sharkytm

lkaliburn, how are you doing the scratch-starts? I'm still having a lot of trouble getting the arc established. I regind the tungsten, and make sure everything is clean, and all I seem to be able to get is the tungsten sticking or popping an arc, then dying.

Toysrme

More amps & be quicker & gentler negra

lkailburn

what thickness metal/what amp are you running at?

i find that when my tungsten is freshly ground, and my base metal is super clean, i almost don't even have to actually touch the metal. its almost like i can start it just by ALLLLLMOST touching.

but for actual motion, i rest the cup on the metal and rock the torch to contact the tungsten to base metal then rock back, then pull away


update* i found my local hardware store sells 3/32 36" mild welding rods for 50cents each so i picked up two to practice with . i'll post up pics tomorrow

-Luke

HiProfile

I got my HF 90amp welder going the other day, and I was having issues mainly due to tungsten & basemetal contaminants. I didn't have much for cleaning supplies at the time, and couldn't get scratch-start to work well - leading to ---- on my tungsten and ---- left on the metal.

I fixed the metal cleaning with the obvious ----, but for scratch-start, I do this: Lay the torch at an angle touching the cup on the metal, then tip it until the tungsten touches the metal. My HF has pre/post flow, so it senses the shorted connection, shoots gas, then applies the amps after a second. Goes like 'touch, pshhhh, lift, buzzzzz" With a little practice, I got it to start w/o actually touching the metal. Unfortunately I ran out of gas by the time I got to that point I only had a 20cf tank, as I didn't want to waste the 80cf of c25 I got for free. I'm going to buy a 120cf tank now, since I'll eventually be getting a synchrowave or something.

BTW I think I'm going to grab some 10k pots from radioshack and MIG up my own pedal. I can already see a $15 plastic pedal breaking in a week. BTW if you make yours, make sure its a linear tapered pot, not audio tapered. Audio is expotential, for reasons of sound filling a 3-d space, etc.

lkailburn

update 7

here's my first shots at 3/32 mild rod. it certainly adds a lot more filler at a time. these welds were just ontop of the metal except for the weld on the pipe running about perpendicular to the others. there was a cut in the scrap pipe that had a small gap so i did a pass over that. that was my very first shot with 3/32 and is terrible.




i really need to find some thinner scrap plate metal (thinner than 1/4" which is all i have now) and get better at torch and filler hand controls.

-Luke

SpankedYA!

I never found running straight beads on flat steel helpful. Weld flat stock together. Do lap welds and then do butt welds.

ColdShot

just a few obsevations

you don't need to back purge mild steel

the autgenous root pass and fill bead being any wider than the thickness of the parent metal is excessive, practice making very tight beads, use a smaller electrode, the smallest you can without it burning too fast, torch head looks light enough so perhaps you would think about cup sizes along with juggling electrode stick out so you can try "walking the cup" which may result in much finer work if that technique just happens to suit you

unless dealing with very exotic super duplex stainless steels which also are very unforgiving of interpass temps in excess of 300 degrees, you certainly should autogenous common stainless anytime you are able and being able to do so and completely, generally indicates excellent fit up like your mild steel pieces show

if you don't need 100% penetration for your part, your choice of metal thickness could likely be thinner and work just fine

for sure it could be half thickness if made of an exotic metal more tolerant to high heat

and you really need to be able to stitch some fine beads to do those and the results hold up

I have some 0.065" wall pipes on one of mine that have not one single fill pass anywhere, 316L stainless with micro welded seam

has held up perectly for 4 years now

looks like you have the knack for it

and for sure practice stitching some very fine beads on that flat stock after you nail pulling very fine puddles thru it

t_cel_t

hey some thinsk i have noticed when welding, you need to keep the tungston like 1mm above the pool, i know it sounds weird but it really helps on the penetration. also if you look at your pool close you will see a little white dot that is like spinning around all crazy, that means you are getting good penetration.

lkailburn

bringing this back from the dead :-)

I finally got around to getting my tank refilled, i ran outta gas after the last practice runs. next is to do some lap and butt welds

Damn masters is keepin me so busy.

-Luke

lkailburn

UPDATE 8 OMG gaslense ftl??


As you guys know i just picked up that gas lense kit from that seller on ebay. I've literally only used it for maybe 4 practice welds.

Well tonight, im going on like a 2" bead when bam i see something fall into my puddle so i stop the weld. The ceramic cup broke in half and just fell into the weld!!! ? WTF

idk what happened i just watched it fall off




Did the screen clog and over heat the cup or something? i don't understand

-Luke