Author Topic: Identify Douglas magneto mounts  (Read 353 times)

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Offline cardan

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Identify Douglas magneto mounts
« on: 13 Dec 2022 at 06:28 »
There were several means of fixing the magneto to the top of a Douglas crankcase, but I don't recognise these fittings. They're sure to be Douglas because the screws - two for each mount - are 15/64-25tpi [Edit - don't know where I got 27tpi from on the original post!].

I guess they're 1920s? The RA used a similar mount but it had only one 17/64-25tpi screw each side and a removable cotter pin, held in place with a split pin, rather than a fixed rivet.

So, what are they off, and how is the magneto clamped down?

Cheers

Leon
« Last Edit: 22 Dec 2022 at 00:16 by cardan »

Offline cardan

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Re: Identify Douglas magneto mounts
« Reply #1 on: 20 Dec 2022 at 12:34 »
OK, that's weird... I've looked through the various 1920s models and I can't imagine what these come from.

I have no use, so yell if you need them.

Leon

Offline eddie

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Re: Identify Douglas magneto mounts
« Reply #2 on: 20 Dec 2022 at 19:39 »
Leon,
          Do you think these are 'Douglas'? Is there any sign of the 'DK' trademark? 15/64" dia could easily be 6mm - so maybe they are from a mainland European manufacturer (who also had a thing about using odd thread pitches).

  Regards (and seasons greetings),
             Eddie.

Offline cardan

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Re: Identify Douglas magneto mounts
« Reply #3 on: 21 Dec 2022 at 23:59 »
Thanks Eddie - hadn't thought of that! 6mm and 15/64" differ by 0.002", and 1mm pitch (25.4 tpi) and 25 tpi are almost indistinguishable given the length of the screws. So, yep, might be European. Talk about junk that will be in the shed when I die!

All the best for 2023 - it's gotta be better than 2022, doesn't it?

Cheers

Leon

Offline cardan

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Re: Identify Douglas magneto mounts
« Reply #4 on: 22 Dec 2022 at 00:15 »
For comparison, here are the similar items used on an RA Douglas. Love the pins, which are drilled all the way through, then across the end for the split pin. Nice.

Leon

 

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