Not so hard.
1156 forum posts
Decided it was high time that I gave the TIG feature on my CT-312 machine a try as it would be needed to do repairs on the bodywork of my '35 Austin Seven.
Spent yesterday messing up pieces of 1.9mm MS and was pleasantly surprised at how easy it was. Can hear people shouting at the screen in disagreement.
OK I did have to regrind the electrode tip a number of times, but that appears to be quite normal for newbies.
I do however, need to do a lot more practice as the last time I did any O/A welding was in the '80s.
My gas welding experience has most definitely helped me as muscle memory allowes me to keep the electrode at a constant distance, sort off, and feeding the filler rod at the same time.
If anyone has any tips, they would be appreciated.
TIG Welding Album added.
Geoff - Google time for TIG techniques
Edit: Austin Seven bodywork is from 1.2mm to 2mm thick.
Edited By OuBallie on 23/04/2015 10:40:15
|Jesse Hancock 1||23/04/2015 10:44:44|
|314 forum posts|
In my opinion mig is cake on a plate mate. Set point squirt. Just make sure you're well out of any breezes and haven't been on the beer. Yes I do realise your talking TIG but I've far more expertise on MIG.
One problem however is the cost of hiring bottles and buying gas.
Edited By Jesse Hancock 1 on 23/04/2015 10:45:19
Edited By Jesse Hancock 1 on 23/04/2015 10:54:07
|3447 forum posts|
Adams Gas do an interesting range of gases where you only pay once for th bottle!
|andrew winks||23/04/2015 11:52:41|
117 forum posts
I purchased an inverter stick welder with TIG function 5 yrs ago, finally got around to trying the TIG as I wanted it mainly for stainless work. I believe I am a oxy acetylene and stick welder master but TIG has bettered me! Maintaining a correct arc with one hand and using the filler rod with the other has frustrated no end. Some advice taken on is that forget the filler rod until you master maintaining the arc. I have the greatest admiration for those using AC gear and foot pedal control fabricating complex ally bull bars and similar items. I guess it's like all else, practice, practice. Cheers, Andrew
|Speedy Builder5||23/04/2015 11:55:58|
|2454 forum posts|
40 years ago, I replaced the "bottom half" of my 1932 A7 using an Oxford welder with a single carbon brazing attachment. The joints were made similar to TIG, using a single carbon to make the 'weld puddle' and filling with a special phosphorous bronze filler rod. The joint could be made on rusty metal as the rust 'burnt' away and the puddle of steel was ready for the bronze (No flux or gas needed). I guess the effectiveness of the weld is that I have never seen a crack in the 100s of joints I made with the setup. (Not to be confused with twin carbon brazing). However all the joints were real hard and had to be fettled with an angle grinder. Today, I would have used MIG, as others say, point and squirt. The biggest problem is limiting the effective heated area to minimise distortion.
1156 forum posts
Your's is a little older than mine - nice!
Need to decide whether to do a paint job or just remove the horrid overpaint, but need to do some rubbing down first.
I will be starting a Thread on the Friends forum once I get going on the Ruby.
Interesting about your brazing as I have both of those accessories but not tried them yet, so will have to give them a go soon.
Did a fair bit of brazing on my racing car using O/A back then.
Considered gas welding but the USERY cost/price in the UK killed that idea.
Been reading and looking at videos, but the old adage 'Practice makes perfect' applies here.
Geoff - TIG practice after a sarnie and coffee.
|Jesse Hancock 1||23/04/2015 13:30:28|
|314 forum posts|
Good luck Geoff. (not sarcasm)
Speedy : I love the Austin it even goes with the house.
2904 forum posts
If you've got the TIG set up, just use it for TIG brazing - far easier and more controllable than carbon arc brazing. Get some Sifsilcopper rods and save a lot of hassle.
TIG welding is my favourite welding process but it's not a panacea - just try welding a couple of copper (plumbing) pipes together.....
Murray - in Kunshan, China.
|169 forum posts|
Looks good Geoff, I've been using TIG on an amature basis for 20 years ish, I've had a bit of training from my mate who's a coded welder, you know the sort, can pick up any welder and weld any clean bit of metal while making it look easy and the finish is beautiful. Unfortunately my welding isn't close to his but it ok.
You need a pair of thin TIG gloves and I use my little finger to give me stability, the gloves stop you getting burnt while doing this. I presume your using an automatic head shield, if not get one.
The great thing about TIG is you get very good penetration and a lot of control over the weld, I've welded M6 stainless nuts onto stainless plate with a tiny barely visible bead at the join, try that with an arc or MIG.
|Bob Brown 1||23/04/2015 16:26:26|
1021 forum posts
Be aware the TIG arc will burn any exposed skin so gloves are a must and do your shirt up. Also as with most welding the work must be clean and free from rust and other crud. My TIG set is a big 3 phase 375amp AC/DC unit with foot pedal and water cooled torch, the foot pedal is really useful as it allows you to back the power down once the weld pool has formed, takes a bit of getting used to but saves blowing holes all over the place.
|"Bill Hancox"||23/04/2015 16:27:07|
257 forum posts
I use mostly MIG. The constant distance and steady hand are becoming ever more difficult to achieve with each passing year. I have considered building something like these **LINK** to support my hand and provide a smooth lateral movement when clamped to my welding table.
1.2 - 2 mm of steel in body metal. Little wonder they lasted so long.
|Nick Hughes||23/04/2015 18:00:23|
256 forum posts
Lots of helpful people (for all types of welding) on this site:- **LINK**
1827 forum posts
Keep practising on thin plate. Don't try copper yet as it requires a great deal more control, but overall you have certainly started in the right way. Don't believe all that you hear about mig being very easy either. Its easy to spurt a weld down and make something stick but start welding up a steam boiler and you suddenly realise its a bit more complicated than it might appear!. Good luck by the way.
|norm norton||24/04/2015 10:37:19|
|164 forum posts|
Geoff - Like you I wanted to build a smidgeon of ability with TIG. For me it all goes well down to 1mm thickness then you need to start using heat sinks to stop the holes! My limit was 0.7mm thick stainless, and that was not pretty. I then wanted to repair rusty motorcycle mudguards and just failed using TIG. But, I went back to the cheaper MIG and was able to fill holes, build seams and so on. Several hours later with the grinder and the mudguards were strong and ready for the filling/painting stage.
Muzzer - thanks for the TIG-Sifsilcopper suggestion, I was unaware of that. I had read that TIG-Sifbronze did not work. Sifbronze is actually BRASS (copper/zinc) so a very confusing trade label. But the copper braze might be ideal for repairing rusty cars?
|Jesse Hancock 1||24/04/2015 11:12:51|
|314 forum posts|
I will hold my hand up and say, you are right Fizzy. There are draw backs with all welding techniques.
Someone mentioned heat and buckling which on a car body may well be a significant factor. On the chassis less so. I renewed the spring hanger box section on a mark two Jaguar with 3mm plate which when finished rang like an anvil. Try that on a modern motor.
To retain the said optimum height for a mig isn't too easy as the umbilical cable is heavy after a while so I used a two handed pistol grip (lower hand setting the height) and where I could hung the cable over my shoulder.
Like any advice on here it may work for one but not the next.
2904 forum posts
Norm - it's a lot more controllable and clean than carbon arc. For one thing you don't need to apply flux or buy flux coated brazing rods and there's little cleaning up required. You can also control the arc easily with a TIG machine, especially if you have a foot pedal or torch-mounted control.
Here's a flange plate I brazed to the bottom of an old fuel tank. I would have struggled to weld that. I needed a thick plate so that I had a flat surface for the fuel pump gasket and I needed to join that to the thin tank which was also partly rusted. The gap filling capability was quite impressive and handy!
As you say, it's essentially copper with a trace of silicon. The term "brazing" can be applied to almost any copper alloy filler IIC.
|219 forum posts|
Murray, Which gas did you use with the TiG brazing?
|Bob Brown 1||24/04/2015 12:08:49|
1021 forum posts
With foot pedal control the upper power limit can be pre set and as you weld the power can be reduced it also works well at the start as more power is required initially to get the weld pool but less once welding and if more power is needed it is easy to increase the power. Welding in difficult positions means it is not always possible to use foot control and in some cases you may find it is next to impossible to get the TIG torch in and still feed the filler rod.
1156 forum posts
Thanks for all the comments, suggestions and encouragements, much appreciated
I do have all the safety gear, TIG gloves and auto helmet, plus I only wear cotton, no nylon in sight.
I cringe every time I watch a video on MMA/TIG/MIG and see the guys are virtually in their 'birthday suites'.
Murry, thanks for the advise on brazing. The perfect solution sometimes. What size rod, electrode and amps did you use?
Second day practice on TIG was a disaster as stupid me I kept trying with a 1.6mm electrode on a 40amp setting and spent more time regrinding the electrode tip than doing anything else, so in future, will use higher amps as I started with till I feel comfortable.
Gave up in disgust and did some work on the Seven which calmed me down somewhat, except for the ^%# different head sizes on the 5/16" BSF bolts used to secure the bulkhead/footwell panels.
Bill, your link gives me 'Server not found' error message on my iPad. Is your devise a little frame made from round bar?
Geoff - Carport roof leak back
2904 forum posts
I forget what electrode and current I used but looking at the pic, it was on the high range (up to around 300A), although I don't know what the actual max current setting (set by the big knob) was. You make sure the arc is landing in the copper not the steel and turn the current up and down to control the size of the pool. I don't recall the rod size but I suspect the smaller 1.2mm would be the safest choice.
Generally you only use pure argon in TIG welding. MIG uses an argon and CO2 mixture for steels (in which case technically it should be called MAG ie metal active gas).
I suspect that ideally for TIG brazing you'd use a mixture of argon and up to 10% hydrogen which would give a reducing atmosphere, turning any oxides to water vapour and giving a "bright" finish. Most of the industrial gas suppliers keep Ar/H mixtures but you need to be a serious trade customer to get it. At that concentration it is considered non combustible but still providing a useful reducing effect.
In the old days, you would use hydrogen for induction brazing, or possibly water gas. Not something I'd want to mess about with although it never seemed to be a big concern.
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