Test Piece

[Onoff]

I'm determined to get the hang of this MIG lark primarily for car body repairs. God knows I've tried and it's more miss than hit!

This is my planned test piece. A lump of 1mm steel that I've cut into with 0.8mm disc. I can mark up which area had which settings on to gauge my progress.

It'll be 0.6mm mild steel wire, CO2/Argon mix and my Clarke 130TE.

I assume I should clean this steel up first, both sides?

Guess no need to de-burr the underside, I meant I couldn't on a car...

Sound like a plan?

 

[Onoff]

Definitely run a flap disk over that! Needs to be clean for a good weld.

use a on/off stitching technique on that steel and your welds should be ok.

Ta. Flap disc both sides or not?

 

[roofman]

Save a few for vertical and overhead..stuff you will encounter welding vehicles

 

[Craig-SM]

On cars you’ll only be able to clean up the exterior so just flap the outside.

With thin metal use the minimum power settings and use the wire speed to get a better penetration. Instead of running a bead of weld just do series of 3 to 4 spot welds to stitch together then move to the other side so you don’t build up too much heat and warp the metal. If you have an airline use that to cool it

 

[slim_boy_fat]

move to the other side

errr....end ?

 

[TechWise]

Much easier to clean it up with the flap disc before you cut it into all those wee bits. Speaking from experience

 

[Onoff]

Might sound the daftest question but what grade flap disc is best, 40, 60, 80?

Saying that all mine are worn!

 

[slim_boy_fat]

I'd go with 80 [or whichever you have most of ], you're not looking necessarily for a mirror finish - just clean metal.

 

[tom2207]

80 is grand , but dont clean it back to immaculate , as its not what you will find on a car ,, have a play with a backe too , lump of copper , in case you can get in behind some of it ,, or flatten a copper pipe and use it as you can feed it in from some where ,,, all tricks you will pick up as you practice ..
try a tack at half the gap then half the half , and half the gaps etc , . sops the sides from walking away from each other ,, tack a bit of tin across the gaps too ,, as if you were matching the surfaces on a patch repair , theres hours of fun and frustration to be had .
most of all , dont be afraid to burn through a few , to find where the limits are ,,, try beating a few tacks flat as you go ,
but most of all enjoy it ,,, and stop for a cup of tea and a hob nob to let things cool down , both the steel and you .

 

[tom2207]

ps ,, very tidy job there cutting the slots to practice , nicer than some of my patches ,,,

 

[Onoff]

Comments please!

Cleaned up the steel one side with a scotch pad in the cordless drill:

1mm steel .0.6mm wire and tip. CO2/Argon mix.

Gas regulator was set on 4. These are the machine settings:

I started bottom right. Did a few spots together with a pause inbetween, letting the weld dull. Then moved to the other end of the cut slot. The test sheet started to distort so I blobbed the middle of each slot to stop it from going out of level.

Moving right to left I tried on those middle runs to make the next weld before the first had cooled.

I always pushed.

This is the rear side.

Thoughts welcome.

 

[Craig-SM]

Well you managed to warp the metal, that’s from too much heat so you need to allow it to cool more before welding again.
penetration is good, maybe wind the speed down a touch.
Each spot weld should just overlap the previous one slightly so you end up with with no gaps. If 3-4 is too much heat then just do 2-3. I find it easier if you put the nozzle at 45 degrees to the piece and the wire a bit longer when doing spot welds as you can clearly see where spot will be and ensure the overlap

 

[Onoff]

Just playing a bit more.

Upping from 2 to 3 on the Y wire setting and I was blowing thru:

Upping the speed to 6, still with Y on 3 and it was even worse:

Dropping Y back to 2 and the speed on 5.5 I feel is my best yet:

Penetration the other side:

Just for fun I tried some vertical up. Starting on the right. One go was maybe not too bad?

Then I burnt through my gas tube. Shortened it no problem, then it ran out!

 

[tom2207]

your going well ,,, but did you enjoy it , and are you keen for more

 

[Onoff]

your going well ,,, but did you enjoy it , and are you keen for more

Thoroughly enjoyed it tbh. Need some more gas for a start. Might get a bottle of Hobbyweld 5.

And some more steel to practice on perhaps unless I clean this up a re-slit it?

Above the centerline is all my vertical up attempts. Wasn't really concentrating with a lot of that...

Bottom left the "best"?

Someone elsewhere suggested I might do better with 0.8mm wire?

 

[Onoff]

I'm thinking I'm limited on settings with this old welder? Presumably with a modern, inverter mig you can just turn a dial to set the amps?

 

[tom2207]

try 0.8 , it gives you a whole new set of variables to play with ,, personally i use 1mm on cars.

 

[Onoff]

try 0.8 , it gives you a whole new set of variables to play with ,, personally i use 1mm on cars.

This machine will only do 0.6 or 0.8.

How will 0.8mm give more variables?

On the subject of 0.8mm wire I've killed all the 0.8mm tips I had trying to weld stainless. I assume I can just drill out a 0.6 with a 0.8mm drill?

 

[tom2207]

This machine will only do 0.6 or 0.8.

How will 0.8mm give more variables?

On the subject of 0.8mm wire I've killed all the 0.8mm tips I had trying to weld stainless. I assume I can just drill out a 0.6 with a 0.8mm drill?

once you change one thing all sorts of things change ,, thats how the world works ,, yep you could drill out tips , but its a pita , try a gas nozzle cleaner / reamer through and see how that goes , I just keep lots in with the wire in the welders I use , and a few shrouds etc , than they are there ,, a spare swan neck can be handy too.

 

[Craig-SM]

Power on minimum was fine before and 5.5 speed was better but try 4.5 and allow it to penetrate longer.
The disposable bottles are expensive and inconsistent. A hobby bootle and regulator seems expensive but it will pay for itself in no time and the welds will be consistent too. Get a peashooter to measure the gas flow at the nozzle.