WARNING: Air Compressor Hazard!!!

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I've got a 7 Hp, 80 gallon Husky vertical air compressor, had it for two years.  The other day, it kicked on an made a strange noise.  When I looked over at it, the belt seemed like it was very loose.  Closer inspection revealed that the frame for the motor had broken and the motor was barely hanging on!I called the manufacturer (Campbell Hausfield) and complained.  They asked if I had it mounted on isolation pads.  No.  They said that if it was bolted firmly to the floor (which it was) the vibration would cause cracks.  They said that even the tank could crack, which would be a serious problem!I looked at the owner's manual, sure enough, it mentions isolation pads and says that they are available separately.  There is nothing stating that they are a required item, or that damage could result if they were not installed.They sold me a new motor at a reasonable cost, but this was not covered by warranty, as it was considered an improper installation.Just thought I'd get the word out.  If you have an air compressor, make sure it's mounted properly!
Reply:Thanks for the info. I was getting ready to buy one just like that except a 60 gallon. I will put mine on a 3/4 inch rubber stall mat from Tractor supply then.Hobart Handler 187Campbell Hausfeld 225amp AC stickwelder. Campbell Hausfeld Versa Arc 95 Mig welder HF 4x6 BandsawHypertherm Powermax 30
Reply:Good information, thanks for sharing!John -  fabricator extraordinaire, car nut!-  bleeding Miller blue! http://www.weldfabzone.com
Reply:You can buy the factory-made isolation pads for $34, + shipping.
Reply:Hockey pucks work fine. I didn't even bolt mine down (60 gal upright, 1 1/2 HP)
Reply:kobalt compressors come with the rubber pads they are about 4x4x 1/2
Reply:You should see our Hammworthy compressors (biggest pieces of junk ever).  70 hp, 535 psi.  They are rubber mounted and move about 1.5 inches in all directions while running.  Sure, the compressor doesn't break but all of the accessories hanging off the sides can't take the vibration and fall off/crack all of the time.  Not that this really contributes, but I thought it was funny.
Reply:Originally Posted by hywyh8rHockey pucks work fine. I didn't even bolt mine down (60 gal upright, 1 1/2 HP)
Reply:76GMC1500, if accessories are actually cracking and falling off your compressors you might consider mounting the accessories to the tank on vibration isolators.  Bonded rubber vibration isolators are incredibly durable (think about what aircraft and automotive engine mounts are subjected to).   By allowing the tank to move independently of the accessories the stress on the mounting pads can be greatly reduced.Two things to beware of are resonances of the vibration isolated items that can allow very large excursions of the isolated equipment and stresses in any tubes or wires bridging the isolators. Excessive resonant amplification of accessory vibration results when the frequency of vibration of the tank/compressor matches the natural resonant frequency of the accessory on its mounts.  Detailed design of the vibration isolation system is possible, but takes a lot of information on mounting configuration, isolator stiffness, mass and moment of inertia of the mounted piece, speed of motor and compressor, etc.  But considering the relatively low cost of isolators, it makes more sense to just use trial and error.  You can start by just selecting the mount that is rated for the load of the accessory, taking into consideration the number of isolators that share the load and any leverage due to eccentric mounting.  In general, any rubber mount should not be deflected by more than about 10 or 15% due to the static load of the isolated item.If the mounted item resonates with the motor or compressor speed, first try clamping some weight to the isolated item.  If that doesn't reduce vibration amplitude you may have to select different mounts.Good luck.awright
Reply:The reason the compressors vibrate so much is they have about a 10 inch diamter LP piston with a 5 inch or so HP piston as the only counterbalance.  All of the accessories are hard mounted to the compressor body, but the bolts eventually loosen or break and that is what causes the accessories to fall off or break.  Some of the stuff, like the intercooler and aftercoolers, we can't do anything about since they are incorporated into the water jacket of the compressor.
Reply:Looked them up on the internet and here is what came up.  This is the same model we use.  The water jacket is blown out from an intercooler failure.  Last edited by 76GMC1500; 05-04-2007 at 06:31 PM.
Reply:Originally Posted by 76GMC1500What part of Canada are you from?
Reply:Originally Posted by cjdavis618Thanks for the info. I was getting ready to buy one just like that except a 60 gallon. I will put mine on a 3/4 inch rubber stall mat from Tractor supply then.
Reply:Originally Posted by hywyh8rHeheh, ahh, sorry. I thought we were talking home shop compessors here  Anyway I'm from Calgary Alberta.
Reply:I like the hockey puck ideal, I have about 20 or so practice pucks, I wont miss three when mounting my compressor.-from Ohio, not Canada.
Reply:Where I purchased mine from said to us the pads or simply leave it on the pallet. If you do bolt it down do not tighten the bolts. Leave them way loose just using them to keep the comp from walking.
Reply:When you achor through the hockey pucks don't tighten them too much, basically just sits on them. I usually use nylon locker nuts that wont vibrate loose. Yeh I'm a Canuk LOL.  Use them on transformers all the time too to cut down on any hum, cheap and tough.Latest Toys Miller 180 Mig and Elite Mask!!Wright Welder 225ACShop OutFitters 20/20 Bending SystemHypertherm 380 Plasma30 Years of Sparking (Electrical & Welding)
Reply:I mounted my 80 gal Ingersoll Rand to an aluminum plate with casters on it so I can roll it around in case I need to move it. I wonder if the casters are enough to protect it. It doesn't move any when running.  I looked in the IR manual and they didn't require isolation pads  I like the hocky puck idea just to be different if anything else.  Michael
Reply:My 80 gallon vertical compressor is sitting on the original wooden pallet that it came with. That probably absorbs a lot of shock, although it runs fairly smooth.I check it all of the time and there's nothing broken yet in close to 12 years.Miller Millermatic 252Miller Syncrowave 200Liincoln AC-DC 225Victor O-A Set
Reply:I'm no hocky player, but my recollection of hocky pucks from long ago was that they are pretty hard.  Hard rubber pucks would not be ideal for isolating an object with low frequency vibration, as from a piston compressor.  But why use an object with completely unknown vibration isolation properties when you can buy proper isolators rated for the specific load of your compressor very cheaply?Check out isolators sold by Grainger (www.grainger.com) like the 3CC17, a 1-5/8" diameter, 1 thick, tapered rubber pad with a 5/8" long 5/16-18 stud projecting up from the bonded top plate.   Probably cheaper than a hocky puck at $2.40 each.  Rated for 80 pounds vertical load, which would allow a 240 pound compressor if the center of gravity was reasonably centered between four feet, meaning the total weight was equally distributed between the feet.While isolator performance is optimum when the isolators are loaded at rated capacity (but not overloaded, which leads to rapid deterioration), you would probably still get better performance than with a hocky puck with much lower than rated loading on a real vibration isolator.You can also consider the sheet waffle-pattern neoprene pads like the Grainger 4C973 (2 each 4" x 4" x 3/8," or 32 sq. in. for $6.91) or the 5C022 (6" x 6" x 3/8," or 36 sq. in. for $7.44).  The material appears to be the same for these two items.  You cut these into pads of the proper area so the weight on each compressor foot loads the cut pad to the optimum of 50 psi, then use a steel plate to distribute the load of the compressor foot over the entire area of your cut pad.  If the weight is different on each end of the compressor you can calculate the area of pad to use that will give you 50 psi (or a little less) on each pad.  Weld a stud on the top of the steel loading plate to keep the compressor from sliding on the plate.  The steel plate will not slip on the rubber pad.Beware of mounting a top-heavy compressor (vertical tank with compressor unit on top) on pads unless you seismically restrain it with slack cables if you are in earthquake country, as I am.  Do not bother with the "neoprene and cork" pads.  Cork is useless in these applications and is offered only because tradition and custom creates demand for them.You can stack two layers of these pads to get better isolation if you put a steel plate between the two pads.  No adhesive required.  The area of the pad remains the same for one or two layers of pad.However, I used my 5 HP big box store vertical tank compressor for years bolted to its shipping pallet with no apparent problems.Have fun.awrightNoise and Vibration ConsultantLast edited by awright; 06-20-2007 at 02:49 AM.
Reply:Originally Posted by awrightI'm no hocky player, but my recollection of hocky pucks from long ago was that they are pretty hard.
Reply:I usually just lag bolt down to 6X6's (southern yellow is good). Decent vibration properties, spread the load out (and widen the base), and raise the ting so the drain is accessible for plumbing. Also easier to sweep the mung out from underneath.
Reply:My Craftsman 7 1/2 hp vertical came with them. I also didn't hard pipe it to the main header, i used a 2' length of hydraulic hose so there would be some flex there...BobBob WrightSalem, Ohio  Birthplace of the Silver & Deming Drillhttp://groups.yahoo.com/group/southbend10k/http://groups.yahoo.com/group/sawking/1999 Miller MM185 w/ Miller 185 Spoolmate spoolgun
Reply:Another workable pad is to go to Harbor Freight and buy a cheap rubber mallet, remove the handle and slice the head into pieces as thick as you want.  I needed some motor mounts for  16 hp leaf vacuum and this arrangement has worked great for 3 years now.  And rubber mallets are much easier to find than hockey pucks in Arkansas.