SteveWallace
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| posted on 21/8/14 at 09:52 PM |
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What MIG Welder
I've now started to strip down the 1949 MG TC that I bought as a project car to do a complete nut and bolt restoration. The chassis is sound
but, not unsurprisingly, some of the body panels (e.g. wheel arches, bottom of door skins etc) will need to have bits cut out and repaired where they
have rusted through. This is an example from the front wing...
 
Description
They are all thin mild steel bolt on parts (door skins are almost tin can thin, over a wooden frame) and are not structural safety elements as they
would be in a modern monocoque car, so I'm planning on doing the repairs myself as butt welds for a neat invisible finish when ground down and
painted.
I've never welded before, so I have two questions
I) what welder should I buy. I assume that its MIG, but can I get away with a cheap gasless one, or do I need to invest in quality for this level of
work?
ii) How hard is it to learn (bearing in mind I'm not going near safety critical items such as the chassis)? Will I get there just looking at
YouTube and practicing on lots of scraps, or should I be looking for a course (and if so, anyone know of a good one in the Nottingham/Derby area).
I'm not after a formal qualification, just getting good enough to do what I need to.
Looking forward to learning a new skill as well as saving money by doing it myself.
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Mr C
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| posted on 21/8/14 at 10:23 PM |
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Speaking from being in exactly the same place as you at the beginning of the year. Check out MIG welding forum for specific advice, about starting
out, machines etc. I even posted piccies of my welding to get feedback, though like all forums you need to weigh up the advice offered.
It really is a black art with so many variables and a small window in which to hit the sweet spot Buy the best machine you can afford,bearing in mind
if you go cheap you are likely to struggle more to learn and upgrade sooner rather than later. I bought an ESAB caddy which is a top spec machine
which is easy to set up.
Also buy a decent helmet, there's nothing worse than not being able to see!! I've tried a couple and settled for a sealey PWH620 which is
auto darkening and has more variable darkness settings than most helmets retail price is around £100 but you can get it closer to £70 if you shop
around.
It's difficult and frustrating to learn on your own a course was advised for me which I haven't done yet but will do at some stage. I can
stitch metal together now but its not the prettiest at times and I usually end up grinding quite a few welds down. As mentioned there's so many
variables, metal thickness, amps and wire speed being the obvious. Others include the different types of joint, butt, tee, lap, corner and edge joint.
Edges are less tolerent to heat than flat surfaces or corners. Oh and the orientation of the joint can also play a part,..vertical, horizontal upside
down etc..then there's torch speed..
In terms of metal thickness, the thicker the easier, body panels are quite tricky, easy to blow holes in the metal and distort panels with too much
heat. A friend of mine restores MG's for a living, he tacks the panels on then gradually stitches the panel in by doing short bursts of welding
in small stages across the join, allowing it to cool down, eventually joining up the welds into one continuous seam.
Hope I haven't put you off, just wanted to make sure you went into this with your eyes wide open, it really is a difficult skill to do well,
those that do make it look so easy. That said when you do get a good weld done it's so satisfying. All the best with it.
Mike
[Edited on 21/8/14 by Mr C]
[Edited on 21/8/14 by Mr C]
Girl walks into a bar and asks for a double entendre, so the barman gave her one
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nick205
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| posted on 21/8/14 at 10:26 PM |
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In my limited experience gas will be easier to master and to achieve reasonable results. I've recently embarked on the same task with a 205 gti
and have been using a Clarke 151te welder. It's a hobby machine running of a standard 13A socket. I converted to a rent free Argon gas bottle
as the disposable type that come with the machine run out fast and with out expensive.
There are some excellent YouTube videos on welding sheet metal using the pulse technique. It takes a lot of practice, but seems the best way of
reducing heat distortion and now through in the thin metal.
HTH
ETA
would echo the above on getting an auto darkening helmet, pretty much essential IMHO, £50 one from Tool station works fine for me. Proper gauntlets
are also essential and not expensive.
[Edited on 21/8/14 by nick205]
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Oldaker
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| posted on 22/8/14 at 07:06 AM |
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I would also suggest using gas mig, not gasless. From what I have seen, gasless is not so clean. I always use co2/argon mix which gives a lovely
clean neat weld.
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andrew.carwithen
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| posted on 22/8/14 at 07:26 AM |
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I've just bought a Clarke 160TM which is basically the same spec as the 151TE but iuses the large bottles and comes with a regulator to suit.So
probably ends up being a little cheaper than having to convert the 151TE. Sign up to machine mart's emailing list and you should get an invite
to their vat free days which will save you a further 20%!
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Slimy38
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| posted on 22/8/14 at 09:10 AM |
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You should also consider that welding kit is a good investment, if you go for Clarke or other known brands you can usually sell it on for a high
percentage of the purchase price. So yes there may be a fair bit of money tied up in one, but you'll get most of it back. Engine hoists seem
similarly high valued.
And I agree with others, go for gas with an argon/co2 mix from one of the rent free suppliers (hobbyweld for example). Don't do disposable, I
worked out you get about thirty seconds of gas at a decent flow, which won't even give you enough time to practice.
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DIY Si
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| posted on 22/8/14 at 08:28 PM |
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Don't be afraid to buy a second hand machine. I spent £250 IIRC on my Migatronic Automig. It's a great big, but old now, industrial
machine that needs a 16A supply. It's a good way of getting a better grade of machine than I could otherwise afford, and if you buy carefully
you can get a little used machine. Mine needed a new rotary switch which was all of £1.50 from Maplins to be as good as new. And I'd suggest you
steer of gasless. A good bottle of Co2/Argon will make a lot of difference to the ease with which you can weld.
The main thing to look out for with a MIG welder for bodywork is not the high end of the power output, but the lower end. The lower it goes, the less
likely you are to distort anything. 25A on the low end is good and what mine goes to. I can weld thin sheet with no bother now I'm used to
it.
One other thing: practice, practice, practice. Never start on the car until you can do the work without making yourself even more work! It's
time consuming and a little annoying at times, but as someone who jumped in a bit early I can really advise you to not touch the car until you can
weld thin sheet with little to no distortion.
“Let your plans be dark and as impenetratable as night, and when you move, fall like a thunderbolt.”
Sun Tzu, The Art of War
My new blog: http://spritecave.blogspot.co.uk/
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19sac65
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| posted on 22/8/14 at 09:37 PM |
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+ 1 for a good quality used one
I bought a snap on turbo 130,fan cooled so doesnt cut out after 10 mins use
Give a nice even weld and very reliable
Also sold under the Cebora name
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brum_gustavo
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| posted on 23/8/14 at 07:19 AM |
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Welding thin steel with acetylene is quite easy, but warpage is a risk. Mig, on the other hand, will demand quite a bit of practice until you can
spot-weld, but practice a lot first. I´ve welded with a gasless Mig, it is a bit tricky but once you master it the welds are pretty good. Since they
will be ground later, their less than perfect appearance is not a problem. Another advantage of gasless mig is that you don´t have the risk of
running out of gas on a saturday afternoon, ruining your welding weekend. But as everyone said, welding takes practice, whatever method you choose.
Good luck!
Build diary: http://gustavobrum.wordpress.com/
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SteveWallace
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| posted on 23/8/14 at 09:38 AM |
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Thanks for the advice guys. To summarise...
On balance I should go for gas rather than gasless MIG as its easier to get right. Gas source should be decent size rent free cylinders rather, than
small disposable ones. I should go for as decent a quality as I can afford, possibly second hand as long as I know what I am looking for, and it
should have a power setting that's low enough not to blow holes in thin panels. Needless to say, good quality PPE is essential.
I'm going to need to practice a hell of a lot on scrap of the same thickness as the panels that I need to do on the car.
Sounds quite daunting, but I like a challenge. At least I'll be able have every bit that I need to repair on the bench, so I don't need
to worry about having to learn how to do it whilst lying on my back under the car.
Christmas is coming, so the mask and gloves could well find their way onto my list for Santa.
I looked into courses in the Nottingham/Derby area and the only evening courses that I can find are quite long and expensive and lead to a formal
qualification, which is a bit over the top for what I need. The course tutor did apparently used to run a four week, two evening per week DIY course
so I may contact him to see if he's planning on doing it again.
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IanSouthLincs
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| posted on 23/8/14 at 11:18 AM |
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Get a half decent machine and you'll be amazed at how much you use it! How much do you want to spend is my first question, a good machine is
definitely an investment and can last a lifetime, but in reality, along with all the add on costs, such as PPE that has already been mentioned, you
really need to put a price on it. Also worth considering is your electricity supply, do you want to run off a standard 13 amp supply or do you have
16/32 amp at your disposal? 150 amp mig is going to be your maximum power from a 13 amp plug, so it's pointless going for any more if this is
your supply limit. Incidentally the Clarke 150/151/160 models all state 16 amp power supply, however many (including me) do successfully run them off
standard power supply.
In a nutshell if you're buying new and you have #650+ to throw at a machine, the world is your oyster (Portamig 215 would be my choice!).
However if you're looking around #300-#400 you won't go far wrong with a Clarke, especially on a VAT free day from Machine Mart. There is
a guy on the mig welding forum called Weldequip, I can recommend him, he's a good knowledgable guy to deal with with very reasonable prices
too.
As mentioned above Argon/CO2 will give cleaner welds, however gas is really only suitable for indoor use, possibly outdoor on a still day with wind
breaks up, as your shielding gas will just blow away. I went for the Clarke EN160 which is dual purpose gas/gasless, I have a full size Argoshield
Light bottle from BOC gases on the Volkszone deal (loads cheaper!) and a proper regulator. I went for dual purpose for the only reason that if I need
to repair a gate at the bottom of the drive I can just wheel it down there, reverse the polarity, stick gasless flux cored wire in it and away you
go.
Hope this hasn't completely confused you, go for it, you won't believe you were ever without a welder!
Edited to add: Please do not be tempted to buy one of the cheap Chinese things advertised just about everywhere, they will be more of a hindrance,
minimum ampage will be too high (blow holes in everything) and duty cycle will be too low! Other than that they'll be fine!!
[Edited on 23/8/14 by IanSouthLincs]
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britishtrident
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| posted on 23/8/14 at 11:36 AM |
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Clarke good
SIP s***
[Edited on 23/8/14 by britishtrident]
[I] “ What use our work, Bennet, if we cannot care for those we love? .”
― From BBC TV/Amazon's Ripper Street.
[/I]
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r1_pete
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| posted on 23/8/14 at 12:06 PM |
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Go for a machine which will go down to 25 amps, better still 20, but, this is where they get expensive, 30 amps is a touch too much for bodywork.
Also invest in a joggler, if you set the edge of the existing panel with the joggler, you will only be welding to the edge of your new metal, you can
cut back the set edge so you are not creating multiple layers.
Where you can't joggle the edge and need to butt weld, clamp a piece aluminium sheet, 2 or 3 mm thick behind the joint to soak some heat away.
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blakep82
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| posted on 23/8/14 at 12:10 PM |
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For body work, your looking about 30 amp, so your minimum should be down there.
Clarke is good for the £3-400 range, if you've got a bit more to spend (and personally I would) I like Esab. My next welder will be an esab
machine. I really want an origo mag c251. Lot of money though.
How about the caddy mig c160? http://weldsafelimited.co.uk/welding-equipment/mig-machines/caddymig-c160i
Good quality machines. BAE systems use Esab machines
Another option, TIG?
Takes longer than mig, but better control of the weld, half the gas flow of mig, so gas use on longer welding time isnt really an issue.
DC for steel
AC/DC machines if you want to weld aluminium (a lot more expensive)
Wider current range, eg https://www.weldequip.com/pro-tig-180.htm , 10-180A, compared to a similarly priced clarke mig at 30-150A
Just to clarify, use sheild gas! My first one was a gasless only machine. Horrible and messy, and left a weld full of holes
________________________
IVA manual link http://www.businesslink.gov.uk/bdotg/action/detail?type=RESOURCES&itemId=1081997083
don't write OT on a new thread title, you're creating the topic, everything you write is very much ON topic!
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coozer
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| posted on 23/8/14 at 03:56 PM |
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Go over to the mig weld forum and seek out weldaquip.
I got a 185amp portamig off him and have fabbed a chassis, welded up Suzuki Sj chocolate panels and rust holes in the chassis legs on my old 106.
Built all sorts of other stuff, stands, brackets, engine crane, press frame, it goes on and on..
I was very impressed with how easy this was as after messing about with a 150 Clarke thing was convinced mig welding body panels was impossible!
Its a quality machine with automatic wire feed, takes a full 25kg roll of wire and a full size gas bottle, euro type torch. Does need a 16amp blue
outlet but that's just a spur off the wiring in the garage and runs my welder, compressor and wood saw. All the electrical parts are cheap
enough from tool station.
The other plus is after hours and hours and years of use I'm still on the original tip, shroud, liner etc. The euro spec torch is top quality.
When the shroud gets blocked just pull it off, tap it on the ground and all the spatter falls off!
Steve
1972 V8 Jago
1980 Z750
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SteveWallace
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| posted on 21/11/14 at 05:36 PM |
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OK, so its now time for me to buy myself a MIG welder for a Christmas present.
I was thinking of going for the Clarke MIG 90EN welder. It only goes up to 90amps, but the advantage for me is that its the only one that I can see
in the range that goes down to 24amps. The main reason for buying it will be to restore the MG TC. Some of the panels are very thin, so I think that
I really do need 24amps rather than 30. i.e. I'm more bothered about the low end than the high end. It can also be used gas or gasless.
Its a very reasonable price (which is another attraction) and if I ever decide that I need something more chunky then I'll sell this one second
hand and upgrade.
Has anyone got any experience of using this and have I missed something obvious that means its the wrong choice?
[Edited on 21/11/14 by SteveWallace]
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perksy
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| posted on 21/11/14 at 07:47 PM |
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Some good advice above and Clarke make some very decent mig welders.
Personally i'd always go for one of their 'Turbo' variants that has a fan to give you longer duty cycles.
With regards technique, It really is practice practice practice and if you are going to attempt to weld thin material or material that is perhaps
rusty and not sound you will need a lot of patience.
It would be worth checking with your local technical college and seeing if they do a night course in welding or if they would possibly set something
up for you just in mig welding technique, they might offer a few hours with one of the lecturers or let you into one of their current courses just
concerning mig welding ? (worth an ask, you never know)
I did a classic car restoration course at our local college and its one of the most enjoyable courses i've ever done.
[Edited on 21/11/14 by perksy]
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