|
|
Post by time2dive on Oct 25, 2006 22:37:35 GMT -8
I just picked up a Silver Snark III as well as a Mistral and a set of twin 38's. Now the Mistral and the tanks I can figure out, however I know little to nothing about the Nemrod. It appears to be in good shape, I will put it on a tank Friday or Saturday. For those of you that know more about the Nemrods than me, can you tell me anything about it.
I do have a repair guide for the Silver Snark.
I will rebuild the Mistral and dive the 38's with my Other vintage regs.
Tim
|
|
|
|
Post by swimjim on Oct 26, 2006 3:14:36 GMT -8
I don't have the "silver" but I do own and early "60's Snark III. I just cleaned mine up and dove it pretty much. Beautifly made and a real smooth breather. The only fly in the ointment was the exhaust mushroom was shot. I searched high and low and was unable to find a replacement. I fit it with a duckbill and that seems to work just fine.
Jim
|
|
dj793
Senior Diver
Posts: 67
|
Post by dj793 on Oct 27, 2006 8:07:33 GMT -8
I also own an older Snark III like the one I learned on in the early 60's, and recently picked up a Silver, haven't tried it yet but inside it looks new. My daughter dives a rebuilt DA and swears the Nemrod is a better breather. I wouldn't part with it for anything. On the repair side there is, on e-bay a guy in Chicago that has booklets, just go under vintage scuba then into his site...I also believe I saw some in Dans store.
|
|
|
|
Post by SeaRat on Oct 27, 2006 8:28:09 GMT -8
A long time ago, I concluded that the older Snark III (and maybe the Snark III Silver) had a slight design problem--the venturi jets went up and hit the diaphragm, deflecting it back toward its normal position. I took a plastic milk container, cut out a piece of plastic to make a baffle, and inserted it into the screw holes to block the venturi air from hitting the diaphragm, which also channeled that air toward the intake tube. This baffle was high enough to not block the venturi, but not so high as to interfere with either the lever system or the diaphragm (it took a bit of cutting to get it right). With that modification, it became a really great breathing regulator (with a USD hose/mouthpiece system too).
John
|
|
dj793
Senior Diver
Posts: 67
|
Post by dj793 on Oct 27, 2006 9:45:24 GMT -8
Searat, interesting, I don't suppose you have a picture or drawing of size and positioning.
|
|
|
|
Post by SeaRat on Oct 27, 2006 20:37:19 GMT -8
I did not, but I decided it was time to get the ol' regulator out and break it apart to see whether I did something to it last summer. I did dive it a few times without non-returns, so it was important to see inside. As usual, I got all the clips off but one, and spent about ten minutes getting it off--Murphy is at it again. I also want to re-apply some silicone grease to the mushroom non-return exhalation valve, and the diaphragm. So it was time, and tonight I got the new Canon PowerShot SD500 out, put it on the macro function (flower), and took a few photos:  This photo shows the lever system, and the baffle in front of the inhalation tube.  This photo shows the top view of the baffle, and shows how it is screwed into the two screws which hold te top box onto the first stage body. |
|
|
|
Post by SeaRat on Oct 27, 2006 20:38:53 GMT -8
 The third view shows the baffle from the top. Note that the nozzles are completely blocked from shooting air onto the LP diaphragm.  This final photo shows the baffle from the view down the intake tube, illustrating how this simple modification channels air from the venturi tubes down the intake tube, without allowing that air to disturb the LP diaphragm. 'Hope this helps. Please realize that this is a modification of a commercial life support system, and that you alone are responsible for your safety if you try it. Be sure that you test it on land, then in a pool under supervised conditions if you decide to do this to the Snark III. I take no responsibility for what anyone else does to their regulator, and am simply showing you how I modified my own. John |
|
dj793
Senior Diver
Posts: 67
|
Post by dj793 on Oct 27, 2006 22:50:00 GMT -8
Thankyou SeaRat! Once I get the Silver tested out this may be a project for the snowy days ahead. I don't know way Nemrods aren't more popular, when I sstarted diving in '62 the dive shop recommended it over the USD. It has never given me trouble in any way and it breathes nicely.Thanks again.  |
|
|
|
Post by duckbill on Oct 28, 2006 11:00:24 GMT -8
John,
It shows up in the photos but might be hard to see by eye that there is cracking in the plastic around the screws. Just be sure the plastic doesn't come loose inside the regulator.
I was having trouble with one of my Mistrals vibrating during inhalation and ruining the seat. Usually I am able to tune out any vibration, but on this one I tried everything to no avail. One of the things I tried was to block the side vents on the venturi nozzle to prevent air from blasting against the diaphragm which I suspected might have been causing the problem. I'll tell you.....I wasn't prepared for the blast headed down the hose! I have heard that a blast was one of the objectionable features of the DW and why those side vents were incorporated into the Mistral's nozzle, but I think it must have been worse with the longer Mistral nozzle pointing directly down the horn. Anyhow, I haven't detected any embolism from the incident, but people need to be very careful when they experiment with directing more than just the right amount of air down the inhalation hose. BTW, the problem was a flimsy diaphragm. The Mistrals seem to prefer some beef to their diaphragms to prevent initiating a resonance.
|
|
|
|
Post by SeaRat on Oct 28, 2006 12:13:46 GMT -8
Nemrod,
Thanks for the keen eyes, spying the cracks. These are stress cracks, due to the curve in the plastic. But the plastic itself is well captured by the screws. I don't see a problem right now, but may replace the plastic anyway as I clean up the regulator (it also has some minor corrosion).
I also have tried blocking those Mistral holes, and it did not work, as you described. One thing I did do was to put teflon tape around the orifice, for more tension, and simply left them horizontal rather than verticle to the regulator box. That way, the secondary air at least had to hit the metal box sides before hitting the diaphragm.
John
|
|
|
|
Post by time2dive on Oct 29, 2006 22:54:19 GMT -8
|
|
|
|
Post by time2dive on Oct 29, 2006 23:00:23 GMT -8
|
|
dj793
Senior Diver
Posts: 67
|
Post by dj793 on Oct 30, 2006 19:56:28 GMT -8
:)That's the same model I picked up a couple months ago, it is now ready to try..it needs new hoses but that can wait alittle while, they appear to be diveable, they have a small crack in one hose which I put temporarily on the exhale side. Good luck with yours.be |
|
|
|
Post by duckbill on Oct 30, 2006 22:24:34 GMT -8
FYI, the Nemrod Snark III is also a double hose regulator the Navy was using in training up to at least a few years ago.
If you ever get a chance to see "Navy SEALs Training: BUD/s Class 234 The Only Easy Day Was Yesterday" on the Discovery channel, you'll see plenty of them. I didn't know anything about the Snark III until I saw that show and asked for help on a forum in trying to identify them.
|
|
Deleted
Deleted Member
Posts: 0
|
Post by Deleted on Oct 31, 2006 6:47:51 GMT -8
Not that this matters much, but this is the first time I have seen a Snark III disassembled..........the can looks an awful lot like a early Dacor C-3.........1st stage housing is different. Even the concept of the twin lever linkage is the same.....although formed different............the Dacor's are unbalanced 1st stages however.
Can anyone tell me who came out first, Dacor or Nemrod, with their designs?
|
|
