Member postings for Tony Watson 5

The 20 MM is from the top of the compound slide ie the surface where the toolpost is mounted.

I use T51 holders on my nine inch (4.5 inch centre height) Hercus. The gaps in the holders are 16 mm but the largest practical size for a tool is around 12 mm (insert or cutting edge height). The measurement you need to consider is the centre height from the top of the topslide. I thing this is pretty common top most South Bend clones, including Boxford. The Hercus measures 20mm.

I've found the answer - and a warning to others. Pulling the start winding leads from their terminals has isolated the centrifugal switch. I'm now stuck with fried motor.

Please bear in mind that this was a theoretical exercise to provide a screwcutting facility on one of my unused machines. The Advance is one which I refurbished many years ago as a project. With a fixed carriage nut and a leadscrew clutch it is capable of cutting multiples of eight TPI but needs a reversing facility to cut others. The total expense was envisaged not to exceed the $A15 for the switch. I'm otherwise well covered for lathes with my 9A Hercus, B Type Drummond, A Type Drummond and six mm Lorch.

I do have another motor for the Advance but really need to know what I did wrong before I fry that one as well.

More help required! I've wired up as suggested above - with the addition of an on/off switch at the point marked AC. The inputs were connected to each end of the run winding and thence to the reversing switch. The reversing outputs were connected to each end of the start winding.

The desired reversing of the motor was achieved but the motor ran slightly rough and after about 10 seconds I was greeted with plumes of smoke. I can only think that the start winding has overheated as if the centrifugal switch has failed to open. Or is the run winding somehow causing the problem?

All suggestions/solutions gratefully received.

Bear with me on this one. Do you mean that the the reversing switch should only be connected to the start winding leads? In this case I take it that the run winding will continue to receive current through the start winding after the centrifugal switch cuts it out.

BTW, I have used an extra switch, having little faith in the long term durability of the Chinese contacts.

Small correction. The run winding is connected to terminals THREE and four.

Having decided that a reversing facility on my elderly Advance lathe I purchased at vast expense ($A15) a Chinese reversing switch. This switch is designated QS-15 and has six terminals. The wiring diagram supplied refers to three phase connection and the wiring information on the net is either absent or confusing (to me) in its use of American electrical jargon. Through a process of deduction and insertion of a bridge I managed to wire the switch so the lines in could be continued or reversed at the lines out.

The motor concerned is non-capacitor start split phase 240 volt . Terminals are numbered one to four. Terminals one and three are connected to the start winding and neutral and active respectively. The run winding is connected to terminal four and terminal two has no apparent connection.

It is easily reversed by swapping over the start winding connections. I therefore assumed that reversing the polarity of the lines in would produce the same effect. However, this is not so. The reversing switch is doing its bit but the motor does not reverse. Manually reversing the motor lines in similarly has no effect. What am I missing? Any help would be most appreciated.

Is anyone else in Australia having delivery problems? I reinstated my lapsed MEW subscription on 21 September (to commence with 309) and took out an ME subscription on 14 October. Nothing delivered so far. I appreciated that Australia Post's performance has been mediocre of late but I continue to receive another UK sourced magazine regularly two weeks after publication date. Similarly, MEW back issues I've ordered in the interim have arrived within three weeks. Is the problem with bulk postage arrangement through a third country?

Enquires through the prescribed channels have failed to produce a response - is there anyone out there? My only hope seems to be to have bleat on this forum and hope that one of the respective editors may see it and respond.

Hi Neil

Sorry, I meant MEWs 293 and 294. Were they sent to Australia?

Tony

Neil, can you please advise if copies of MEW 283 and 284 were sent to Australia for distribution by local newsagents.

Thanks

Tony