC setup with a lot of HVLP spray guns and not one has any issue with the compressor keeping up. I use Devilbiss guns but also have an IR270 and some other not so usual types. Just get the gun to fit the job you are going to do. The gun tip size is that deciding factor, not the price... You can't expect a 2.5mm tip gun to spray a good quality clear coat or base coat paint. And the same with a 1.0mm tip gun will not spray a thicker primer coat... So read and understand what tip sizes are for on HVLP spray guns before buying something that may not work for what you want it to do. Viscosity or paint thickness has everything to do with the tip size for a quality paint job. Buying a cheap gun just because it is cheap is not conducive to a quality finish. But good (surely not the top best) spray guns don’t cost that much more than some cheap junk types… Look at TPCGlobal website for some good guns that don’t cost an arm and a leg. They have a lot of interesting videos to view also and explain how to use different guns and why… Always better to buy something that can be actually used for a little more money then to buy some useless junk that will cause more problems then it is worth...

 

[bonz_d]

Re: Looking for an air compressor

Well I located a nice old Craftsman 1hp, 20gal twin cylinder belt drive for the nice price of $75.00 that I think will do the job. A true 1hp and not one of those new over rated ones that say they're 4hp max but run at 1.5hp.

gm, I've spent the morning looking at guns and yes I've been to TPC Global website. Looked at their branded guns like the G6600 and also some Titan guns because I see that these guns have replacement parts and different size tips available. And will operate at 4-8 scfm. Was thinking that a 1.5mm tip would be a good place to start and hoping that they will spray enamals like Rustoleum and marine topcoats.

 

[matt167]

Re: Looking for an air compressor

1.0mm-1.5mm should be good for paint, and 1.8-2.0mm should be good for primer.. If all your spraying is single stage enamel, you don't need an expensive gun. It's not hard to get any gun to lay down rustoleum nice. If your looking for a BC/CC automotive finish, or anything with metalflake, your going to want something decent

 

[bonz_d]

Re: Looking for an air compressor

Thanks Matt, that's kinda what I've been reading and seeing in the online and youtube video reviews.

Have got to say I've learned quite a bit already these past few days and am getting excited about giving it a shot. Pun intended! Already have the wife looking for practice paint. She works for a company that distributes so when they get dented cans they can't sell them and it get to costly to send them back so she gets a huge discount.

 

[gm280]

Re: Looking for an air compressor

Well I located a nice old Craftsman 1hp, 20gal twin cylinder belt drive for the nice price of $75.00 that I think will do the job. A true 1hp and not one of those new over rated ones that say they're 4hp max but run at 1.5hp.

gm, I've spent the morning looking at guns and yes I've been to TPC Global website. Looked at their branded guns like the G6600 and also some Titan guns because I see that these guns have replacement parts and different size tips available. And will operate at 4-8 scfm. Was thinking that a 1.5mm tip would be a good place to start and hoping that they will spray enamals like Rustoleum and marine topcoats.

Glad to see and read you are talking about tip sizes now. You are surely on your way to a nice finish on whatever you are going to paint. Tip size is so much more important than price any day. I came across a total set of Devilbiss spray guns from TPC Global for a song on EBay and just had to take it off the guy?s hands for him. The set was given to him as some gift and sat in his garage. He never even opened the set up. So that is how I got some of the spray guns I use. While they are not top-of-the-line guns by any means, they sure beat the junk guns available everywhere with zero parts available. Repair kits are available for all my spray guns. However, just after you spray anything you have to clean the guns immediately and replace any parts that are not working properly. I actually like spraying things now? Buy quality guns (not the top-of-the-line) and you will never regret it? Also every compressor will fill up with water and allow it to flow with the air to your gun and ruin any paint job. So when you get ready to paint anything, drain the compressor first and install a moisture trap at the gun. They sell them for little to nothing at auto paint stores. And you can put them in the oven at the lowest heat setting and dry them out and use them again and again (just a little tip from the auto paint shop).

 

[matt167]

Re: Looking for an air compressor

When I paint with moderatly expensive paint ( I'v never spent over $125/gal for the paint itself and only spray SS enamel ), I use 2 drip moisture traps plus I have a dedicated Air filter/ moisture regulator that I only use for paint and the hard line to it runs up the wall and back down, and I only use one single dedicated air hose for paint. Never had a problem with moisture or contamination in a paint line.. Even my cheap guns are cleaned out completly after each and every use. I have never bought a replacement due to lack of cleaning.. I do want to get a good gun when I spray the Custom Craft tho.

 

[Scott Danforth]

Re: Looking for an air compressor

Scott that would be great accept for the fact that I don't have 230v service in the garage. Hence the 115v requirement! Also I can't justify the expense, $500-1000.00 for a brand new one. It's just not going to get that much use.

I thought that way too. Then I dug a trench and pulled 60' of 4 gauge copper to the garage and bought a 5hp, 60 gallon compressor.

 

[dolluper]

Re: Looking for an air compressor

Lots of DA's run under 7cfm's look around as for painting install a moisture filter in your line before the gun your choice where....for painting you want at least a 5cfm or higher oil or oilless drive @90lbs 110>120 v compressor20 gallon but for about 300 more bones get a 60 gallon with 14 cfm's at 90 230v.....used there are great deals.....you will love the difference