06 June, 2014

Clearing the air

With the compressed air system fully sealed and holding pressure I am turning my attention to insure the air supplied particularly to spray guns is uncontaminated... The primary filter does a decent job but I wanted to insure dryer air and no oil passing through.

So I have gone ahead, bit the bullet as it were, and coughed up the bucks to get the Desiccant Dryer / Oil Removal Filter unit, and an FRL (Filter / Regulator / Lubricator) connector bracket from Harbor Freight. While they are still in the packaging, I am starting to wonder if Harbor Freight is trying to position themselves up a step or two on the tool quality ladder...

I am going to say this loud and proud, and will probably catch a ton of flack for it, but after my experiences with the wide variety of tools I have used, At this point I would happily cough out funds for HF tools long before I give Black and Decker or Skil a penny... I am noticing the tools I get from HF are higher quality than those better known name brands which has me wondering if Harbor Freight is going to follow by climbing the price tag ladder soon too...

So I started out with the regulator / filter already installed... That needed to be disconnected, bled down and removed from the wall. I have removed the L bracket from the regulator body as well. The FRL bracket I will talk about in a minute gives me great solid mounting options.

Add to that the Desiccant Dryer / Oil Removal Filter that I have on hand...

And the FRL connector bracket... Mind you, I could have just as easily gone with a 3/8" close nipple and connected them together, but I wanted even, consistent mounting brackets across the devices, so I spent the extra $2.00 and got this thing... It will give me a nice clean install and should actually look like the manufacturer intended for all of this to be together...

While I was ready to go, documentation on configuration is kind of lacking, so I needed to make a decision on to mount the dryer / filter before, or after the regulator. I am opting for after so that the flow goes from compressors --> manifold --> regulator / filter --> desiccant dryer / oil removal filter assembly --> output manifold --> hose reel...

The steps I used to install and test were....
  1. Depressurize and bleed off existing system.
  2. Remove the existing regulator / filter from the wall.
  3. Prep wall mount board (already cut to desired size, simply pre drill counter sunk mounting holes and mount to wall).
  4. Remove the nipple and manifold from the outlet side of the regulator.
  5. Thoroughly clean all mating surfaces of outlet including female threads.
  6. Prep the dryer by installing desiccant beads.
  7. Assemble the bracket to the regulator and the dryer / oil removal filter.
  8. Reapply pipe thread compound to the male threads on the nipple / manifold assembly and assemble that into the outlet of the dryer / oil removal filter.
  9. Mount assembly onto mount board and reconnect inlet and outlet hoses.
  10. Pressurize and test for leaks.
I do feel I need to address those that are pooh poohing this rig for lack of lubricant in the air stream. Well that is the whole point! I have for literally decades, used lubricated air tools on pnuematic systems without lubricators, and with filters. You simply need to add some air tool oil to the inlet at the outset of each days work and periodically through the day...

The installation, particularly of the FRL connector was not documented at all and wasn't completely obvious and not everything was machined to fit nicely. Specifically the regulator / filter body niche for the bracket wasn't milled out entirely far enough, and I had to finesse with a fine file. I opted to file a shave off of the ear of the connector bracket though, easier to get to cleanly...

Of course I also addressed swapping out the flaky Husky regulator on my HF 8 gallon compressor. I sourced up a replacement regulator for the HF from HF... Go figure right? Although the gauge ranges higher than the stocker, this regulator appears otherwise identical to the unit the small compressor was outfitted with from the factory. Should be a good clean install. When assembled and pressurized, the gauge still didn't go up to 125 PSI, and shockingly, I had been making a mistake. My small compressor is the 115 PSI not 125 PSI model! No harm no foul on the Husky regulator though, It wouldn't show anything over 100PSI, and the gauge would swing from 80 to 100 all day long... It HAD to go...The Central Pnuematic piece build quality wise is yet another example of HF beating the competition quality and cost wise! 

Once all of these were assembled, pressurized, and adjusted, I ran bubble tests against the joints, addressed any and all leaks, and there were a few, most notably the clear cap for the filter fail indicator on the oil removal filter, and I had to fiddle with the bracket to stop the leaks there, and then ran a leak down test. Keeping them pressurized but off overnight, and both compressors are holding pressure with no drop. Looking good!


I should have posted these earlier, but here is the photo of the completed rig... The regulator / filter has a clean factory assembled look when joined to the dryer / oil removal filter.

In order from left to right, in to out. couplers, check valves, reducer nipples, tee, nipple, regulator / filter, FRL coupler, oil removal filter, FRL coupler, desiccant dryer, nipple, tee, reducer nipples, couplers.  The plastic bulb thing on top where the filter replacement indicator on the oil removal filter is where my leak was when I assembled this. I loosened it up and straightened the O ring, then ran it back in carefully using a 19 MM deep well socket.

The mount board is a simple piece of scrap 3/4" ply screwed directly to the studs, and then the FRL couplers screwed to it using 1-5/8" drywall screws.

And after 26 hours turned off but kept pressurized, the in tank pressure is exactly where it was when I threw the switch to the off position. On the 29 gallon unit mind you, I didn't check the 8 gallon...

Yeah, I am LOVING that picture... 


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