|
Post by spirou on Dec 12, 2021 9:57:47 GMT -8
Of course I use the titanII, Thanks for the recommendation for the settings of the second stage, I keep you informed.
|
|
|
Post by vance on Dec 12, 2021 15:24:46 GMT -8
Yes, it is a 3K yoke.
|
|
|
Post by vance on Dec 12, 2021 19:03:24 GMT -8
Fred, Please keep us informed about how your "Trieste" evolves. I sent you some hints on how to upload photos, as well as how to improve the cracking effort and the venturi. I hope you will update us with photos! Cheers, Phil
|
|
|
Post by spirou on Dec 13, 2021 11:06:04 GMT -8
Hi Phil, I will keep you informed about what I have done to the first stage to reduce the compensation, was also a way in my mind.
But before I would try the new diaphragme, because I suspect that the diaphragme in place could not be perfectly efficient, last evening, I open the cans and there are a bit water in, but no water on the inhalation valve of the mouthpièce. I suspect the size of the diaphragme in place.
|
|
|
Post by spirou on Dec 13, 2021 12:46:46 GMT -8
|
|
|
Post by spirou on Dec 13, 2021 12:48:19 GMT -8
|
|
|
Post by spirou on Dec 13, 2021 12:50:38 GMT -8
|
|
|
Post by surflung on Dec 13, 2021 14:11:02 GMT -8
Ahhh. A modified DBE. That's interesting! I dislike duckbills. I don't care much for Duckbills either. Duckbill eliminators are kinda scarce for now, but I did have one left for this special occasion thanks to VDH. Here's the good looking prototype diaphragm from Death Wish Engineering, and the slightly modified DBE installed in the Trieste. This is going to be good. This is exciting. I would like to order a new diaphragm for my Trieste, too. I actually have an original Bill Tucker diaphragm but I screwed it up. Here's my story: I should not have taken it apart BUT it had been installed with silicone glue and got offset so that only a little of it was gripped by the side and the glue. So when I got it, it breathed great. But for some reason I opened it up and discovered the edges was just barely hold on... I've had a diaphragm slip on me before so I thought I better change it out for the new diaphragm. But as has been stated numerous times here, the new diaphragm is too small and (for me) was impossible to assemble back into the Trieste. I could NOT get the edges to stay and seal. So, I looked back to Bill's diaphragm to see if I could get THAT one to install. It had a ripple or wrinkle in it caused by the silicone glue and would not stretch to the edges of the Trieste can. I did some trimming of the excess silicone glue and that helped get it to stretch enough. But then I ran into the same difficulty of keeping it aligned during installation. So, I GLUED it to the top can with the duckbill behind it. Once the glue dried, thie held it in place so that I could assemble the cans. The SUCK test revealed no leaks. And when I tested it at the pool it worked. But, it didn't work well anymore and it now had a bump or thump in the breathing cycle... I think that is the wrinkle causing a clunk in the diaphragm movement. I dove it a few more times but kind of lost enthusiasm. Now I see you guys are working on a new diaphragm that's more sensitivce and easier to install! Oh YEAH I want one please.
|
|
|
Post by vance on Dec 13, 2021 15:57:37 GMT -8
First, good work on getting your photos posted. That's always a milestone for new members! Second, I believe you are correct. Water is passing the diaphragm flange due to the too small diameter. James is going to be busy making Trieste diaphragms! He should get very good at it.....
|
|
|
Post by vance on Dec 13, 2021 16:12:54 GMT -8
Hi Phil, I will keep you informed about what I have done to the first stage to reduce the compensation, was also a way in my mind. But before I would try the new diaphragme, because I suspect that the diaphragme in place could not be perfectly efficient, last evening, I open the cans and there are a bit water in, but no water on the inhalation valve of the mouthpièce. I suspect the size of the diaphragme in place. Fred is right. There are problems with the shape of the original Trieste diaphragm. This problem has been made worse by a copy that is too small in diameter. I have been emailing Fred about how to improve the venturi and the cracking effort. I suggested using JBWeld to close one of the two small jets in the second stage, and to back the second stage body out by half turns until it leaks, then take it back down 1/2 turn. With some tweaks and a new diaphragm, his reg should be a good performer.
|
|
|
Post by SeaRat on Dec 13, 2021 18:55:03 GMT -8
I've written quite a bit on the Trieste II that I've had since the 1970s when I bought it new. There are three different engineering design errors which affect the Trieste and Trieste II's performance. Here they are: --The Trieste allows too much air back into the case, instead of for the Venturi down the intake horn. --There is "slop" in the nozzle, which allows it to be slightly off of right down the horn. --The diaphragm has a "set" in it, and needs to be replaced. I've detailed my modifications in a post on a separate thread: vintagescuba.proboards.com/thread/4346/voit-trieste-regulatorIf modified, the Trieste and Trieste II are the best double hose regulators around. If the Venturi is modified the way I explained in the other thread, you will need to change the mouthpiece. At first I put a Healthways Gold Label deflector plate into a USD/Voit mouthpiece, and this worked well for a number of yours (though on one dive it became displaced, and adhered to the intake non-return, blocking air completely, necessitating my switch to my MR-12 octopus for the rest of the dive). A better solution, which I have now, is the VDH DSV Mouthpiece. That is a very good mouthpiece for the modified Trieste II. You can see it on my Trieste II in this short video. John
|
|
|
Post by antique diver on Dec 13, 2021 18:57:53 GMT -8
I don't care much for Duckbills either. Duckbill eliminators are kinda scarce for now, but I did have one left for this special occasion thanks to VDH. Here's the good looking prototype diaphragm from Death Wish Engineering, and the slightly modified DBE installed in the Trieste. This is going to be good. This is exciting. I would like to order a new diaphragm for my Trieste, too. I actually have an original Bill Tucker diaphragm but I screwed it up. Here's my story: I should not have taken it apart BUT it had been installed with silicone glue and got offset so that only a little of it was gripped by the side and the glue. So when I got it, it breathed great. But for some reason I opened it up and discovered the edges was just barely hold on... I've had a diaphragm slip on me before so I thought I better change it out for the new diaphragm. But as has been stated numerous times here, the new diaphragm is too small and (for me) was impossible to assemble back into the Trieste. I could NOT get the edges to stay and seal. So, I looked back to Bill's diaphragm to see if I could get THAT one to install. It had a ripple or wrinkle in it caused by the silicone glue and would not stretch to the edges of the Trieste can. I did some trimming of the excess silicone glue and that helped get it to stretch enough. But then I ran into the same difficulty of keeping it aligned during installation. So, I GLUED it to the top can with the duckbill behind it. Once the glue dried, thie held it in place so that I could assemble the cans. The SUCK test revealed no leaks. And when I tested it at the pool it worked. But, it didn't work well anymore and it now had a bump or thump in the breathing cycle... I think that is the wrinkle causing a clunk in the diaphragm movement. I dove it a few more times but kind of lost enthusiasm. Now I see you guys are working on a new diaphragm that's more sensitivce and easier to install! Oh YEAH I want one please. Hang in there Eben. I think we will have something pretty good to work with before long. Taking my specs on shape and dimensions, James has put together a good mold and cast a really soft diaphragm that fits the Voit cans well. I have spent a lot of time bench testing the prototype with different lever heights, Intermediate pressures and venturi adjustments. Also a little destructive testing that was accidental but helpful in advancing to another version that should be in my hands on Friday. About the Trieste you obtained, considering the deformed condition I suggest you not dive with it for now. I think I know who was the original owner of that one that I built the diaphragm for (unless someone else was making them in the same manner). It would have been at least as far back as 2010, and the person kind of faded out of the vintage dive scene not long after. I'm pretty sure he had opened it up, and maybe never got the diaphragm back in place correctly.
|
|
|
Post by antique diver on Dec 13, 2021 19:14:03 GMT -8
I've written quite a bit on the Trieste II that I've had since the 1970s when I bought it new. There are three different engineering design errors which affect the Trieste and Trieste II's performance. Here they are: --The Trieste allows too much air back into the case, instead of for the Venturi down the intake horn. --There is "slop" in the nozzle, which allows it to be slightly off of right down the horn. --The diaphragm has a "set" in it, and needs to be replaced. I've detailed my modifications in a post on a separate thread: vintagescuba.proboards.com/thread/4346/voit-trieste-regulatorIf modified, the Trieste and Trieste II are the best double hose regulators around. If the Venturi is modified the way I explained in the other thread, you will need to change the mouthpiece. At first I put a Healthways Gold Label deflector plate into a USD/Voit mouthpiece, and this worked well for a number of yours (though on one dive it became displaced, and adhered to the intake non-return, blocking air completely, necessitating my switch to my MR-12 octopus for the rest of the dive). A better solution, which I have now, is the VDH DSV Mouthpiece. That is a very good mouthpiece for the modified Trieste II. You can see it on my Trieste II in this short video. John I might add that the "slop" in the nozzle position can actually cause one side of the horseshoe lever to extend beyond the SS disc and partially ride on the rubber of the original diaphragm. That couldn't be good for performance. It's pretty easy to fix that with a spacer on the retaining screw so that the nozzle stays aligned. also the original disc is about 1.5" in diameter, and I upped it to 1.625" to be sure the lever didn't touch the rubber. I also found that when my Trieste was fine tuned and equipped with a proper diaphragm I had to go with the DSV mouthpiece to cut out the blowby. Sounds like John beat me to the hot rod work, building a new diaphragm well before I did!
|
|
|
Post by SeaRat on Dec 14, 2021 0:11:16 GMT -8
Your diaphragm looks a lot better than mine. I simply looked at the difference between the original MR-12 diaphragm, made of nylon-impregnated neoprene, and my Trieste diaphragm, made of molded rubber, with a "set" in the molded part, and said, "I'll mimic the MR-12 diaphragm. I got some nylon-impregnated with neoprene at a fabric shop, glued the metal plate to it, and put layers of silicone grease onto the box's diaphragm areas. I then placed ShoeGoo onto the bottom box, put the diaphragm material over it, put another layer of ShoeGoo onto the other side of the fabric, and placed the top box on top of the whole affair. I let the weight of the top box push down on the ShoeGoo, and let it sit for a week. Then I peeled everything apart, trimmed up the diaphragm, and had a perfect diaphragm for my Trieste II. I've now been using it for over 20 years. It still passes the suction test, whereby there is not air leaks at all.
John
|
|
|
Post by antique diver on Dec 14, 2021 7:01:41 GMT -8
Your diaphragm looks a lot better than mine. I simply looked at the difference between the original MR-12 diaphragm, made of nylon-impregnated neoprene, and my Trieste diaphragm, made of molded rubber, with a "set" in the molded part, and said, "I'll mimic the MR-12 diaphragm. I got some nylon-impregnated with neoprene at a fabric shop, glued the metal plate to it, and put layers of silicone grease onto the box's diaphragm areas. I then placed ShoeGoo onto the bottom box, put the diaphragm material over it, put another layer of ShoeGoo onto the other side of the fabric, and placed the top box on top of the whole affair. I let the weight of the top box push down on the ShoeGoo, and let it sit for a week. Then I peeled everything apart, trimmed up the diaphragm, and had a perfect diaphragm for my Trieste II. I've now been using it for over 20 years. It still passes the suction test, whereby there is not air leaks at all. John You just can't argue with something that has worked well for over 20 years!
|
|