Ground Clamps..

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OK..There is this discussion about ground clamps contributing to "Arc Blow" "Arc Wander" whatever you wish to call it..I do not experience any of that at any time..At least not that I know of..But however..Here is what I have experienced..I am using one of these 500 amp models..Should not be a problem right?If I do not clamp it to the piece with a small C-Clamp it will get so hot sometimes that I have to use a glove to get it off the piece..And sometimes the clamp is over 100 inches away from the weld zone..If I do clamp it then it stays at room temp..The clamps that pinjas has put a link to look like I will be getting one of those also..Anyone else get the "Hot Clamp Syndrome"??...zap!Last edited by zapster; 08-21-2010 at 04:15 PM.I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:Yeah, I use one of the bigger c-clamp style grounds , but mostly I seem to melt tweco quick connects.  Most of the time it is just a bad connection that may be arcing inside or when I air- arc at around 600. Arc blow I have only noticed with SMAW. Sometimes it can be hard to troubleshoot as we may have multple (5 +) welder's working on the same structure or pipe. Anyone ever had to weld on a structure that had been magnatized?? ( bad arc blow)2011 Dodge 3500 diesel duallyLincoln SA-200Lincoln SAE-300LN-25'sLincoln Idealarc R3RMiller Trailblazer 302
Reply:Food for thought, whatever we are generally clamping to is a hard surface for the most part. Most clamps, regardless of amp rating, come provisioned with a few sharp points or a series of points. Sure those sharp points are good for penetrating paint, rust and the like but even when clamping to clean flat surfaces you total contact area cannot be anymore than the points.  For flat surfaces I wonder how much contact area that clamp Zap posted actually makes if you could get under there with a microscope and calipers or many others for matter? I can see where a guy might want to get clamps tailored to suite if you work on primarily one surface configuration. GP clamps for general purposes, flat bladed clamps for flat surfaces, round clamps for round surfaces and so-on. I think having both jaws bonded by something other than a hinge pin helps too."The things that will destroy America are prosperity at any price, peace at any price, safety first instead of duty first, the love of soft living and the get rich quick theory of life." -Theodore Roosevelt
Reply:i have had hot ground syndrome with heavy FCAW or Spray mig but never tig welding.   You might be better off just switching to a C-clamp style groundVantage 500's LN-25's, VI-400's, cobramatics, Miller migs, synch 350 LX, Powcon inverters, XMT's, 250 Ton Acurrpress 12' brake, 1/4" 10' Atlantic shear,Koikie plasma table W/ esab plasmas. marvel & hyd-mech saws, pirrana & metal muncher punches.
Reply:The small points of contact, especially if already somewhat burnt, are often the problem.  From the web site, WeldingTipsand Tricks.com, the author talks about the problem and offers a possible solution.This contact/heating problem is 10 - 100 times larger in maginitude with Magnetic Particle Inspection (MT) where stationary magnetizing units routinely use 1,000 to 6,000 amps to magnetize parts.  Some way of assuring the part ends are fully in contact is essential else the heavy current will melt/arc/burn the ends of the part.  The method normally used in MT is braided copper pads with a neoprene backing that will conform to the surface of the part and assure good electrical contact.  However, lead plates and braided leaded/copper is also used.MT typically used braided copper backed by neoprene and the pad size is typically 8 inches x 5 inches or so.My thinking is that if you could slip a thick braided copper 'sock' over each end of welding the ground clamp, the problem of poor grounds would likely end.But where can you buy braided copper?While not big enough in diameter, the tinned-clad copper braiding in typical coaxial cable looks good.  Just need a much bigger diameter cable.My $0.02Rick V 1 Airco Heliwelder 3A/DDR3 CTC 70/90 amp Stick/Tig Inverters in Parallel1 Lincoln MIG PAK 151 Oxy-Acet
Reply:Good post Rick V.....zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a  dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:I don't think that I saw anybody mention the idea of taking some sandpaper or emery cloth to shine up the metal where you are going to clamp it.   If that does not solve the hot clamp problem you might want to check how good the connection is between the cable and the clamp.  In this context, heat = resistance.   Bad connections get hot.However, if you can solve the problem with a c-clamp, that argues for a bad connection between the ground clamp and the work.RichardSculptures in copper and other metalshttp://www.fergusonsculpture.comSyncrowave 200 Millermatic 211Readywelder spoolgunHypertherm 600 plasma cutterThermal Arc GMS300 Victor OA torchHomemade Blacksmith propane forge
Reply:You can use a Vise Grip C clamp for a ground clamp and not worry about it again.
Reply:I have been thinking about replacing my ground clamp so I will be following this thread.
Reply:As long as the cable is attached tightly in the clamp and the surface is clean and shiny, you should not have any trouble. But, that kind of clamp has never given me much confidence. (I have one also.) The spring pressure is just lame. The large aligator-clip-looking clamps always seem to stay cool though. Or try the vise grip or C clamp sort. Attached ImagesCity of L.A. Structural; Manual & Semi-Automatic;"Surely there is a mine for silver, and a place where gold is refined. Iron is taken from the earth, and copper is smelted from ore."Job 28:1,2Lincoln, Miller, Victor & ISV BibleDanny
Reply:i like the clamps from home depot. copper contact surfaces, and copper braided strap from one side to the other; and only $15 or so as i recall.Dynasty 200DXPassport plus w/ spoolmate 100victor 315c oxy/(act and prop)Miller digital elitemilwaukee power tools
Reply:Hi, There was a thread started about at the beginning of this year which also was on ground clamps. I put in a post on the one I made out of a G Clamp which I still use and it doesn't heat up or leave any marks on what ever I clamp to, it has about 3 square inches of copper plate making contact. However the longest I have welded on it at on high amperage at any one time was for about 1 hour running about 350-400amps but it didn't get hot at all. Cost about $7 and about 20 minutes to make. My post was #9. it's cheap and effective. http://weldingweb.com/vbb/showthread.php?t=37915Miller Auto Invision 456 + S-62 wire feederC6240B1 Gap bed lathe16 ft3 air compressor16 speed pedestal drillHafco BS-912 Bandsaw
Reply:I use the same ground clamp as in Zap's op and I have never noticed the ground clamp heating up. I have been looking to buy another because I was also thinking that there is not much contact because of the shape and also the flat ones might hold better. I found some pics of different clamps.This looks like it would work good.I want one of these for when a clamp style wont hold because of cable weight or something.This is (I think) a chinese clamp cheap on ebay.I was thinking of switching to one of these because my iron worker buddy said that is all they use on the big jobs. Also Red-D-Arc usually uses these for their rental. And they happen to be the cheapest.This is a Lenco flat that looks like it would be nice."Where's Stick man????????" - 7A749"SHHHHHH!! I sent him over to snag that MIC-4 while tbone wasn't looking!" - duaneb55"I have bought a few of Tbone's things unlike Stick-Man who helps himself" - TozziWelding"Stick-man"
Reply:I got this one for the truck and it has been working good.http://www.stronghandtools.com/products/groundhog.htmlThey also make v-block that screws onto it for clamping onto pipe.MM350P/Python/Q300MM175/Q300DialarcHFHTP MIG200PowCon300SMHypertherm380ThermalArc185Purox oaF350CrewCab4x4LoadNGo utilitybedBobcat250XMT304/Optima/SpoolmaticSuitcase12RC/Q300Suitcase8RC/Q400Passport/Q300Smith op
Reply:I always make a quick tack of the clamp to the table or the workpiece (if it doesn't matter).  A quick weld will make a sure path without much doubt.  Yeah the clamp gets messy after while, but they will last a long time if done properly.Esab Migmaster 250Lincoln SA 200Lincoln Ranger 8Smith Oxy Fuel setupEverlast PowerPlasma 80Everlast Power iMIG 160Everlast Power iMIG 205 Everlast Power iMIG 140EEverlast PowerARC 300Everlast PowerARC 140STEverlast PowerTIG 255EXT
Reply:Originally Posted by lugweldI always make a quick tack of the clamp to the table or the workpiece (if it doesn't matter).  A quick weld will make a sure path without much doubt.  Yeah the clamp gets messy after while, but they will last a long time if done properly.
Reply:i use a magnetic clamp for all my pressure work, zero issues.
Reply:I'm with pressure welder here, I've had multiple problems with ground clamps and surfaces over the years. Try putting a ground clamp on a pipe (line, fence, etc.) halfway down the line. Problem solved: http://www.thermadyne.com/tweco/news...d-clamps-.htmlOnly when the last tree has died and the last river has been poisoned and the last fish has been caught will we realize we cannot eat money.                                         -Cree Indian ProverbSA 200 LincolnVictor Torches
Reply:The new miller clamps work very well.Have we all gone mad?
Reply:Originally Posted by sn0border88The new miller clamps work very well.
Reply:I have the stock small Lincoln ground clamps.They have a thin steel body, but that is not what is mostly handling the current.  Because the ground lead goes to a lug/stud that connects to a braided copper strap that goes to the two brass(?) clamping jaws.  So copper and brass are where the current goes through and the steel body just holds it all together.  It works OK, within the limits of the machines.I haven't noticed the clamps getting any hotter than the leads really, so to me that indicates that the 'system' (lead wire and clamp) is working OK.I also did pick up one of those Stonghand GroundHog clamps just like DesertRider33 posted.  It was marked waaay down, so I got one (the last one in the store?).    I would have had to think pretty hard about whether the item was needed at the original price, but marked down it seemed worth it.I put a short (1-2 ft?) whip of about the thickest cable that fit into the ferrule on the StrongHand clamp.  Assembled it and I think I put some sort of lug ring on the other end and then I can just put the OEM steel spring clamp onto that lug ring and then the GroundHog clamp can attach to the workpiece.  Works like a champ.The OEM spring clamp sometimes wiggles and twists and such, because it is just held onto the workpiece by the spring tension.  Which really isn't all that much force.The GroundHog clamp isn't quite as fast or as easy to use as the spring clamp, because like a pair of ViseGrips you have to adjust the jaw gap to the correct setting.  Not tough to do or all that difficult or time consuming, but not quite as quick as just popping the spring clamp on.  The GroundHog clamp is waaay more secure once you clamp it on though.  I give it a +1.  I like it.  Only really works on flat workpieces within the grip range of the jaws.What I haven't like about the magnetic ground clamps that I've seen has been the generally kind of weak magnets they seem to have.  If they put some strong rare-earth neo magnets in them, they would seem better to me but they all seem to have some kind of wimpy ceramic 'pot' magnets.  Like a refrigerator magnet.  Bleh.  Especially on a round workpiece (pipe/tube/round bar) they wiggle and twist all over the place.  The best laid schemes ... Gang oft agley ...
Reply:Zapster - I bet you've got some corrosion on the surface of your clamp if you haven't cleaned it lately.Sure, buying a brand new clamp will give you fresh copper surfaces which should work well.  But I'll bet you can easily "restore" your old clamp to also work fine if you just clean the contact surfaces.  I would use a hand scratch brush, just like as if it were aluminum and you were removing oxides for weld preparation.I have a new harbor freight version of that clamp, and find it has generally worked very well for my up to 200 amp welding.  As long as I remember to actually clamp it to something. Surface area of the clamp to work contact will generally be proportional to the pressure applied, if you were to look on a very small / microscopic level.  Having a clamp with a different, shape, or "teeth" may help it to not slip off the part, but I don't think it will conduct better unless the clamp pressure is higher.I do like the idea of having a screw to tighten the clamp rather than a fixed pressure spring.  You could adjust the pressure of the screw depending on if you want to clamp to something fragile without bending it (light pressure), or to something thick with heavier clamp pressure, for a lower resistance connection.Aside from that, having a wide range of clamping thickness seems like it would be useful feature in a clamp.  I've had occasions where I wish my spring loaded clamp would open up just a bit more...  Just some food for thought.Thanks for the helpful fabrication project threads, by the way; I always enjoy reading them.
Reply:Jakeru-  if you look at the clamp I pictured, and the one in the first post you can see there is a huge difference in contact area if placed on a flat plate, simply due to the design and not proportional to the force applied.Have we all gone mad?
Reply:No hot clamp here.This is the one that came with my Kemppi welder. Attached Images
Reply:I had the same problem with my Miller 210.  I got to watching it one day when a buddy was using it and I noticed a small arc at the bolt where the cable attaches.  I took it apart and the clamp had corroded where the lug contacted it.  I cleaned the area up and put a washer under it and on top of it and tightened it down.  No more heat issues.  I think the two different kinds of metals had worked together to cause the corrosion.Please dont mistake my enthusiasm for talent!Originally Posted by zapsterOK..There is this discussion about ground clamps contributing to "Arc Blow" "Arc Wander" whatever you wish to call it..I do not experience any of that at any time..At least not that I know of..Anyone else get the "Hot Clamp Syndrome"??...zap!
Reply:I think if you look carefully at the China one, its actually made in Australia.