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Dave

2024-06-11, 20:02:05
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Dave

2024-06-08, 18:30:04
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Dave

2024-06-07, 02:13:36

Dave

2024-06-03, 08:23:05
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Duncan has just listed his green and cream 1957 Dragonfly for sale with spares and documents.

Dave

2024-06-02, 08:34:05
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Dave

2024-06-01, 18:33:27

Dave

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Douglas Dragonfly make a Switch contact tab

Started by BrmBrm, 10 Jan 2019 at 20:20

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BrmBrm

Next phase of the Dragonfly switch replacement. A contact tab.

I need to make the contact tab that goes onto the switch mounting stud.
That is the one that would be contact number 9.
On the circular central switch area there are different contact bands.
Which of these should contact 9 bear against?
It presumably fits on the stud under the nut?
What shape should it be?
Like one of the other contact tabs?
Any help appreciated
Many thanks.

andy1303

I had a look on my bike today, and while it was obscured by the rest of the switch, it looked like there was a crimp ring terminal on the switch and I think it was on position 9. Mine was one of the awful blue insulated crimp variety, but I'll probably replace it with a proper brass ring terminal at some point. Would that be what you're looking for?

Andy

Red

Hi Brm

Terminal 9 is connected to the resitor for the ignition warning light in the Miller ammeter. On my Dragonfly I don't have the Miller ammeter or the ignition warning light so I disregarded this connection. The stud for teminal 9 is also used for one of the small "L" clamps which secure the switch in the headlamp housing. Therefore if you are going to run a wire from terminal 9 to the ignition warning light resitor you will need to make sure the "L" clamp is well insulated from the inside of the headlamp housing otherwise when you switch on the igntion you are likely to get a short to earth.

Roy

BrmBrm

#3
Thanks Andy 1303 and Red.
Sorry but that's not the info I need.
Stud number 9 should have a brass springy contact of some kind that bears against some  brass rings that wrap around the central shaft of the switch. That's what I am trying to replicate, but don't know what it looks like, or which of the brass rings it contacts.  I don't have one so can't describe it to you. But presumably it's similar but not identical to the ones on the other  terminals.
It's what I need to make, but don't have one to copy. And I don't know how many of the brass rings it should contact.
But thanks any-way.

Roys rider

Hope these help. If this is not what you want let me know. There should be 3 photos of a brand new switch. Apologies it is not easy to focus on the right bit. ( has the nut on it.
I made a mistake and used locking connectors which are great as they wont fall off but are a pig to get off so I would prefer not to have to take them off but will if that will help.
Peter

Roys rider

and 2 more photos.

BrmBrm

The photos are suberb, RoysRider.
That's exactly the tab I have to repliicate,
(and tighten an existing terminal tab on terminal 5).

Please don't dismantle anything more, in case something goes wrong!
Bye the way, yours is a new switch - where did you get it from - are they still available.
Many thanks,
Dave

Roys rider

It was left to me (with another d/f) by my father who bought it in 1974 from club spares - not sure if they have any left. ;-)
Peter

BrmBrm

Looks like I should be able to modify the fuse holder from a 13A plug, flatten one of the folds, drill a hole for the douglas switch stud, cut off the excess material, and thereby make the missing tab and attach to the stud 9.
I stripped the switch to re-bend contact 5 which is now OK.

I still have another question that I'm going round in circles with -
When replacing the switch cover (with the 2 studs) onto the switch, which connector should coincide with OFF on the cover, Number 8 or Number 4?

Thanks for any help.




Roys rider

As I see it, there is no difference. Without the key in, the knob can rotate 360 deg and with the key in it is restricted by the switch detentes OFF, then IGN, SIDE and HEAD to the right and EMG to left. This happens which ever way you fit it. I'll make sure later but I want to fit the timing cover today.
Peter

BrmBrm

#10
Thanks for your reply Roys Rider.
Yes the switch cover/bezel will fit 180deg either way onto the switch, so I have to figure out which is the way as shown on the wiring diagram No. 2166.
Bearing in mind the existing wiring I have on the bike ia all incorrect or missing.

The best way I can ask my question is "referring to Wiring diag. Drg No. 2166, which of the terminals shown aligns with the OFF position?



eddie

On my switch, terminal 8 lines up with the 'off' position.

  Regards,
                  Eddie.


eddie

This is a drawing that has been about for many years (possibly, even from the factory), but has an error on the internal wiring of the alternator. The inside of all 6 coils are connected, but the outsides should be connected as banks of 2 and 4 coils - the outside connection between 4 and 6 o'clock should not be there!

  Regards,
                 Eddie.

BrmBrm

Eddie, Jonathan and Roy and all.
That's great, I'll go with terminal 8 to OFF.
That's the switch finished! Now I can use Wiring diag 2166 to wire the bike.
Many thanks to all.

Roys rider

Sorry, I should have checked first then written a recommendation. I have now had a look and I agree with what the others have said. In fact the edge of the key fits in a little groove at the BACK of the centre pillar and the switch knob.
Peter

BrmBrm

Ah, I see. The slot is not symmetrical. So the key and knob only go on one way. And the contact tab only goes on screw stud 9 because the contact band is not 360deg. So it's likely the switch can only be assembled one way.
My switch knob is a modified one, ex BSA I think, which I cut the key slot in, symmetrically - oops!

Anyway I now know that the moulded OFF aligns with terminal 8.

By the way, if you did fit your timing cover, did you manage to satisfacorily seal the generator wiring. I managed to do that a few months ago using a variety of grommets.
Best wishes,
Dave
-

Roys rider

As with most of these jobs something stops it working. This time the timing cover just would not go on. I took the alternator off and the beautifully sealed cover to find that the crankshaft bush was too small to go over the crankshaft. So now I will have to take the bush out and reamer it. One step forward 2 back. There is a grommet for the wire in the cover however whether it will seal is another matter.