Tom Senior power feed fixings help

[choochoo_balooParticipant @choochoo_baloo]

[choochoo_balooParticipant @choochoo_baloo]

I am reassembling my Senior M1 saddle after a thorough clean and re-oiling. I must have been on 'autopilot' when disassembling, since I just realised I don't know what the circled torpedo pin in photo 1 and adjacent hex bolt do.

Photo 1 is the lever to engage/disengage the dog clutch from the power feed gearbox to a key way on the table x axis leadscrew.

Close up of them in photo 2. (The grub +spring + ball sit in the front hole and hold the lever in 2 indent poisitions for engage/disenage).

Photo 3 just shows one of the 2 flats on the lever shaft, that this torpedo pin must bear onto.

Thanks in advance.

[Kiwi BlokeParticipant @kiwibloke62605]

The 'torpedo pin' is the table knock-off plunger which, when pushed down by the (adjustable) knock-off dog on the front face of the table, throws the table auto-feed out of engagement, by turning the black-knobbed lever. Sorry, can't remember what the screw does.

Most of the M1 saddles I've seen have had the table feed lever supported by a cast-in boss on the saddle, not by, as yours seems to have, a bolted-on plate. The knob's shaft also sits near the bottom of the saddle, whereas yours seems to sit nearer the top (perhaps perspective distortion by the camera?). A late variant has the table dog bear directly on a pin sticking backwards from the hand lever, which is of flat section, and supported by a bolt-on plate.

Because of these differences, I think that your machine is actually a 'Junior' – just a little smaller than the M1.  Am I horribly mistaken (it has been known – according to my wife…)?

Edited By Kiwi Bloke on 11/01/2020 23:27:09

Edited By Kiwi Bloke on 11/01/2020 23:30:44

[choochoo_balooParticipant @choochoo_baloo]

Many thanks Kiwi. I've replied inline below:

Posted by Kiwi Bloke on 11/01/2020 23:10:50:

The 'torpedo pin' is the table knock-off plunger which, when pushed down by the (adjustable) knock-off dog on the front face of the table, throws the table auto-feed out of engagement, by turning the black-knobbed lever.

ok that makes sense. So that's why one of the 2 sliding (approx 1" cubes) knock off dogs on the front face of the table, has a convex bottom face – to ride over and depress this plunger?

Sorry, can't remember what the screw does.

I reckon I've now got it. My "Nature" standard sketch below (!) explains it. That hex bolt must bear against its flat to ensure the lever isn't push over too far. This therefore limits the L/R sliding of the dog clutch. But why does this need limiting? Second below is a more helpful photo of the complete saddle innards…what do you think?

 

…I think that your machine is actually a 'Junior' – just a little smaller than the M1.

Defo an M1; stamped M1 on the CI column and on the brass serial plate on the saddle. An M1 restoration article I've read does stress there were minor variations in fittings within the same models. So what you described isn't unusual Senior practise.

 

Edited By choochoo_baloo on 12/01/2020 00:15:39

Edited By choochoo_baloo on 12/01/2020 00:16:11

Edited By choochoo_baloo on 12/01/2020 00:31:05

[Kiwi BlokeParticipant @kiwibloke62605]

Yep, you've got it. I'd imagine that the screw is there to limit the arc of movement of the lever to something that looks and feels 'right' rather than to limit the movement of the dog clutch per se.

Interesting to know that it's an M1. So that makes three types of saddle and two types of power feed mechanisms – at least. Yours must be a very late model. With these old machines, one sometimes wonders whether two were ever made the same…

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