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D420! How about that?
- Thread starter axxel57
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I try to tap a diaphragm against the lever after adjustment. I think there should be about 1/2mm separation. If the hex is too tight it will lift the lever right against the diaphragm, so that when you screw the faceplate back on, the poppet wants to lift due to elasticity of the diaphragm.
I was surprised by how floppy I thought the lever was, and was initially concerned I wouldn't get enough poppet lift. But I was wrong. Instead, I had the same trouble you did.
I haven't tried a rattle test, but you can imagine what 1/2mm might do. It would be pretty subtle. But the point is that there has to be SOME separation before you screw down the faceplate.
I was surprised by how floppy I thought the lever was, and was initially concerned I wouldn't get enough poppet lift. But I was wrong. Instead, I had the same trouble you did.
I haven't tried a rattle test, but you can imagine what 1/2mm might do. It would be pretty subtle. But the point is that there has to be SOME separation before you screw down the faceplate.
- Messages
- 17,658
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- Messages
- 17,658
- Reaction score
- 9,909
- Location
- Somewhere between here and there
- # of dives
- 2500 - 4999
Forgot to mention, bubble dispersion I found to be pretty average, actually reminded me of my old Micra. G250 does a better job.
Apeks XTX with wide exhaust and Conshelf both leave the D in the dust when it comes to bubbles across mask.
Apeks XTX with wide exhaust and Conshelf both leave the D in the dust when it comes to bubbles across mask.
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I may have worded it wrong, I mean I was setting cracking with Venturi in both positions. With Venturi on min which of course resulted in a much lower cracking with Venturi on max, as I wasn't paying attention this explained why I was initially getting erratic readings and leaks.
The Venturi lever moves the hex, works same as an adjustment knob I guess.
Hang on, is it called Venturi on the D?
The more I read this thread, the more I am convinced to stay with "old school" 109-BA, or 156, or G250...
The description given by Simon sounds similar to my own impressions when I was given a first-gen Pilot to test (and possibly to purchase) back in 1978 (or perhaps 1979). After using it a couple of times, I returned it promptly...
It was very easy to breath and to exhale, but it was very "nervous", sometimes freeflowing, and it exhausted my twin cylinders in half the time I was used to get with my MK5-109....
The description given by Simon sounds similar to my own impressions when I was given a first-gen Pilot to test (and possibly to purchase) back in 1978 (or perhaps 1979). After using it a couple of times, I returned it promptly...
It was very easy to breath and to exhale, but it was very "nervous", sometimes freeflowing, and it exhausted my twin cylinders in half the time I was used to get with my MK5-109....
It's really quite ingenious, @couv !
Not only does the Venturi lever change the vane inside the mouthpiece to add turbulence and decrease Venturi flow in the Pre-Dive position, it also rotates the hex screw about 1/8 turn. Since the entire range of the adjustment screw for reasonable cracking efforts is about three quarters of a turn, what is happening is that as you increase the turbulence to reduce the chance of freeflow, you are also slightly increasing the cracking effort. All in one!
Now the increase is small (about 0.1 inch) but it's not insignificant. Really quite ingenious.
I really have to disagree with @Angelo Farina . Remember, Buddha and I are just a couple of guys mucking about before the service manual has even been released. We're bound to have some bumps along the way. I just took mine for my last two tec diving classes and couldn't be happier with it.
Center balanced poppet
Lowest friction lever
Short flow path
Huge flows
Easy to service
Those make a winning combination in my book.
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Nice Rob, way more eloquent than my attempt at an explanation. I've been playing with mine for hours. Think I'm golden now. Nice and crisp on/off, stable at 1.1", no leaks, minimal lever play (between diaphragm and lever) about 1/2mm I'd say, does rattle if I shake the case but don't think it's an issue.
Can't wait to try it out again next weekend, might try to sneak a dive in on Wednesday if the stars align.
Will post back after dive number two. Quietly positive. Thanks again for your advice and pointers Rob.
Can't wait to try it out again next weekend, might try to sneak a dive in on Wednesday if the stars align.
Will post back after dive number two. Quietly positive. Thanks again for your advice and pointers Rob.
I wouldn't try it at your first (well, second) dive with it, but I've tuned mine down to 0.9". It breathes like a dream! It's a little ready to freeflow during valve drills, but turning the Venturi to PreDive seems to keep it under control.
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