TIG welder advice

[Kev888]

Congratulations on the purchase kev, if you ever get suck just give me a shout on here
Forgot to mention you'll need a bench grinder with a fine stone wheel for sharpening electrodes (if you dont allready have one).

Thanks thats very kind!

I'll have a go and see what happens; hopefully this weekend or maybe one evening if work permits. I don't yet know if it'll be a case of needing relatively minor improvements or else a complete failure to weld anything.

Ah yes, I do have a bench grinder, but it needs a new wheel - if indeed it still works. Thanks for the reminder; I'd overlooked that.

Cheers
Kev

[Kev888]

I need some advice.
What's the best way to explain to my lovely other half, my best friend, my soul mate, that I am going to leave her and move in with Kev?
It's just such a difficult subject to broach. Does "Tara, then" work?

Heh heh! I suspect you'd regret it - your other half sounds like a much better bet to me. Maybe you could buy her a welding course for her birthay or something; if she was still with you afterwards, you'd have the best of both worlds?

Cheers
Kev

[barneey]

Dont forget Kev = Mandy at the weekends

[froggi]

Kev.... If you need a brief tutorial, I'd be willing to help out mate.....Could maybe pop down and show you what's what (obviously depending on distance, lol).......

Also you might be well advised to get some copper tubing/sheeting to make some back purge bars as there's bound to be some "coking" going on when/if you're welding any stainless.

The use of the purging minimises this "coking" effect that's created by the back of the weld being exposed to the atmosphere (air) while you're making a nice and neat shiny weld on the exposed face.

[Kev888]

Thanks very much for that!!

Thanks also for the heads-up on back purging - think I'll practice on some cheap mild steel to begin with, hopefully that'll give me time to sort something out; theres a decent metal stockist not too far away so they could have some copper offcuts, and I'll definately have some old bits of pipe about. So much to fiddle with - great stuff!

Cheers
Kev

[Kev888]

Well its here! There was a moment of doubt when there was no gas cylinder with the UPS delivery, but it came minutes later on a TNT van. The name on the cylinder is freshford of manchester and as r-tech offer a swap service I'm quite surprised to see its all new and clean looking. So all present and correct - great service, most impressed.

The only oddity so far is that the website says the supply needed is 22Amp/5.3KVA - so this is what I was expecting and indeed the welder seems to have 22-24A marked on it depending on voltage (220-240vac). However, the manual 'only' talks about needing a 240VAC 13Amp fused (slow blow) supply... I can't see it mentioning 'just for low powers' or anything..

I suppose I'll try it on 13amp and see what happens, but I can't see any way in which I could run it without an industrial socket for higher powers - a 32A commando presumably. Anyway I've dropped them an email to check; the generator power needed is different in the manual too.

But not tonight, have got work to do sadly

Cheers
Kev

EDIT: just noticed that the off/on switch at the back is a 32A circuit breaker like you'd see in a consumer unit - think that pretty much answers the power supply question then! I can feel a dual-use welding/boiler socket coming on...

EDIT2: R-tech got back to me with an updated manual, saying the printers had made an error with the paper copy (caabooom!...oopsey!). Its now 22Amps so it looks like I'm going commando

[Kev888]

First attempts today - only on 3mm steel so far. Initial doddering steps with beads and a butt weld (of sorts), graduating to a fillet weld:


So as you can see, far from perfect but there's a definate improvement and metal has been joined

I seem to have spent most of the afternoon grinding steel off the tungsten, but its improving. More worringly, my 137bar 9L argon cylinder is down to about 70bar already, and thats without any back purging... Think I'll have to find a local/cheaper supplier.

Cheers
Kev

[Eric]

That's good progress, definitely getting there.
Can't tell by the photos, but it looks like you might be welding carbon steel. If so, be extremly careful when you go onto stainless to avoid any possible contamination.
Well done
Eric.

[Kev888]

Thanks Eric - thats most kind!

Yes, I thought it best to try mild/carbon steel first, tomorrow I'm going to try some very thin stuff and later stainless (If I've got any argon left by then). I'll definately follow your advice about contamination, and I'll need to rethink the back-purging; I was going to make a spray arm, a bit like a mini-sparge arm, but flooding both sides with argon is going to be even more costly. Unless I can find a cheaper supplier, anyway.

Hmm, i wonder if I could use CO2 for the back; I know its no good as a shield for the tungsten, not sure about the back of the stainless though.

Cheers
Kev

[barneey]

Kev, I`m going to stop reading your posts about welding.. it might give me some very expensive ideas I know nothing aboout welding but the second one looks good to me, cant wait to see the pot results.

[Kev888]

hehheh, well at least its not a shiny welder

The pot results - yes, you and me both! I suspect even if I improve the technique, its going to be challenging to avoid everything twisting in the heat.

Cheers
Kev

[Eric]

Thanks Eric - thats most kind!

Yes, I thought it best to try mild/carbon steel first, tomorrow I'm going to try some very thin stuff and later stainless (If I've got any argon left by then). I'll definately follow your advice about contamination, and I'll need to rethink the back-purging; I was going to make a spray arm, a bit like a mini-sparge arm, but flooding both sides with argon is going to be even more costly. Unless I can find a cheaper supplier, anyway.

Hmm, i wonder if I could use CO2 for the back; I know its no good as a shield for the tungsten, not sure about the back of the stainless though.

Cheers
Kev

I'd be just a little worried if you are contaminating the tungsten electode after contact with the parent metal or filler, such that you could get some carbon into your stainless workpiece. You need to avoid any contact with the tungsten. Not so sure you need worry about gas at the back of the joint, but make sure you shield the workpiece from any drafts.
That's bloody good welding you've done.

[Kev888]

Thanks Eric, most encouraging! Yes, most of my learning curve has been with maintaining the electrode distance - getting used to keeping it at the right hight and not accidentally touching it down. I also need to work on more regularly/smoothly feeding the filler rod - thats usually just an aesthetic thing but I did manage to overshoot and contaminate the tungsten a couple of times; much re-grinding of the tungsten to begin with! Things are getting better all the time though, so hopefully I'll get there eventually.

I had a go running beads on a thin stainless caddy-type thing this am. It went surprisingly well - no holes blown, although the beads sagged a bit so they were as pronounced underneath as they were on top. So that was a promising start to the thin stuff, although I was surprised by how much distortion the heat caused; definately going to be challenging when it comes to welding the real pots. With no purging, the back of the welds seemed quite blackened, but in practice I'd have to grind them smooth and flush so maybe that doesn't matter?

I also realised this am that I've managed to give myself sunburnt arms, for a small distance between my gauntlet and sleeve; looks most odd - clearly more care needed on PPE

Cheers
Kev

[Eric]

You've obviously cracked the process Kev, but as you say, distortion is going to be a big problem.
I would have thought you'd get enough gas to the back through any gaps in joints and worry if you got porosity, heat alone could blue or blacken thin stainless.
OK on the uV, nasty.
Good luck,
Eric.

[Kev888]

Unfortunately things are suddenly on hold; just switched on my shiny new tig welder to have another practice, but got no arc and instead very smelly smoke billowing out of the machine

Nothing has changed since the last practice so I don't know whats going on, but its not looking good. Not sure if I should try to exchange it or get my cash back and try another make <sigh - or some JB-weld..> Hopefully R-tech will respond positively..

EDIT: yes they did I only emailed last night and i've got an email and voice message this morning already. They say its very unusual and are sending a new machine out and collecting the old one tomorrow.
I'm really impressed with their customer support; I guess no-one can avoid the odd failure but its how they deal with them that makes the difference.

Cheers
Kev