Compressor Hook-Up

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I have used the search procedure and read everything I could on sand blasting and air compressors. I appologize if this is a duplicate question but I am not sure what to do. I bought one of those Tractor Supply sand blasters (the pressure type), started with a 5 hp compressor and it isn't able to provide enough air. Obtain another 5 hp compressor and would like to know if I can somehow hook the two up together. Will I need a third tank and feed both of the compressors into the third and feed the outlet to the sandblaster? If money was no object I would buy or rent a larger unit but I am about broke and hopefully I can come up with a "economical" solution. I am trying to remove the paint from a covered stock trailer and I hope I haven't bit of too much. Would like to say look what I did but if things keep bogging up on me may have to "farm" this one out. Any suggestions would be appreciated.
Reply:Yes you can run both together to increase your volume. An extra tank would be nice but not required. Just install a T to link the 2 machines output. The big thing will be is the supply hose a large enough diamiter to supply the required amount of air? 1/4" is way too small. 3/8" hose is posibly borderline.When ever we use a big pot type sand blaster we break out the big IR 185 Jack hammer compressor and the 3/4" hose for the jack hammers. I hate to tell you this, but they rent for a whole lot less than a 2nd 5HP compressor. You can run one of these machines nonstop all day long and always have more than enough air. We seldom need more than one day to do the big dumptruck, 15 ton tag along trailer, and whatever else we can find to blast, plows machines etc. Often the biggest problem is keeping the blaster filled.
Reply:First of all, you don't generally need full pressure to operate a sand blaster; you need a high volume at maybe 50 psi. Too high a pressure can actually increase the warping of thinner sheet metal by 'peening' the metal.Secondly, you can use a smaller jet and nozzle if you don't have enough air to power the satisfy the sizes you're using right now.Thirdly, you need to remember to follow the correct duty cycle for the compressor, even if you get one which supplies the amount of air your blaster needs. That said, yes you can hook up two compressors, just using a "T" between them to run their output into one hose. If each has its own tank, a third tank isn't necessary but might be helpful.Remember that you need to have adequate power going to each motor; you need both voltage and current.BTW, not all HP ratings are the same; a true 5hp motor with an efficient pump should be able to put out at least 10cfm at 90 psi, and a two stage pump might reach 18cfm at 175 psi.
Reply:Thanks for the quick replies; I don't want to sound like a d/a but here goes; I don't know a dang thang about cfm's. The sand blaster says 6 - 25 cfm with working pressure of 60-125 psi. The gauges on the air compressor I know are in psi and I "assume" the gauge on the sand blaster is psi. When using the sand blaster at about 65 psi and above, I get good removal of the paint..and that is using just one compressor. However it doesnt take long to "run out of air".  I checked on renting a compressor..two different places..$1000 holding fee then daily rent..not for me. So, going by info provided, yes I have enough electrical power, can increase hose size, but have no ideal how to tell what cfm is being used. One of my tanks I have a T coming out, so I can just connect the ouput of the second into that with no problem. So I guess the biggest problem I have is how do I know what cfm I am using or with the dual hookup just adjust the sand blaster to where it is doing a good job of removing the paint and not worry about the cfm's other than trying to educated myself on cfm's. Thanks again..jr
Reply:CFM is a measure of the volume of air the compressor puts out. The simplest way to get an idea on this is to read what the manufacturer rates the machine at. Usually they will list something like 5 cfm@90 psi and then 3.5 cfm @ 120psi. What you are measuring is how fast the compressor can catch up to the air used at a certain psi. You can extend the use if you have a larger reserve tank and start with it at max psi. The tank will take longer to run down, but then take longer to rebuild pressure as it has a larger space to refill.The rental sounds wrong from what you listed. I was talking about a diesel or gas tow behind screw machine used to run jackhammers. I can walk into almost any contractors equipment rental with my drivers license and credit card and walk out with the machine and just pay the 1/2 day or daily rental of say $65-$110 plus the damage waiver if I choose to take it. Were you looking at an electric compressor? That I might understand as they would usually rent for extended lengths of time to a commercial shop.On these machines the model usually is an indicator of CFMs at say 90 psi. Out IR 185 puts out 185 cfm at 90 psi continuous, more if you run a tool at a lower psi with a regulator.