Re: [CAD_CAM_EDM_DRO] A bit off topic - resistance welding

The MEW issues with the bandsaw welder/spot welder article are #41 and #42.

Robert Grauman in Sunny Alberta

> Hello Ian,
>
> Model Engineers Workshop magazine described a combination bandsaw blade
> welder/spot welder that would appear to meet your requirements.
> Unfortunately, I have just loaned out a stack of my MEW magazines, and all

I

> can tell you is the device was described in two consecutive issues

somewhere

> between issue 26 and issue 56. Give me a couple of days, and I can get

the

> correct issue numbers for you, if you are interested. The welder used a

low

> voltage secondary as described in other postings, with a timing device to
> control the weld period.
>
> Robert Grauman in Sunny Alberta
>
> > Hi,
> >
> > I know this is a bit off topic but I know you lot out there have all the
> > expertise in the world!
> >
> > Does anyone have any idea whether it would be possible to make a simple
> > resistance welding set-up for tiny jobs? Basically what I am wanting is

a

> > way of spot welding bits of watch or small clock mainspring material
> > together - spring steel up to about 15 thou thick with welds probably
> about
> > 1.64" diameter. I was thinking it might be possible using just a big

power

> > supply and capacitor like in EDM and discharge this through some kind of
> > 'clip' but I'm not sure how to control the discharge (SCR, Triac?) Also
> I'm
> > not sure about the voltage/current needed - a 24 volt, 10 Amp

transformer

> > with a bridge rectifier and 10,000uf capacitor seems to give an

impressive

> > spark but would this be enough to weld my bits of steel or is it only

good

> > at screwdriver blades? ;o)
> >
> > Any comments would be appreciated.
> >
> > Ian
> > --
> > Ian W. Wright
> > Sheffield UK
>
>