|
Post by wpadiver on Nov 16, 2018 21:25:14 GMT -8
Thanks for the link. Lots of stuff to think about there.
Jim
|
|
|
Post by nikeajax on Nov 17, 2018 10:51:55 GMT -8
Another way to make the Scuba diaphragm is to find a convex-form to stretch nylon fabric over; I think something about the size of an American-softball: The idea is to make a dome-shape. Next, with either liquid silicone or liquid neoprene, massage and force the uncured liquid into the fabric. Once this has cured, turn over and repeat: I think twice each side should be more than sufficient. Cut to a manageable size, but leave working room, test fit, and if you've done it right you can glue and fasten down... JB
|
|
|
Post by SeaRat on Nov 17, 2018 18:14:48 GMT -8
I have posted this before, but here's some more info on the exhaust diaphragm for the Healthways original Scuba regulator. Here is the original diaphragm on the Healthways Scuba. The rubber band is to cover the holes in the exhaust tube (which is an auxillary exhaust if the exhaust diaphragm gets stuck to the metal tube; some regulators don't have holes in the exhaust tube). Here is the entire regulator, broken down to parts. This shows the rubber band covering the exhaust holes in the exhaust tube. Here's one way to make an auxiliary duckbill for the Healthways Scuba (I say "auxiliary" because it is only functional in the head-down position). Here is an exhaust diaphragm made from a latex glove. I found it to be the right flexibility for this diaphragm, but somewhat fragile. I subsequently made one of two layers of a blue nitrile chemical glove, which has the same flexibility, but is much more resilient to chemicals, water and sunlight. Because in this photo there are a lot of small wrinkles, this configuration leaked a little. My final version, with the two layers of blue nitrile material, also incorporated using Shoe-Goo around the outside to ensure that the wrinkles did not leak. Note also that this is my Hybrid Healthways Scuba, with the box of the original but the innards of the Gold Label. I also covered the metal flange with silicone grease so that the Shoe-Goo, when it dried, would not stick to the metal. It is a fantastic regulator in this configuration. Hopefully, this will help you in making your Healthways Scuba exhaust diaphragm. John
|
|
|
Post by scubalawyer on Nov 22, 2018 7:51:26 GMT -8
I saw that folks are discussing various means of reproducing a 1st Gen. Healthways SCUBA Exhaust Diaphragm. Here is my latest attempt to do so. It is still a work in progress. I previously posted this on VDH but thought you guys might find my experiments interesting. I first used sulfer-less plasticine clay to insert my existing diaphragm into. I then poured the first half of the silicone mold and let it set overnight. That gave me side one. After pouring the second side and waiting another day I now had my mold. I then used a different silicon compound and cast the replica. Needs a little trimming but not bad for a first try. Original next to duplicate. Still experimenting. Color is a little off and consistency ain't perfect yet. Color is better, and it would likely work, but still too soft and bendy in my opinion. Back to the drawing board for strengthening the tetravalent polymer chains. Mark
|
|
|
Post by nikeajax on Nov 22, 2018 8:41:02 GMT -8
Mark, excellent work: thank you for sharing; oh, and welcome aboard too!
Jaybird
|
|
|
Post by scubalawyer on Nov 22, 2018 8:55:01 GMT -8
Mark, excellent work: thank you for sharing; oh, and welcome aboard too! Jaybird Thank you J!
|
|
|
Post by nikeajax on Nov 22, 2018 10:34:46 GMT -8
So, SL-Mark, have you tried this mod yet? It turns a decent reg into an outstanding reg JB
|
|
|
Post by scubalawyer on Nov 22, 2018 11:00:50 GMT -8
So, SL-Mark, have you tried this mod yet? It turns a decent reg into an outstanding reg JB I have not, but always willing to explore alternative realities. M
|
|
|
Post by nikeajax on Nov 22, 2018 12:00:49 GMT -8
Just so you know, if you do try it, you will have to change the orientation of the alignment-holes or, turn the valve-body: these original Scubas didn't have the valve body turned to an optimal position...
JB
|
|
|
Post by tomcatpc on Nov 22, 2018 18:50:39 GMT -8
This topic is still active? This one sure has morphed from when I started it...Ha ha. Mark
|
|
|
Post by nikeajax on Nov 23, 2018 11:44:00 GMT -8
So, SL-Mark... What if... you reinforced your diaphragm with something sheer, like silk or polyester? Go to a thrift store and hit the women's department, it should be very easy to find some really light-weight fabric that you could work into your mold. Just brainstorming bruddah! JB
|
|
|
Post by scubalawyer on Nov 23, 2018 12:58:08 GMT -8
Excellent idea JB! I have given this idea some thought. Ideally, I would like to have the perfect polymer mix to just have a reproduced silicone diaphragm that will work. So far I am not entirely happy with my results but continue to experiment. I have been looking at the fabric reinforcement concept. The reproduction diaphragm itself is too thin to incorporate fabric directly. I have been looking at laying nylon over the finished reproduction and then "painting on" another thin layer of silicone to hold the material in place. There are a few silicone to silicone bonding issues I need to solve first - I knew I kept my old college chemistry textbooks for a reason. All ideas and suggestions are welcome. It's not like I don't have a crap-ton of other stuff to do in my life but this is one of those projects I work on here and there and will continue to do so until I either have success or all of my attempts end up FUBAR. M
|
|
|
Post by nikeajax on Nov 23, 2018 13:46:36 GMT -8
SL-Mark, what about cotton-gauze: like out of a first-aid-kit? The cotton would completely absorb the liquid silicone, making it water-proof. I think it would be just enough reinforcement for your needs and the loose weave will allow you to have it very easily conform to your soft mold. By its self it's not strong, but when it's part of a matrix, that changes... I have an old house from 1926, so when I need to patch a large hole, I mix cat-fur into the plaster, they used to use horse-hair to reinforce it. The clumps of my little orange buddy's fur keeps the plaster from sloughing away while it cures: once it's cured, it's super strong. Gauze and silicone will very probably do the same thing: keeping it from tearing in a fast entry into the water... Like rayon-reinforcing in tires, or as DRW calls them tyres JB
|
|
|
Post by scubalawyer on Nov 23, 2018 14:08:16 GMT -8
SL-Mark, what about cotton-gauze: like out of a first-aid-kit? The cotton would completely absorb the liquid silicone, making it water-proof. I think it would be just enough reinforcement for your needs and the loose weave will allow you to have it very easily conform to your soft mold. By its self it's not strong, but when it's part of a matrix, that changes... I have an old house from 1926, so when I need to patch a large hole, I mix cat-fur into the plaster, they used to use horse-hair to reinforce it. The clumps of my little orange buddy's fur keeps the plaster from sloughing away while it cures: once it's cured, it's super strong. Gauze and silicone will very probably do the same thing: keeping it from tearing in a fast entry into the water... Like rayon-reinforcing in tires, or as DRW calls them tyres JB
|
|
|
Post by scubalawyer on Nov 23, 2018 14:10:06 GMT -8
Cotton-gauze? Interesting. I'll ad it to the list of potential fillers.
Thanks,
M
|
|