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View Full Version : Please give me advice on Oxy Acetylene Welding and Brazing



RideHard
11-23-2012, 11:44 AM
Atomic Zombie builders,

Please give me some advice on Oxy Acetylene equipment for brazing and welding. I know that there are modern and quicker ways of fusing metal, but I've become enamored by this form of welding. It seems a bit more arty, and I'm one to get caught up in such things. I've read about the dangers and such, so please let's not hamper on that.


What I need is advice on equipment: What torch brands are best for purchasing a new torch & regulator? What are some good brands to look for on the used market? Are the vintage torches all hype or are they a good purchase? How much will it cost to have an old torch rebuilt? Are those small Oxygen and Acetylene tanks a bargain or are they garbage? What about brazing with propane-- Is it safer than using acetylene? Is brazing strong enough for a heavy person to use for the type of frame building we will use here?



I saw a pretty good deal on craigslist for a Harris Torch and Smith Regulators for only $60. Are these the type of deals that I should look out for? I'm willing to shop the used market and piece together everything.

Here are the model numbers:
Oxy Model 1910F-540
Acetylene 1194E-510
Harris Torch Model 62-3



About safety: What do I need and what should I look out for?


Training: I'm signing up for an OV welding class and my local vocational college & I have the Wall Mountain Oxy Acetylene Welding DVD with Steve Bleile.


Thank you.

Ibedayank
11-23-2012, 12:13 PM
try WWW.WeldingWeb.com

personally I would not be comfortable buying an AO setup used as you do not know
how it was taken care of. Way to many reasons for me to want something i KNOW will work properly an not turn into a flame thrower or blow me into the next county. You can get NEW setups minus tanks for under $300

richl
11-23-2012, 12:22 PM
When I used to restore cars a few decades ago, I used to do a bunch of oxy/ace welding. Get a cart :). I forgot where I got my torches, I would imagine I found the cheapest used kit I could find, they lasted me many years before I needed to replace parts. If you want to be safe you could bring in your torches and gauges to the tank supplier/filler and see if they have any recommendations for you (are they safe, and will they work type stuff).

I will agree with you on the "art" of them, I think some of my best work was done back than with nothing more than some torches and a couple of tanks :)

YMMV.

Rcih

trikeman
11-23-2012, 02:50 PM
I dont have time to write up all the whys at the moment, but that torch is way too big for what you want for bike work. I'm sure I have written it up several times on the old forum, and I will give you some more later. In a nutshell, most guys buying torches today want a big torch so that they can flow a lot of gas to cut thick steel. To braze or weld on bicycles or airplane frames you want a much smaller torch, such as a Smith AW1A or similar. I have two of those with a large assortment of tips and they are great. They are lighter and easier to handle, and much easier on the expensive gas.

If I were looking for an inexpensive torch to learn on today, I would be tempted by the HF torch kit that FreddyTK has reviewed on YT (http://www.youtube.com/watch?v=brhsHH_yqHk). Still larger than you need, but pretty flexible and CHEAP

My favorite torch is my Henrob, (Now the dhc2000), but I would never pay what they want for one new. I got a killer deal on mine from Craigslist, but I waited a long time. Here is is beside a Tomahawk rear end I was welding with it.

http://www.flickr.com/photos/smyrna5/sets/72157626869134423/

river
11-23-2012, 03:28 PM
When I first started Welding I used gas and I brazed. Then i started welding and I used it for a long time. Bought a tank and regular and gauge setup. IT can get very expensive with buying gas. I got small tanks and that was a mistake. Kept running out. If you get that type of welder make sure you get larger tanks. More expensive but allot cheaper in the long run. I then graduated to a stick welder which worked out well on heaver stuff but was tricky with thinner stuff. Then i got my mig set up and i just love it. Cheaper to run and easier to use. With a torch there's always a fire hazard and its easier to burn your self or just start a fire. Its easier to warp something too, I still have mine but i haven't used it in years. I guess it just a progression of things. You need to find someone with one and try it out to see if it is your cup of tea before you invest your hard earned cash. Its great for art work but my preference is mig with gas or a tig i love to have but my mig is here and i dont really need to spend that cash, there expensive but there the best

richl
11-23-2012, 04:17 PM
I bought a dvd some years ago some guy in England made, he did all his work restoring old classic cars with hand tools and a set of torches. Bunch of different hammers and different blocks and molds and he could make just about anything. I thought his torches were a bit larger than the ones posted in Trikemans HF video, but than again, this guy was pretty good, and he probably needed the larger torches for the surface area he sometimes worked in. If I can find the darn thing, I saw it a couple of weeks back I'll try to find some of his videos from YouTube, his torch work is pretty impressive, makes it look way to easy.

Ignoring my moment of sentimentality :) River's advise is probably the sound way to go though :) Though, the price of those HF torches are tempting :)

Rich

FlatBlack
11-23-2012, 08:23 PM
I'm not aware of brazing with propane, but have heard about brazing with Mapp gas. I have tried it a few times, but found the temps marginal and the flame too broad to be a good alternative to oxy/acetylene. Others may disagree.

If you are using sleeved joinery with lots of surface area, I think that brazing is an option for building bikes. If you are using fishmouth joints, I think it best to weld.

I agree with Trikeman that with regard to torch size, small is better and I agree with River that with bottles, bigger is better. Not sure if they still make it, but I have a Smith Cavalier torch which is small and light and I like it fine. Many of my aviation friends are all aflutter over the Meco torch. This is a teeny tiny torch that's available from TM Technologies (link below).

These days, I probably use my tig more often, but the utility of gas welding and brazing for the thin stuff we work with, makes an oxy/acetylene rig still something special. Like you, I am enamored with the process.


Cheers,
Bill


http://www.tinmantech.com/html/meco_midget_torch.php

darnthedog
11-23-2012, 09:10 PM
A warning for Gas bottles- Most Gas suppliers lease the bottles with gas in them and may give you issues with used gas bottles. I know that in USA they have to be tested every 7 years before they can be refilled. This can be an expensive process. The lease is a one time up front fee and when getting more bottles you just exchange without releasing the bottles. So you only pay for the gas and not the bottle lease when exchanging them.
So do not purchase gas bottles. Just buy your torches and hoses regulators. Save to Gas bottles for Gas supplier. Recently had a co-worker tell me how he felt shafted from buying used gas bottles for that reason. They were expired bottles that were nearly full when he bought them with torches but when he went to refill them the Gas company refused them as they had expired testing dates. So he ended up leasing new bottles. Also When transporting Acetylene- If you lay the bottle on its side for transport- do not try to use it for a couple hours after turning it upright. The Acetylene is a liquid and has to settle before it will flow from the tank correctly. Otherwise it spits fluid and clogs torch nozzles I have been taught by welding instructors. You can confirm that with your gas supplier. The frames on these bicycle have to be welded not brazed. I have never had any luck with Mapp gas in Brazing. It will solder very well when working with plumbing. But is would not get hot enough for Brazing for me. Have fun and be safe.

trikeman
11-23-2012, 09:34 PM
I bought a dvd some years ago some guy in England made, he did all his work restoring old classic cars with hand tools and a set of torches. Bunch of different hammers and different blocks and molds and he could make just about anything. I thought his torches were a bit larger than the ones posted in Trikemans HF video, but than again, this guy was pretty good, and he probably needed the larger torches for the surface area he sometimes worked in. If I can find the darn thing, I saw it a couple of weeks back I'll try to find some of his videos from YouTube, his torch work is pretty impressive, makes it look way to easy.

Ignoring my moment of sentimentality :) River's advise is probably the sound way to go though :) Though, the price of those HF torches are tempting :)

Rich

The Tinman (https://www.tinmantech.com/)does whole car bodies and uses torches smaller than mine (mostly the Meco Midget). I wouldn't use a small torch for anything over about 3/16" thick though. I have a bunch of his aluminum and metal working videos and they are great, but I got them for nearly nothing when he was closing out his VHS stock .

When I weld 16ga 1.5" tubing with the my little Henrob, I use either the smallest tip I have or the next one up. Even with that you have to pay attention to not burn through.

river
11-23-2012, 09:39 PM
I lease my bottle now too. been doing that for ten years just pay for the gas and no hydro charges

trikeman
11-23-2012, 09:42 PM
I also agree that you save money with the bigger bottles. I have pretty large ones that I bought used, but you have to be careful with used tanks, since most gas suppliers won't fill the large tanks unless they have no gas company names stamped on them or you have some sort of solid receipt to prove you bought them. When I bought mine, the guy told me they were empty, but I got them home and it turns out they were both full. That was 4 or 5 years ago, and they still have a lot of gas in them. I don't weld much though. They probably won't hassle me with the Acetylene bottle, since its only about 3 feet high, but the oxy bottle about twice as big and I expect to get turned down if I use up the oxy before I die lol. My O2 bottle has the name of a company stamped on its neck that went out of business decades ago, but they probably still wont fill it and I am sure it will be out of certification by then.

As Darnthedog said, Brads designs are made to be welded, and not brazed, but you can get around that with careful joint design and makeshift lugs etc.

trikeman
11-23-2012, 10:18 PM
The Henrob tips and the small Smith AW1 tips I generally use to build bikes consume about 2-6 cubic feet per hour, depending on which size I am using. Its basically a pin hole with 4 psi of pressure behind it. I can spend hours setting up a weld, then a few minutes actually welding on a bike frame. If you add up all the inches of weld on a zombie frame, it probably comes out to less than a few feet total. With appropriately sized tips, a 200 cubic foot tank lasts a long time, if you only build a handful of frames a year.

You can download the entire Smith catalog here. Take a look at some of the smaller torches in there, as well as the capacity and gas consumption of the smaller tips.

http://www.smithequipment.com/products.htm

Petone_NZ
11-24-2012, 01:16 AM
I too have a Henrob torch and am happy with it. No particular plans to go looking for an electric welder unless a great deal jumps out at me.

The two bikes I've written up here were both done with the Henrob, and a couple more in the works:
- http://forum.atomiczombie.com/showthread.php/6214-Custom-fitted-bike-for-little-person
- http://forum.atomiczombie.com/showthread.php/6377-Dutch-pattern-freight-bike

Unrelated: it can take me a year or two to build a bike (including breaks ... this is why I don't write them up until they're finished.

Regards, Neville

RideHard
11-24-2012, 09:54 PM
I was looking at a much larger Harris outfit, but it seems that a smaller torch will work better.

How do the Henrob 2000, the Smith AW1A, and the Meco Midget Torch compare. It seems that the Henrob would be the easiest to learn on.

My plan is to piece meal my rig together together. I could make this a lot easier by just buying a used $70 arc welder on craigslist. I guess I have to waste money somewhere!

trikeman
11-25-2012, 08:22 AM
I've never used the Meco Midget, so I can't really comment on it, except to say that if the Tinman likes it, it must be good. I have a friend on one of the welding forums that welds aircraft frames all day. In his opinion the Henrob can't do anything that any good small low pressure "aircraft" (like the Meco or Smith AW1A) can't, and both are lighter than the Henrob. As I said earlier, if I hadn't found a used Henrob for really cheap, I would have never bought one new. The Henrob's pistol grip is kind of cool, but it can also be awkward in some situations.

The Meco and the Smith AW1A are similar in price for the torch body. The Meco tips may be a bit cheaper now and the Tinman offers good support on them. My only concern with the Meco is that it puts your hands a little closer to the weld and these welds do get hot. Smith used to sell a nice kit (the Cavalier that someone already mentioned) with the AW1A body and a nice tip selection. Now they mostly market the Aw1A bundled with tanks etc (the VersaTorch) as an Heating/AC tool for brazing and soldering pipes, (http://www.smithequipment.com/products/pdfpages2012/page10.pdf) because gas welding is becoming a lost art. It has little screw on tips, like the Meco, but you can always use regular AW1A tips.

trikeman
11-25-2012, 08:37 AM
My plan is to piece meal my rig together together. I could make this a lot easier by just buying a used $70 arc welder on craigslist. I guess I have to waste money somewhere!

No question that you can get an arc welding rig much cheaper than an oxy-acetylene set up. I just don't enjoy them (or MIGs either) as much. If it were me, I would rather buy a good used arc welder, such as a Lincoln tombstone or Miller, than a cheap new one from HF or similar. You can usually buy the AC only Lincolns or even a Miller Thunderbolt(what Brad uses) off eBay for around $100-$200. Its easier to weld with DC, so its better if you can find a used AC/DC model. I paid $200 for my Craigslist Miller Thunderbolt AC/DC model 5 or so years ago. They are built like tanks, but test it before you buy, because things can go wrong with them. I ended up having to replace a burnt out diode (part of the DC section) in mine.

FlatBlack
11-25-2012, 09:00 AM
Several reviews of the meco torch on the link that I provided earlier. Some compare it's performance to other torches that users have owned.

Cheers,
Bill

RideHard
11-25-2012, 10:44 AM
I've decided to go with the Smith AW1A. I will get the torch handle and the tips I will use the most first. I will then add regulators, hoses and I'll probably lease some tanks.

bambuko
11-27-2012, 12:43 PM
I'm not aware of brazing with propane...

For many of us (this side of the pond) oxy-propane is the only sensible option for brazing (no good for welding though). BOC who have monopoly on the supply of acetylene are pricing diy types out of the market by making rental charges daylight robbery.
It is not as good as oxy-acetylene and uses much more of the oxygen, but... oxygen bottles are available non-rental and propane is easy to get anywhere.
For those in UK, try:
http://www.weldequip.com/oxy-propane-brazing.htm

Chris

FlatBlack
11-27-2012, 01:09 PM
Thank you Chris. Do you also have experiance brazing with Mapp gas or the Mapp gas substitutes?

Cheers,
Bill

bambuko
11-27-2012, 01:40 PM
No Bill,
Although Mapp (I understand) gives slightly higher flame than oxy-propane, the latter is high enough for the job so there is no real advantage, particularly when you bear in mind that Mapp is only available in disposable bottles (afaik) making it very expensive proposal again.
My only experience so far is silver brazing using Sievert type propane torches, but this is not really good enough for bicycle frames, so I have just purchased proper bronze brazing kit (Sometimes confusingly and erroneously referred to as "bronze welding - there is no fusion so it is definitely no welding. It is a lot better described as fillet brazing).
My first job (after few test pieces) will be bottom bracket assembly :rolleyes4:

How about this for an inspiration:
http://ryan.flickerbikes.com/archives/202

Chris

bambuko
12-12-2012, 07:11 AM
...My first job (after few test pieces) will be bottom bracket assembly :rolleyes4:


This is a clamp which will secure bottom bracket to the main boom of my Voyager:

https://lh4.googleusercontent.com/-b7ZWefoxehY/UMhyDpSNk7I/AAAAAAAAM68/cMQBSvuZpMc/s800/IMG_6451.jpg

Not pretty :cheesy: but I am sure perfectly functional.
I found brazing slower and easier to control than MIG welding.
Must keep practising to make it look better...

Chris