Home made transformer

[Tim]

Thanks chaps.

[Tim]

Thanks for comments.
I’ve had a quick look at the ‘scope & at first glance a second dedicated transformer for the 950 volts will be a tight squeeze. However there is some sort of rotary switch and a “ d” socket on the back to provide an output to a plotter. I don’t see myself ever using the plotter facility so I can remove it to mount my transformer, should I so decide.
I think a scrap wall wart will yield a suitable transformer for this option, with the added bonus I can have some fun re-winding the secondary.

[Tim]

I have also been swotting up on cogs and gear ratios etc. for when/if I come to make my own winder. Cogs, wheels and the like seem easily available.
I have what I hope will be a suitable motor taken from a 12volt cassette mechanism. It’s rated at 2400 RPM. It will need gearing down of course, which will help boost the torque at the final shaft that will hold the bobbin. Some experimentation is called for. If only I could find my Meccano.

I have also seen some of the double insulated PVwhatever wire mentioned earlier in the thread for sale on E-bay. 36 SWG seems to be the smallest size, which may mean my transformer might have to be larger than one might expect, but would , in turn be less fiddly to do.

[Ed_Dinning]

Hi Tim, scrap printers are a good source for gears and cogs
Wires.co.uk supply grade 2 solderable copper wire on spools from 50g upwards

Ed

[Diabolical Artificer]

Tim, I have quite a few motors if you want any, mostly pulled from printers as well as motor and spindle from a failed tfmr winder you can have FOC..

Re tfmr winding, make the tfmr/core/bobbin bigger than calculated, one can never achieve 100% calculated fill.

Andy.

Stepper motors are good to use, a simple programme can control speed and direction, two could be used for a wave winder, no gears required. Parts do do this are inexpensive and available from robot maker places.

[vinrads]

My attempt of a homebrew winder yet to be finished, using an old 12 volt drill ,the speed control and reverse re wired into a control box ,I have just bought a magnetic impulse counter which I will fit on to the chuck. Mick

[Tim]

Thanks Andy, Mick & Merlin.
Yes, I have been looking at robot maker suppliers for bits. There seem to be all sorts of motors as well.
I think the DC route is better for motors, as it will allow reasonably easy speed control and reversibility. I’m a bit wary of anything too powerful, due to a possible risk of snapping thin wires.
A car cassette player motor may not seem very powerful, but it will be geared down by a few multiples of ten, so the torque delivered will increase by a similar amount.
I’m looking at a belt drive between the motor pulley and the first gear. Hopefully this will be enough to provide enough “ ommph” but would slip if anything went wrong. A sort of mechanical fuse if you will.

If I do end up using a separate transformer for the 950 volts, it probably will be bigger than expected as I will probably want to use insulation between each layer and the double insulated copper wire I plan to use is probably thicker than that originally employed. Then there is the efficiency factor as well.

I have the basic plan in my head, now all I need is the time to do it.

[Diabolical Artificer]

Hi Tim, here's the bobbin winder I mentioned plus an assortment of motors. The bobbin winder is a 240v jobbie i think,the "housing could be done a lot better & needs a clean. The motors are various from printers so mostly 6/12v plus there's two big 12v jobbies, There's also two or three steppers as well as some belts. I also have various cogs etc somewhere too. I can put together an assortment box if you wish.

Andy.

PS pics continued in next post.