[Louie1961]

I am practicing laps on 1/8 inch CRS coupons, using a 3/32 tungsten ground to a sharp point. The steel is sanded to bright shiny metal and thoroughly scrubbed in acetone (even though it is CRS it has a slight amount of rust on it). I have my amps set to a max of 125 and using the foot pedal to control actual amps. #7 cup, 15CFH of argon.

my problem is that I am having trouble getting the heat right...either I have not enough heat, and I get a puddle on the top plate and puddle on the bottom plate, but they never really come together, or if they do, it is seriously boomerang shaped. OR I hit the other extreme and I am eating too far into the top place. I am holding an approximately 70 degree angle to the plate, mostly pointed to the bottom plate, and a 20 degree travel angle. My arc length is very tight, as tight as I can get it without dipping. probably no more than a 16th of an inch. I have the same problem with the syncrowave and the AHP.

What's the secret sauce that I am missing? is it the torch angle?

[Otto Nobedder]

I suspect (though I'd have to watch you weld to know) that you are not tight enough... too much space between the tungsten and the puddle.

I'll be interested to see other opinions on this.

Steve S

[Louie1961]

I know that arc length is crucial, and I have 8-10 hours of running beads on plate. So I am pretty confident that I am not long arcing it. I could be wrong of course, but I have been giving this a lot of attention. But please don't take this to mean I don't appreciate the input.

[Otto Nobedder]

In a thin lap joint like that, the goal is to establish the puddle on the lower plate, and push it to the upper plate to tie in, and back away. Rinse and repeat. This can be one smooth motion, with practice, but it takes patience at first to not burn back the upper material.

This gave me fits for a while, lap-welding 16 ga. stainless hinges to 16 ga. stainless door panels.

Steve S

[Louie1961]

I had noticed that I could finesse the puddle around but wasn't sure if that was correct or not, as I really never noticed Jody doing it in his videos. Then again, there is about a million miles of difference between his skills and my lack thereof. I will have to try that later. I also noticed the laywire technique helped me a bit as well. I suspect i just need more practice, but without someone looking over my shoulder, its a bit harder to advance.

[Louie1961]

today's practice. I was trying what you suggested with the puddle on the lower plate. It really helped, thanks. Welded @125 amps, with the foot control, 1/16th ER 70-6 filler, 3/32 2% lanth tungsten ground to a sharp point, 15cfh of argon. The plate is 1/8 inch CRS, sanded to bright shiny metal (had some rust) and cleaned in acetone. The pad of beads is 1/4 inc CRS. I used two different machines. Mostly done with my new syncrowave 250 and a 17 torch, but when that got too hot to comfortably handle I switched to my AHP with a 20 torch. middle joint on each set of plates was with the AHP. I find the foot pedal on that machine just doesn't give me the same level of control as the sync 250 with an SSC pedal. Such is to be expected.

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[jwright650]

You're getting it....something else that helps is to keep a tight fit between the plates, clamp them down tight, if need be.

[Braehill]

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[Braehill]

Here is one done with the pieces clamped down and tacked so they don't separate during welding.

Sorry didn't mean to send that in two posts.

Len


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[Otto Nobedder]

[quote="Louie1961"]today's practice...
quote]

Looking good! You seem to have found the "feel", and it's just practice from here to make it look how you want it to look.

I'd suggest practicing adding more filler, so you lose the sharp edge at the top (this requires focus on that edge in particular), but take your time. It's difficult to completely eliminate that edge, and I often sand it lightly for paint on a lap weld. (Paint doesn't like to cover a sharp edge.)

Steve S

[jwright650]

today's practice...
quote]

Looking good! You seem to have found the "feel", and it's just practice from here to make it look how you want it to look.

I'd suggest practicing adding more filler, so you lose the sharp edge at the top

I agree, it looks like it is slightly under filled, adding more filler should fill in that slight undercut along the top edge. Good job

[Louie1961]

Thanks for the feedback, I appreciate it.