MOT Spot Welder

Well, I am going to attempt to make a spot welder that can join two 1.2mm bits of stainless sheet together. Lets get started.

First things first, the tools! My awesome makita 18v battery drill and it's rather odd brother, and some hand tools, very handy yup.

Step 1 Prep your tranny

There are a slew of microwave oven transformer instructables out now, so really I shouldn't bother with this eh? Nahh, I did it this way ...

Notes on the pics.

Comments

[throbscottle]

Nice work - I watched the testing videos. Wish I had a clamp meter...

[Gaark]

I must admit, mine is a fairly cheap one. But seeing as I usually only work on residential up to medium machinery the 400Amp range is quite ample for my needs.

For some really nice meters check out Fluke ones. Or for a big selection try http://www.multimeterwarehouse.com/clampmeter.htm

[throbscottle]

Hmm, a lot cheaper than I thought they were, but in entirely the wrong country! I've actually started wondering how easy it would be to make a clamp meter probe for my standard multimeter. *Thinks* surely I can just put a winding on a ferrite core for this....

[Gaark]

Dude, don't worry about which country anything is in now! The interweb has freed us of all those restrictions *dance*

To make your own clamp meter you'd need to be pretty good with transformer calculations, or at least have some steady current drains you can calibrate your measurements with.

If you used a ferrite core there may be the problem that once installed as a current transformer you'd have to leave it in place, or pull apart your wiring to get it back. Have a look at this page under 'Wound Primary CTs'

http://www.itl-uk.com/introduction-metering-transformers.html

[throbscottle]

Actually found some perfectly adequate clamp meters on eBay very cheap - perfectly adequate for my very occasional and not very accurate needs! Interesting web page - I once read a book about transformer design (about 20 years ago) and realised it was something I was never going to do simply because I didn't know where to get a core with appropriate known qualities to work out the primary turns - for me it was always going to be knowing the basic ratio and thinking of a number for the primary turns - not at all satisfactory.

[aloving95]

Haha I love Photonicinduction and alll the stuff he dose