I have seen these on TV and around on the internet... has anyone used them? Are they worth the money? I know there are different ratings, but looks like it would come in handy... Was just thinking of grabbing one but wanted to see what your opinions were on them. Spaz
for welding its nice when you dont have anywhere to clamp to. Been in a few spots like that. If thats the case, i just tack weld a piece of scrap to where im welding for the clamp to hold, and grind it off later.
Spaz, What is your application? I think they would work ok for a temporary ground but is that what you want? Walt
Well I am constantly making quick repairs to farm equipment and building small things like battery trays for different people. I am fixing to start working on the frame of my 54- but I think getting a good ground on the frame itself would be better for that situation.
I use a 220 mig gun and also have a lincoln stick machine... would these be good for both or just the mig?
They suck. When I worked at John Deere while I was laid off from Case, the one guy on days was too lazy to use a threaded clamp to hook on the frame once we put it on the floor to weld, so they stuck one of those magnetic grounds on. It sucks. By the time I got done welding it was very hot to the touch. They went through 2 of them (for 2 week time in between getting the new one we used the regular c-clamp style one) during the 3 months I was there. For the small stuff like battery boxes, you'd be better off with a welding table, farm work, or frame, I'd never use one of these. @bigdog928, a plasma cutter uses less amps than a welder does, also depending on what model plasma cutter you're using, my thermal dynamics doesn't even need a ground to cut, it just cuts better with the ground.
We use it and it works fine for light duty (body n exhaust), heavier stuff i'm not to sure, they come in different Amp ratings. right now using the 300 amp. http://magswitch.com.au/general/industrial-welding.html
Where they set has to be clean, clean ,clean as does the surface of the magnet. Any slag, spatter, grinding dust, mill scale or just plain ol dirt will make them get hot. The hotter they get, the less they clamp to the work making them even hotter. Had one on a pinch welder that lasted for years. The heavier the welded material, the tighter they hold. Any type of ground clamp will get hot if it does not have good contact with the material. Grind a spot on the material and put your clamp of whatever type on the clean spot with the cable side of the clamp on the cleaned side. Even if the clamp has the copper connecting strap, use the cable side. Clean the brass contacts in the clamp on a regular basis, like every time it is removed and reattached. A couple rubs with fine emery cloth will do the trick.. Coarser cloths will leave some abrasive in the soft brass which affects the contact. A clean contact will make a noticable difference in the performance of your welder.
They sell them at the local ag supply store that handles Hobart stuff but I'd have to agree that clean bare metal to make contact or the resistance will be high enough to cause problems.
I made a few out of the big magnets they sell at swap meets with a bolt through the middle so you can clamp your ground clamp on there. They work good I wouldn't use them in place of just clamping onto the ground given the option though.
anti bling I thought you HAD to use a ground when plasma cutting? We have burning tables and hand plasmas and none of them will work without a ground. (sometimes not directly to the part but at least ground the table you are working on) also we use magnets like that frequently just make sure the size is appropriate for what you are using. spray arc welding is a lot different than 12v car systems.
Not on all machines, my Thermal Dynamics Cutmaster 51 I don't have to have a ground for it to arc. I could cut plastic with it if I wanted to. And it will cut metal without a ground, it just does it very poorly.
Same here. we have an 8x20 bed on ours, it will not work without a ground, and works poorly if the ground isn't right.
CUT PLASTIC?!?!? With A Plasma Cutter? My world has now been turned upside down. The only way i could imagine cutting plastic is if you had a thin piece of metal on top for it to arc to. But you have to have an arc to cut.
I've used one for my arc welding more than ten years. I love it. One precaution as the magnet tends to pick up steel garbage It does not grab well when dirty. The center contact must be adjusted for good firm contact. Formerly I used vice grip pliers with a stud welded on but they got hot at higher currents. Even battery clamps work but they tend not to last very long.
AntiBling is referring to the pilot arc. It will start without a ground, and it will cut very thin material. It will also burn out the circuit board in short order if you keep doing it. No substitute for knowledge...
I havent used a plasma cutter in atleast 7 years I guess. Someone gave me one that was poorly taken care of off the back of his work truck when he upgraded and I used it a couple of times but never worked right... so traded it off for some hand tools I needed. I just havent been able to bring myself to buy a new one.
well that makes a little bit of sense i guess. we really don't cut anything under 1/8'' or maybe 14 ga. at our shop on the hand plasma, so the pilot arc won't even warm some of the steel we cut without a ground. i guess you can cut steel with a mig welder too but you don't see me doing that either. I'm now done being way off from the original thread topic. Sorry everyone
I bought one of those magnetic clamps once. Big pita, kept collecting grit making poor contact. Now I grind a place to hook the ground to, or a place to vice grip to and clamp the ground on the vice grips. Think I finally threw the worthless magnetic clamp away a few years ago. I also ground my plasma cutter. Works much better and is easier on the tips. Gene
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