Meddings drive spindle and pulley wheel issue…

[Dokkodo]

I know there are a few meddings aficionados and resto veterans on here, and I’ve posted about mine before…

My spindle pulley has always had issues, from being abused and made a sloppy fit by previous owner i think. I’ve always made do shimming and knocking the key back in periodically as the pulley gets loose after a while and makes a racket before disengaging.

Anyway it’s finally worn beyond useful limits, the grub screw is now threaded and I just need to get a new pulley wheel. However it seems my spindle is 1” bore while everyone else’s seems to be 16mm or 5/8”
Also my spindle has taken a hammering as this looseness has allowed the grub to wear it away in channels quite badly.
The last thing I hope I can fix in the process is about a 1/8th of a turn of freedom between the main spindle and the 1” shaft if possible

What I don’t understand quite is how the inner spindle and the outer shaft relate and whether any of this is possible? Should I just take it apart and see…

 

[ChaiLatte]

What I don’t understand quite is how the inner spindle and the outer shaft relate and whether any of this is possible?

What model Meddings? Do you have an exploded digram (or a link to one so we can all use part numbers in any discussion)?

What you call the outer shaft is a sleeve that transmits the drive from the pulley to what you call the inner spindle. On its outside, its top section is to suit the pulley ID. Then it might grow in diameter a little bit to suit the bearing ID. Once past the bearing, I think (need manual to confirm) it either grows more so it cannot come upwards out of the bearing or has a groove and circlip to serve the same function. On its ID, it has splines to drive the quill spindle.

The sleeve will come out with the bearing (not sure if it has to come up or down) and then you can press the two apart.

Your 1/8 of a turn between the two implies the splines are badly worn. That is possible, but not easy to fix. It also needs pulling to bits to see if it is the inner splines, the outer splines or both that are worn out.

If the damage is only to the outer sleeve, since the drill has spent most of its life going clockwise, it would be possible to re-engineer the sleeve so it works upside down and use the unworn portion of its splines.

Once dismantled, the outside is easy to repair: turn it down on a lathe to clean it up, fill all depressions with weld to build up the surface and turn down to finished diameter. An alternative is to turn it down somewhat, use JB Weld to fill any serious depressions and to secure a metal sleeve in place. Once the glue has set, turn it down to the ID of your pulley and recut the keyway (it might need a shallower-than-standard keyway). The latter method means there will be no heat distortion of it.

For the pulley itself, bore it out, sleeve it and recut the keyway. For that, you can shrink fit the sleeve or loctite it in.

The quill should drop out of the bottom if you release the return spring and remove the pinion that drives it. That is a 10 minute job, not a major operation. Being able ot examine the full length of splines on the inner quill will give you a good idea of the way forward.

 

[Deadeye]

Hi

I have a spare quill including the drive for a Meddings DrillTru II; let me know if interested

 

[redhunter350]

Are these pdf documents of any use? They are for the MF4 Meddings drill