Member postings for john carruthers

In the plans Brian suggests taking the motor off the drill press temporarily and using that.

I may build a better spindle later with ball races and a more powerful motor.

The minute wheels...

Yesterday I started on the minute and reverse minute wheels. All kinds of bother with the spindle, belt too loose it slips, too tight it doesn't turn (or with reduced power).

In the end I removed the drive pulley and clamped a 1200W drill on the end of the shaft.
What a transformation, now it cuts full depth at a single pass, 32T Mod1 wheel cut in a couple of minutes, best result yet.

Now that I know it has a chance of working I shall put a bit of effort into the finish of the parts; cross out the wheels and spot the flat parts.

**LINK**

Today I made the foliot and it actually ticks.
A bit erratic yet but quite encouraging.

A discarded roof slate screwed to the wall of the shed over the lathe and a bit of chalk for jotting numbers and reminders. I live on aprox 12 billion tons of chalk so no shortage.

I have to make hay while the sun shines Neil, might be back on the morphine tomorrow

Hi Zuji, I have an sc3 and can, when necessary, work to +- 0.01mm with a sharp tool. If a better fit is required then grind or file and paper it.
What will you be using to measure the parts? my calipers only claim 0.005mm (if they are to be believed) and my mic was good to 0.0005" but it's had a lot of use since then.

>>but no way to 'borrow' a few as security is tight<<

There is always a way

Today I made a few screws and the verge/pallet.
Next the verge support.

It's coming along John thanks, I planted the train today and it runs with a piece of brass tied to the cord as a weight.
Next some tidying up, then the verge/foliot.

deleted post, I see you've sorted it.

Edited By john carruthers on 25/06/2016 17:01:17

I spent most of today making shiny screws...

Try putting them on a bed of silver sand or brass swarf, then heat slowly from underneath.
Get the steel really clean, no grease or finger marks. I still got a small patch on one of the plates but after the third attempt said 'good enough'

I've fettled a few mounts that use a friction drive rather than the traditional wormwheels. No backlash, but a small chance of slipping under acceleration, which can be ramped up and down of course.
One chap in Ireland has used a large diameter small pitched toothed belt. Then there are the 'caterpillar' drives, sectors, drum/wire etc...
So many solutions to the same problem

I find the worm bearings on mass produced mounts a major source of PE, better quality bearings or angular contact bearings can make a measurable improvement. Also worm end float needs better control.
A lot of worms have their cetre holes so a conical set screw on one or both ends can help.

The belt conversion kits are a good idea too, doing away with the spur backlash.

Edited By john carruthers on 24/06/2016 08:12:48

>>of my working life & the silverers were very secretive about the mixes for coloured silvering<<

Seemed to be widespread in the glass trade. Mr Stanners who set up Folkestone glass paid a lot of money for the secret for silvering.
Even had one cutter who knew how to cut holes in wired, but shut everyone out while he did it. (simple enough once you now )

How apprentices were supposed to learn I don't know.... ??

I made a start on the minute pinion today.

Old fridge compressor? they are very quiet.
They don't produce a huge volume but quite a good pressure eventually.

I tested my first wobbler on the coffee maker steam outlet.

Edited By john carruthers on 18/06/2016 07:44:17

Very true Brian, we used them extensively in the glass trade for edge grinders etc. One of my jobs was to thrash them on the bench then give them a good hammering occasinally to loosen the glass dust which set like concrete.
A bit more robust than my current drive, light duties only.

I may have a go at a pinion today.
Progress so far...

Edited By john carruthers on 17/06/2016 07:50:40