DIY regulator test/flow panel

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So, once you determine that the regulator cracking pressure is off a little, what second stage adjustments are possible assuming you have already adjusted the valve seat to optimum?
If the cracking pressure is too high, then you have not adjusted it to optimum. If that is the best you can get out of it by adjusting, then something else of wrong. Could be a seat, orifice, spring, debris causing the lever to bind, the lever itself, striations on the diaphragm disc, etc.

My understanding concerning a piston-type first stage is that if the IP is low you add shims, too high you remove shims, and if it creeps there is a leak in an o-ring or the valve seat. Anything else?

Wrong, bad, dirty, or double engraved hp soft seat or a defect on the hard seat. Insufficient lubrication of the piston stem and/or piston stem o-ring. The main spring rarely goes bad, but that can happen too.
 
I would like to make a reguletor test panel at home and was wondering if those of you who had done this would share any pictures, parts list, schematics, or other advice.
Thanks

Here are a couple of pictures of my panel. A friend cut the holes out a piece of scrap aluminum for my IP and magnehelic gauges, and another small one for access to a bleed button. Then he bent the bottom to make an L shape so it would stand upright.
reg panel 2.jpg

Just showing off with the next picture. Yes, that is a Balanced Adjustable with a cracking effort under .4 inches of water.
BA cracking under point 4.JPG
 
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I'm going to resurrect this thread rather than cluttering things up with a new one ...

I'm building (at least) 2, toolbox regulator service kits and plan to take the TDI class over the coming winter. To that end, I'm going to need to select Magnehelic and and IP gauges to incorporate.

For IP, I'm assuming any "good-quality" pressure gauge with a 0-200+psi range should be fine.

WRT the Magnehelic, however, I am a bit less sure of what is really needed ... I am aware of the electronic ones, but am leaning toward old-school analog for ease of use.

1) Is a plus/minus type 2-0-2 or 5-0-5 (inH20) really helpful vs. single-sided 0-2, 0-3, 0-5? I'm assuming that since exhale force is really only subject to cleaning and exhaust-diaphragm replacement, Mark I, Mod 0 breath-feel may be good enough and a single-sided gauge may be a better choice, giving greater resolution on the inhale.

2) Is there any benefit to go beyond a range 0-2 (inH20) (or 2-0-2 depending on the above)? I'm assuming that Cracking Pressure will always be set < 2 and that how hard it may be beyond that becomes only a curiosity.
 
I'm going to resurrect this thread rather than cluttering things up with a new one ...

I'm building (at least) 2, toolbox regulator service kits and plan to take the TDI class over the coming winter. To that end, I'm going to need to select Magnehelic and and IP gauges to incorporate.

For IP, I'm assuming any "good-quality" pressure gauge with a 0-200+psi range should be fine.

WRT the Magnehelic, however, I am a bit less sure of what is really needed ... I am aware of the electronic ones, but am leaning toward old-school analog for ease of use.

1) Is a plus/minus type 2-0-2 or 5-0-5 (inH20) really helpful vs. single-sided 0-2, 0-3, 0-5? I'm assuming that since exhale force is really only subject to cleaning and exhaust-diaphragm replacement, Mark I, Mod 0 breath-feel may be good enough and a single-sided gauge may be a better choice, giving greater resolution on the inhale.

2) Is there any benefit to go beyond a range 0-2 (inH20) (or 2-0-2 depending on the above)? I'm assuming that Cracking Pressure will always be set < 2 and that how hard it may be beyond that becomes only a curiosity.

While you are correct that most of your interest will be around 1-1.5" of cracking effort, most regs with adjustable cracking effort knobs add 1.5" or more to the set cracking effort. In order to properly adjust all these regs, you really need to be able to see out to 3".

And while it's nice to view expiratory effort, the tighter scale of a -5"-0-5" gauge (I haven't seen a 3-0-3 gauge, though I'm sure they must exist) makes setting your key cracking effort at 1.1" more difficult to identify.

If you can only have one gauge, 0-3" is my favorite.
 
Don't know if you are aware of this but on mags, you don't have to have a x-0-x model to measure both. You can measure both pressure and vacuum by changing the positions of the hoses- or at least the ones I have you can, you can't do both at once but you do have the capability to measure either one with any mag . Obviously more of a pain since you must move hoses but it's still available.
 
While you are correct that most of your interest will be around 1-1.5" of cracking effort, most regs with adjustable cracking effort knobs add 1.5" or more to the set cracking effort. In order to properly adjust all these regs, you really need to be able to see out to 3".

And while it's nice to view expiratory effort, the tighter scale of a -5"-0-5" gauge (I haven't seen a 3-0-3 gauge, though I'm sure they must exist) makes setting your key cracking effort at 1.1" more difficult to identify.

If you can only have one gauge, 0-3" is my favorite.
:(
After 2 weeks of nuthin here, I bit the bullet and ordered a couple of 0-2" Mags off eBay for about $43 ea. Since my LDS uses a 2-0-2 in the bench panel, I figured it would be good. I had not thought about testing them while cranked down. I'll try tuning them wide-open and if it truly becomes an issue, I'll just have to swap them out.

Don't know if you are aware of this but on mags, you don't have to have a x-0-x model to measure both. You can measure both pressure and vacuum by changing the positions of the hoses- or at least the ones I have you can, you can't do both at once but you do have the capability to measure either one with any mag . Obviously more of a pain since you must move hoses but it's still available.
I was aware of it, but didn't think about bringing both ports out for connection. I'll try to do it.

Thanks, guys!
 
This is my IP manometer, 11 euros well spent on Amazon:
https://www.amazon.it/STANLEY-Misuratore-Pressione-Gomme-Semiprofessionale/dp/B07VSVX49V
71GQL6BSXgL._AC_SX466_.jpg

It shows both PSI (whatever they mean) and bars.
Of course I had to cut the hose and install the proper termination for being screwed into an IP port of first stage.
Regarding cracking and exhale pressures, I am fine with the U-shaped transparent pipe filled with water.
I often evaluated to go electronic, and to buy a differential digital transducer, to be connected with my laptop for recording the whole time history of instantaneous pressures along a whole respiratory cycle. But those transducers are expensive, and I need to use it perhaps once or two per year, so it is not worth the expense.
 
Since we're all sharing, here's the traveling tuning kit my son made (with a little input) prior to heading off to IDC. It all fits in a Husky tool box, and he carried nipples out to one side to attach to the first stage on 300psi and 3000psi tanks for tuning. In the lower left corner, he's built in a little precision test pump to measure cracking effort, a la Regulator test rig you don't need to suck.
In the center is a hardware store regulator that ends in a scuba hose thread to attach second stages, that is adjustable to any desired IP, in case someone just hands him a second stage to repair or tune. He uses an old Conshelf XII overtuned to 160psi to supply the adjustable regulator from a nipple on the lower left edge of the case, and can thus tune a second to any desired IP.
He spent days sanding and varnishing the inset panels that make his work surface. I have to admit, it's compact! Wish I had that much leisure time! I guess there are a few benefits to the COVID lockdown. The lucky guy just finished two weeks and 57 day and night boat dives in Key Largo! We had some long talks about ascent profiles since he was packing in that much diving. He paid for 2 weeks of unlimited boat dives. I guess he got his money's worth!
IDC starts next week.
IMG_5108.jpg
 
https://www.shearwater.com/products/swift/

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