Page 1 of 2
Tired of getting zapped!
Posted: Wed Nov 18, 2015 8:37 pm
by dunkster
Can anyone out there please explain to me why I get continually get eff'n zapped while AC'ing aluminum?
It happens sporadically for no rhyme or reason...sweaty hands, dry hands, high humidity, low humidity, doesn't matter. Gloves I'm using are Tillman tig, both goat and deer skin. It usually happens as filler nears the puddle w/o contact of any kind, which leads me to believe it's the hi freq. I'm just stumped as to why some days can go without incident and others I need a stack of old welding gloves under both hands for insulation...can be a real PITA at times, and last night was well beyond that. I'll just say clamps can actually fly,
As for the machine, it's a big blue synchro 350. Hi freq setting is between 30 and 35 and it is not grounded directly to a ground rod. It was grounded at it's first home years ago, but I had the same problem then so don't think that would be a remedy.
Appreciate any suggestions.
Rusty
Re: Tired of getting zapped!
Posted: Wed Nov 18, 2015 10:07 pm
by Poland308
Check for loose connections on the ground cable. You may want to take them apart and clean the connections. Also is the cabinent of the welder in contact with the bench? Is the bench grounded? I once had a bad ground cable connection and when I finished running a long weld I looked up to see my corded grinder smoking and partially melted. The ground path was easier through the grinder laying there than it was through the clamp. If your getting shocked it's because your the easier path. I try real hard not to do this intentionally but if someone is helping you fit pipe and you start your arc on the side of the pipe or fitting your partner is holding really steady for you then they usually get bit.
then again there was that one guy!
Re: Tired of getting zapped!
Posted: Wed Nov 18, 2015 11:04 pm
by Bill Beauregard
dunkster wrote:Can anyone out there please explain to me why I get continually get eff'n zapped while AC'ing aluminum?
It happens sporadically for no rhyme or reason...sweaty hands, dry hands, high humidity, low humidity, doesn't matter. Gloves I'm using are Tillman tig, both goat and deer skin. It usually happens as filler nears the puddle w/o contact of any kind, which leads me to believe it's the hi freq. I'm just stumped as to why some days can go without incident and others I need a stack of old welding gloves under both hands for insulation...can be a real PITA at times, and last night was well beyond that. I'll just say clamps can actually fly,
As for the machine, it's a big blue synchro 350. Hi freq setting is between 30 and 35 and it is not grounded directly to a ground rod. It was grounded at it's first home years ago, but I had the same problem then so don't think that would be a remedy.
Appreciate any suggestions.
Rusty
I'd guess it's the hi freq overrunning source zapping you. It can jump a long way. I get it when my ground pops off, the continuity between work and table is poor, a hose/ wire is in bad condition, I forget who said it is around 1200 volts. Try inspection, and switch to deionized water, or low conductivity coolant.
Re: Tired of getting zapped!
Posted: Wed Nov 18, 2015 11:29 pm
by xryan
HF can go a LONG way to finding an easier path to ground.
I've more than once had the HF arc but no welding power when the ground has been knocked off laying on the dirt, gravel, ashpalt, concrete, etc.
#1 check ALL the ground connections. Bare metal for the clamp to grip on, clean clamp, tight connections.
#2 zip tie the first foot or two of the ground and electrode wires together where they come out of the machine.
Sent from my SCH-I605 using Tapatalk
Re: Tired of getting zapped!
Posted: Thu Nov 19, 2015 5:11 pm
by exnailpounder
Are you grounded when you weld? By that I mean, are you touching something that is grounded like your table? I used to get zapped until I put my table on phenolic wheels and stood on a rubber mat and it all went away. Now I only get zapped when I forget to hook up the ground clamp. HF can do things that don't seem possible.
Re: Tired of getting zapped!
Posted: Thu Nov 19, 2015 5:48 pm
by rahtreelimbs
Same thing happened to me when I first started tig welding part of it was from sweaty arms. Second was an ungrounded welding table. A call to Miller tech confirmed that an 8 ft. grounding rod be put in the ground and a #12 awg wire attached to the rod and table. All this is separate from the normal electrical ground.
Re: Tired of getting zapped!
Posted: Thu Nov 19, 2015 7:39 pm
by dunkster
Thanks everybody...a lot of interesting ideas put forward. Before today, ground clamp was just thrown over a 3/4" round handled lock lever for adjusting table height, which was probably just a few scant points of contact. Just did a couple 1" joints today and made sure that ground was good and secure to the table this time. Work was clamped in a small D/P vise with a good footprint on the table. Thought I had it licked until that familiar sting got me again. So, it was old gloves, wood blocks, and tig fingers to the rescue. Todays zap, from my best judgement, came in thru filler hand glove and exited thru torch hand glove which was resting on the table. It always seems to get thru the glove at the point of most pressure from my hand.
@Poland: no, welder cabinet is not in contact with the table and table is grounded thru ground cable off welder, not to a dedicated sunken ground rod.
@Bill: coolant is straight distilled water.
@xryan: currently leads are not zip tied like you mentioned...what exactly would this do? will have to try this.
@exnail: only contact I make with the table is thru gloves I'm wearing at the time...no bare skin contact of any kind. learned long ago not to let this happen.
Guess my next test will be to put some nylon blocks under the table legs and see if that helps. From there will try dialing down the HF and then sinking a ground rod. Really appreciate all the help guys.
Re: Tired of getting zapped!
Posted: Thu Nov 19, 2015 9:54 pm
by Bill Beauregard
High Voltage is lazy, it wants to complete the circuit, but is willing to work only if it has to. With equipment in good condition this is easiest from the tip of the tungsten. A tungsten close to a grounded object can't be bothered with you. For some reason you are more attractive than your work. Is some part of you closer to the tungsten than the work is?
Re: Tired of getting zapped!
Posted: Thu Nov 19, 2015 11:41 pm
by dunkster
Bill Beauregard wrote: For some reason you are more attractive than your work.
Time to hang it up if this is the case......
.
No but seriously, all body parts are well away from the tungsten. As mentioned, it's tungsten to filler rod, rod thru glove and then thru me.
Re: Tired of getting zapped!
Posted: Fri Nov 20, 2015 1:14 am
by Poland308
Is it only on start up or in the middle of a weld.
Re: Tired of getting zapped!
Posted: Fri Nov 20, 2015 1:53 am
by dunkster
Can't say it's never happened in the middle of a weld, but can say for fact that it usually happens while filler rod is on approach for it's 1st dab, and that's literally in the approach, contact not yet made with puddle/work. This is why I suspect it's the HF, but why it's jumping to the filler where it then has to go thru leather is beyond me. Just knocked the HF intensity down from 33 to 25, but it still got me...just once though. So it may have helped, IDK.
Re: Tired of getting zapped!
Posted: Fri Nov 20, 2015 2:08 am
by Kevin_Holbrook
are you melting the filler rod in the arc or in the puddle ?
Re: Tired of getting zapped!
Posted: Fri Nov 20, 2015 2:17 am
by dunkster
Puddle.
Granted, I have melted rod before it's reached puddle before due to bad positioning or whatever, but haven't been zapped from it.
Re: Tired of getting zapped!
Posted: Fri Nov 20, 2015 2:29 am
by Kevin_Holbrook
just a shock in the dark , do the points need cleaning and adjustment ?
Re: Tired of getting zapped!
Posted: Fri Nov 20, 2015 2:44 am
by dunkster
Haven't done a visual insp of them yet, but I have owned this machine since brand new and it's done far more sitting over the past 14 years than been used. My best liberal guess is 200 hours max on the clock. And nothing over 200 amps...yes, I over bought. :banghead:
Re: Tired of getting zapped!
Posted: Fri Nov 20, 2015 3:08 am
by dunkster
dunkster wrote:Can't say it's never happened in the middle of a weld....
ok, scratch that one. just got nailed 3/4 of the way thru a bead.
Re: Tired of getting zapped!
Posted: Fri Nov 20, 2015 8:08 am
by Bill Beauregard
dunkster wrote:Bill Beauregard wrote: For some reason you are more attractive than your work.
Time to hang it up if this is the case......
.
No but seriously, all body parts are well away from the tungsten. As mentioned, it's tungsten to filler rod, rod thru glove and then thru me.
Now I get it! I'm surprised you are having success with welds. The arc must be short, 1to1-1/2 times tungsten diameter. Angle; I strive for 80 degrees from the weld bead, not square, but close. Form the puddle in the work piece, then dip. The arc must not directly heat the filler. Filler gets conducted heat from the puddle, which sucks heat from puddle to more quickly freeze it. The series of "dimes" which you may not see often in currency comes from this freezing action after each dip. The established arc before filler is added, sufficiently close, and at favorable angle should discourage arcing to filler. The high freq. high voltage isn't usually harmful. Current is low. basic insulation such as leather gloves wet with sweat in anticipation of shock make good conductors for this sort of power source. I'd bet you are making secondary contact with either table, or work. I might try one of those silicone hot mats they sell in kitchen stores to rest your filler elbow and torch hand on. Or, figure out some other contact point your body has with conductive grounded objects. Maybe a metal stool? HF isn't hampered much by weak insulators.
Re: Tired of getting zapped!
Posted: Sat Nov 21, 2015 12:49 am
by xryan
Regardless of how, where, when you are adding filler you should not get bit by the HF ever, with or without gloves, AS LONG AS YOU HAVE GOOD GROUND. I'd bet you still have poor grounding issues. As far as the zip ties, I can't remember how to explain it but it works to help HF leakage from your torch which may be the other side of your issue with poor insulation, cracks, etc. I'd bet a $20 you have poor ground terminals, damaged wire, corrosion, rust on table, isolated part, etc.
Sent from my SCH-I605 using Tapatalk
Re: Tired of getting zapped!
Posted: Sat Nov 21, 2015 9:31 am
by Bill Beauregard
xryan wrote:Regardless of how, where, when you are adding filler you should not get bit by the HF ever, with or without gloves, AS LONG AS YOU HAVE GOOD GROUND. I'd bet you still have poor grounding issues. As far as the zip ties, I can't remember how to explain it but it works to help HF leakage from your torch which may be the other side of your issue with poor insulation, cracks, etc. I'd bet a $20 you have poor ground terminals, damaged wire, corrosion, rust on table, isolated part, etc.
Sent from my SCH-I605 using Tapatalk
In the case of the electrical world we are almost always required to have all conductors; supply, and return in the same raceway, cable, or conduit. A magnetic field that expands, and contracts, and reverses will induce voltage in conductors. Bundling places equivalent, but opposing magnetic fields together. In large part, they cancel each other. This is the reason many higher power, high voltage cables are made like a coaxial cable. The grounded conductor surrounds the ungrounded one to carry any induced voltage to earth.
I'm not there, but I would look for insulation issues in your torch including your water if what I suggested before hasn't helped. My equipment was new, I have experienced it with three different welders when I inadvertently arc to the filler instead of the work.
Re: Tired of getting zapped!
Posted: Sat Nov 21, 2015 1:19 pm
by Gavin Melville
Perhaps my having only used two machines will show my ignorance, but on both of those machines (T&R, Kemppi) the HF stops as soon as the arc strikes.
Regardless I agree with the others - it's an earthing problem.
One more thing to try though - is the machine itself earthed on the power cord ?
Re: Tired of getting zapped!
Posted: Sat Nov 21, 2015 4:37 pm
by Bill Beauregard
On many machines it's continuous when you weld ac.
Re: Tired of getting zapped!
Posted: Sat Nov 21, 2015 10:18 pm
by dunkster
Bill, think I mislead you there. Arc length is always kept short and never directed at filler...well aware that the puddle melts the filler, not the arc. My point was that the filler can be 3/4 to 1 inch away while on approach to the puddle for the 1st dab and wham, I get tagged. No visible arc of any sort to it is seen. And it's always felt thru a gloved hand resting on a fixture or grounded table, never thru an elbow or bare arm so no, no contact with the table is being made by me other than maybe 2 gloved hands. Just stumped why it finds leather gloved hands an easier path than to the work/table.
And no, no metal stool.
And Gavin, yes, the machine is grounded thru the power cord but not thru a dedicated earth rod ground....which will be next.
Re: Tired of getting zapped!
Posted: Sat Nov 21, 2015 11:38 pm
by VincenzioVonHook
maybe you are just one conductive bastard. The techs come out on site all the time and check our resistance when they are bored. Its amazing how much it differs person to person and hour by hour!!!! I have never been bitten by my tig, but my mate will most times he uses it.
Its strange because he wears a lot more gear than me, and sweats a hell of a lot less. I was tigging in a singlet, boardshorts and thongs the other day (i know,........stupid as f) and had no probs. He jumps on in full blues and leathers and throws the fller across the room in 2 seconds flat.
Like you are stating, most times he is getting booted its approaching the first dab.
Re: Tired of getting zapped!
Posted: Sun Nov 22, 2015 4:19 am
by Hollywood1
This is ironic you brought this topic up because 3 days ago I got shocked twice while welding aluminum and stainless. I was told to put a grounding rod etc. As well. Never did, but I started wearing my welding jacket again and no more problems. If your bare skin touches the work table that's grounded you can get shocked sometimes. Hope this helps you out. I don't know why I quit wearing my coat for a while but now I do again and no problems. Oh, by the way, do not rap cord around your bare skinned arm and rest arm on the table while welding either. Thanks for all the good tips and, opinions u give to the forum. See ya, John.
Re: Tired of getting zapped!
Posted: Sun Nov 22, 2015 4:21 am
by Hollywood1
Also, I changed to a new pair of gloves. Originally I was grinding, sanding, and I even picked up some oily car parts with gloves. That may have been problem as well for me.