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Jaay
11-24-2013, 11:22 AM
Hi all. Just sitting at work reading threads as you do. I was wondering what's the difference +/- between mig and tig welders/welding.

trikeman
11-24-2013, 11:30 AM
MIG is a form of arc welding, just like stick, except that it uses a wire that the machine feeds out with a motor instead of a rod controlled by your hand position, and you use an inert gas to shield the arc. TIG is more like oxy-acetylene welding, except you use a plasma arc created by a tungsten electrode held close to the base metal and shielded by an inert gas. Both TIG and oxy-acetylene require more hand-eye coordination, because you not only have to hold the torch close the metal but with the other hand you feed in the filler metal - like walking and chewing gum at the same time lol.

MIG is cheaper than TIG. TIG is generally cleaner and has less smoke and sparks. You can weld most metals with TIG simply by changing the rod you are feeding with your other hand. To paraphrase Dr. Pangloss, TIG is probably the best of all possible worlds, if you can afford it.

darnthedog
11-24-2013, 12:52 PM
The biggest + with Tig is the lack of splatter you get with Mig or stick welding thus your clean up is a whole lot less.
Gas shielding helps a ton on Mig and tig to reduce the splatter and smoke making a tons lot easier to see the puddle form. But Tig is a lot like soldering or sweating solder on cooper pipe in that you see the metal melt and can move on from there. The cost of Tig is more expensive. However with the set up you have, your half way there as you have the proper power source to build it into a scratch start Tig. See ChuckE2009 videos on the subject. The other plus with Tig is you can weld virtually anything providing you have the correct power source and filler rod. With mig your stuck with steel unless you purchase expensive spool gun to run aluminum wire. The Plus on Mig is you squeeze a trigger and the wire feeds the puddle. Thus it is easier to use as you have to only coordinate where to place the gun to feed the wire. There is fluxcore that does not use gas and gas shielded . The fluxcore while it does feed it smokes and spatters much like the stick welding. Where as the Gas shielded mig has far less smoke if any. Unfortunately a good breeze can keep you from welding. I'm a big fan of Tig but have yet to invest in the equipment to get it. Actually I did get a used Everlast micro 185. But it was busted up in shipping thus I had to return it. Unfortunately being used there has not been the opportunity yet to buy another. But it is on my wish list as the Mr Tig of Tig time and Jody of Welding tips and tricks have me excited to see how easy it really is to TIg weld. But as with Any time of welding it will take practice to make it look good. However I think Bill's brother became a believer in Tig when doing a bumper project with his Tig welder.
The biggest minus of Tig is it is much slower process then Mig or Stick. 4 inches a minus I believe I have heard on the videos. But as I won't spend 10 to 20 minutes of flap discing the splatter off it seem to be worth it time wise. Watch the Youtube video to form your own opinion of course. But I hope to have a Tig someday.

stormbird
11-24-2013, 02:53 PM
Hi there

I only do TIG & have only ever been a hobby welder.

Why ?

Well I like O/A welding that I did years ago , have lots of soldering experience and so are used to having a filler in one hand and a heat source in the other.


Good points

TIG is much cleaner
If the joint is a good fit you can weld without filler.
No smoke
Few sparks
Easier to weld thinner material
No cleanup for most joints , just run the grinder over any high spots if the joint is on show :joker:

Downside ?

The joints have to be very clean before you start.
Sometimes hard to get the gas lens into a corner
Need both hands supported if possible to aid accuracy.
Sitting down is preferred.
Lots of interruptions for sharpening Tungstens , however there are very few long welds when building a bike/trike so not to bad.
More consumables Tungstens/Pure Argon/filler/collets/lens etc

Is it harder ? maybe but then they are all hard when you have zero experience in the process ?

Some of my welds can be seen here :-

http://forum.atomiczombie.com/showthread.php/8210-Building-a-python-trike?highlight=

These are unground/cleaned up in anyway , 1.5mm sq tube + 3mm end plate.

FrankCrank
11-24-2013, 07:12 PM
....my preference is TIG, and in this part of the world it's very much affordable. If I was still in the UK, I suspect that would not be the case. Worth checking out availability and cost of argon where you live, as this may prove to be a show stopper.....

Tradetek
11-25-2013, 12:06 AM
I'd recommend wathcing video's on both processes and then deciding which one looks like it suits your personality better. That is what I did. After watching a bunch of videos I decided that TIG was much more in tune with my personality.

And yes, DTD has a very good memory... my brother came down a year or so back to work on some projects together. In the end he used my TIG welder for 95% of his bumper project because it was easier and ended up being faster with a LOT less cleanup. What little he did not use it for he ended up using the stick function of welder because they were spots that were to difficult to reach with the torch.

Bill

dmac257
11-25-2013, 12:25 AM
Good points

TIG is much cleaner
If the joint is a good fit you can weld without filler.
No smoke
Few sparks
Easier to weld thinner material
No cleanup for most joints , just run the grinder over any high spots if the joint is on show :joker:

Downside ?

The joints have to be very clean before you start.
Sometimes hard to get the gas lens into a corner
Need both hands supported if possible to aid accuracy.
Sitting down is preferred.
Lots of interruptions for sharpening Tungstens , however there are very few long welds when building a bike/trike so not to bad.
More consumables Tungstens/Pure Argon/filler/collets/lens etc

Is it harder ? maybe but then they are all hard when you have zero experience in the process ?



Can you weld indoors with shielded MIG or TIG? I don't have a garage and have put aside my build till next year. Since I am using flux core welder, I am limited to outside welding and need to spend almost an hour before I can do first weld weld, I was wondering if I get a small bottle and solid wire, can I weld in my basement? You said "no smoke" and "few sparks" and that sounds good to me. Is that for TIG only or will shielded MIG also be "no smoke" and "few sparks"?

Any thoughts
dmac257

go1000go
11-25-2013, 03:51 AM
Hi Paul aka Stormbird,
Just wondering what equipment you use for TIG, when I could not get my MIG to weld well, I considered it, still on the list, but not committing just yet, purely looking at this time. Also considering brazing to get to use thinner wall sections and lighter end product, but then I could also buy lighter wheels and components...

Thanks
Tim

stormbird
11-25-2013, 04:05 AM
dmac257

Actually it is the other way around , you always weld indoors if possible with TIG , otherwise the shielding gas can be blow away from the weld , this will seriously upset the TIG process leaving you with a badly burnt tungsten & a poor joint.

I cannot comment on MIG as I have not really done any only seen it being done in a college workshop [ where they also did stick ] of course it was set up with fume extractors , curtains etc.

Paul

stormbird
11-25-2013, 04:17 AM
Tim




Hi Paul aka Stormbird,
Just wondering what equipment you use for TIG, when I could not get my MIG to weld well, I considered it, still on the list, but not committing just yet, purely looking at this time. Also considering brazing to get to use thinner wall sections and lighter end product, but then I could also buy lighter wheels and components...

Thanks
Tim

I have a R-Tech DC inverter it was recommended on :-

http://www.mig-welding.co.uk/forum/index.php

One of the many Chinese inverter welders , 2 year warranty and HF start and some control over the pre/post gas flow and a few other settings I never touch :joker:

Even with my limited skills I can weld 1mm , the welder is also capable of Stick welding straight out the box very useful if the metal thickness goes above 3mm where you don't really need the finesse of TIG and the consumables are cheaper for stick.

You will be told by professional TIG guys that a TIG welder is rubbish if it does not have a foot control , well in their world where you are doing maybe stainless , really thin stuff or certified for aerospace that is probably true but hey these are only bicycles !

Whilst the MachineMart stick & MIG welders have a good reputation , when I looked at their TIG welders before I bough mine they were really Inverter Stick welders that you could buy a TIG torch for they had scratch start and no gas control at the torch end so at the time were best avoided.

The forum above has a good tutorial section and very helpful people , they have been helping me inprove the welds I have found hard to do properly i.e inside corners.

You , or anyone else for that matter , could always come over and have a go ?

stormbird
11-25-2013, 04:34 AM
Frank

I was lucky and found a guy less than 1/2 mile from me who can supply pure Argon , I paid a one off deposit on the bottle [ I get 90% back if I return it ] otherwise I give him 35 and get 200 lb of gas in a 10L [ IIRC ] bottle.

This is better in my view than paying a rental on a bottle that may sit for months not being used , as I don't build bikes all the time.

go1000go
11-25-2013, 06:00 AM
Thanks Paul for the info and most generous offer.
For the time being just researching.
Tim

darnthedog
11-25-2013, 09:03 AM
Can you weld indoors with shielded MIG or TIG? I don't have a garage and have put aside my build till next year. Since I am using flux core welder, I am limited to outside welding and need to spend almost an hour before I can do first weld weld, I was wondering if I get a small bottle and solid wire, can I weld in my basement? You said "no smoke" and "few sparks" and that sounds good to me. Is that for TIG only or will shielded MIG also be "no smoke" and "few sparks"?

Any thoughts
dmac257
Sorry dmac257
Inside is a relative term- the Tig appears to be safe to do indoors on a proper table- the gas shielded mig I would limit to someplace with cement flooring and a good table. Gas shielded mig is about 1/2 the spatter of fluxcore but it still spits little balls.
But gas shielded mig is 100% better when it comes to seeing the weld puddle as the flux is not smoking up to get in your way.
The big difference of the gas mig to tig is you are shoving metal into the weld puddle with Mig where as you feed the filler rod as it wants it with Tig. And that shoving on the Mig causes the splatter as you may be feeding a little too much or the puddle is not quite hot enough to add metal filler into it. In what ever the case the mig welding splatters. Gas has less and virtually no smoke. Hope that helps.

stormbird
11-25-2013, 09:17 AM
Hi all

I TIG weld ' indoors' in one half of a double brick garage , you can get the odd ' spits little balls ' with TIG usually if you meet some dirty metal or rust etc in the weld path.

However I see it as being so rare I stopped wearing my fireproof overalls and twice now I have had a senior moment and removed my welding mask and looked in horror as I had not removed the wife's car from the ' other' half of the garage and I was looking directly at the fuel filler door :surprised:

I generally leave the cars out about 1 hour afterwards as a precaution as there are always the odd oily rag about and blobs of grease which have the potential to smoulder unseen and burst into flames when your back is turned.

Modern man
11-25-2013, 09:29 AM
I think you also need to think about ventilation when you weld indoors, even a small fan to push the fumes away from you & one to exhaust to the outside (hang one in a window).

trikeman
11-25-2013, 01:14 PM
Speaking of cars and welding, I learned to move our cars well away from where I used to use my grinder in the driveway. Those of you who haven't done it yet, would be surprised at how much damage to the paint a few thousand tiny balls of molten metal (sparks) can do to a car finish even 10 feet away.

farst1
11-25-2013, 04:45 PM
TIG, tungsten inert gas. Pure argon. Most control over penertration.MIG, metallic inert gas. Pure argon. Invented as a way to weld aluminium. MAG, metallic active gas. Pure argon mixture with either oxygen and or carbon dioxide. Using an active gas with steel or stainless will dramatically reduce the amount of spatter.Only weld in a well ventilated area. MIG/MAG.MIG - aluminium welding, argon, u shaped rollers, nylon liner, aluminium contact tip(aluminium tips have a slightly larger hole and have an A stamped in front of the tip size. ie. A 0.8MAG - steel and stainless welding, argon mixture, v shaped rollers, spring type liner, regular contact tip.The only other difference is aluminium is up to 25% higher in ampsTIG. Aluminium, argon, AC, high frequency(impossible to strike an arc without), zirconiated tungsten. Steel and stainless, argon, DC, thoriated tungsten.

sandman
11-25-2013, 07:25 PM
I have not seen anti spatter spray mentioned yet, of course I may have missed a post !!!! with stick and MIG I always give the weld area a quick squirt( saves a lot of clean up) :cheesy: its also a good idea to give the MIG shroud a squirt too.
MIG outside has the same problems as TIG, lose the gas shield and you get a porous weld, welding a zinc plated bolt or part will cause porosity as well unless you remove the zinc coating and dont even think about welding galvanised metalthe fumes are not very nice.
A common problem seems to be blowing holes in 16swg with stick and MIG, I got round this when my mig only had 1.2mm wire was to pulse weld It had that feature but you can just keep flicking the trigger, the knack is to time the next trigger pull just as the last weld spot is still orange coloured but not molten or you risk cold start, with practice this can be done with some rods with a stick welder, stove piping is another way but I think beyond the realms of here.
Oh Paul, having a foot peddle,while handy, at the moment for me its just adding a third dimension to my Gerald Fordism with the TIG :jester:
regards
John

stormbird
11-26-2013, 03:03 AM
Hi Paul aka Stormbird,
Also considering brazing to get to use thinner wall sections and lighter end product, but then I could also buy lighter wheels and components...

Thanks
Tim

Tim

Forgot to say , Brads plans were not designed to be brazed [ unlike say the Recycled Recumbent of ADC ] so that is not really an option.

In particular you would have to sleeve any butt joints either internally or externally and the braze fillet needs to be 6 times the thickness of the metal being welded which can make ugly joints compared with welding unless the frame is designed from scratch to be brazed.

Don't get me wrong there are some beautiful brazed bikes out there but not built to Zombie plans.

stormbird
11-26-2013, 03:51 AM
Oh Paul, having a foot peddle,while handy, at the moment for me its just adding a third dimension to my Gerald Fordism with the TIG :jester:
regards
John

John

A true foot pedal [ like yours ] adjusts the current whilst welding but of course that almost always means welding sitting down.

My TIG is not capable of having a true foot pedal , however someone did make a simple on/off foot pedal to replace the switch on the torch.

I may do that for mine as I find quite often that I cannot get the torch comfortable in my hand because I cannot reach the torch switch.

darnthedog
11-26-2013, 10:20 AM
I have not seen anti spatter spray mentioned yet, of course I may have missed a post !!!! with stick and MIG I always give the weld area a quick squirt( saves a lot of clean up) :cheesy: its also a good idea to give the MIG shroud a squirt too.
MIG outside has the same problems as TIG, lose the gas shield and you get a porous weld, welding a zinc plated bolt or part will cause porosity as well unless you remove the zinc coating and dont even think about welding galvanised metalthe fumes are not very nice.
A common problem seems to be blowing holes in 16swg with stick and MIG, I got round this when my mig only had 1.2mm wire was to pulse weld It had that feature but you can just keep flicking the trigger, the knack is to time the next trigger pull just as the last weld spot is still orange coloured but not molten or you risk cold start, with practice this can be done with some rods with a stick welder, stove piping is another way but I think beyond the realms of here.
Oh Paul, having a foot peddle,while handy, at the moment for me its just adding a third dimension to my Gerald Fordism with the TIG :jester:
regards
John
John
Anti spatter spray has not been brought up because of the question of being able to bring the welding inside a building or home. While the anti spatter will make clean up easier the spattering still occurs. It just drops everywhere but the work. DMAC wants to weld inside his home during the winter. And was considering Gas shielded MIG in place of fluxcore to reduce smoke and spatter. And while it will reduce the smoke and some spatter it does not eliminate it all together. Where as with Tig there is nearly no visible smoke and I have not seen spatter at all during the Youtube videos tutorials.
Jaay wanted to know the +/- of Tig verse Mig.

trikeman
11-26-2013, 10:58 AM
My house is a wood framed structure. So, I don't have a basement with nice concrete walls and floor.,I don't even like to weld in my garage, lest a stray spark burn the place down. I've considered throwing those welding blankets they sell over everything, but still I'd worry. I have also considered that concrete board you put under tile floors up the walls in a room off my garage. So far, I just keep it outside.

sandman
11-26-2013, 03:48 PM
John

A true foot pedal [ like yours ] adjusts the current whilst welding but of course that almost always means welding sitting down.

My TIG is not capable of having a true foot pedal , however someone did make a simple on/off foot pedal to replace the switch on the torch.

I may do that for mine as I find quite often that I cannot get the torch comfortable in my hand because I cannot reach the torch switch.

I think Paul, you have hit the nail on the head there, you cant do a good weld whatever method you use if your not comfortable, sitting or standing.always worth taking time to dry run the move, well thats my opinion as a Welshman that hates rugby and cant sing :jester:


regards
John

FrankCrank
11-26-2013, 10:14 PM
....I like the idea of a pseudo foot pedal, couple of times recently I was welding and thought it would be good to have a foot operated on-off switch. Was looking at getting an R-Tech TIG box a while back, the website said something about main circuit board from Europe (Italy?), rest from China, and assembled and testing in Europe I think, or something like that? Anyways, bought one locally in the end....