HF Spot welder help

admin

I'd appreciate some input from any of you gentlemen that know your way around a Harbor Freight spot welder. The following pictures depict the unsatisfactory results of my first attempt at spot welding.*I know you get what you pay for in this world, but sometimes it is what it is. Any help would be appreciated.Welder is new*220V*HF getting lots of juice.Material is 1 mm hardened sheet metalHold time- a second and a half.Surface prep was just a dremil w/ sanding wheel.Thanks in advance..Tong mating ok?Please focus on the*two welds on the upper right.If it isn't obvious, this is a picture of the surface were the top tong did it's thing.Bottom tong weld surface.Picture doesn't show it well, but weld surface*pulls a fair amount of copper*off the bottom tong every time. Work has to be "pulled" free from the bottom tong.This is the*inside*of the weld after being pried apart.Doesn't take much force to break the weld. There is no "tear" so to speak.
Reply:hardened sheet metal ? if a high carbon steel alloy no matter what spot welder you use i would expect brittle welds from the sudden cooling of the weld metal. to be attempting the impossible rarely works. go spend $10,000 on a heavy duty spot welder and do not be surprised that you still cannot weld hardened steel without making brittle welds.i am not sure what power you need to weld usually i turn power up to max. sometimes you have to let go that is not spot weld too long but release it. that is usually you close tongs spark seen and open tongs normally fairly fast. as for HF spot welder i am not sure what power it puts out and its rated capacity. i would read instructions and not expect much when at max capacity. i believe HF spot welders are for car auto body metal of 24 ga which is fairly thin .024" ??
Reply:I have a Miller spot welder. The tong(s) contact is one tong directly in line with the other tong, not at an angle, as you show.You are getting just the little bit of electrical current with that slight surface contact. If the tips were directly one on top of the other, you would have about double the surface contact.That being said, I believe that what TomB says is true, in regard to the hardened steel that you're trying to weld. I have a more difficult time spot welding stainless steel than mild steel. Different metals react differently.Try spot welding some known softer sheet metal together, as a comparison.Rich
Reply:Originally Posted by WNY_TomBhardened sheet metal ? if a high carbon steel alloy no matter what spot welder you use i would expect brittle welds from the sudden cooling of the weld metal. to be attempting the impossible rarely works. go spend $10,000 on a heavy duty spot welder and do not be surprised that you still cannot weld hardened steel without making brittle welds.i am not sure what power you need to weld usually i turn power up to max. sometimes you have to let go that is not spot weld too long but release it. that is usually you close tongs spark seen and open tongs normally fairly fast. as for HF spot welder i am not sure what power it puts out and its rated capacity. i would read instructions and not expect much when at max capacity. i believe HF spot welders are for car auto body metal of 24 ga which is fairly thin .024" ??
Reply:yes i find the tongs need filing to make a smaller contact area after some time. .thats is after many welds they get too wide and heat spread out too much and they need to be made more pointed or smaller dia tip ends to concentrate heat. i have seen special files for spot welders but i just use a regular file
Reply:Originally Posted by steelsurgeonI have a Miller spot welder. The tong(s) contact is one tong directly in line with the other tong, not at an angle, as you show.You are getting just the little bit of electrical current with that slight surface contact. If the tips were directly one on top of the other, you would have about double the surface contact.That being said, I believe that what TomB says is true, in regard to the hardened steel that you're trying to weld. I have a more difficult time spot welding stainless steel than mild steel. Different metals react differently.Try spot welding some known softer sheet metal together, as a comparison.Rich
Reply:Usually in the ads they say "mild" steel, so bad type of sheet metal to weld and bad angles on the contact tips.
Reply:You get what you pay for... No way around it.