First attempt scratch tig

[wallopadonkey]

OK here we go again,
got a scratch tig set from weldequipe (thanks again steve) to go onto my oerlikon inverter.
wp17 torch, no 7 ceramic, grey ended ?? tungsten made it into a point with grinder, i only have argoshield light gas so it will have to do for now!
oh and the rods are oxy acetylene filler rods as it was what i had.

ok took a few minutes to get the scratching bit right just did a few sort of spot welds lol (stuck rod to metal)
then a little run with no filler at 60 amps probably a bit high but had to start somewhere.

next 2 runs front

this is the back of the metal to show what little penetration there was lol

then tried to spot 2 pieces to set up a fillet join

then other end

got it a bit hot i think !

litttle bit more to make sure it stuck

tried to do a little fillet lol
OK THEN!
crap so far, here is an overview of the warzone in the first 10 minutes

outside edge joint

inside view

second side of the joint (polished)

inside of the joint

constructive criticism please i now have the right filler rods and a tungsten that looks like a witches nose lol
covered in filler.

cheers for looking

 

[matt1978]

Hi Mate,

I can't stress enough that you need to get Argon, not Argoshiled light or simerla.

Thats why your Tungsten will get eroded dead quickly and also why your welds are very black and with porosity.

You will notice a unbelivable improvement when you get the right gas.

Keep up with the practise, your doing good.

Cheers,

Matt

 

[vtec_lude]

Also clean the metal that you are welding on. Bet it pops and bangs all over the place?

 

[rodofgod]

Hi All!

The MAJOR problem you're having wallopadonkey is using oxy-acetylene filler rods!

Regardless of the fact that you are using a totally inappropriate gas for TIG welding, the fact that you are using oxy-acetylene filler rods is a complete NO-NO when TIG welding!!

Get some pure argon gas and some filler wire made for TIG welding (ask for PZ6500 or something beginning with ER70 or A15/A18)!

http://www.welding-supplies-online.co.uk/merchant-2-24.ihtml

oxy-acetylene filler rods are totally not suitable for TIG welding for various chemical reasons, hence all the porocity and other defects! And get some pure argon gas!!!!!

Regards

 

[chunkolini]

YUP!!
I can remember the same process. 2 years struggling with the wrong gas, and the wrong rods. Get the right gas and suddenly it becomes merely difficult rather than bloody impossible. However getting this far with wrong bits and bobs does help when you get the right bits and bobs.
Chunko'.

 

[wallopadonkey]

ok got a 3ft bottle of argon (pure) on the way £33 with £2per month rental
key gas wrexham
also got stainless and mild tig double de-oxidised rods from steve weldequipe
so after this weekend is over 2 x kids birthdays, party and mothers day wil have a go using the proper stuff.
you all know how it is got the gear gotta have a go for filler we were going to use the bits of steel that the air shears left us lol so oxy rods much better than that lol

cheers for the input prolly be a full report on wed/thursday
cheers dave

 

[pastiche]

wrong rods??

i am confused i have been welding nearly 20 years the last 10 mostly tig work(stainless mostly ) and as far as i am aware a filler rod is suitable as long as the make of alloy is as close to the parent metals as poss i must admit i have no experience of gas welding but i always understood that as long as there was no flux involved then a 316 or mild steel rod is exactly what is says on the tin ie the same as the parent metal regardless of weld process used, if fact that is the beauty of tig or gas if you can cut a strip of paret metal off this can be used for welding(have done so many times with stainless, bronze and other metals, awlays a good method if unsure exactly what materials you have been given to weld!) as for the gas yes pure argon is the most useful alround gas for tig work however better results can be acheived in stainless with a argon helium mix(can't remember % although 5% helieum rings a bell) and on mild steel acceptable result(altough not the best) can be acheived with argosheild gas mixes.
your biggest problem appears to be dirty metal + overheating so even with proper rods.... and pure argon you will need to play with either moving faster adding more wire or turning power down. also ensure that tungsten is nice and close to weld pool angles stay constant and wire remains within gas sheild whilst hot keep practising and i find nice clean material.
also watch gas flow far more important than beginners realise too much is def as bad as too liitle

 

[dannyweld]

you should be spending more time preping that steel with a grinder than it takes to tig it, bit like painting.

 

[rodofgod]

Hi All!

pastiche, first of all, it is better to try and TIG weld using parent metal strips as filler wire than using oxy-fuel filler wire. That is not a major problem, It's not ideal but it's better! The trouble with oxy-fuel filler wires is in the make up chemistry of the filler wire. It is not designed for use as a filler for TIG. I could mention double de-oxidised and treble-de-oxidised wires but it all gets very complectated! Try welding some 'rimming' steel or what is known as a 'unkilled' steel with A15 grade TIG filler wire using TIG and your will soon see the problems wallopadonkey is having!

As far as shielding gases, pure argon gas, is in the main, 99.9% of the time. Additions of Hydrogen or Helium (up to 5%) can increase arc temp and therefore weld speed/heat input in stainless and aluminium applications. The use of Ar/Co2 gases i.e.argosheild gas mixes are really a no-no with TIG! It can be done but the weld chemistry is completely shot! Tungsten wear is dramiticaly increased as well!

Regards

 

[pastiche]

sorry rodofgod i think i was unclear about the argosheild thing i would never recomend its use in tig process and it would def not make it any easier for a beginner but the piont i was trying to make was that with correct method a acceptable weld(or at least aweld that visualy looks ok) is relativly easy to acheive and that the problems wallop was having could not be solely blamed on the gas although he may well find it much easier with the argon.
as for the rods there is no fundemental diff between oxy rod and tig rods . 316 stainles rod is made 316 stainless steel regardless of what heat source you are using to melt the metals. and regardless of which process you are using the important thing is to match the rod to the parent metal (diff alloys are used for jioning disimilar metals).
just to sum up when buying rods you ask for a rod to match the material not for the process.
as a afterthoufht i have when nothing is available even stripped the flux coating from stainless mma rods(never tried mild but would presumably work if you had to) and successfully used these for tig

 

[matt1978]

Mild steel tig filler wire is triple dioxidised, Oxy Acet Brazing wire is not Pastiche, so there is a major difference, you will get poristity if tig welding and using Brazing wire.

 

[pastiche]

welding and brazing not the same thing at all can not weld with brazing rod at all brazing rods have lower melting piont???

 

[shenion]

TIG brazing is different type of rod. Regular brazing has zinc that will flare up due to the high arc temp. I tried TIG brazing with some unknown uncoated rods, was a real mess.

As long as the rod is the exact same spec it will work. ER70S-6 MIG and TIG wires are the same.

An ER70xx arc rod or a scraped similar gas rod will be different as it does not have the -6 option (or -2, -3) to specify deoxidized and silicon content.

 

[rodofgod]

Hi All!

pastiche, there seems that some confusion has crept in here! wallopadonkey is trying to TIG carbon steel, not stainless. That's a big difference. Like you correctly stated, 316 is 316 to a point.

With carbon steel, it's slightly different. For a start, whilst not impossible, it is very,very hard to cut or weld stainless steel with oxy-fuel equipment unless you have very specialised gear. It is impossible to do without this gear! If you don't believe me, then try it yourself.

You will not find oxy-aceytelene stainless welding rods in your local welding stockist because it's not used.

TIG wires and oxy-aceytelene wires for carbon steel are totally different chemically and you will never successfully weld using TIG process and an oxy-aceytelene filler wire.It will always be full of porosity.

Regards

 

[wallopadonkey]

my mistake here i feel i have caused some of the confusion the mild steels rods are tig wire double de-oxidised and the stainless rods are 316 hope this helps

dave

 

[hotrodder]

FWIW/for anyone that's interested chemical compositions for various different steel filler alloys. Starts with a15, a18 (er70 type) fillers, A1(RG45) and A2(RG60) oxyfuel fillers are on pg 8. Stainless and aluminium... filler alloys are the same for both TIG and oxyfuel, oxyfuel requiring flux too

Wallopadonkey, bet you saw a BIG improvement with the right filler and shielding gas!

 

[dannyweld]

you can use 316 wire to tig mild steel, i use it myself if i,m stuck, have tried oxy wire, it just does'nt work.

 

[hotrodder]

You can end up with a brittle weld (formation of martensite?) welding carbon with stainless so not a good idea for anything likely to see much stress.

 

[wallopadonkey]

hi there i still havn't had the chance to play with gas and wire lol did the patch on the van instead on my day off.
just got a little stainless job for my boss which i'll try to do this weekend
give it all a whirl