Scubatools.com , trying to understand purpose/logic of a couple 2nd stage tools ?

[scubafanatic]

Scubatools has lots of interesting looking tools, but I'm trying to wrap my head around (generally) how they work ? My overall purpose is I'm learning how to do my own 2nd stage orifice adjustments on my Scubapro Mk 5 / 109's (upgraded to fully balanced 156 standard) I've got (on order now from Scubatools) a small stubby screwdriver so I can make these adjustments manually (trial and error method) but wondered if any/all these 3 tools below would make that adjustment process easier ?

Dual Drive Inline Adjusting Tool

Gauge for Dual Drive Adjusting Tool


Vintage Double Hose has this tool:

Shop Online

Thanks in advance, Karl

 

[AFdivedoc]

The inline adjusting tool definitely makes tuning the second stage easier. Without it, you have to depressurize/purge and disconnect the second stage from the hose between incremental adjustments of the moveable orifice on your 109. With the inline adjustment tool, you simply connect it between the second stage and the hose, turn on the pressure, and tune to your heart's content before reversing the process for removal of the tool. The IP gauge is overkill if you already have one.

 

[Scared Silly]

When you rebuild the orifice must be seated so it does not free flow. So to determine that position the reg needs to be under pressure. The in line tool goes between the hose and the second stage and mates to the orifice so it can be screwed in or out as needed for seating. As said above, with out the tool the process is really trial and error. Which is fine in field but not for rebuilds.

If you are doing just your own the VDH tool would be fine as the other mates to both slotted and hex head orifices.

As for the pressure gauge - you need something to check the intermediate pressure for the first stage. If you already have one then not really any need on that tool but I have one on mine as it does make it nice to check when rebuilding.

 

[scubafanatic]

The inline adjusting tool definitely makes tuning the second stage easier. Without it, you have to depressurize/purge and disconnect the second stage from the hose between incremental adjustments of the moveable orifice on your 109. With the inline adjustment tool, you simply connect it between the second stage and the hose, turn on the pressure, and tune to your heart's content before reversing the process for removal of the tool. The IP gauge is overkill if you already have one.

Thanks for the insight. Sometimes how things work only become apparent when one has the hardware and tools in hand, I might take a chance on a purchase now and if I have more questions once everything is in hand I'll be back picking everyone's brains.

---------- Post added July 28th, 2014 at 01:14 AM ----------

When you rebuild the orifice must be seated so it does not free flow. So to determine that position the reg needs to be under pressure. The in line tool goes between the hose and the second stage and mates to the orifice so it can be screwed in or out as needed for seating. As said above, with out the tool the process is really trial and error. Which is fine in field but for rebuilds.

If you are doing just your own the VDH tool would be fine as the other mates to both slotted and hex head orifices.

As for the pressure gauge - you need something to check the intermediate pressure for the first stage. If you already have one then not really any need on that tool but I have one on mine as it does make it nice to check when rebuilding.

I've got about a dozen 109's needing possible adjustment (and lots of other non-Scubapro regs in the fleet too) so I may chance a purchase since it will be very time consuming to do all of them manually.

UPDATE: OK, so I just ordered those 3 tools tonight, so it looks like I'm committed to this little DIY project! Stay tuned.

 

[halocline]

You can adjust the cracking pressure on 2nd stages just fine without one of the inline tools, it just takes a little longer, meaning maybe 5-10 minutes instead of a few seconds. It means a lot if you're doing them all day but for a hobbyist doing his own regulators it's probably not worth $70, at least to me it would not be. But it does allow you to determine the exact spot where the reg begins to flow, although you would not want to leave it there, and actually that spot changes as the seat wears in.

The idea of having the IP gauge right at the 2nd stage junction has some appeal to me, because I believe the IP gauges mounted on the end of the LP inflator hose do not give an accurate representation of IP drop during inhalation, due to venturi forces in the 1st stage IP chamber. I think these forces draw down pressure in the LP inflator hose when air is flowing quickly to the 2nd stage.

 

[LeadTurn_SD]

...

UPDATE: OK, so I just ordered those 3 tools tonight, so it looks like I'm committed to this little DIY project! Stay tuned.

Welcome to the "Dark Side"!!

Keep us posted on how your project goes; if you run into any problems the "Usual Suspects" on this board are terrific about lending a "virtual" hand. They have tons of experience with -109's and can certainly steer you in the right direction if you have questions along the way.

Best wishes.

 

[rhwestfall]

Word of warning: when you are adjusting the orifice, make sure and press the lever/diaphragm or you will cut up the seat....

press, turn, release, listen.... repeat as necessary

 

[scubafanatic]

Word of warning: when you are adjusting the orifice, make sure and press the lever/diaphragm or you will cut up the seat....

press, turn, release, listen.... repeat as necessary

OK, I'm seeking clarification, so please confirm my understanding below:

if I use a screwdriver to adjust the orifice, meaning the reg is NOT pressurized while I'm adjusting the orifice, I need to press the lever/diaphragm down while simultaneously turning the screwdriver on the orifice.

If I instead use the inline adjustment tool, and DO have the reg pressurized while adjusting the orifice, then I do NOT need to be pressing down on the lever/diaphragm while simultaneously using the inline adjustment tool.

...is this correct ?

 

[ams511]

You should always depress the purge to move the seat away from the orifice. I am not sure but would guess that metal orifices would cut the seat easier than a plastic one.

 

[Hickdive]

With an in line adjuster the regulator should be pressurised otherwise you obviate the whole point of the in line adjuster.

OTOH if you depress the purge on a pressurised reg whilst using an in line adjuster then air will escape from the reg and again you'll obviate the reason you're using an inline adjuster in the first place i.e. to adjust the orifice until no air comes out.

Yes, the orifice can indent the seat if you don't depress the purge but unless you spend a good few minutes grinding the orifice back and forth you'll put no more damage on the seat than the first dive after service will anyway.