Intermediate Pressure Gauge

[Zung]

I've got 3 and they are fairly consistent: left, CL 2.5: $30 @ dive shop, center, CL 1: $2 @ eBay, right, unspecified: $10 @ hardware store. CL is the nominal precision.

The big one is slow, possibly because it's filled with liquid, or maybe because of the bigger Bourdon tube inside. Its response time is actually slower than the time it takes a decent 1st stage to recover after a purge, so it may hide some problems.

 

[keyshunter]

The Scubatools gauge developed a 15 psi error after a couple years and had to be replaced.

Interestingly, my Scubatools IP gauge, which is about 10 years old has an error of 15 PSI on the high side (reads too high). It has been quite consistent, but I take it to an LDS occasionally and check it against their gauges.

 

[macado]

This is actually a very easy DIY project to make yourself. I've made a couple from parts from Harbor Freight and NPT adapter from Northeast Scuba or Piranha. In the end though, you're not really saving much money and can buy one from Piranha cheaper. I put an over pressure valve on mine but you could just as easily leave a second stage attached to prevent over pressure.

BC fitting for NPT 1/4 (3.99) NPT Fitting 1/4M Thread "MA-04"
Brass T connector (2.50) Harbor Freight
300 PSI Dry Gauge (5.99) Harbor Freight

 

[Bigd2722]

I have this one, that I paid $65 for.
A.I.R. Flow Analyzer, Four SpinOns, & Floating Wall Bracket Assy[/QUOTE]

How much did you pay? I see $875.00 on the web site

 

[DA Aquamaster]

This is actually a very easy DIY project to make yourself. I've made a couple from parts from Harbor Freight and NPT adapter from Northeast Scuba or Piranha. In the end though, you're not really saving much money and can buy one from Piranha cheaper. I put an over pressure valve on mine but you could just as easily leave a second stage attached to prevent over pressure.

BC fitting for NPT 1/4 (3.99) NPT Fitting 1/4M Thread "MA-04"
Brass T connector (2.50) Harbor Freight
300 PSI Dry Gauge (5.99) Harbor Freight

My first one was an air pressure gauge and 2" 1/4 NPT nipple from the hardware store and a 1/4 NPT to QD adapter from the dive shop and was in the $20 range.

 

[Peter_C]

How much did you pay? I see $875.00 on the web site

I paid $65 for it used. That was only one of many good deals that day. Even still it was an expensive day.

Paid $35 for one of these.
Scuba Compressor

$400 for a set of these with the regulator and two fill whips.
Scuba Compressor
Scuba Compressor

I was broke by the time I left. There is a lot more though than what I just listed.

 

[HenrikBP]

Interestingly, my Scubatools IP gauge, which is about 10 years old has an error of 15 PSI on the high side (reads too high). It has been quite consistent, but I take it to an LDS occasionally and check it against their gauges.

Buordon tube gauges are kinda sensitive. I used them for tire pressure checking on my motorcycles, but kept in mind a test I saw where a single drop/bump would put the gauge out of spec. I just recently dropped m "field" IP gauge, and it now reads 20 psi high. But since I know it's off and about how much it doesn't really matter

 

[Nemrod]

I made the IP gauge I use the most from an old LP hose. I cut the BC QR off, installed a 1/4 barb (I think that is the size) to 1/8 NPT female and a stainless hose clamp. My oil filled gauge screws into the male NPT. If I suspect the gauge is not accurate I take it to work and calibrate it against certified gauges. If adjustment is needed I do it. It is only important that the gauge be accurate, relatively speaking, within the working range which is 90 to about 160 psi.

Two of my Magnahelics I bought at a local, famous, surplus house, the other two came from ebay. I made my own flow meter from a hang glider airspeed indicator but I need to make something better, maybe.

N

 

[HenrikBP]

If I suspect the gauge is not accurate I take it to work and calibrate it against certified gauges. If adjustment is needed I do it.

Hi Nemrod,

To adjust IP gauges, do you simply take off the face and bend the Bourdon tube as necessary? Or I guess maybe you can just move the needle back to "0"?

 

[Nemrod]

Hi Nemrod,

To adjust IP gauges, do you simply take off the face and bend the Bourdon tube as necessary? Or I guess maybe you can just move the needle back to "0"?

No, my gauge has an adjustment screw. However, on cheaper gauges I would just slip the pointer.

Who cares about zero, I care about the working range accuracy. I set my gauge to a calibrated source or gauge at the middle of my range of interest which as I said before was 90 to about 160 psi so I set my gauge to read true at around 120 psi. If it is off at zero, I do not care because I am not trying to set zero IP, I am trying to set IP around 120 to 140 psi.

Absolute accuracy is not required for this stuff, if you are setting all of your first and second stages in a fleet of regs to all work together, be compatible, then as long as you are using the same gauge on all of them you ought to be OK.

N