Well I finally got around to testing my Miller LMSW-52 230 Volt spot welder that I found on a shelf at work. I first had to make up an extension cord to run from my Dryer connection to the plug on the spot welder. After many attempts, I thought the thing wasn't any good and was ready to start punching holes for plug welds. I read one more article on resistance welders and discovered that the test pieces I was using were not clean enough, must be bare metal for the tips to contact and the tips had not been cleaned. After all was done I tried again and this time it worked. Thank goodness I don't have to punch all those holes in the roof and rear quarters.
Here's my question, is anyone out there familiar with this type welder? There are no settings for it, all you have is an adjustment for the pressure applied on the metal. The trigger just goes left or right, one pop and the sparks fly. I tried holding the trigger for just a second longer the second time but that just stuck the metal to the tips. I guess its just pull the trigger and let go. I'll know more tomorrow after I take the sample pieces to work to rip them apart.
I sprayed between the pieces with spray 3M Weld-Thru II Weldable, Corrosion Resistant Coating Part #-05917. This is what I plan on spraying where I plan on welding. If ya'll have a better choice for this tell me what ya'll use.
I'll post pics tomorrow of the pieces.

Make sure the electrodes are clean at the point ware they are clamped at the base of each electrode. Remove the tips from the electrodes clean the threads and make sure they are tight. Adjust the clamp pressure so you are just bending the electrodes when you close the clamp lever, with nothing in between them. Clean your tip faces at times between welds. The time you apply the weld trigger will depend on the material thickness. You just have to try and see what works. I have not had good luck with weld thru primers. I have found that they act as an insulator and I don't get good weld contact. When you have squeezed the lever and pushed the switch and nothing happens, it's because of bad electrical contact of the items your trying to weld together. I have the same welder and have done hundreds of welds. Your going to find it gets heavy to hold and wear some gloves as it will get hot.

Thanks for the reply Walt, and I got your E-mail with the manual, good info. Your right about it being heavy, got to be 50lbs. I'm sure it will be closer to 100lbs after 50 or so welds.
The strips I used were from the old quarters that came off the car. These welds were from holding the trigger just a split second. It REALLY took a lot of pressure and twisting to get it to break, I'm happy with it, but I will definitely do many more test before trying it on the car. Looks like the weld thru primer had no effect on the welds. You put a ton of these over to quarters and a roof and its not going anywhere.
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