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Discussion of diving methods and equipment available prior to the development of BCDs beyond the horse collar. This forum is dedicated to the pre-1970 diving.
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Bryan
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First Name: Bryan
Location: Wesley Chapel Florida
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Single Stage Volcano Orifice Repair

Thu Jan 25, 2007 2:41 pm

This has been discussed randomly in the past but I am doing my best to nail down a procedure or two that produces consistent results.

All too often we run across single stage 2 hosers that have had the volcano orifice damaged by sloppy service work or by lack of knowledge on how to properly service the regulator. A dead giveaway is when you open up the nozzle and find multiple springs , washers and sometimes double stacked filters in a effort to put more downward pressure on the seat and stop it from leaking……This sometimes works but the effect on WOB is the same as using a 2’ long snorkel…..

I have had success doing small touchups on the orifice with fine emery paper and sometimes valve lapping compound…..It’s always hit or miss with me.
So I have asked one of our members who is VERY skilled with fine detail work and who has the patience of Jobe to help me with 3 or four leaky single stage nozzles that I have. My hope is that he will find a simple way to clean up imperfections on both sides of the orifice. When he is done I’m sure he will share his thoughts with us and I will post pictures and host whatever information helps to explain his successes with the procedure.

If you have any success stories on the subject please post them below.
Doing it right should include some common sense, not just blindly following specs and instructions. .Gary D, AWAP on SB

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boogerdave
Lung Diver
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Joined: Mon Oct 31, 2005 11:12 am
Location: Destin Florida
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Thu Jan 25, 2007 2:55 pm

On newer regulators with non-removable orifice such as a sherwood brut I have used a pencil eraser to clean up small nicks. Just center the eraser on the orifice and twist back and forth. It takes a while but It has been fairly consistent on cleaning it up.

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Sea Explorer
Master Diver
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Joined: Sun Jun 26, 2005 9:31 pm
Location: Tacoma WA
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Thu Jan 25, 2007 4:03 pm

I believe that it was DACOR that made a cylindrical emery stone for lack of a better term for resurfacing the orifice. It works great. I have one and have used it with great success on even the toughest Mistrals. DACOR Jerry will likely know the specifics on the tool. -Ryan
"A little less conversation a little more action. . ." -Elvis

www.flashbackscuba.com

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Bryan
Plank Owner
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Joined: Fri Jun 24, 2005 11:40 am
First Name: Bryan
Location: Wesley Chapel Florida
Contact: Website

Thu Jan 25, 2007 5:14 pm

I've used the pencil eraser trick myself Dave....It does work pretty good.....Now get back to work before Anna catches you goofing off talking about all this old junk that will get you killed.....

Ryan, Dacor Jerry communicates pretty good with you. Any chance you might hit him up about it the next time you talk?
Doing it right should include some common sense, not just blindly following specs and instructions. .Gary D, AWAP on SB

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boogerdave
Lung Diver
Posts: 57
Joined: Mon Oct 31, 2005 11:12 am
Location: Destin Florida
Contact: Website

Thu Jan 25, 2007 5:18 pm

Anna is off today . . . bwaahhaahahaaaa. . . .

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Sea Explorer
Master Diver
Posts: 119
Joined: Sun Jun 26, 2005 9:31 pm
Location: Tacoma WA
Contact: Website

Thu Jan 25, 2007 5:42 pm

I'll see what I can find out. I will see Jerry in Chicago if all else fails. -Ryan
"A little less conversation a little more action. . ." -Elvis

www.flashbackscuba.com

duckbill

Fri Jan 26, 2007 1:46 am

Pencil eraser with water-mix valve grinding compound.

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captain
Plank Owner
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Joined: Mon Jul 04, 2005 11:32 am
Location: LaPlace, LA

Fri Jan 26, 2007 11:58 am

Truing the nozzle up by grinding can get them to not leak. The problem is this is may only be good to do a time or two, after that the face of the nozzle becomes wider which gets making a leak proof seal harder and to some extent reduces flow. The only real solution to saving those that are too far gone is to devise a replaceable orifice as used on the Spiro Royal Mistral. A custom ground end mill may be able to be made that will true up the nozzle without widening the face of the seat but again there is only so much metal that can be removed each time before there is not enough left for further cutting.
Captain

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Nemrod
VDH Moderator
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First Name: James
Location: Kansas

Fri Jan 26, 2007 5:19 pm

Resurfacing is one way but my Mistral has never needed it--yet. I have thought one could use an end mill and run it through the body--cut all the way through. Then machine a threaded insert with the "workings" and it would be threaded or pressed into the machined body. This would be a project on the order of the Phoenix nearly and made worse by having to modify an existing part---each time.

Another possibility would be, ithout having taken measurments, cut into the body with an end mill removing the volcan, O ring groove etc att the way down to the bottom face and then tak that down to minimum. The machine a intergrated volcano orfice with external O ring groove to seat into the body and the small Oring inside the bottom of the insert. Blleder ports, maybe four would be drilled--number 60 or so--around the volcano insert so there could not be a prressure build up below the insert causing it to unseat and push outward. The spring would keep it seated--again--this would require machining an existing body.

I don't have a simple solution--everything has a finite life and that is why when I saw that the Phoenix would have the REPLACEABLE volcano- that was a huge improvement alone. I wish there was something like that for the Mistral.

Nemrod

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captain
Plank Owner
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Joined: Mon Jul 04, 2005 11:32 am
Location: LaPlace, LA

Fri Jan 26, 2007 7:31 pm

Nemrod, the Spiro Royal Mistral has a replaceable volcano orifice similar to the Phoenix but the Spiro body is about .1" longer to accommodate it.
Captain

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