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anyone got any scratch start tricks?

vanguard machine

Stainless
Joined
Dec 20, 2011
Location
Charleston and NYC
doing a metric ton of scratch start this and next week, hundreds and hundreds of but and fillet welds .75" x 16 gauge HRS.
doing the strike a match routine seems to work best for me, anything else and i get stuck to the work piece and fowl the tungsten way way too fast. but even with this technique i'm getting maybe 16 joints before re-dress.

it's working fine, all things considered, but wondering if anyone has any tips on getting better arc start without fouling or getting stuck. i've heard about guys striking off of the rod itself but i can't wrap my brain around that one.
I've only ever dabbled in scratch start as my old back up tig, may she rest in piece, had 4t controls for the thumb torch... which i got spoiled by.
on this job i'm running my later model sync 250, 1/16" tungsten (red), standard cup/collet body, running around 75 amps, HF off, gas flow at around 20 or so.
 
because i have no other way to arc start not having anything other than a foot pedal. i probably should have mentioned that this job has me doing repeated circles around the entire table so foot pedal would have been a major pita.
i messed around with lift start but it's too time consuming and just not as fast as scratch, at least for me. not to mention that it just doesn't seem reliable, again, at least for me.
(i did check the points gap recently and all is well)
open to any suggestions please and thank you!
 
Hold the filler rod against the part and use the filler rod to scratch start the tungsten. The copper coating seems to help it not stick. Takes a minute to get used to it but it works well for me. In high pressure pipe stuff this is mandatory sometimes to avoid any anomolies in the pipe for xray.
 
I've used a small piece of copper to scratch on
Worked better than the inside of the ss pipe I was welding in...yuck good luck
 
My circa 2001 Syncrowave250DX Lift Arc doesn't seem to take any time at all, but stop by the welding supply shop and pick up a finger tip control. Or if you are really too cheap for $100-$200 spend. Piggy back off your pedal's connector with a cheap hardware store momentary switch/button and length of light gauge SO cable zip tied to your torch leads. That way you can trigger the high freq. start and let the panel control the amps. Should be switch between pins A and B.
 
Torch switches are like £3 or so of ebay, you then need only a few meters of light 2 core cable a few cable ties and you have a torch mounted switch. Couple more quid gets you the connector to plug into said tig and about 20 minutes to put it all together. Depending on the plant you may have to also have a jumper in the plug to replicate the pedal being fully down to then get it to work at full pannel display amerage.

Personaly the only thing i ever plan to scratch start ever again is arc electrodes, and to be honest, even then if i could fit a switch and have HF for that i would!
 
well fwiw i have burned through a 160 bottle of argon and 10lbs of er70 and i gotta say, my scratch start technique has vastly improved, those inside t joints are a bitch but otherwise i feel good about improving my tig skills a little more with something like this, especially considering it's pretty much all been way way out of position work, IE, crawling around on top of the table or contorting myself into one of these 16" x 16" x 12' long frames. got quite a bit to go but for now i'm ok with no hf scratch start, other than the constant trips back to the tungsten grinder that is.
i will definitely be buying, or maybe building myself, a proper thumb torch but in the meantime you gotta use what you got to get the thing done.
 
^ To be fair i always find out of position awkward stuff shortens tungsten life a fair bit any how but then im not the steadiest of welders ever.

As to trips to the grinder, grind both ends of the tungsten’s (no fix for big blobs, but typical scratch start contamination it works well on) and also leave a few pre sharpened ones laying around the table can really speed things along.
 
^ To be fair i always find out of position awkward stuff shortens tungsten life a fair bit any how but then im not the steadiest of welders ever.

As to trips to the grinder, grind both ends of the tungsten’s (no fix for big blobs, but typical scratch start contamination it works well on) and also leave a few pre sharpened ones laying around the table can really speed things along.

i'll go one better..
i filled up a little endmill tube with all the little nubby tungstens in the box, ground on both ends, and have been carrying it around in my shirt pocket. ;)
 
I stopped carry a scriber in my shirt pocket after a near nipple piercing incident! Sure as hell are not carrying tungsten there!
 
haha! well, I would think he is putting them in something before slipping them in his pocket, I find an RX bottle to work if they are short enough, or a milling cutter telescoping tube.

as to the injury potential, well.. I herd a story of a jeweler "liberating" some saw blades from work, he slipped them in the front pocket of his jeans, and went to play softball after work.

yup, they pierced some of what would you LEAST want those jewelers saw blades to.. being they have a directional tooth, they had to be pulled ALL the way through.... :eek:

(never seen a more appropriate usage of THAT emoto!!!)

I hear tell that he NEVER took anything from work again...
 
oh and as to the OP, Vanguard, why was the lift arc "too time consuming? I hold in contact for one second, then lift. I would think if you had spent 1/4 of the time to refine your lift arc skills that you spent on the scratch start, you would have it down pat, no? if it doesn't start, try again, takes two seconds.

just no good reason to scratch start that I can see if your machine has a better way, but hey, knock yer self out!

I know a guy who started out learning on his grandfathers ancient gear, and he is most comfortable doing it that way, but if you have an alternate, you are going to get less contamination 99 percent of the time,and it will be faster, especially until you get better at it.
 
oh and as to the OP, Vanguard, why was the lift arc "too time consuming? I hold in contact for one second, then lift. I would think if you had spent 1/4 of the time to refine your lift arc skills that you spent on the scratch start, you would have it down pat, no? if it doesn't start, try again, takes two seconds.

i'm all about 'refining my skills', do it on a daily basis, hence the reason for this thread.
but..
there is no way in hell lift starting crazy out of position, upside down super contorted could possibly be even remotely as fast as scratch start. this wasn't bench work.
 
Scratch start can be a bitch, especially on a multiple-weld project. I welded two complete tube chassied drag cars together with my old Tig setup before I finally got my new welder with hi freq. Personally, I dislike thumb switches and the like for most work, because the torch moves around a lot while operating them, (maybe I'm just clumsy)but on a job like you have, there is no doubt that having a HF start button, at least, would be way more fun than multiple trips to the grinder and a collection of pre sharpened electrodes. Using the copper coated filler sounds like a really good idea if you are using that kind of filler, or maybe zip-tie a piece of copper to your filler wire hand so you don't have to search for it, since you are in a contorted position.
 
Dr hook, don't use them as thumb switches, rotate the handle around and use your first finger holding torch bettwen thumb and secound - third finger. Depending on what your doing you then end holding the torch more like a pencil or more a handle bar type grip.

As to out of position stuff, i love my flex lock torch, a std torch is just so damn clumsy in comparison.
 








 
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