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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Len Silva on December 04, 2009, 07:32:01 AM

Title: Dryer for shop air
Post by: Len Silva on December 04, 2009, 07:32:01 AM
In my shop I need dry air for sandblasting glass.  Commercial refrigerated or desiccant dryers are quite expensive.
I was thinking of using a truck dryer and wonder if anyone here has tried it.  I can get a dryer from a junkyard and rebuild it for much less than a commercial unit.

I imagine those of you who do painting must have similar moisture problems.

I could come up with a way to make it cycle properly.

Comments?

Len
Title: Re: Dryer for shop air
Post by: TomC on December 04, 2009, 07:35:09 AM
Should work, then I would also have a double tank-like you do on the bus-a wet tank, then the tank you tap into.  Good Luck, TomC
Title: Re: Dryer for shop air
Post by: Dreamscape on December 04, 2009, 10:45:08 AM
Might work, don't forget to put a down line about 12" below the T with a ball valve to drain off excess, that will catch a lot of moisture. The farther from the compresser the better too. Then put a trap before your machine to catch anything before it enters your tool.

Paul
Title: Re: Dryer for shop air
Post by: luvrbus on December 04, 2009, 11:37:35 AM
Len, I use the throw away desiccant type for my plasma cutter cost about 8 bucks each buying 12 to a case from a welding supply the CFM maybe a problem for you they are rated at 20 CFM they last about 2 weeks when using a lot. 


good luck
Title: Re: Dryer for shop air
Post by: Hobie on December 04, 2009, 11:40:34 AM
Most centrifugal air dryers (even the cheap ones) will work quite well but often get blamed for not stopping all the moisture.  The reason is they need  cool air to work correctly.  This is why the dryest air is the furthest from the compressor.  The distance cools the air.

Here is a fast trick.  Get a 5 gallon bucket and fill it 3/4 with cold water.  Then make a coil of copper tubing with air fittings on both ends and simply drop the coil into the bucket.  Then attached the dryer to the outlet and on to your working airline.   The water cools the air and you will be amazed how much better your dryer works.  After a couple of hours the water starts to warm up so just dump it and refill.   Guess you could throw in some ice but I haven't found it necessary.  

I made mine using a 10 length of copper 1/2" tubing from Home Depot.  It is packaged in a box and is coiled.   I brazed male air fittings on both ends and made an adapter hose to use quick couplers to connect everything.  

For sandblasting this will do the trick.  For painting and you want the best I add a particulate filter ( looks like a roll of toliet paper inside) and a dissicant ( color changing granules)  filter to this set up and you will have 100% clean, dry air.  
Title: Re: Dryer for shop air
Post by: Len Silva on December 04, 2009, 01:22:28 PM
Thanks guys,

A already use the coil in the bucket trick, including ice.  Just trying to streamline things a bit. I'm not having any problems this time of year, but the 95% humidity in the Florida summers is a pain. About every two weeks, I have to dump all my abrasive (about 100 lbs. and dry it in the oven.  My wife doesn't like that. :)  I am going to look into the desiccant from a welding supply, can you give me any more info on what to ask for? Or a link? I am typically well under 10 cfm.

I call it sandblasting, but it's actually aluminum oxide in 200 grit.  It tends to clump up in the pot if there is any moisture.  That causes sputtering and spitting which is a problem.  Some of what I do is much like airbrushing, except that I am using abrasive.

Len
Title: Re: Dryer for shop air
Post by: compedgemarine on December 04, 2009, 03:36:50 PM
the dryer we had on our shop air system had three stages. the first two were basically water traps and the third was about three feet tall and eight inches across and had the disacant in it. it did specify that it had to be install a minimum of 50 feet away from the compressor. never had a water issue after installing it.
steve