Having Problems Oxy Acetylene Welding

[culp]

Hi,

I bought some basic Murex Oxy Acetylene equipment recently and I'm having a few problems with it. I'm not an expert, I did some classes at a local technical college but the teacher set up the gear for me and It was all top-end professional stuff. Once I got going I enjoyed the welding.

Here's the details

• I am welding car thickness steel, 0.9 mm (approx)
• I'm using a #1 nozzle
• The Murex Documentation recommends a pressure of 0.14 bar for both gasses
• The gauge on the regulator for my oxygen tank wont go that low! its lowest tick on the gauge is 1 bar not 0.14
• with a bit of fiddling about I think I'm getting 0.5 Bar. On the acetylene tank I can set things more accurately so I have matched the 0.5 bar on that one too
• The metal is not melting at these pressures it gets to about yellow hot but there's no weld pool that to me seems to suggest not enough gas pressure?
• Could it be the nozzle? Do I need to go to a bigger nozzle?
  
  This is really frustrating I have some floor panels I need to weld up, my Mig set is busted and I cant afford a new one and I can't get on with Oxy Acetylene

 

[weldequip]

Change the nozzle to a No.2 with a couple of Psi pressure setting on each gas. Make sure the gas is flowing ie.with the valves on the torch open when you set the pressures.
weldequip

 

[culp]

Many thanks

Change the nozzle to a No.2 with a couple of Psi pressure setting on each gas. Make sure the gas is flowing ie.with the valves on the torch open when you set the pressures.
weldequip

Aah right I give that a whirl.

 

[pedrobedro]

I use a No2 as said above and I turn on the acetylene cylinder, open the valve on the torch then turn the acetylene regulator in till I have gas to light it then turn the reg more till I get the flame with no soot. Now open the oxygen valve and repeat the regulator turning till you get a nice neutral flame. You might have to experiment a bit as it blows out if you turn too quickly but when you get the hang of it it becomes second nature, it depends on how sensitive your valves are. Get a good fire watcher for when you are under the car.

 

[piman]

Hello Culp,

are you sure your gauges are in Bar as psi is more usual with gas sets?

it should be quite easy to set to about 2 psi or so?

I normally use a No. 1 nozzle (BOC Saphire welding torch) on 20 gauge steel, about 0.8mm I think?

Alec

 

[culp]

Thanks

Thanks for the advice everybody I'm getting there

 

[Cruiser]

Hi
If you are still have problem to use your torch, I recomend you set the presure in the tanks a little more than you need. The important thing is you regulate the pressure of the gas in the torch seeing the shape of the flame recomend to each number of nozzle, in fact, the form is similar in all numbers of tips, is only the size that change.
Good Luck

 

[smc]

If you do as pedrobedro says then you will end up with the correct flow settings for the nozzle size. If you change nozzle size repeat and no matter size of new nozzle the flow will be correct.

 

[runnach]

I reckon OP will be out of gas if he reads last two replies

 

[chunkolini]

I can remember this situation, did my night class and loved it.
gt the kit and went round the bend trying to get it working consistently.

Patience and time are the best way, I can just remember my oxygen having a much coarser gauge, ie bigger increments than the acetylene one. I usually use a no3 or5 nozzle on 5psi and have no problems. But I can remember almost throwing the whole lot in the canal and giving up.

Stick at old bean.

Chunko'.

 

[campervan]

what i do

hi all before i get told off for working dangerously i am sort of self taught
and i use to set me oxy gauge(regulator) on 10 and 5 on me acc, turn on the acc tourch light it and get the flame till soot just goes then turn the oxygen till the flame was small in the nozell more acc and ox if i wanted a biger flame ect might even be 20 and ten just know where to put the dial they show the volume of gas and presure with flow valves fitted
its only since joining this site i have a better understanding of oxyacc but still stick with what i have done for the last 20 years

 

[Adam_R]

Hi,

I bought some basic Murex Oxy Acetylene equipment recently and I'm having a few problems with it. I'm not an expert, I did some classes at a local technical college but the teacher set up the gear for me and It was all top-end professional stuff. Once I got going I enjoyed the welding.

Here's the details

• I am welding car thickness steel, 0.9 mm (approx)
• I'm using a #1 nozzle
• The Murex Documentation recommends a pressure of 0.14 bar for both gasses
• The gauge on the regulator for my oxygen tank wont go that low! its lowest tick on the gauge is 1 bar not 0.14
• with a bit of fiddling about I think I'm getting 0.5 Bar. On the acetylene tank I can set things more accurately so I have matched the 0.5 bar on that one too
• The metal is not melting at these pressures it gets to about yellow hot but there's no weld pool that to me seems to suggest not enough gas pressure?
• Could it be the nozzle? Do I need to go to a bigger nozzle?
  
  This is really frustrating I have some floor panels I need to weld up, my Mig set is busted and I cant afford a new one and I can't get on with Oxy Acetylene

funnily enough i just had the exact same problem today, have ordered a no2 and 3 nozzle as they are quite cheap at cromwells.
ill let you know how i get on tommorow

 

[Bsmith]

I reckon OP will be out of gas if he reads last two replies

Uhu....... or spending so much time watching a flame that he gets nothing else done.

 

[piman]

Hello Adam, Culp,


I don't know what sort of regulator\gauges you have but mine start at 1 lb per sq inch. I normally run about 2 lb and have no problem welding 20 gauge steel with a number 1 nozzle. which is normal body thickness on the cars I work on. Structural sections I would use a 2 or 3. Certainly, doing a panel butt weld, a 2 is too big.

Alec

 

[Chickenjohn]

I think the problem is not enough gas flow, you might be misreading the gauge, or possibly the nozzle is blocked.

Acetylene needs to be set to about 20l/min and the same with oxygen. Then open the acetylene tap on the torch first, light it and set the flame to about 1 foot (half a meter if you are Euro). Adjust the flame so that the end of the flame is "feathering", then open the oxygen very carefully till the blue bit of the flame shrinks to about 1/8- 1/4 inch.

I would not use no 2 nozzle as said above, the flame will be too hot and you will either blow holes or distort the panel. Use a no 1 nozzle for car panel body work of around 1mm. Maybe the nozzle is blocked or danaged- buy a new no1 or clean it if you can.

Dont forget to use a shallow angle between torch and work, butt up accurately for minimal filler wire use and wiggle the torch once the steel has melted.

Oxy Acet gas welding is lovely to do and unbeatable for car body panel work, far superior over mig!

I have done quite a bit of gas welding over the past four years, it is a lovely technique!

 

[Adam_R]

well guys today i picked up my nozzles and theres a big bit of difference its a bit hotter as expected which suits my working speed a bit more.
i also tried a bit more gas and its also helped alot ill be having a fair bit of practice today before i tackle the car (1979 mini) with a bit of luck most of the welding will be done by the weekend.

cheers for all the advice

 

[piman]

Hello Chickenjohn,

"Oxy Acet gas welding is lovely to do and unbeatable for car body panel work, far superior over mig!"

I'm glad to see someone else who appreciates this. MIG seems to have taken over as the be all and end all for car restoration, and I have great difficulty in convincing others about this.

Alec

 

[brightspark]

Hello Chickenjohn,

"Oxy Acet gas welding is lovely to do and unbeatable for car body panel work, far superior over mig!"

I'm glad to see someone else who appreciates this. MIG seems to have taken over as the be all and end all for car restoration, and I have great difficulty in convincing others about this.

Alec

u dont have to convince me ive had bottles for the last 30 years . its not as fast granted but with proficiency not much slower .and disimlar metal thickneses can easily be welded without blowing holes and resetting dials and switches to suit one setting suits all when started

 

[Chickenjohn]

Hello Chickenjohn,

"Oxy Acet gas welding is lovely to do and unbeatable for car body panel work, far superior over mig!"

I'm glad to see someone else who appreciates this. MIG seems to have taken over as the be all and end all for car restoration, and I have great difficulty in convincing others about this.

Alec

Fortunately, I've been on a vehicle restoration course! Learnt the joys of gas welding there and I love it! It leaves the steel nice and soft so it can be planished and shaped and with gas you can shrink areas. gas does take more skill, but the results are well worth it, no grinding needed if the repair piece and panel were butted up perfectly!

I am a bit of a fan of old school techniques, I also like lead loading and using cellulose paint!

 

[Adam_R]

just thought id update this
yesterday i tried again with more gas and a No:1 nozzle works a treat and ive been practicing alot to get ready for the actual car which should be happening at some point today