Siebe Gorman/Heinke Mistral

Dedicated to the discussion of vintage diving methods and equipment available prior to 1970. This forum section is limited to the diving without modern BCDs or use of an Octopus.

Moderators: simonbeans, captain

Forum rules
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.
User avatar
Master Diver
Posts: 376
Joined: Fri Jul 29, 2005 6:42 pm
Location: Melbourne, Australia

Re: Siebe Gorman/Heinke Mistral

Tue Jan 24, 2017 5:48 pm

I have a similar one, in like new condition. The rugged construction makes you aware that these regulators were made by a 'hard hat' company.

Like most of the divers here in Australia who use them, I rotated the cans to put the hoses on the opposite sides. That puts the HP port at the top. The original HP hose has a 90 degree fitting and the gauge then goes over the diver's shoulder. The 'over the shoulder gauge hose' is better and you do not bang the gauge on rocks while diving. The label is turned 90 degrees, but, that is a small price to pay. The small regulator yoke was made to be used on a British 'pillar' valve, similar to the early USD valves. Pillar valves do not have burst discs or HP caps, to interfere with placement either. Inverting twin yoke manifolds also works if you want to leave it in the original configuration.

With the horns switched by rotating, I can put the regulator on almost all of my valves, except the heavy DIN/yoke variant. The yoke simply is too small for some valves. The 90 degree hose horns put the regulator a bit too high, so I replaced them with Heinke Mk I horns, which are straight. Some divers rotate the horns to point up, so they can lower the regulator on the diver's back. However, the cans must be rotated a bit differently or they will face each other..

I found that I did not have enough adjustment in the four can clamps, when I used a silicone diaphragm, but my original diaphragm worked okay.It would be interesting to see if a band clamp would fit. When Siebe Gorman merged with Heinke in 1960, current stocks of mouthpieces continued to be used. They also began to use small stainless hose clamps, as the original bent brass (no nut) tended to strip. Mine came with Heinke Mk III hoses. (They have a place for a cart wheel valve.)

A little silicone grease on the contact points smoothed things out very well.

Return to Classic Vintage Diving

Who is online

Users browsing this forum: No registered users and 1 guest