vibration in regulator

[Ron]

So I spent the past 6 hours trying to get my green label broxton to not shake my teeth out of my head. Every time I draw a long, slow breath from this thing is vibrates really loud. I have tried rebuilding the nozzle twice on the off chance that the seat, spring, or crown was binding. I changed the horseshoe lever height like three times. I tried C clips and a band clamp. I changed main springs. I also filed the horseshoe lever where it mates with the diaphragm using locksmith's needle files in case it had any rough spots that would cause vibration. I tried changing the intermediate pressure three or four times. I checked the top and bottom cans to make sure that they were true. The only way I can get it to go away is to put a single stage diaphragm in it. With any of the three two stage diaphragms that I have (1 rubber, and 2 silicone), the regulator shakes my teeth out. IP is @ 135 with 400 PSI supply pressure, and the horseshoe lever is currently set at the factory spec of 1.5 turns out. The regulator is completely unmodified. It has the NOS springs in it. I tried it with the modified springs, but the cast bodied broxtons are .030" deeper than a forged body which means that the modified second stage springs will only work with an IP of like 90 @ 400 PSI supply pressure so they are a No-go. Interestingly, with the modified second stage springs in it, the reg does not vibrate. Then again, it doesn't give you enough air either. So, I am out of beer, I have to get up for work in 4 hours, and my stupid regulator still vibrates. I need help figuring this out, before I throw this poorly cast piece of crap into my recycling bin and some 40 year old guy living in his parent's basement has an actual heart attack.

[Robohips77]

another sleepless night. IP is supposed to be 110 isn't it? All your tries have been with no water on reg just with ambient air surrounding it? I am awake and will check my notes. see what i have done in past. vanny

[Ron]

110 is stock IP, but I tried turning the IP down and it does not do any good. I have eliminate the hoses as well, as I have just been taking breaths off of the intake horn. The good news is that the broxton has such a weak airflow that you can literally breathe off the horn. It's definitely no mistral. I also submerged the regulator and pressurized it. There are no air bubbles anywhere, the body gasket is tight, and diaphragm is tight, and the nozzle is tight. I am really at a loss here.

[captain]

A few things to check. Look closely at the contact surfaces of the tabs on the diaphragms, I have found some that have fine serrations that need to be smoothed out. Be sure the diaphragm tabs are making equal contact on the horseshoe. Usually if you just center one side the other side will be slightly off center, both need to be equal even if slightly off center of the tab. I have been able to eliminate most vibration by careful alignment of the diaphragm to the horse shoe and horseshoe height, I think higher is better. Also round off the square cornors of the horseshoe contact surfaces.

[Bryan]

Walk into your local Scuba Store and tell them you want to try diving with one of those double hoses regulators on the wall. They will either collapse in laughter or look at you like you have a horn growing out of your forehead.

Next, you'lll hear one or more of these lines:

Those things are dangerous, and you will die if you use one.
No one makes parts for those anymore, so there are no working examples left.
No one dives with those anymore

[Ron]

Oh vintage diving is alive and well, so much so that ran out of beer.

Thanks for the tips Captain Tom, when I get home tonight I will try all of them.

[Robohips77]

Any updates? I feel responsible

[Ron]

It was the horseshoe. It had deep grooves worn into it from the tabs on the diaphragm. I tried sanding it down, but then it was too short and brittle. No biggie, I just need to find a new lever. Rog, this wasn't your green label, this was the one I found for a song in Florida.

[Robohips77]

I will check to see if I have an exta horse shoe. If so will let you know. good luck on final repair. RVF

[Ron]

I wanted to update this thread, as to not leave anyone seeking answers in the future in the dark. When I replaced the horseshoe lever with a good one sourced from a parts regulator, the green label breathes fine.

Here are some tips for getting your red, green, or early blue label with a rough cast body to breathe well (I don't know anything about the black label, as I have never seen one personally):

-Use the original springs. Tom Madere touched on this in another thread, but the relief of the spring cups on the rough cast body is deeper than on the forged bodies. Tom noticed it on his regulator, and I noticed it on both of my rough cast bodies. This means that the improved springs, which work great on a forged body, will not work in a rough body. I experienced this first hand on a rough body test dive in Ohio. Conversely, the NOS springs, which have the potential to create a terrible work of breathing on a forged body reg due to the reduction in spring cup depth, work great on the rough body. I have dived the improved springs on a forged body to depths of 120 feet.

-Crank the IP as high as you can with the reg on a tank with 300 PSI or so of supply pressure. This usually works out to about 135-140 PSI. DA series (non-aquamaster) regulators seem to like high IP to balance out the amount of force exerted by the second stage springs. If you don't have an IP gauge, then advance the first stage screw until the reg hisses at 300 PSI supply pressure. Back it off 1/8-1/4 of a turn, then mark it with a sharpie. Now you have a base IP.

-Pay lots of attention to the horseshoe. Horseshoes on the original DA series are not like the DAAM series. The angular mating surface of the DA horsehoes makes it prone to wear. Check for grooves or exposed brass. If it's not too bad, finesse it a little with a locksmith's file to smooth out the mating surface and make it less prone to vibration and poor engagement.

-The original specification for setting the second stage lever on a DA calls for the screws to be set at 1.5 turns from fully screwed in. This measurement works great on a rough cast body with stock springs. On a forged body with stock springs, you will have too much tension on the spring. Don't take my word for it, try it. I usually end up with anywhere from 2-2.5 turns out on a forged body DA with improved springs. The improved springs are the ones that Bryan sells in his kit. I surmise that the original spec for the tune was carried over from the rough cast body, along with the springs. This means that the delta is in the forged body, with its shallower springs cups.

[Greg Barlow]

Ron,

Thanks for the interesting update. Even though I don't own a rough cast body, I read it carefully. Experiences such as yours prevent others from "reinventing the wheel". My experience with HP pin length in the Voit single stage upstream regulators is a similar situation. It took me more than 8 hours work to finally solve the issue.

Greg

[captain]

You can use 400 grit emery cloth to smooth and round the horseshoe ends and the diaphragm tabs. The thin diaphragm tabs and the square edged horseshoe ends was a really bad design, like a dull knife cutting a groves in the ends of the horseshoe. Back in the day it probably wasn't an issue because the horseshoe was replaced with a new one during rebuilds.

[Ron]

So I FINALLY figured out what the hell that vibrating/honking was. Look at that diaphragm closely and tell me what you see...

[DrunkenParrot]

So I FINALLY figured out what the hell that vibrating/honking was. Look at that diaphragm closely and tell me what you see...[/quote]

All I see is a very good beer..... but your mileage may vary

[Drado]

Well, that took a while to figure out

Did changing the HP diaphragm cure the symptoms?