Welding 5mm SS rod

[David Pye]

Hi guys,

I've moved on from burning lumps of aluminium

Current project is trying to weld a frame of 5mm steel rod to hold some plastic containers.

I'm having problems trying to figure out how best to do this - The joints are mostly right angles (two pieces of 5mm round cross-sectoin rod at right angles, ground to 45 degree faces so they butt up nicely). Not having much luck trying to weld them 'freehand' so was wondering if the best way to do it is to tack, rotate the frame, tack, and so on, rather than try to weld it in one go.

I'm sure the problem presently is the arc gap being far too large, as the whole thing ends up glowing red hot, and with a lot of soot!

Any suggestions on current would be welcome as well - I was trying around 30 amps.

Cheers,

David

 

[GrahamGKD]

Hi David,
Is it 'stainless' steel (as suggested in your title)?

I've done quite a bit of TIGing 5mm 316l SS rod - I find it comes out OK but unfortunately I can't remember the settings I was using - sorry - nothing fancy though just plain DCEN TIG! What happens if you turn the current down a bit - do you not get enough heat then? I think I was using a fairly small tungsten (1.6 - I think I tried 1.0 and then went back to 1.6) The stuff I was doing lent itself to be laid down on a slab of copper to get some of the heat away. Can you clamp yours together with a piece of copper backing? While I was getting used to it I did melt the whole thing a few times! I didn't go for any fancy fit up - just butted or crossed the pieces and filled the join in with the filler rod. I get discoloration but no soot - cleans up well.

If you continue to struggle I'll get set up again and see what settings I am using.

 

[langy]

When i've done 3mm to 3mm on custom grilles i use a 1mm tungsten sharpened to a long point, I fuse it, can't tell you amps as i use a pedal.

 

[David Pye]

Thanks for the reply guys.

I've been having a play with things again this evening, and I think I've concluded I need more general tig practice laying beads and simple welds etc before I go too far with any project, even something I thought would be fairly simple!

For example, I can lay a reasonable multicoloured autologous bead on stainless, but it has a much blacker sootier appearance when trying add 316Lfiller rod, for reasons I don't (yet) fully understand!

Cheers again,

David

 

[GrahamGKD]

Hi David,
Is your filler rod nice and clean and are you keeping the hot end of it within the protection of the gas envelope?

 

[David Pye]

Hi Graham,

Yep, the filler rod is fresh out of the pack - I've not specifically cleaned it, but wiping it down with a paper towel soaked in meths gets nothing off it.

I am using a gas lens with a size 7 ceramic, and am probably actually keeping the rod TOO close to the arc if anything, as it does sometimes ball back before reaching the pool. I am trying to modify my technique to keep the rod a bit lower to make sure it melts into the pool rather than by the arc.

I've tried a couple of 'spot welds' to see if I can melt some filler rod into a static pool without the sootiness, but it still seems to be there! A little puzzled if I am honest. Will try with a larger ceramic maybe to make sure. (Running argon at about 8lpm).

Cheers,

David

 

[langy]

Are you using 1mm rods, to be honest on 3 or 5mm rods i don't use any rod.
I use 5lpm with a gas lense with a 1mm 2% thoirated tungsten.

Hi Graham,

Yep, the filler rod is fresh out of the pack - I've not specifically cleaned it, but wiping it down with a paper towel soaked in meths gets nothing off it.

I am using a gas lens with a size 7 ceramic, and am probably actually keeping the rod TOO close to the arc if anything, as it does sometimes ball back before reaching the pool. I am trying to modify my technique to keep the rod a bit lower to make sure it melts into the pool rather than by the arc.

I've tried a couple of 'spot welds' to see if I can melt some filler rod into a static pool without the sootiness, but it still seems to be there! A little puzzled if I am honest. Will try with a larger ceramic maybe to make sure. (Running argon at about 8lpm).

Cheers,

David

 

[GrahamGKD]

I'm out of ideas I'm afraid – everything you mention sounds OK. I'm certainly no expert on this stuff though but I have achieved reasonable results with a similar set up. I presume the tungsten is not getting contaminated by having the filler too close - does the arc remain stable throughout - no variation or change in colour? I had a look at the Miller TIG manual trouble shooting section - it mentions gas flow rate, cup size and post flow in connection with soot.

 

[David Pye]

Made a few adjustments to technique and things seem to be going better. I guess it is just 'teach yourself TIG welding' teething troubles!

I think part of the problem is that the rod was melting by the arc, rather than into the pool, but that seems to be behaving itself a bit more!

Once I am having better luck on sheet, I will come back to the SS rod!

Cheers guys!

 

[langy]

Thin rod isn't the easiest thing to do really, I asked if you were using 1mm tungstens but you havn't answered ???

Made a few adjustments to technique and things seem to be going better. I guess it is just 'teach yourself TIG welding' teething troubles!

I think part of the problem is that the rod was melting by the arc, rather than into the pool, but that seems to be behaving itself a bit more!

Once I am having better luck on sheet, I will come back to the SS rod!

Cheers guys!

 

[David Pye]

Oh, sorry!

I was using 1.6mm grey-banded ones, 1mm SS filler rod and 5mm diameter SS rod.

Cheers,

David

 

[chunkolini]

Another query about welding small bars.
I made these out of 6mm stainless.

A bit more detail.


Mig welded them and it drove me mad. Distortion is The Enemy! I had to make I think it was four of them.
I also made a smaller one about 1m diameter out of 3mm rod. That was 'fun'.
Mig welded them all.

For the joints described by the OP I would clamp them up with a small gap, ideally onto a piece of copper then work along the join with a slight weave. the large fillets on my webs were because I like the look of them they are not needed. Also if you go with mig use antispatter.
Chunko'.

 

[langy]

Try 2% thoraited (red) you will find them better.

Oh, sorry!

I was using 1.6mm grey-banded ones, 1mm SS filler rod and 5mm diameter SS rod.

Cheers,

David