I have a 1950's Brunner that I seized up about 10 years ago due to the oil stain on the sight glass leading me to believe it had oil...well it didn't. Of course this happens when your in a the middle of a paint job. I rushed and purchased a 5hp V-type compressor head from Harbor Freight. I had to re-drill some holes and reduce the motor pulley from 6" to 3" to get enough power to turn the compressor over. I did not realize that my motor was only 2hp so i had to reduce the pulley size and therefore the speed has decreased. I have a little 10 gallon Craftsmen that I use all the time and only fire up the Brunner for painting a car (3 times in 10 years). I bought an old Clark Planeloader Fork lift last fall and would like to sandblast and paint this spring. The air compressor has a 60 gallon tank and takes about 15 minutes to build 125psi. It can not keep up with the sandblaster. A new 5hp SPL is a couple hundred bucks, while a "Real" 5hp can be $500 plus. Should I buy a $139.00 Harbor Freight 3hp head or try to find a used 5hp.
Maybe this will help. Lots of factors involved. https://www.bigrentz.com/how-to-guides/size-air-compressor-sandblasting I can't find a HF compressor for $139 but I am guessing that that kind of money won't get near the flow rate you need.
You'll need a minimum of a 5HP unit AND it had better be two-stage, not the typical single stage if you don't want to be constantly waiting for the compressor to build pressure. Sandblasters need big volume (20 CFM or more) at 100+ PSI if you want any chance of blasting continuously. This usually means a 7HP two-stage compressor, which will also need a dedicated 40-50 amp electrical circuit.
best rule of thumb: always get more than you think you need-and rate it with scfm, not pressure. For paint, blasting, etc. 60 gal. is right.
I sandblast and paint with my 5hp 90 gallon tank air compressor it home and it's to small. Small tank helps insure there is water problems painting or blasting and the 5hp motor just isn't enough for blasting. Next time 7.5 hp 120 gallon.
For as often as you sandblast you might look into renting an industrial compressor or farming out the blasting. Focus your money on a compressor to paint with and do your normal maintenance. I tried pressure blasting with my big (maybe 60-80 gallon) two stage 5 HP compressor and spent more time waiting to fill the tank, letting the compressor cool down, than I did blasting. I called an outfit that did mobile blasting, they came with a tow along compressor run by a Ford deisel engine, they finished 3/4 of the job I had left in less than an hour. I’d spent 4 hours getting it to that point. Plus I didn’t have to wear a hood and duct tape up my coveralls anymore
In truth damned few electric air compressors can keep up with a sand blaster even a cabinet. We had a 5 HP 80 gallon 3 phase compressor in the school shop where I taught, and the blast cabinet would run it out of air all too quick.
That is too true. I've got a Champion 80 gallon 5 HP and it pretty much runs all the time when I'm using the blast cabinet. It will catch up and kick off then just a few minutes later it's right back on again. Catching up isn't a quick process either.
Just leave the forklift in patina shape. It `ll be worth more when reselling. Cause patina is all the rage. Saves on upgrading compressors. It solves two problems at once. But that`s not what you wanted to hear.
Two addional factors are the pressure you use to blast and nozzle size. I usually set my regulator at about 60 psi and it helps me avoid warping sheet metal. At this pressure, I'm working hell out of my 5 HP I-R T30 but it does keep up with me. Sorry but I don't know my nozzle size off the top of my head. Sandblasting is shitty work, especially when you're not professionally equipped. I do small jobs but farm out the large jobs out to a local pro.
I used to use my portable 105 cfm Sullair Compressor to blast my heavy equipment for painting. All I needed to worry about was the sand pot running out. I could blast a medium size dozer in a very short time. Don't wast your money. Go rent a compressor.
When you run a compressor, it also generates heat and moisture.......both of which are bad for painting or blasting. You need to get a two stage 5hp (or 7.5 hp) with an 80 gallon tank and a decent water separator mounted "at least" 10 feet from the compressor. Its just a matter of buying the proper components rather than trying to scrape by and fighting an underpowered system.
I had to replace my compressor a couple years ago and called Portland Compressor and bought this. 5 HP, 1850 RPM and IR electronic water cooler. I built the cooling tower with water dump that is installed in between the compressor and the cooler. The regulator knocks down the pressure for my air tools and there is another water separator/regulator that I use in line for painting just for added insurance. The compressor is now mounted on rubber feet but next to them in the picture is an eclectic water dump that empties the tank of moisture every hour (now routed outside) and the water cooler does the same every half hour. Needless to say, no water in this set up.
Anybody have there compressor mounted outside or under a work bench.,,mine is in the garage but is to small. I have been looking @ the Eastwood Elite QST 30/60 Scroll Air Compress pricey but it will fit.
I bought that 13 years ago for the other compressor. I don't recall where I got it. It is 110, and has like 6 options for when to drain and how long to drain. I have it set every hour for 5 seconds. In the pic it was originally just pointed onto the floor inside the shop and when you open that tank with that much pressure it kicks up a cloud of crap from off the floor and it you happen to be primering when that happens...well you can guess my reaction. It is something like this I found on-line just now. I think I paid more than that tho
Clark plane loader !! you bought a BEAST !! sand blasting is a pain , I had a 100 gallon 2 stage “binks “ compressor. mans sandblasting was maybe 1 minute of use then 10 minutes for the compressor to charge back up And your beating the crap out of it as it’s running far to much and far to long .
the horsepower ratings on compressor motors are always wrong unless you get a very good compressor. my "5 HP" craftsman motor could not run my new Quincy pump up to full pressure without popping the breaker. my 5 hp Baldor has had no problems since I added that. *my Baldor/Quincy set up could run forever sandblasting. it would cut off after about 30 seconds when I stopped.
I broke down and hired a mobile blast guy that is known for doing cars, showed up with dedicated rig, 4 media types for different areas and went to work. Very happy. What I spent was worth it. I have a big compressor and blast cabinet that I fight with to do smaller stuff.
I've been using a Husky compressor for a Trinco sandblaster for years, and always waiting for it to catch up. When buying the blaster, I thought that the 5hp compressor would be enough. NOT It should've been at least a 7 1/2 hp. Even at that, all those compressors are over-rated. The blaster has a 5/16" ceramic nozzle. The compressor tank always seemed to not have any accumulation of moisture lately, so I'd shut the valve and carry on. Just a few weeks ago, I decided to make sure. As nothing came out when I opened the valve, I got down on a creeper, unscrewed the valve to poke a hose removal tool into the hole and eventually, BLAM , all the sh*t came blasting out all over me and some even got on the floor. Damnitall. Proceeded to up-end the whole thing with the A-frame lift and got the large hex fitting out of the bottom. It wasn't hard to get loose as it only had straight threads with a substantial rubber seal. Took a while to get all the remaining crap out of the tank, but I think it's fairly clean now. Chucked up the fitting in the lathe and enlarged the opening from 1/4NPT to 1/2NPT Found some fittings and a valve and assembled them so that the outflow from the valve could be connected to a hose. Now, it's real easy to drain the tank of any water. I do like the auto-drain item mentioned above, might need to go that route if my memory continues in its errant path.
When dealing with compressors you have to open your mind, so to speak. A tool that requires 10cfm, needs 10 cfm constantly to perform. So you go out and buy a compressor rated at 12 cfm-and another spec at a lower air pressure, but yet the tool slows down and becomes less efficient and the compressor turns on. What you see with the rugs the sand blasters use, have no tank or just a small reserve tank, those beast put out 50+ cfm off the compressor. There’s more to a compressor than just HP and CFM ratings, and should be looked at with the intended use.
I wanted to try either one of these, https://www.homedepot.com/p/Maxair-...Vertical-Air-Compressor-C5180V1-MAP/203175530 And a little bigger, https://www.homedepot.com/p/EMAX-80...tor-Pads-and-Auto-Drain-HEI07V080Y1/317326056 If mine goes out I think I'll try one. .
A 1/8th hole will pass around 25 cfm at 100 psi. I'd go for the EMAX-80 if cost is doable. I have a Puma 5hp [big Baldor] like the Maxair but two stage rated at around 20cfm at 90 or 100 psi, at 80 psi it just handles my pot blaster. I don't run the Puma for around the shop I use my old sears 20gallon re fitted with a single stage HF head and small 5hp motor; which puts as much air out as the old 4hp head, at least as far as tank refill time its about 3 seconds less; I think at 100psi its maybe 11 cfm. My Puma is reasonably quiet. Both are plumbed into the air supply so can use either or both.
If I was the OP, I would wait for a good used minimum 5HP cast iron 2-stage with an 80 gal tank. Outfitted properly it will serve the purpose well for a hobbyist shop for blasting/painting or any other air requirements. My current compressor has been in place since 1984. It is as recommended above a cast iron 5hp 2 stage 80 gal with a centrifugal unloader. I took the time to run new copper line from the air compressor. The compressor is outside the garage in an insulated, sound reducing enclosure, on the shaded north side. It's mounted on rubber isolation pads. The tank has a timed self draining valve for removing water. It just drains into a pan. I used a length of rubber through the wall of the garage to eliminate any vibrational effects. I do a lot of sand/abrasive blasting in an outside structure and do all my own painting. When not in use, I do not store air in the tank, therefore it is drained. I achieved zero moisture in two separate airlines. One line has a filter, regulator combo and is water free for air tools, the other is oil and moisture free using a Motor Guard Submicronic Filtration Unit, desiccant water separator, an aft particulate filter and a regulator, specifically for blasting/painting. I used the higher priced 'type L' 3/4" copper which is a lot heavier. There are 4 upright runs with water traps at the bottom. I have not gotten so much as a drop past the second upright. This was built on the bench and then put in place. A lot of soldering that took a few hours to complete but well worth the cost and effort. There is nothing worse than having a spray gun spit out water or clog blasting equipment with moisture. This solved that problem. Works great! I have been a professional painter for more than 50 years and now that I am retired applied what I learned during that time to outfit my home hobby system at a reasonable cost without too much effort. It serves the purpose for my home shop. I use a homemade pressure blaster I made from a 60lb propane tank. I made a gun that uses different size ceramic nozzles and is out fitted with a separate airline for additional air assist delivering the media. In the copper water drop pic below, the compressor is in the enclosure on the other side of the wall. The bathroom fan draws air from the climate controlled garage into the enclosure. The water drops are manually operated. When blasting I have never run out of air, blasting with usually 90 PSI. It builds up enough volume while I am refilling the blaster tank, so I never run out of air. I blast in an outdoor converted gazebo with a pressurized fresh air supplied hood.
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