Conshelf XIV/Mares MR-12 interchangable parts?

[TRRJ]

Im looking to get into some overhauling with old USD conshelf xiv's and ive run into a slight problem.
My problem is that here in australia we do not have access to all the parts on the aqualung parts list and i cannot get a DIN kit (sku 107455) at all and i cant get a dry environmental kit(100525) online. The CWD kit will cost me 170 plus labour(not allowed to buy 'service parts') so i want to avoid getting it locally if i can.

My options so far have been to buy the reg with these parts already or to source them online, which is proving to be pretty hard.
The last option that i seem to have stumbled upon was the possiblity of getting mares part kits for my conshelf as i have heard whisperings of these two first stages having interchangable parts. If anyone ould tell me the truth behind these laims i would be forever indebted as the the mares kits are cheap and avaiable at leisurePro.

Thanks, tristan.

 

[Luis H]

I have found that the HP seat and O-rings are interchangeable, but the yoke is not. The threads for the yoke (and DIN adapter) are different pitch. The diameters are almost the same, but I am guessing that Mares is using a metric thread.

I don't know about the environmental kit threads, but it is likely that Mares is using metric threads.



There are a couple of reasons why some of the parts are interchangeable.
Voit was bought or absorbed by Mares. Mares has then used many of the old Voit designs. In the early days a lot of the Voit regulators were made by US Divers (Voit made the rubber parts for US Divers).

The secondary reason is because the entrance size of all regulators is driven by the yoke valve size opening (0.5 inches). If you design a regulator similar to the Conshelf (where the seat is installed from the valve opening side), it is likely that the dimensions are going to be the same.


It makes sense now-a-days for Mares to use the same size HP seat (since it is driven by the valve opening and it is backwards compatible), but there is no incentive in using the same size threads as US Divers (now Aqua Lung).

Actually, even back in the late 60's (or early 70's) when Voit introduced their own design double hose (the Trieste), they used different size threads in the second stage body. They were not metric threads, but they were different pitch (same diameter). We haven't figured out why.