French Barn Find - Buckets of Patina!

A few steps back, but a few steps forward in this chainset swap saga.

The "new" cranks have brushed up well. The stuck NDS bent pedal axle eventually came out with some use from a Camping Gaz blow torch. Oddly, the axle has 16mm flats meaning my homemade 15mm pedal spanner didn't fit. I did not want to grind down a 16mm spanner to make it thin enough - thankfully the Knipex adjustable pipe wrench performed and did the trick.

The old French pedal threads are slightly smaller than the 9/16" standard. I have no idea what
these cranks are, but I used a pair of 80s Look pedals to clean/re-chase the threads. Far too
much time was spent on this but with some force and plenty of lube they now go on squarely. Perhaps the cranks have some weird "inbetween" dimension if such a thing existed????
 

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This photo will explain some things better. The "old" crank as a massive deep recess and sits over a domed DS fixed cup - the chainring position falls somewhere close to an inner ring of a triple, slightly over the BB shell.
 

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My current thinking is to swap the DS fixed cup with the NDS adjustable cup and use the "new" axle.

On paper the measurements look good enough to cobble something together:
- with the new crank, the chainline will still be thrown further outboard by about 1 cm, but
I can't imagine this will be enough to derail the chain.
- there will be no room for the lock ring on the now DS cup, it will be inserted too much with not enough thread.
- I'm thinking of drilling a 3mm small hole in the BB shell at the mid point width of the DS cup, tapping the shell, and putting a 4mm pointy grub screw in to lock it all in position. I did this trick on an utterly dreadful Bianchi years ago to stop the BB undoing itself.
 

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Finally the chainset swap is done. Everything is snug, tolerances are tight, surprisingly
everything is centered, chain line only 8mm off from the original and the cranks spin
round with just a little tight spot which I hope will sort itself out in time.

Judging by the ruined dot punch to get the adjustable cup in the DS, I decided not to
bother with drilling and taping the BB shell for a grub screw to lock it in place - it should
be tight enough and not undo itself.

There are a few microns of adjustability with the domed fixed cup on the NDS via
a large spanner without the need to start bashing out cotter pins etc.

Glad to see the back of this one.
 

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Headset and Forks

....a major turning point for this build. If this goes well then it will be definitely a rider.

The headsets on both frames have been soaking in WD40 for a few days. To get
the lock-nut off the De Dion - Bouton I had to rustle up some accessories for the
lockring hook spanner to fit properly.

A drain pipe off-cut and small piece of wood was enough to pack out the 30mm
diameter to around the normal 40mm diameter.
 

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Re: Re:

The History Man":1quuervs said:
Great progress!

Thanks, had a good day in the man-cave today, nice and mild, and a joy to crack on.

Some would argue it would have been better to go for a ride, but hey oh...
 
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