Wright writes.....

[1471SirFrederickBanbury]

4 minutes ago, PupCam said:

 

Looks more like a failed one-piece plastic moulding to me.    However, you are correct in stating it's a poor design - one that can fail in such a manner and cover the naked user with boiling (OK, very hot) water is a poor design.

 

 

Does a Bendix clutch not rely on a) inertia of the driving component and b) a thread or helix to provide the longitudinal movement of the driving component required to provide the necessary engagement/disengagement with the driven component when the driving component starts to rotate (a rhetorical question)?       As a consequence they only work in one direction and so will not drive in reverse because of the "handing" of the helix (in whatever form).     This could be a draw back on a locomotive I would have thought .....

 

I can't help thinking that to get a suitable bidirectional, Bendix clutch that provides any benefits and perhaps more importantly introduces no drawbacks will be extremely difficult particularly in the smaller scales where mass, spring rates, friction and inertia do not scale linearly.   However, I admire your thinking and eagerly await news of the results of your experiments.

 

Alan

 

 

On the first point, I don't know of any plastic breakages in a one piece design that is that perfectly circular, which why i think it is 3 pieces

 

On the clutches though, the solution is easy.  Just have a clutch plate on both sides of the threaded collar, ditto for the axle.  The only difference between this clutch design and a normal final drive for a gearbox is that the final drive gear is threaded in the bore, engaging with a threaded collar with a clutch plate on each side (forward being machined as a single piece with the collar, the other being threaded on with Loctite 603), with the axle inside the collar, itself fitted with a couple clutch plates.  drive forward, and the clutch plates on one side engage, reverse, and the other side engages

[Chuffer Davies]

31 minutes ago, 1471SirFrederickBanbury said:

On the first point, I don't know of any plastic breakages in a one piece design that is that perfectly circular, which why i think it is 3 pieces

 

On the clutches though, the solution is easy.  Just have a clutch plate on both sides of the threaded collar, ditto for the axle.  The only difference between this clutch design and a normal final drive for a gearbox is that the final drive gear is threaded in the bore, engaging with a threaded collar with a clutch plate on each side (forward being machined as a single piece with the collar, the other being threaded on with Loctite 603), with the axle inside the collar, itself fitted with a couple clutch plates.  drive forward, and the clutch plates on one side engage, reverse, and the other side engages

How do you get drive from the motor to the clutch plate on the reverse of the threaded collar?  I can’t picture how this would work.

[1471SirFrederickBanbury]

15 minutes ago, Chuffer Davies said:

How do you get drive from the motor to the clutch plate on the reverse of the threaded collar?  I can’t picture how this would work.

the clutch plates connect and become constrained.  Because the threaded collar cant move sideways anymore, it must rotate with the final drive gear. 

[dibateg]

Congratulations on your great news Tony and Mo!

 

Yes - 92204 was one of the three. 

 

Regards

Tony

[polybear]

4 hours ago, Tony Wright said:

Not quite so much progress on the DJH A1s (becoming grandparents to twin girls last week rather takes up time!). 

 

 

Congratulations to you both Tony & Mo - what will be their first prezzies?  Ah yes....Soldering Irons.....🤣

[ROY@34F]

4 hours ago, Tony Wright said:

Not quite so much progress on the DJH A1s (becoming grandparents to twin girls last week rather takes up time!). 

 

 

Congratulations to you both Tony and Mo . Two little girls . Absolutely delightful , So pleased for you both .

Best wishes ,  Pat and Roy .

[Bucoops]

Many congratulations to Mum and Dad and of course yourself and Mo.

 

So - are you Grandad, Grandpa, Gramps, Sir, or something else? 😀

[melmoth]

18 minutes ago, Bucoops said:

Many congratulations to Mum and Dad and of course yourself and Mo.

 

So - are you Grandad, Grandpa, Gramps, Sir, or something else? 😀

 

My Grandpa was generally referred to by his wife, daughter, and son-in-law as 'that b*gger in the shed'

[Woodcock29]

6 hours ago, Tony Wright said:

Not quite so much progress on the DJH A1s (becoming grandparents to twin girls last week rather takes up time!). 

Congratulations to both of you, Tony and Mo.

Andrew

 

[lezz01]

Congrats Tony and Mo. 

Regards Lez.

[LaScala]

8 hours ago, Tony Wright said:

Not quite so much progress on the DJH A1s (becoming grandparents to twin girls last week rather takes up time!). 

 

 

 

Why DJH provides 'blind' chimneys is a mystery (easier to cast?). Meaning they have to be drilled through.

 

The chimneys must be soldered in place for this procedure - glue, any glue, will just fail under the pressure (I know!). The process is best done by hand, in stages.

 

 

Cabs on/complete as well - always an early stage because the cabsides are very vulnerable. 

 

 

Two Wrights don't make an A1?