another newbie first ish attempt

[general--lee]

hi welded some 2.5mm tube together didnt have a a veru good fishmouth but was close , some went very well and looks pretty good and some didnt have a look at pics sorry if they a bit blurry but hopefully your be able to see enough to take the mick or offer some advice??

thanks ken

 

[Wozzaaah]

Sorry Ken, we can't possibly offer advice when the pics are that blurry, you can't make out any detail whatsoever. Post some better ones please.
Oh and I think you may have got a bargain with that machine!!

 

[general--lee]

ok i did wonder they did look a bit better than that on my screen at work but now i at hoem on laptop there well blurry will take some more tomorrow

sorry ppl

 

[weldingscotty803]

what tig is it?

scott

 

[general--lee]

3 phase 250 amp SAF nertinox ?
(now for sale for £250 ish)

 

[general--lee]

better pics

thanks ken

 

[Wozzaaah]

Hmmm, what gas and rods are you using there Ken?
I'm no tig expert but you've got lots of craters/blow holes and oxidisation that shouldn't be there. Are you certain they're proper tig rods and not just gas rods? Pure argon, not argon/co2 mix?
What flow rate is your regulator set to and are you welding indoors our outdoors?

 

[general--lee]

indoors pure argon and pretty sure there tig rods i have gas ones as well, flowrate i think was 10lpm ? im not 100% sure that the gas works everytime you hit the button

 

[Wozzaaah]

Hmmm. that's the type of weld you get when you use gas rods, not tig ones.
10 l/min is good, do you have a flow meter or are you just going by what the regulator says? Are you checking the flow while actually welding and not just pre-setting the reg at 10 l/min as that will drop as soon as you start welding.
If you're unsure of the gas working every time then you need to sort that out before you go any further, get yourself a 'peashooter' from weldequip or diywelding, it fits over the ceramic and measures gas flow at the exit point so is far more accurate.

 

[Wozzaaah]

One other thing that I hadn't even thought of, what is that tubing? Is it plain mild steel or something more exotic?

 

[general--lee]

sorry i have just turned on gas and checked flow rate it was on 2lpm i usually have it set to 10 lpm (reckon someone here fiddle with knob)
tubing is cfs tubing off ebay (brought to set up my tube bender like sams )
so thought would cut that up and use that ,

as for gas working it seems to be everytime just now i tried it loads and worked everytime might of been cos i didnt relaise i was on 2lpm ( dam dam dam )

 

[Wozzaaah]

That'll be why then!
Whack it up to 10 l/min, have another go and show us the results.

 

[general--lee]

i will do .... i must admit i dont check the gauges everytime as its only me who use them as its only me in my unit but guy over road has used them in the past perhaps he changed them ,anyway will have a go asap
thansk for replies so far

 

[general--lee]

just did a quick weld with gas up (instead of putting a cyl head back on )

im quite pleased ......

 

[Wozzaaah]

There's a definite improvement over the first set of pics, by no means perfect but you're heading in the right direction.
You're a bit hit and miss with your aiming, the weld bead favours one tube then the other but other than that, not too bad for a learner. You look like you've mostly got decent fusion there, one or two spots maybe a little 'cold'.
I'm going to hand you over to the tig experts now and get ready for work, nice 12 hour night shift .

 

[runnach]

Runs look a tad on the big side, probably due to experience, more importantly, and as you have mentioned previous, your fit up is poor, the better the fit up, the better the weld, all in all tho not too bad now you have flow rates sorted.

Use this if struggling with calcs for scalloping tube.

http://metalgeek.com/static/cope.pcgi

 

[snowcat]

fit up is key, as said your never get an even weld if you don't spend the time on the prep first. heres a pic of a very similar joint and the fit up before weld, it would also have been welded as a root and cap, get the root even and the cap will flow easily over the top, tubes harder to muster than flat work as your pulling the torch and the filler around the tube, thus changing the position, try and move forward slightly slower, also....

 

[madkayaker]

do you drill that out first or after the weld?

 

[snowcat]

drilled first, pipes easy decent holesaw makes short work, that was a vent tee, which was why I made the fitting up......

 

[madkayaker]

i see thanks Snowey