Magnehelic techniques?
Posted: Mon Jun 05, 2017 5:22 am
Spurred on by my modest success in restoring my USD Aquarius and the Scubapro 108 I've been thinking about getting a Magnehelic!
I have four Atomic Aquatics regs with octos that need maintaining, so been working my way toward that goal...
I know I can do a rough check in a basin of water, but I'd like to see actual data for each reg I'm rebuilding... and have a known point to return to if needed after each service.
From what I can determine Dwyer have the market pretty much sewn up, and the Model 2304 (Differential pressure gauge, range 2"-0-2" wc minor divisions .10) seems most suited to SCUBA use.
So far so good...
However, I'm having a bit of trouble working out the correct way of attaching the Magnehelic to the regulator... I've seen a couple of what looked like commercial accessories involving a mouthpiece mounted to an oval tube with a serrated spigot, but can't seem to locate one to buy online. Also several home made versions which just seem to be cobbled together with whatever spare bits were lying around the workshop
Is the attachment point of the test gauge intake spigot in relation to the mouthpiece critical to prevent excessive fluctuations in reading or not really a worry?
When taking readings what is the best procedure?
Let the LP seat bed in for a certain amount of time to stabilise before checking?
A series of checks then average them?
Take a soft gentle intake of breath for a double hose and a sharper one for singles to mimic their usual operation?
When exhaling I assume the 2"-0-2" gauge can just be left connected, but a 0-2" gauge would need to be reversed to read pressure instead of vacuum?
Be great to see one of Bryan's videos concentrate on using a Magnehelic properly, and what it can uncover as a diagnostic tool... but in the meantime I'd be very grateful for some pointers
I have four Atomic Aquatics regs with octos that need maintaining, so been working my way toward that goal...
I know I can do a rough check in a basin of water, but I'd like to see actual data for each reg I'm rebuilding... and have a known point to return to if needed after each service.
From what I can determine Dwyer have the market pretty much sewn up, and the Model 2304 (Differential pressure gauge, range 2"-0-2" wc minor divisions .10) seems most suited to SCUBA use.
So far so good...
However, I'm having a bit of trouble working out the correct way of attaching the Magnehelic to the regulator... I've seen a couple of what looked like commercial accessories involving a mouthpiece mounted to an oval tube with a serrated spigot, but can't seem to locate one to buy online. Also several home made versions which just seem to be cobbled together with whatever spare bits were lying around the workshop
Is the attachment point of the test gauge intake spigot in relation to the mouthpiece critical to prevent excessive fluctuations in reading or not really a worry?
When taking readings what is the best procedure?
Let the LP seat bed in for a certain amount of time to stabilise before checking?
A series of checks then average them?
Take a soft gentle intake of breath for a double hose and a sharper one for singles to mimic their usual operation?
When exhaling I assume the 2"-0-2" gauge can just be left connected, but a 0-2" gauge would need to be reversed to read pressure instead of vacuum?
Be great to see one of Bryan's videos concentrate on using a Magnehelic properly, and what it can uncover as a diagnostic tool... but in the meantime I'd be very grateful for some pointers