MOT Battery Tab Timed Welder - Weld Analysis' Please!!!!

[markz]

PCB Board, welding cable clamps, copper rods, Programmed ATMEGA328
http://www.avdweb.nl/arduino/hardware-interfacing/spot-welder-controller.html

I followed this, paying close attention to the warnings because its very very dangerous and deadly.
http://www.avdweb.nl/tech-tips/spot-welder.html

MOT was from the back of a Value Village in their "pile of crap they can't sell" bin. I believe it was a 1400W maybe a 1100W.
I cut the top off at the weld seam, then took out smaller wire winding, wound 2 wraps of 2AWG welding cable, then epoxied the top back on and clamped it overnight. BTW its a 3 prong cord, the ground prong was bolted to the transformer itself, I ground down the metal all around where it was going.

Parts from ca.mouser.com

120Vac Transformer from Farnell/Newark - Paid waaaaaaaaaay tooooo much on s/h!!!!!!!

Welding Cable from Princess Auto
http://www.princessauto.com/en/search?Nrpp=45&Ns=sku.price_listPrices|0&Ntt=welding%20cable

Copper Pipe from Home Depot

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[Gregory]

Glad it's working, and well done on finishing it.

Personally I wouldn't have cut and glued the transformer, I would think that would change the EM properties of it for the worse.

 

[markz]

Thanks

Like the Billy Joel song "You may be wrong for all I know, But you may be right"

So I am about to weld me up 2 packs of 4P8S of A123 M1A's and HOPEFULLY go riding today in this overcast light rainy day of +5oC. Be the first ride in a long long time.

So please feel free to comment on my welds. Previous to this post are some weak welds mixed in with some strong welds. But the thing I dont know is, are the strong welds suppose to have a bigger weld spot as seen in some of the pictures.

You know you need to take a break when the 2AWG welding wire gets hot.
Latest round, setting 8 for the positive and setting 9 for the negative. Needs to glow a bit.

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[markz]

Why?
Its only off by 0.5V when comparing during charging.




Now its 28.3V, probably 10-15minutes after iMax was done.
Now its at 28.1V, probably an hour now after iMax was done its charging.
27.9V after a couple of hours.

Is this normal?

 

[marty]

Batteries are like beer. After charging they foam a little then they settle down.