hi all,
anybody have good or really bad experiences with the cheap spot welders, ie NOT Miller, Hobart, or Lincoln?
i've got a wire feed 220v, but i think that i would rather use a spot welder for the bed repairs i'm doing. i know to buy the best tool you can afford, etc.
there is no rental near me available.
i don't mind if it only lasts a couple of projects then craps the bed, but i would like the welds to last.
thoughts? thanks

 

I'd just plug weld using your mig, be cheaper in the long run.

 

I have a 120v wire feed I do all my body work with, I welded the caps on the bed to fill in the stake holes, I even welded sides for a toneau cover on onather bed with no problems. it was less than $200 six years ago. Its a german name I thin Hauss...something like that.

 

I elected to buy a used Miller after looking at the feedback on Harbor Freight spot welders (both good and bad). The deciding factor was the tongs are available several places, and of course you can always sell a Miller when you're done with it.

The bad things I heard about no-name units was the clamping mechanism; some broke quickly, no repair possible.

I have MIG and gas welders but if I can use the spot welder I will! Fast super clean, and very strong. I used it to replace the rotten flanges on the bottoms of my bed front. Two 14 gauge pieces, solid as a rock. You really have to try to burn thru, too!

 

Are you talking the spot welder like Ross has, the old "one in each hand pokers", or the modern stud gun for pulling dents? MIG works fine, just requires more finish grinding.

 

good information, thanks for sharing the knowledge. But now I am a little lost. I thought that the MIG welder was for spot welding and most body work. What is the difference for a spot welder. In all the youtube videos I watched I was under the impression that the welding machines are mig wleders.

 

Spot welders are typically two electrodes made in a giant clamp like arrangement. You grasp the two pieces of sheet metal to be joined at the point where the spot weld is to be made and squeeze them together. A trigger switch send a short (literally!) burst of electrical current thru the electrodes from one side to the other. The instantanious heat produced melt the two pieces together. This method was the major method to attach sheet metal components on the manufacturers assembly line. The resulting "dimple" can be found all over our trucks. The pros are it's fast and produces minimal distortion. The cons are that the surfaces must be overlapping, the weld need to be in a place the spotwelding clamp can reach, the attachment is only a small point, it's difficult to determine the quality of the weld without tearing it apart, and it cannot be used to weld any other type seam. A replacement for the spot weld called a plug weld can be done with a wire feed welder by drilling a 1/4-5/16" hole thru one of the sheets where you wish to join them,clamp them together and fill the hole with weld. You can get spotwelding electrodes for a MIG machine but you can also buy inexpensive spot welding setup that plugs directly into the wall.

 

The other "pro" to using a spot welder over plug welding with a MIG is it produces a correct-looking bond, which is important if one is doing a proper restoration. It's tough and time consuming (if you can do it) to finish a plug weld to resemble a spot weld, if that's the look you're after.

 

correct terminology is resistance welder. lots of people think a mig is a spot welder. biggest thing on one in my opinion, is that the cheaper ones have crappy duty cycles. you do a couple of welds ant wait till it cools off and some and let it cool, etc.... if you are doing major amounts of it, you wont like the cheapies. they get hot quick and lose penetration i.e. weak welds. if you have the time to kill and don't mind the wait, they'll do the job. they have come so far with resistance welders in the last few years. last time i checked on the one i want for my shop it was 10 grand. OUCH!!!! but they are liquid cooled contiuous duty..

 

and the cheaper ones all surfaces must match up and be perfectly clean. the high $ ones will zap thru e-coat and panel bond.

 

Yep, this is the kind I have: Miller - Spot Welders - MSW & LMSW

The winding ratio (like a transformer) is something like 1:10,000, the current at the tips is ~4,500 amps, very low voltage. Concentrated on an area about 1/8"-diameter, it gets things hot right quick!

Here's what I did on the front panel of my bed, which was totally rotten off on the lower 2 - 3". I had a shop bend me up an "L"-shaped section 6 ft long with an offset to allow a flat joint on the inside.

 

I bought 2 over the years, both at swap meets. One is a 220v with a set of jaws, a short set of beefy leads and a separate transformer. The second is a panel spot welder with two separate hand held leads. It worked well when I repaced the original metal bed floor in my 49 F-1. I was able to hold one inside the bed side to bed floor flange and the other outside the bed side. It is also 220 V. I paid less than $100 for each one. They are older and USA made.

 

Bill, that second one you mention is the "poker hand" one I was talking about. I'd love to find one. Guy I know has one, and he put whole new CJ7 body sides on in a relatively short time. Worked great. Plus side of it is being able to weld on just one side.

 

I don't see how the "poker hand" type would work?? How can you align the two electrodes? How canyou apply any pressure? And how do you trip the switch if you have an electrode in each hand, a foot switch?

 

Here's a link: Lenco Correct term is "panel-spotter"

EDIT: better link... http://lencoautomotive.com/index.php?q=product&p=l-4000 They also sell tips for rivet-mold and dent puller pins.