Author Topic: 1913 2 & 3/4 clutch drive plate keyways mangled  (Read 2821 times)

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Offline phil_h

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1913 2 & 3/4 clutch drive plate keyways mangled
« on: 24 Oct 2012 at 14:14 »
I had big problems in the Banbury run this year as my clutch stopped working after it came loose :(
The keyway and key were in a bad state but I bodged up a repair by the roadside using wire and pvc tape to hold it all together, and just didnt use the clutch any more !

The time has come for it to be fixed for next year - has anyone got any experience to offer please ?
« Last Edit: 08 Jan 2013 at 19:17 by phil_h »

Offline phil_h

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Re: 1913 2 & 3/4 clutch drive plate keyways mangled
« Reply #1 on: 08 Jan 2013 at 19:16 »
I'm progressing, but have still to find a supply of woodruff keys to suit.
Anyone got any contacts for 4 off of 3/16" thick x 1/2" long x 3/4" diam (probably) ?
I only have 2 slightly mangled keys, but there are cutaways for 4, so I think half my problem was tryng to get it working by the roadside with just 2 keys.

Its entered in the Pioneer and the Banbury already, so I'm getting excited now :)

Happy New Year to all
phil

Offline eddie

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Re: 1913 2 & 3/4 clutch drive plate keyways mangled
« Reply #2 on: 08 Jan 2013 at 20:25 »
Phil,
      There were 2 types of cone clutch fitted to veteran Douglas 2's. The early type was smaller and was housed within the gearbox pulley - the later type, being larger, was carried outboard of the pulley, but stil part of it. The LDMCC's 1912  has the early type - some years ago the cente boss of the cone split - down the keyway. I effected a repair by clamping the 2 halves together and machining a register at the end to accept a retaining ring. This then held everything in place while I turned the rest of the boss to a true diameter. I then machined up a steel sleeve and pressed it onto the boss (having removed the retaining ring). As far as I am aware, the clutch hasn't given any further problems.
     Regarding the supply of keys - some of the older sizes are not easy to find these days. It is often quicker to set up a bit of mild steel in the lathe and part off a couple of discs of the required diameter and thickness and then saw out sections to the required depth.
    Whilst we are on the subject of keys, Mr Douglas favoured the use of 2 keys on taper fit sprockets/pulleys - this is bad practice - the taper should do the driving, the key just keeping everything in place while the nut is tightened. The addition of a second key at 90 degrees to the first makes it almost impossible to get the taper to seat correctly - thus making the fit less effective.

     Regards,
                   Eddie.

Offline phil_h

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Re: 1913 2 & 3/4 clutch drive plate keyways mangled
« Reply #3 on: 08 Jan 2013 at 21:33 »
Here is my clutch.
It slides on the gearbox output shaft, with the spring behind the large cone.
The friction material is riveted to the tapered outer lip of the black-painted inner 'cup'.
There are 4 keyways in the output shaft, 2 in line with each other 180deg apart, so the black 'cup' slides on them all.
Doesnt sound at all like what you describe Eddie !

« Last Edit: 12 Feb 2013 at 20:09 by Dave »

Offline eddie

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Re: 1913 2 & 3/4 clutch drive plate keyways mangled
« Reply #4 on: 09 Jan 2013 at 07:30 »
Hi Phil,
          Your clutch is the later type. It is much the same in design as the earlier type, except that, from your description, the cone slides on 4 keys instead of just 2 in the earlier design. The boss that split on the Club's machine is inside the main spring, and had allowed the cone to tilt and jam.

Eddie.

 

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