Member postings for Michael Scott 2

Many , many thanks.

I always meet such nice people on technical Forums

Michaael

Many thanks for a very rapid response

I cannot see or print the whole page

Michael

Hi every one

I have been cutting metal for the Middleton V Twin for more years than i want to own up to and have just reached the stage where I would like to make the eccentric sheave and discover that I do not have the drawing for it

Can any-one help me out please?

Michael

Hi every one.

I thought that it might be informative to relate the story of the successful restitution of working status to my lathe.

I apparently In my search for a reason for a lack of power I had lots of advice, one which was that if the little black button on the back would not stay in when pressed i had probably blown the speed control board and duly bought a replacement (ouch) I found out well into my repair saga that this was probably due to the repetitive small cuts I was doing and the resulting back emf being heartily disliked by the dc motor.

In replacing the board and dealing with the Chinese "birds nest" wiring, apart from some unannounced small differences in the pin locations, I found some loose wires. When I sorted that out, with advice form nice people in the forum, and turned the result was a loud exit of the fuse. Obviously a short circuit.

I was really in trouble now!

Happily I have a good friend who was a specialist in designing power supplies for high end cars infotainment systems.

There are plenty of circuit diagrams on the web for very similar boards and after we had done a fair amount of wire tracing he repaired one of the boards and then simulated the board in a freeby app from the net.

With much hope we re-assembled the lathe electronics and pressed the smoke generator.

Nothing!! Sugar

More wire tracing and limit stop checking. Nothing. Then we checked the stop button. Bingo. Another heart stopping purchase; where I found out that the fault we found is common!. Could this have been my original fault!!!???

Another try with the smoke generator button and the lathe ran for a few seconds and then the fuse blew! We calmly (not) considered the situation, looked for evidence of burning and then put in a bigger (much) fuse.

Bingo.

I have now have put a sensible fuse in and I have a working lathe again.

Two reasons for this post. First, thank you to all the people who so kindly received my calls and emails and at least gave me morale support and those who provided real assistance.

Secondly, to give yet another reminder to even the experts that you should check the obvious first. Did I have power at the pcb? No I did not, Why? Mmmmm.....

Keep cuttng metal.

Michael

Thanks Andrew and for the useful telecon. When Covid allows we will meet.

Bye the way it is a dc brushed motor in my lathe

However as Andrew knows I have discovered a loose red wire hanging below a Siemens block. Pretty obvious the wire has come out of the bottom row of terminals; probably towards the right. I have a photo but cannot yet work out how to include it in this post.

Does anyone with a similar lathe know which terminal on the Siemens block would enjoy being connected the loose wire?

Michael

Eagle eyed people might have seen my first attempt to start a thread. This one is after receiving kind advice.

After some years of great service the lathe part of my wm250 just stopped.

Lots of checking of fuses and limit/cover stops I got me nowhere.

The nice people at Warco sold me a circuit board but after careful ( I think) replacement I still cannot get the lathe to work. I had the variable speed DC motor professionally checked and it is fine.

After the rear fuse blew violently I stopped trying over the winter.

I just repeated the dead short circuit drama

I have not found "smoke" or charring. Nor have I found any loose wires.

I have a photo of the original pcb and there are differences to the new board but I have no way of taking a view on that.

I have the circuit in the IB but the wiring birds nest is a formidable sight for a mechanical engineer especially since I see from other threads that the colour coding is variable. I shudder when I see free floating choc strips. Warco sent me a pcb layout diagram but the lack of reliable colour coding hinders any rational consideration by me.

The question is what do I do next? All suggestions invited!

Is there any one in the Cambridge area that might be able to assist?

Regards

Michael

Hi all

Is there anyone in the Cambridge area who can help get the wiring of a wm 250 sorted out?

It has served me very well until the lathe part stopped. Checked the limit switches and obvious wiring fault possiblities.

The nice people at Warco sold me pcb but that did not work out. As said above there are no colour codes and although I thought that I did the replacement carefully I may have blundered

However I now have a short circuit that blows the rear fuse violently.

Blundering about I notice that the earth lead on the outside of the front fuse has come unsoldered.

I took the trouble to photograph the pcb before removal so will have yet another careful look see.

Regards

Michael

HI

I am a retired engineer, still very active with IMechE, restoring vintage and classic motorbikes.

I have a single garage workshop to hold two bikes the church printer and a reasonable assembly of tools including a lathe with an overhead "mill"

I am building a Middleton inverted vee Twin and have got to the bit where I need to understand the steam flow. I cannot seem to get my head round the input steam flow. Fig 8 of the September 2017 is where I get confused. Is the "mill out steam inlet slot" at both ends of the cylinder ? The result of this does not seem to show up in the pictures. The two steam and one exhaust slots in the base of the cylinder block do not seem to go anywhere!

Please help this old engineer with no steam experience.

Best hopeful regards

Michael