Re: Unplanned Upgrade

On 7/7/2025 3:35 PM, Bob La Londe wrote:

Yesterday I was using an air drill on the work bench on my CNC machine room.  I stage blanks on that bench and do some minor secondary work there.  Mostly de-burring the backside of thru holes.  I keep an air drill with a ball valve for speed control at that bench with a counter sink tool for deburring and adding a slight chamfer to the back side of holes.
 When I picked up the drill it sounded funny and didn't run right.  I turned up the air flow and water came out of the vents.
 OH SHIT!
 I bled the valve on the wall manifold where the drill was connected and water came out.  Not a lot, but not a little.  Then I walked up stream to the next down drop, that feeds a machine, and quite a bit more came out of that one.  The FRL was also bubbling out the top of the oiler. There was also a fair amount of water in the separator.  Fortunately I have not used that machine in over a week (maybe two), so its not likely any water got into the air cylinder on it that activates the tool release.  It was the only on machine separator that had water in it, but almost every air manifold on every down pipe drained water when I opened the ball valve I installed on every one of them.
 I think I was right on the edge of catastrophe.
 When I checked the compressor and dryer there was a bit of water in the air tank.  It might have been more than normal, but not much.  The separator upstream of my air dryer had some water, but again it seemed like a normal amount or only a little more at most.  I drain both of those every day I am in the shop.  Sometimes twice.
 Then I checked the manual drain on the air dryer, and it also seemed about normal or just a little wetter than normal.  Finally I checked the safety check separator.  The one directly down stream of the air dryer. It was WET.  By that point I wasn't surprised, but it confirmed the air dryer either wasn't working or wasn't keeping up.  Usually if I am running every machine, and doing some manual air usage I'll get some water past the air dryer on a humid day, but humidity was only 15% yesterday according to online weather sources.  I wasn't running a lot of machines or using a lot of secondary air.  It felt hot outside at 110F, but not that humid sweltering hot when the humidity climbs.
 I'd already shut everything down, and was just testing off tank pressure.  My air dryer is an older style Harbor Freight unit, and its good for maybe 20-25 CFM at 100 PSI.  I've been running it over pressure, and if I use an air blast on one of the machines it will get overwhelmed pretty quickly.  All of my redundant separators and dryers along with a 7 vertical up to feed are usually enough to protect my machines.  Yesterday is the first time I ever had any water in a separator on a machine.  Fortunately just the first one on the line it looks like.
 Of course I drained all the drop tube drains, and disconnected that one machine from the air system.  If I have to use that machine I can use a wrench, but I'd rather not.
 Now I was confident as longs the compressor on the dryer isn't burned out I can repair the dryer.  I might be able to repair it even if it is, although its not as serviceable as something like a split system.  I also have a spare, brand new, still in the box air dryer on the shelf. Never opened.  In fact many years ago when I bought it from a closeout company there was a mix up and they wound up sending my four of them.  I offered to let them pay freight to return, and they offered me a huge discount on the extra units to just keep them.  I sold off two, and kept one as a spare.
 I was steeling myself to swapping them out, but instead I walked in the office, sat down at my desk, found a unit capable of drying 75CFM and handles much higher pressure, and ordered it.
 Not wanting to sit idle for several days I considered my options.  I decided the first thing to do was check out the unit currently installed.  I pulled the covers with it powered up.  I don't recall noticing an error light (dumb idiot light only) on the front, and the rests inside were not tripped.  The fan was running, but the compressor was not, and it was so hot it was painful to touch.  Then I looked at the other side and saw the condensing coil was covered in a layer of lint.  I blew the lint off, hit the fins with some cleaner and compressed air, and turned the unit on again.  The compressor pump started up.  I shut it down and called it a night.
  Now I am about to walk back out there and power up the air dryer again. If it works I'll run a light load for the next few days until the newer bigger dryer arrives.  I'm actually ahead of schedule on customer jobs except for one I need to redesign so I might take a few days off rather than swap in the spare if it doesn't work.  I picked up a new Insta360 X5 sport/action camera, so I might go out and shoot some fishing video to promote some of my mold designs.
 Oh, yeah.  I also ordered a brand new FRL from McMaster for that one with water in it that was leaking out the top of the oiler.  I could probably fix it, but I probably won't.  It was a cheap FRL anyway.  I'll probably just save the filter regulator, and toss the lubricator.
 Be back in a minute.......
 Okay, all I think I feel putting my hand on the compressor in the dryer is heat building up, and the vibration from the fan.  I seem to recall I could feel the pump a little more aggressively doing its thing than that.  I also didn't feel any temperature differential in the refrigerant lines.  Depending on the refrigerant (modern ones like 410 or its replacement) you may not get the super hot  and super cold like you did on the older stuff, but its still easy to tell by feel.   I think I have a compressor burnout.  I learned to service refrigeration when I was just barely a teen, so I am sure I could source a compressor and repair it, but I don't think its worth it.  Probably save the fan motor and cap and take the rest to recycler.  (Legal disposal of refrigerant is a pain).
 I left it running while I came into to type up that last paragraph.  One last check (yes the air compressor is on and the shut off valve is open) now that its been powered up for a few moments to see if its working and...
 Nope!  Still no temperature differential on the refrigerant lines.  Its coming out.  I can't complain.  After the deal I got on the extra units, and being to sell them off at a substantial profit it was almost free, and its outlasted the original air compressor it was connected to and a few years into the second one.
 Its coming out.  I don't know if I'll swap in my spare or not.  I guess it will depend on how much my OCD pushes me to get jobs done verse going fishing and doing design work.
 FYI:  I think Harbor Freight discontinued these, because they were unavailable after I bought mine from a third party (shipped from Harbor Freight).  Harbor freight has them again, but I bet its a newer revised model.  I had to service this one a few times.  Little things, but things many people might have struggled with or not been able to take care of.  The new one is about twice the price I paid, but after all these years that's no big surprise.

I really should have installed a larger air dryer years ago anyway.  I am sure I've been right on the edge of catastrophe many times.
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Bob La Londe
CNC Molds N Stuff
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