Kemppi Welders

[kiwi]

I was on the Kemmpi website and saw a new technology (or new to me) called Micro Tack. The page contains a video of a welder using the Micro Tack feature on some sheet metal fabrication. Do any American made welders have this capability?
Thanks,
Nick

http://www.kemppi.com/inet/kemppi/en...2?OpenDocument

[Mr Bigs]

That's pretty interesting. That helmet looks cool also.

[Engloid]

All you have to do is set your output switch to "panel" and bump your pedal or fingertip control, and it will act like an off/on switch. From there, just set the panel amperage to where you need it to get a quick tack.

[kiwi]

All you have to do is set your output switch to "panel" and bump your pedal or fingertip control, and it will act like an off/on switch. From there, just set the panel amperage to where you need it to get a quick tack.

Engloid,
Thanks for the response. That video is really cool. The welder makes that sheet metal fabrication seem effortless.
Thanks again.
Nick

[kiwi]

That's pretty interesting. That helmet looks cool also.

I agree...that helmet looks awesome.
Nick

[ctrhenry]

never seen them in the states , but they use them at one of our fabricators in South Africa, they swear by them

[dseman]

Any of the maxstar/dynastys will have programmable spot functions which allow you to program the amperage and duration of the arc. The time duration is from 0.10->25sec. The Kemppi has both microtack and spot functions. Microtack is default setup with lift arc but can also be used with HF. Their spot function operates between 0 --> 10sec. But the microtack has a much finer control and is intended for very short pulse durations. The range is from 1-->200millisec. To put that in perspective, the maxstar/dynastys have a minimum setting starting at 100millisec. You can appreciate how small a pulse that is by watching the video shown in the link.

The net is that the Millers would work in that application as well, just set it to the minimum pulse width for the spot function.

Kemppis aren't yet available in the U.S., but I wouldn't mind taking one for a drive.

-dseman

[awill4x4]

I'll have to check and see if my Kemppi MLS 2300 has that feature, it was one of the earlier machines so I'm not sure if it has it or not.
Even it it hasn't got microtack it is a beautiful machine to use anyway.
Regards Andrew from Oz.

[2024T3]

Micro or Mini Tack

After seeing the Kemppi video, I had to try it, because the work he was demonstrating was very similiar to a lot of our welding.
We have a Dynasty 350, but I had never used the spot function, and very seldom use the lift arc, so it was a few hours of fiddling around, but I'll have to say I am pleased with the results.

I expected that 16 ga stainless (1.5 mm) wouldn't be too hard to get to work.
As I recall I used about 80 amps and .10 seconds ( the minimum ).
I used 1/16 ceriated because it supposedly has the best arc starts. It seemed to be necessary to put the post flow to 1 second, because otherwise the auto post flow would see the 80 amp spike, and lock you out from restarting for a few seconds. That wasn't completely consistent, and I'm not sure how I was interacting with the machine's timing, but post flow to 1 second for all spots seemed to cure the issue and I could mini tack as fast as I wanted. To get the most consistent fuse, I found that I would put the tip of the tungsten right down into the bottom of the groove and lift or rotate it out a bit. I couldn't do it as consistently with lift arc, and got better results with touching the bottom, backing off, and starting with the pedal with HF. Picture shows the results on 304 ss. Fused it no rod with no problems, and the tacks are not visible in the final fuse weld.

Of course, stainless is much easier to tack than aluminum, and I figured if I could get aluminum to tack, that would be a huge plus for our operation.
First up .090 (2.2mm) 5052 H32 open corner weld. For tacking used the 1/16
ceriated, 175 amps .2 seconds 400 hz 80% balance. ( I wanted as many polarity reversals as possible in my .2 seconds) Results in picture. It's necessary to stay in really close, and in fact I got the best tacks if the tungsten was so close that the puddle was just on the edge of touching as it fused. The really great thing about this tacking method is that the aluminum remains cold enough that you can really squeeze in the joint to touch and have your fingers right next to the weld. Unfortunately there is no magic, and for the aluminum to fuse, it does have to touch. The tacks were not visible in the final no rod fuse weld.(picture) None of the tacks broke while welding, but they are weak enough you can break the part by hand.

Next to try was .040 (1mm) 5052H32 aluminum. Tacking 110 amps, .10 seconds. Same frequency balance and tungsten. This is where I found lift
arc pretty much impossible to use. You really have to be in tight, and centered in the joint for it to melt in both sides. I didn't stay at it long enough to get 100 percent fusing on the tacks, but pictured is a 32 inch long curved section of scrap, tacked about every 3/4 inch. I was able to no rod fuse weld 20 inches before I got to a section which wasn't tacked well enough, and it opened up with the heat. This is probably 10 times further than I've fused such thin aluminum before. (used triangle waveform, 60% balance) Of course tacks with rod in thin aluminum have issues with melting in the lumps, so even if we need more strength than a no rod weld gives, I think that this may change the way we weld. The first thing may be to change programming to do 1/4 or 1/2 lap joints instead of full open tangent corners. This will make it a bit more difficult for the press brake operator, but easier for the welding. The other thing might be to make a special set of no slip padded jaw pliers that you could use to squeeze in corners while you tack them. It requires a lot of hand strength to bring together 14 or 16 ga stainless that is under bent a bit. This would still be way way faster than getting out the bar clamps though.

The one thing that I couldn't get to work well was my expensive auto darkening helmet. I needed a lot of light on the work to see the tiny tacks,
and eventually went to grind mode and blinked for each tack. The aluminum and stainless are just too reflective of the strong spot light. Maybe Miller can put bluetooth in their welders which will communicate with my helmet and tell it it's ok to be not dark. Or maybe not. One more thing to go wrong.

Look forward to getting more experience with this method.
Hopefully others will share their experience too.

[dseman]

Nice job! See it does pay to read the owner's manual and find out all the capabilities of your machine---whatever machine it may be.

You didn't mention which miller helmet you have, but did you try increasing the sensitivity? If you have the digital elite, did you try the X-mode which triggers based upon the electromagnetic waves generated by the arc rather than just the visible light?

-dseman

[fun4now]

looks great, thanks for the demmo.

just reminds me of all the functions i'm not using.
oh well maybe some day.

[kiwi]

looks great, thanks for the demmo.

just reminds me of all the functions i'm not using.
oh well maybe some day.

Hey Fun,
Can you do the same on your T/A 185?
Thanks,
Nick

[fun4now]

yep

yep, just has to be in HF TIG mode. then you just set the spot timer and the amps to be used. then trigger with an on off device. ie. push button or foot or finger control.

i didn't look up the hole process section, just the quick reference page that explains all the functions like slope, spot and so on.

the TA-185 really is an impressive little TIG unit. i have not used a 1/3 of its ability's and still managed to TIG steel, SS, and aluminum, all with great results. the only draw back is the amount of time i have used it. long enough to use up one 80 Qu. Ft. and thats about it in 2 years i think, i would have to check on that. oh ya i also burned about 3 Lbs of stick's threw it as well. enough to find out i really su ck at stick , again the welder is way past my skills. i love it for TIG and do a great job, just cant seem to get the hang of stick. had a fella come over to try to help me get the hang of it and got a little better, still no where near as nice as my teacher. so i cant blame it on the welder, he did great.

T.M.I. i suppose, but you asked.