Propane Regulator: What's Going On???

AVTrout · #1 2024-05-09, 9:33am

I've taken a few years off of torching, and now I don't remember how to do the thing.

I have a new regulator and it has two round gauges on top: 1 for acetylene and one for propane. I use propane.

Can I ignore the entire acetylene gauge reading? That's what I've been doing.

Here's how I remember setting the regulator:
1. open the knob on the propane tank a few good turns.
2. light torch, turn on oxy con, adjust flame.
3. adjust regulator by the T handle on the top to the amount of propane my torch can handle (Hellcat, 4-7psi).
4. make beads.
5. turn off oxy con.
6. turn off propane.
7. bleed line.

The problem is, my regulator is difficult to use. I don't remember the old one being like that. I can turn the T handle until the end of time and very little happens. I can turn it off! And the propane continues to come out. BUT.... if I merely nudge the propane knob, the pressure jumps on the gauge. It's impossible to set it purposefully to 7psi because it's so sensitive. I fool around with it for a half hour or so, and eventually, I just give up and run it at 8psi because that's where the gauge seems to want to stay at. Adjusting the T knob does very little to nothing. I have to adjust it by the tank knob.

In the past, it was a 1 time set-up, I didn't have to constantly step out and adjust the tank. Previously, I turned on the propane, adjusted the T knob to where I wanted it, and torched. When I was done I would turn off the propane knob, bleed the lines, and when I was ready to torch again, I'd just turn on the propane knob and the correct amount of propane would flow out, as I'd previously adjusted it with the T knob.

Not so with the new regulator. Is it possible the new regulator doesn't work properly?

Any advice would be appreciated.

kevingreenbmx · #2 2024-05-09, 10:17am

The two gauges are much more likely the high pressure (bottle side) gauge and the low pressure (regulated side) gauge.

post a picture of what you have, but to me it sounds like your regulator has a bad diaphragm or you are turning the regulator knob the wrong way.

KJohn · #3 2024-05-09, 11:35am

it sounds like it's failing. Mine fail about once a year. I now buy them off Amazon for half the price of the suppliers. But I have a cover for the tank this year and I hope it helps.
Anyway, it should regulate the propane at whatever pressure you choose, or there's a problem. Side note that weather especially very hot weather can affect the pressure in the tank or hose, so you might have to let the pressure settle over a min or two. And adjust at the tank again after, but that should be it.

I wouldn't turn off the oxycon until you bleed the line. So much easier to light to torch and let it run out. Faster too and you don't have all that gas around.

kevingreenbmx · #4 2024-05-10, 5:47am

I keep a stock of spare parts for our National 2500 and 2300 regulators. The diaphragms, seals, and o-rings are only like $1 each, and they are very easy to replace. Much preferable to replacing the whole regulator

KJohn · #5 2024-05-10, 3:48pm

I never thought of being able to repair them! Could you give me some advice please??? It's definitely the o ring or the diaphragm that fails. I hate throwing them out at $100. Geezzzzz

AVTrout · #6 2024-05-10, 7:46pm

Thanks for the advice and input everyone. I ended up buying new hoses and a new regulator.

kevingreenbmx · #7 2024-05-13, 5:52am

Quote:

Originally Posted by KJohn

I never thought of being able to repair them! Could you give me some advice please??? It's definitely the o ring or the diaphragm that fails. I hate throwing them out at $100. Geezzzzz

What kind of advice are you looking for? They are very easy/simple devices to service. the knob/bonnet assembly just threads off the body revealing a stack of easily inspected and re-assembled parts.

I stored the assembly drawings on the Wiki page of the makerspace I melt glass at if you want to see the parts diagrams and assembly instructions for the 2500 and 2300 regulators we have (the ones mountain glass sells)

https://wiki.hive13.org/view/Lampwor...tem#Regulators

KJohn · #8 2024-05-14, 10:21pm

I wish i hadn't thrown it away now. I have one of those for a spare so knowing this, it will come in handy. The assembly drawings are hard to read but useful place to start. Thanks so much for telling me about this!

kevingreenbmx · #9 2024-05-15, 5:42am

Quote:

Originally Posted by KJohn

The assembly drawings are hard to read but useful place to start. Thanks so much for telling me about this!

As soon as you pull one apart and see the parts inside with your eyes, it makes perfect sense.

I attached a picture of the insides of one of the 2500 regulators to this post (Mylar washer is missing in the picture, but it just goes in the bonnet between the bonnet and diaphragm to keep the diaphragm from twisting/distorting as the bonnet is tightened).

No problem! I definitely think most glassblowers are scared of these things, and so never even consider that they are made to be serviceable. Definitely saves money to replace parts vs. the whole assembly.

KJohn · #10 2024-05-16, 12:37am

wow yeah looks simple **famous last words hahaha. So ok is the black the diaphragm?
Is the picture the order that they go in? Man I'm kicking myself now. That regulator I had was 3 months old only.....

kevingreenbmx · #11 2024-05-16, 5:57am

Quote:

Originally Posted by KJohn

wow yeah looks simple **famous last words hahaha. So ok is the black the diaphragm?
Is the picture the order that they go in? Man I'm kicking myself now. That regulator I had was 3 months old only.....

Yes, the black part is the (torn and damaged) diaphragm. it's just a circle of black neoprene rubber.

in order, what you see there is:
1) the body with gauges, fittings, and valve installed
2) the cap, which protects the rubber diaphragm from the valve stem
3) the diaphragm
4) the back-up plate, which protects the diaphragm form the spring end
5) the load spring
6) the spring button, which just acts as a bearing between the spring and knob, making the knob easier to turn
7) the bonnet and knob sub-assembly

KJohn · #12 2024-05-18, 1:29pm

and the mylar washer goes between 2 and 3, or 3 and 4?

kevingreenbmx · #13 2024-05-19, 10:17am

Quote:

Originally Posted by KJohn

and the mylar washer goes between 2 and 3, or 3 and 4?

not really either. It goes between the Diaphragm and the bonnet, on the outer edge of the diaphragm around the back-up plate.

KJohn · #14 2024-05-19, 2:49pm

ok there's a lot of stuff between the diaphragm and bonnet. Just somewhere in there?
And where can we get spare parts from? I'm pretty sure it's the diaphragm that weakens.

kevingreenbmx · #15 2024-05-20, 6:10am

Quote:

Originally Posted by KJohn

ok there's a lot of stuff between the diaphragm and bonnet. Just somewhere in there?
And where can we get spare parts from? I'm pretty sure it's the diaphragm that weakens.

The Mylar Washer is a thin, large diameter ring that only touches the diaphragm on the outside rim, where it's pinched directly between the bonnet and body.

All the other parts, the backup plate, spring, and spring button, go between the diaphragm and the knob, inside the bonnet and Mylar washer.

I ordered the spare parts directly from Premier Industries (who owns the National Torch brand). They do have a $50 minimum order, so I ordered multiples of all the common replaceable parts for the regulators we have (6x 2500 and 3x 2300) so that I could meet the minimum and know I had parts on hand when something failed. I attached the list of stuff I ordered, with prices.

KJohn · #16 2024-05-20, 12:46pm

Really appreciate the info, thanks so much.