# Thoughts on single-stage vs two-stage regulators for brazing?



## golden boy (Oct 29, 2008)

I need to complete my brazing setup and I'm stuck on a decision regarding regulators. I'd like to buy them (along with tanks) from my LWS, but I've been pricing them online to get an idea of the cost. Looks to me like two-stage are about triple the price for a comparable single-stage. Yowza! I know Doug Fattic prefers two-stage for a steady flame but allows that single-stage will save you lots of money.

Anyone care to chime in? I'm a "buy once, buy well" kind of person, so I'd rather not buy single-stage now, only to realize in a couple months that I'm not happy with them.


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## golden boy (Oct 29, 2008)

I'll add that I'm "braze-only" at this point, no TIG, so all of my tube joins will be brazed. If I just needed regulators for braze-ons, I'd probably just stick with single-stage.


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## toby_g (Jul 29, 2008)

The only _real_ difference I have found between the 2 is when your bottle is running low; with 2 stage it keeps the pressure you want better, with a single stage you will need to keep checking the pressure, and adjust accordingly. When your bottle is full, there is no _real_ difference.

others may disagree, but I find I can do everything I need for brazing (Fillet, lugs, braze-ons) with a single stage regulator, 2-stage gives no real benefit.


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## Live Wire (Aug 27, 2007)

I've used nothing but single stage regs and never had a problem, the few times I've worked in another shop that had two stage regs I didn't notice any differences.


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## golden boy (Oct 29, 2008)

Thanks, guys. I'm probably over-thinking this. I have a tendency to do that. I'm sure I'll be just fine with the single-stage. Time to get regulators and tanks and start brazing!


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## doug fattic (Mar 11, 2010)

I'm a professional that uses my brazing equipment frequently. Spending a couple of hundred dollars extra to get the best quality on one of my primary tools that I use all the time only makes sense to me. I'm not a hobbyist trying to keep all costs within a tight budget. More importantly I'm teaching students how to braze – which for many is tougher than they were expecting – and I don't want even a slight flame disturbance ever to be an extra burden in their learning curve. 

Over the years I've used a number of different regulators with different size diagrams and that had either one or two stages. All of them work okay but not exactly the same. Conventional wisdom says the only time you can tell the difference between one and two stages is when the tanks get low. However in my own experience I haven't found all regulators be equal. For example when I was using decent Smith smaller diameter diaphragm one stage regulars I'd have to make minor adjustments to the flame from time to time. I never have to do that with my big diaphragm Victor 450 two stage regulators. Those slight adjustments may not be important for many but they matter to me. I love the fact that they give me a constant steady frame always. No other regulators have worked as well as those under all conditions. Their extra cost is worth it to me. 

So my advice is that if one's budget only allows for single stage regulators, get as big a diaphragm as possible. They size of the diaphragm has an impact on flame steadiness. They will work fine. It is possible that if you are like me and are sensitive to small changes you will prefer two stage regulators. Like many things in life our purchase decisions depends on available finances. I should add that for propane the regulators don't seem to make as much difference as with acetylene.


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## G-reg (Jan 12, 2004)

Now that the Guru has enlightened us all....No really, that's the only NON-sarcastic thing I've said today. Look at the paragraphs above and soak it up.

Now my hobbyist/hack opinion. My torch is on and off many times during a build. I'm striving for a tack then full fillet braze sequence, but that's hard and I suck. And days go by between attempts at competent welding. So I am not sensitive enough to realize the difference, and have my small tanks on and off so often the benefit of low tank stabilty is lost on me. I nearly set up from step one for a neutral flame every time I light the torch. 

If it's between buying proper tools and eating, you probably can lose some weight anyway. But for a hack newbie you likely don't have the slightest idea that your flame is variable with the tank level. I'll admit to running either/or gas dry, only noticing when the flame gets cold or starts spewing carbon.

If you've got the cash, a good torch, Kevlar lines, 2 stage regs, and big tanks will make the learning curve flatter. That said, the easiest way isn't always the best way to learn. I (want to) think there's a lot learned in fighting with Harbour Freight quality equipment. I'm about to braze my first frame with a nice torch/lines. I don't have much time with the new toys, but in the bit of screwing around I've done I think the Kevlar hoses are the biggest bang for the buck on budget O/A setups. That cheap hose is heavy as hell, and makes it tough to build the instinctual movement necessary for proper heat management.


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## golden boy (Oct 29, 2008)

Thanks Doug and G-reg. Doug, when you talk about diaphragm size, does that correspond in any way to the duty level of the regulator? Victor classifies theirs as light/medium/high/extra-high duty level. What does this mean? I'm having trouble understanding the relationship between the components in an OA setup. For example: I bought the Victor J-28 torch. Victor rates it as light duty. Does this mean that I should pair it with a light duty regulator for best results? And what about the relationship between regulator duty level and tank size? Is there any? I'd really like to understand this so I can make a well-informed purchasing decision.

So far I have the Victor J-28 torch, #0 tip and lightweight hoses from Tinman Technologies as recommended by Dave Bohm. So I'm looking for appropriate regulators and tanks to complete this setup.


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## golden boy (Oct 29, 2008)

Bump...see my post above. Any advice on "right-sizing" my remaining brazing setup?


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## unterhausen (Sep 28, 2008)

I think they are talking about the flow rates. I have heard that you can rebuild the higher flow rate regulators to flow less gas, but I have no idea what they do for that. I bought some Victor regulators, and they weren't cheap, but I'm not a big fan. Not sure what to do to get better regulators than that.


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## doug fattic (Mar 11, 2010)

You can use any regulator with the J-28 torch. You can also use any standard regulator with any tank size (as long as the fittings match). You can tell what the approximate diaphragm diameter is by measuring across regulator. The bigger the better (and the cost goes up too). For oxygen it is better to have the unit that only regulates up to 40 psi (since you would never go that high) than one at 100 or 150 (since anything above 20 is useless for our purposes anyway). That way you can get finer control. 

Your choice of diaphragm size and how many stages will be dependent on your allowable budget. They will all work. Some will last longer than others and have steadier flames. As a teacher I know that it is easier for students to learn on better rather than cheaper brazing equipment.


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## golden boy (Oct 29, 2008)

Thanks again, Doug!


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## FTMN (May 10, 2010)

Golden Boy - you mention tank size, and I noticed none of the more experienced folks have chimed in. If you are planning on getting fairly small tanks (my acetylene is a B sized tank), you might want to do a little research...

Did you look to see if Victor has a tank size recommendation based on your tip size? Smith has a table that lists all the acceptable tip sizes for a particular tank size (acceptable meaning that it doesn't exceed the 1/7th Rule under normal use). Although I've also read that the 1/7th Rule has been changed to the 1/10th Rule in some circles.

Not sure if everyone's set up is like this, but my oxygen tank is quite a bit smaller than the acetylene, which is fine because the O2 is filled to a much higher pressure.

This is coming from a fellow newb, so hopefully some more experienced builders will chime in.


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## golden boy (Oct 29, 2008)

I bought a Victor 460 acetylene regulator (two-stage) on eBay today. There are a handful of 450 oxygen regs on eBay too, so hopefully I'll be getting one of those soon too. I think this means I'll have to buy larger tanks, but that's fine. For someone who generally dislikes driving, the fewer the trips to the LWS the better.

Thanks for everyone's input.


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## A. Spence (Sep 25, 2009)

All the two stage reg's I've seen (not that I've looked all that closely) seem to be rated for pretty high output pressures (like 5 - 200 psi). That makes sense, since they're rated as heavy duty and guys in industry will be using them for running large rosebud and cutting tips and the like.

Seems like for framebuilding a two stage regulator with a low pressure output (say 2 - 50 psi) would be more useful. Does such a thing exist?

I have a single stage oxygen regulator that outputs 2- 40 psi, but I took my existing higher output regulator and had it modified locally to get it to do that. I do find the ability to accurately dial in a low pressure to be quite handy, so I'm wondering what is available regulator wise that is calibrated for lower pressures, without having to be modified?

Alistair.



Alistair.


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## doug fattic (Mar 11, 2010)

Victor 2 stage regulators, the VTS-250 and the VTS-450 each have 4 different models with various pressure ranges labeled A, B, C and D. The range of the A (which is what I have) is 2 to 15 PSI. The B model's range is 2-40. The C and D start at 5. So you want to look for a VTS-250 A or a VTS-450 A. The Bs work fine too. Actually all of them work but just don't have as fine of control.


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## calstar (Mar 26, 2013)

What if you just replaced the regulator torch gauge with a 2-15 or 2-40? I realize the standard reg is designed for 100psi and up, but at least you wouldn't have to look squinty eyed to see if you were on 3 or 4psi. Any safety issues?

thanks, Brian


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## golden boy (Oct 29, 2008)

I just keep learning! Thanks for the additional info, Doug. By luck, the 460 acetylene reg I bought on eBay is the "A" model. Thanks to your post, I just bought a 250A oxygen reg on eBay. Just need my tanks now.


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## A. Spence (Sep 25, 2009)

calstar said:


> What if you just replaced the regulator torch gauge with a 2-15 or 2-40? I realize the standard reg is designed for 100psi and up, but at least you wouldn't have to look squinty eyed to see if you were on 3 or 4psi. Any safety issues?
> 
> thanks, Brian


I don't think it's quite that simple. I had a local regulator repair shop modify my oxygen regulator some years back to read lower pressures, but I can't remember now what exactly they did to achieve that. They did replace the torch side pressure gauge of course, but I'm pretty sure they switched out some internal parts too, the diaphragm spring I think but like I said, I don't exactly recall.

Alistair.


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## golden boy (Oct 29, 2008)

*Simple swap-out?*

I received the oxygen regulator I bought on eBay:









As seen in the photo, it came with a barbed connector for the hose. My hose has an 'A' threaded connector with a 'B' threaded adaptor option. Is this a simple matter of unscrewing the barbed connector and replacing it with the proper threaded connector? Or do I need a different regulator?


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## doug fattic (Mar 11, 2010)

You can buy the proper B fitting (or A) at your local welding supply store (or they can order one). It can be swapped out without problems. Of course if you had a hose you didn't care about, you could just cut the fitting off and jam the bare end of the hose onto the barb and clamp it with a radiator clamp. This would allow you to start brazing right away. Rubber fuel hoses come in various diameters and it would need to fit the barb. In other words measure the hose first to make sure it would fit the barb.


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## golden boy (Oct 29, 2008)

Thanks Doug. It seemed pretty obvious that I could just replace the barb with a threaded fitting, but thought I'd ask since we have this amazing forum. I'll buy the proper fitting. Don't want to cut my brand new TM Tech lightweight hose.


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## unterhausen (Sep 28, 2008)

I am not a big fan of my LWS (same "I see ****" treatment as you get when you go into a random LBS, weird huh?), but they have an infinite number of fittings. If I walked in there with that regulator, I would walk out with the proper fitting on it in about 5 minutes.


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