Air Compressor Woes - Its Not the Bandaid - Pressure Switch

A while back the check valve on my main air compressor died. I took it out, took it apart, cleaned it up, and threw an o-ring in it as a
temporary seal and repair. Its worked great. On Friday I noticed a slow leak after I shut everything down. The sound was coming from the pressure switch and unloader valve assembly. I ordered a new pressure switch to be delivered today and forgot about. Yesterday I was in Nogales picking up a load of steel plate anyway, so today was fine.
Oh, yeah. Side brag. I'm sure you guys all get it cheaper, but one piece of 4x8x1/4 plate from the local Remington Industrial was $240 give or take. I found some in Nogales for 135 for the first piece and $100 for every additional piece. I don't need that much right now, but I bought ten pieces to make it worth the trip. If I have it I'll use it.
Back on topic. As I was walking out to the compressor it occurred to me that my o-ring band-aid might have failed and I had ordered in a pressure switch assembly for nothing. So with pressure still hissing out of the pressure switch I unplugged the hose from the top of the check valve that goes to the unloader and checked the fitting with my thumb. No air leaking and the hissing from the pressure switch was just as loud. In fact much louder than on Friday.
Now an odd question. Probably a dumb one at that. What is an air compressor pressure switch with 4 ports intended for? When I was shopping for one I saw single port and 4 port models. Both were under $20 in generic brands and not much more for name brands.
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On 8/14/2018 12:51 PM, Bob La Londe wrote:


Ok, doh! Yeah, that was a stupid question. LOL. A single port is pretty much an exercise in additional expense since there's no place for a gage or pop off valve. LOL.
Glad I ordered a 4 port.
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wrote:


Damn!, now I have to put shoes on and go down and look how I rigged up my 2CFM Gardner/Denver I paid $3.00 for ten plus years ago. Neighbour couldn't imagine why anyone would want an air compressor untill the tubless tires on his snow blower started leaking.
Ah-hah!a real plumbers nightmare of used fittings, nipples and a four port manifold - some day I will take it apart and re-do it; but then again, it ain't broke.
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"Gerry" wrote in message wrote:

Damn!, now I have to put shoes on and go down and look how I rigged up my 2CFM Gardner/Denver I paid $3.00 for ten plus years ago. Neighbour couldn't imagine why anyone would want an air compressor untill the tubless tires on his snow blower started leaking.
Ah-hah!a real plumbers nightmare of used fittings, nipples and a four port manifold - some day I will take it apart and re-do it; but then again, it ain't broke.
**********
Ha! LOL. I know about plumbing nightmares. Try getting what you need from Home Depot to do an emergency repair on the weekend. The will gladly sell you nine over priced fittings to do the job of one reasonably priced fitting you could buy elsewhere. A lot of times I get frustrated and just make what I need out of aluminum or brass.
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I've collected pretty much at least one of each common fitting, the smaller ones in brass and the larger in black iron. When I use one I put it on the shopping list to replace. Many are marked with their nominal size to help identifying threads.
The machined brass ones generally run true enough in the lathe to hold other pipe or fittings for modifying, using either light cuts or the support of a tailstock pipe center. The narrow hex doesn't provide much support, even in a 6-jaw.
A large enough True Value hardware store may carry a significantly better selection than HD.
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"Jim Wilkins" wrote in message

I've collected pretty much at least one of each common fitting, the smaller ones in brass and the larger in black iron. When I use one I put it on the shopping list to replace. Many are marked with their nominal size to help identifying threads.
The machined brass ones generally run true enough in the lathe to hold other pipe or fittings for modifying, using either light cuts or the support of a tailstock pipe center. The narrow hex doesn't provide much support, even in a 6-jaw.
A large enough True Value hardware store may carry a significantly better selection than HD. ***************
A tiny little country True Value store may have a better selection than Home Depot. We had a True Value (my dad) called BJ-Supply Co when I was growing up. Right next door to our grocery and general store. El Camino Market. You could buy jeans, shirts, a washing machine, most any pluming fitting, and a new starter for your truck without moving your vehicle. When I moved into town it used to drive me bonkers having to drive all over town to get six parts for a job and have to check nine stores to get them, when I knew we had all of them on the shelf at the hardware store back home. Those stores are closed now, but they served the community for several decades.
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On Wed, 15 Aug 2018 12:56:57 -0400, "Jim Wilkins"

Ditto. When I need one, I get 3, trying to keep stock of anything I might ever need. It's much cheaper to have one in stock than to have to try to find one at midnight on a weekend.

There's something new to me. Tailstock pipe center. Is it simply a larger live center?

HF has lots of small brass in many shapes, so I stocked up during a recent sale. The local Grover Plumbing & Electric has the best pricing and selection, so I stocked up on 3/8 and 1/4, finding some 1/8", too.
Hardware at Ace is usually quite pricy, but they have a large stock. It's nothing like an old-style =real= hardware store, though. I miss those!
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wrote:

They are also called Bull Nose centers: https://www.ebay.com/bhp/bull-nose-center
I also have a center with a concave cone center that's useful to align the right-hand end of bolts while closing the chuck on the hex flats. Then I drill the end for the pointed live center.
There's also a "half center" which gives clearance for cutting around the end of the work. https://www.ebay.com/sch/i.html?_from=R40&_trksid=m570.l1313&_nkw=lathe+half+center&_sacat=0 I used one a few days ago to turn down a 5/16" bolt into a 7mm pivot pin with 1/4-20 locknut thread for a limb cutter blade. The original pivot pin nut wouldn't stay snug.
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I got it all back together yesterday, and while I had it apart and the tank at one atmosphere I added a single quick coupler in front of the shut off valve to the rest of the shop. Now I don't have to go through a full start up and shut down to air up a tire, and if I need to blow out the filter screen in one of the separators or the air dryer I can without getting the roll around out of the garage.
Seemed to take forever to come up to pressure, but I stood there patiently and slowly adjusted down the pressure shut off screw as it approached my desired shutoff pressure. Nailed it about perfectly first try. Then I popped the safety valve and it kicked back on about 10PSI above the highest minimum pressure I need for any automated or semi automated equipment.
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"Gunner Asch" wrote in message wrote:

Excellent! Smart move.
Part of my job is installing and maintaining air compressors of every brand and type.
Far too many of them have a min pressure of 150 with a max shut off of 175 or so. This is fine when you have a single tank..but most of my clients run auxillary tanks around the shop so they have on average.. 500 gallons of air just sitting around. Takes forever to pump that much volume up to 175 and then using it at max of 100 pounds..most units require 80-90 lbs. Run em at 125 at most..takes a big load off the compressor(s) and runs the system well enough for nearly all applications. One of the reasons I like screw compressors...let em run full time so you dont have start/stop surges, and when they drop down to the minimum..they kick in the clutch and fill the system back to full (generally 125) in just a minute or two.
Gunner __
*************************************************************
I've been considering an aux tank in my little machine room with a one way check valve. This way I can keep the machines with air seals running for a long time if I have to do some air line service elsewhere. The machine with an ATC requires more air pressure, but I have not been getting as much use out of that machine as I thought I would. Oh, I use it, but mostly for secondary stuff. Still a couple tool changes will go a long way towards finishing a job, and the machine will just stop at the tool change if the air drops to low. On the other hand both times I've had an airline blow out its been inside the machine room. I've also been considering replacing the gas springs with air cylinders and a reserve tank at each of the little machines.
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On Thu, 16 Aug 2018 10:54:50 -0400, "Jim Wilkins"

Wild. Those half centers are shaped similar to hole-type countersink/deburring bits. This answered some questions.
https://www.youtube.com/watch?v=-pImQr0qBQ4

Now that we have that out of the way, has anyone here made any Sandia alloy yet? https://share-ng.sandia.gov/news/resources/news_releases/resistant_alloy/
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wrote:

Seein' as I have no lathe, I'm afraid not.
--
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