1908 Dennis Truck

[BenHawkins]

I have been working on the flywheel/clutch, the flywheel is built up of many parts so the first task was cleaning things up. This ring fits on the engine side of the flywheel (I believe described as "balance weight" in the parts list).

The balance weight bolts to a "Plate" attached to the flywheel. The balance weight had to be supported on some blocks of wood whilst I fitted the "Plate" to the crankshaft flange with the six bolts that came with the engine.

The clutch engagement force is supplied by a large, stiff square section "Spring".

I cleaned up the ball thrust race and it all looked servicable.

A bronze "Spring Plate" adapts the bearing to the spring.

The "Male Part" has a leather friction lining, this was treated with Neatsfoot oil as it had dried out over the last century of neglect. There are small bronze fingers between the casting and the leather to promote a softer engagement of the clutch by lifting the leather slightly.

[BenHawkins]

I stuck the bearing and spring plate into the "male part" with plenty of grease. so I didn't drop them out during assembly.

Then put the spring and male part in place, securing with cable ties whilst I prepared the female part.

I didn't get any photos of the process (I was covered in grease), but I had to use clamps on the male part to sufficiently compress the spring and enable the nuts to be fitted.

I was missing one bolt so I made a replacement to match the ones that survived.

The clutch is released by pushing the male part forwards, these "phosphor bronze slippers" fit into a slot in the male part.

 

[BenHawkins]

The clutch shaft brackets were more of a challenge. Nothing lined up particularly well, so I set about getting the alignment right and bolted it up with 1/4" bolts, then filed out one hole in the brackets at a time until I could replace it with the a 3/8 BSW set screw. I still need to make up some old pattern bolts and slotted nuts to replace the modern set screws.

I had been trying for several years to find someone to rebuild the Bosch D4 magneto; they are quite distinctive so I didn't want to fit an alternative. Although several companies had agreed to take it on, after dropping it off I was always called back to collect when they saw how square (and therefore awkward to wind) the armature was.

Well, this week I got it back with a new winding. Although it was not cheap, I was dreading tooling up for the job (and quite probably ending up with an unreliable magneto) so it is quite a relief.

 

 

[Scrunt & Farthing]

Ben,  Can I asked who you used for the mag-repair?   I have made enquiries of several mag firms but they all seem it terribly busy, or do not get back to you (which does not inspire confidence!).

Thanks

Dave 

[andypugh]

56 minutes ago, Scrunt & Farthing said:

Ben,  Can I asked who you used for the mag-repair? 

I rewound my own, and it very nearly works 🙂

It is actually something that you can consider doing yourself, I found this web page very useful. 

http://www.brufnut.de/WORKSHOP/LUCAS/lucas.htm
 

(It's an old page, but then magnetos are old tech)

Here is the tale of my own rewind: https://bodgesoc.blogspot.com/2014/06/neracar4.html

[Asciidv]

Andy, at a rough guess how many volts/layer did you think you were generating? What distance did you set your safety spark gap at and were you able to see/hear it in action. I must admit I like the Kapton/polyamide tape too!

[andypugh]

58 minutes ago, Asciidv said:

Andy, at a rough guess how many volts/layer did you think you were generating? What distance did you set your safety spark gap at and were you able to see/hear it in action. I must admit I like the Kapton/polyamide tape too!

I set the safety gap to 6mm. I actually had to add a safety gap, there didn't seem to be one originally. 

Currently I have a feeling that I am limited by the magnets, they are just not very sticky. I have had a number of tries are remagnetising: https://bodgesoc.blogspot.com/2017/05/magneto.html

It has ocurred to me that the kapton tape might seal at the edges and be counterproductive for the resin vacuum infusion step. 

My magneto appeared to work just fine when first rebuilt, but works less well now, and it is hard to see what might cause a deterioration whilst still leaving continuity.