18" Butt

[Harry Worth]

Had a go at butting two 18" strips together. Darted around a fair bit to try and keep localised heating down plus periods waiting for it to cool down. I've used the pulse method from this site to join the strips together. My first attempts lacked penetration so I upped the power a bit. Managed to blow through a couple of times - my technique the problem not too much power I think. Any comments please. Had to photograph in strips due to its dimensions. Studying the picture I think I am being erratic with gas coverage - think I may be holding the torch at too much of an angle ot too far away to enable me to see the tip. I notice that the far left welds seem good.

 

[Harry Worth]

Looked again at the thin metal technique - should be weaving etc. Is a series of tacks OK on thin metal (if I manage penetration)?

 

[wyn]

Hello Harry,

Have you tried practicing on a bit of thicker steel to get the hang of torch position and travel speed etc.

The kemppi minarc 150 you have should be a good machine for thin stuff. You may be able to get away with short runs of an inch or so with the stepless controls you have on the welder.

 

[Harry Worth]

Thanks

Hi Wyn - I practised on the thin metal and I felt had reasonable success running a bead (eventually) - all down hill since then - I'm guessing that my angle is wrong because I'm trying to watch the weld puddle judging by the brown - Should I run a straight weld between the tacks or use a weaving or circular motion?

The welder controls appear simple with one for thickness. The second control my welder has puzzles me - arc length - I've stuck it in the middle of its travel and left it there. Chickenjohn has recommended I reduce my weld height but I'm not sure how I do that - do I work more quickly or does the angle make a difference to height? I'm using .8 wire- does .6 make a weld smaller? Or will the arc length make the weld smaller.

Off for a beer!

 

[wyn]

I would give it a go with a couple of straight runs to see how it goes.

With the setings ....set the thickness of the steel on the one dial.
The other dial adjusts the wire wire speed and amps. turn it towards the picture that shows the concave fillet weld (clockwise) and it will slow the wire feed and give you a flatter weld.
Turn it to the convex looking fillet weld (anticlockwise) and it will increase the wire speed.

This is pretty handy to fine tune the weld

I tend to write down the settings somewhere when you find a good setup so it can be used again.

With the wire size...i think they have produced the settings (material thickness) based on using 0.8 wire.

 

[Harry Worth]

I'll try the morning

Thanks again Wyn - That's really helpful info on that control - I felt I was pouring to much wire in.

 

[Chickenjohn]

Hello Harry, those butt welds are looking really good, decent penetration, nice bead height and most of the spot welds overlap. You can learn how to fill any little holes you accidentally blow whilst butt welding in with short pulses of weld, perhaps with a piece of copper clamped behind to absorb the heat. Don't worry about the occasional hole, it happens on thin material if the settings are hot enough for decent penetration.

I would keep practising on the thin ~1mm sheet. You won't be improving by practising on thicker stuff! Practise on what you want to use, which is thin.

It is fine to do lots of small overlapped spots on thin material, this butt weld looks good enough for a MOT worthy repair on the car! Actually would look very neat with a bit of dressing with the ginder and paint and seam sealer!

You can also try short beads between the tack welds, practise the weave technique for these. Also try 0.6mm wire as you said as this is better for thin sheet metal work.

Harry, you are almost there! Just need to get your aim a bit better and be butt welding consistently, try to develop a "feel" for welding.

A few more tips;
1. get your head and eyes as close as you can to the weld pool so you can see what you are doing.
2. If you are tending to blow holes, then just try just pulling the torch further away by a few mm rather than turning the power down. Tiny movements can make all the difference in welding. Hence the need to practise (A LOT), to get a feel for welding, make it instinctive.

Do please keep posting your practise pieces, I would say you are 90% there. I am impressed by how much you have improved!!!

 

[Harry Worth]

Thanks for the advise

Hi John - Many thanks for your comments- Only just spotted them - very helpful - I'll be back in the garage this weekend practising and trying to put then to good use.