Help Dismantling a Super 7

[Brian OldfordParticipant @brianoldford70365]

[Brian OldfordParticipant @brianoldford70365]

Can anyone advise me if I've overlooked something or if there is anything missing from the exploded view G of the S7 on/in the Myford website/manual.

In preparation to fit a stepper motor to drive the leadscrew for the Electronic Lead Screw I'm trying to measuring up to make the bracketry for the motor. To do this I need to remove the Change Gear Quadrant (Diagram I/D G52; Part A4736). I have removed the two 1/4 BSF nuts along with washers from the studs (Diagram I/D G53; Part A4725). Is there anything else holding the Change Gear Quadrant? It rotates freely around the leadscrew but I'm unable to withdraw it away from the L/H Leadscrew Bracket Assembly (Diagram I/D G45; Part 74/1134/1).

I'm hesitant to try anything concussive at this stage.

https://www.myford.co.uk/acatalog/info_685.html

[John HaineParticipant @johnhaine32865]

Consider putting the stepper at the other end.

There are tapped holes along the back of the bed to which you can fix a bracket with timing belt drive to a pulley replacing the handwheel.

[Brian OldfordParticipant @brianoldford70365]

Posted by John Haine on 08/09/2019 20:18:07:

Consider putting the stepper at the other end.

There are tapped holes along the back of the bed to which you can fix a bracket with timing belt drive to a pulley replacing the handwheel.

Thanks John. I had considered that and may yet end up resorting to it. However at present I'm pursuing the idea of fitting all the gubbins; Stepper Motor, Rotary Encoder etc. inside the change-wheel housing.

It still doesn't explain why the darn banjo won't come off!

[John PParticipant @johnp77052]

Just had a look at mine ,took off the 2 nuts and washers and the key from the lead screw and it comes away with no problems ,there is not much clearance between the slots and the studs and it may over time formed a small burr on the edge of the slots which is catching on the threads on the studs .

John

[Brian OldfordParticipant @brianoldford70365]

Posted by John Pace on 08/09/2019 20:49:53:

Just had a look at mine ,took off the 2 nuts and washers and the key from the lead screw and it comes away with no problems ,there is not much clearance between the slots and the studs and it may over time formed a small burr on the edge of the slots which is catching on the threads on the studs .

John

Thanks John. I'll take another look at it tomorrow morning and let you know if it is as simple as that.

[Brian OldfordParticipant @brianoldford70365]

Hi John

I didn't manage to get back to it until late afternoon.

However I had had Success!

I inspected the studs for the burr you suggested but could n't find anything. Even after removing the studs completely the thing still wouldn't budge. With that I decided to remove the rear plate of the change-gear housing, the left hand lead-screw bearing and the banjo as one lump by removing the 3 x 1/4" BSF fixing bolts.

With the lead-screw bearing gripped in the soft jaws of the vice a few very gentle taps to the banjo released the spigot that is concentric with the lead-screw from the bearing body.

Job done.

Now to see if I can mount the stepper motor.

[John PParticipant @johnp77052]

Brian good to see that the problem is solved with all parts intact.

Your post struck a chord as i had in the past experienced this similar
problem which was solved how i had described.
It was some time ago back in 2005 when i cnc'd my Myford 7,it took
me 4 years to cnc my Dore westbury mill and about 3 weeks to do the
Myford .
Seen here in the photo the stepper motor is mounted at the back of
the machine ,i made a complete new rear bracket for the lead screw with 2

preloaded ball races for the lead screw.
Rear mounting the stepper motor retains all of the functions of the manual
machine.
John

[Brian OldfordParticipant @brianoldford70365]

I'm working up a bracket to mount the stepper motor inside the change-gear housing. I'm making my Mk1 arrangement with the motor driving the LH end of the lead-screw via a pair of skew gears. That way I'm hoping I can get the 120mm long motor inside the housing.
If there's any interest I'll post updates as I proceed.

 

Edited By Brian Oldford on 11/09/2019 19:27:47

[Enough!Participant @enough]

Posted by Brian Oldford on 08/09/2019 19:58:37:

In preparation to fit a stepper motor to drive the leadscrew for the Electronic Lead Screw

Which particular Electronic Leadscrew version are you fitting, Brian?

[Brian OldfordParticipant @brianoldford70365]

Posted by Bandersnatch on 12/09/2019 01:39:38:

Posted by Brian Oldford on 08/09/2019 19:58:37:

In preparation to fit a stepper motor to drive the leadscrew for the Electronic Lead Screw

Which particular Electronic Leadscrew version are you fitting, Brian?

I'm keeping my options open just for now because I want to prove that my chosen method of discreetly driving the lead-screw is satisfactory.

(I've yet to decide exactly how I'm going to mount and drive the rotary encoder).

At this stage I'leaning towards the one that's serialised on Youtube by Clough42 starting at **LINK**

He's fully open sourced the source code should anyone what to tweak it for there own use.

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