Advice

[Charred fingers]

Hi, I've been making small section steel supports for freestanding stained glass panels the better halfs business mainly from 10x10x10x1mm wall
channel and 5mm drawn round bar

I've been using a mig for this but find it difficult (small target), but the other
problem is a lot of the welds are visible and the mig welds are hard to tidy up
on such a small scale and was wondering if Tig would be a better option.
I can produce really neat welds with oxy/acet and as Tig is a similar
process (heat source , filler rod) I don't think I would have a problem picking it up.

 

[wobblemonster]

Why can't you Mig them from the back, then you won't see the weld, or if you have O/A why dont you braze them??

 

[backpurge]

Would have thought with a bit of practise you could make a really neat job of this with TIG.

I'm assuming it's mild steel, if so, remember to use TIG specific filler,not oxy/acet or MIG filler wire as you could get gas pores, keep the majority of your heat directed to the thicker bar and you should be fine

 

[Charred fingers]

Thanks for the comments, Wobblemonster the problem is some of her work is visible from all sides and she wouldn't be keen on the colour difference of brazing, besides the O/A is at work and I spend too much time there as it is.

Backpurge it is m/s though some may be done in s/s in the future for external pieces, I get the impression that with Tig that the process is slower which gives better control of the weldpool. Guess I'd better start looking for a Tig

 

[BillJ]

How is it being finished? If the colour of the joint is visible then I'm assuming clear lacquer? TIG does (in my limited experience) give better control of the weld-pool. I find the control quite a bit better on stainless than on mild.

 

[brightspark]

can u not drill the channel .slip the tubing in through the hole and weld from the back ??

 

[Charred fingers]

Hi Bill the whole thing is cleaned and finished with gun blue then waxed.

Brightspark the prob with that is the panel slides neatly into the channel and an internal weld would interfere with that

This pic will give an idea , the channel side supports and 5mm bar stffeners on the back aren't obvious, not supposed to be mind. Its 600 wide by 1800 high to give an idea of scale
Thanks again.

 

[Archie]

Have you tried just cutting a triangle out of the sides of the channel and bending it into shape? I know that doesn't solve you problem but it might make things easier. In answer to the original question, yes, I would think TIG would be a better option.

 

[Charred fingers]

Archie I get your drift with that, but with panels like the one above where we pushed the boundaries in terms of size on a single pane I wouldn't want to weaken the channel, not so much when its insitu but for handling purposes.
I think the general consensus is a Tig would be better so that the way I'll go

 

[Hitch]

I dont think Tig is a better option, i do agree with Brightspark.

Drill through the channel, and poke the bar through, 7/8mm weld underneath between the sides of the channel. Leaving the bar a couple of mm shy of the edges of the legs, will allow you to weld it and not have too clean it off, or if you day, a very small amount.

 

[Charred fingers]

Thanks Hitch, I think the first pic is misleading the bar is welded to one leg of the channel I just stacked those pieces to show what i was using.

As the Lead came pictured in the channel or the Zinc came to the left are a snug fit I cant afford anything to intrude, it would be ok it the bar was welded through the web as the first pic suggests a small ground down internal weld would only make the channel stand off a small amount.