Here is the final segment of the trransformation of the 10speed Red cassette to an 11 speed.
I started by drilling the bolt holes to into the back of the cassette, i used a 3mm bit in the drill press, i then went fractionally bigger to 3.5mm to run a 4.0x0.5mm bolt.
I then ran the 4.0x0.5mm tap through all the holes to create the thread in the actual cassette, though i assumed the cassette wall would be to thin so i made the decision to put nuts in the cassette as extra re enforcement.
The tested my bolts would fit, and cut them to the correct length (they were a smidge to long)
Checked the layout of all 6 bolts now, made sure they were the correct distancefrom the hub to centre the new cog.
Here is a pic of the nut on the inside of the cassette to provide extra strenght under torque.
Next i set out to drill the mount holes in the new cog. this photo shows that i enlarged the holes to fit the new bolts, and i countersunk the bolt heads to keep them out of my spokes. The bolt heads dont sit completely flush but they are fairly close!
This shows the bolts sitting in their configuration, semi flush, in the right spot next step here we come!
I then tested the fit of it, i bolted it to the cassette and dropped a spare freehub into it to check alignment, it was SPOT ON! +1 for accurate measurements and machining!
The cassette bolted roughly together with all 11 speeds!
Next step was to piggy back the new cog onto the cassette by cutting the splined internals out of it. I simply ran a hacksaw through at each point of the cog...
Here is the cog finally sperated, its pretty jagged but as my first prototype it doesnt matter. My next version, on my racier 11-23 cassette will be more visually pleasing!
All bolted up! it sat on the cassette really nicely, really happy with alignment and truth of the spin. It cleared the free hub nicely too!
Mounted on the hub...
Mounted on the bike, and functioning (on the 10 speed lever as i havent started the conversion in the lever yet) Note, that is a wheel not just a hub, i had the wheel spinning so you cant reall see them. It shifts like normal (normal for a tuned to hell rear D) it doesnt move the derailleur into the spokes, i havent had an issue yet. Ill put 200km on the cassette this weekend and see if i can break it!
What i like about my design is that it should be compatible with any existing 10 speed freehub. It fit my American classic wheels, my yishun wheels, and ill start trying them on friends zipps and enves....
I will be bolting the new cog further from the hub next time as an improvement on stiffness and also room between the bolts and the spokes as this could cause issue... Ill keep you all updated any how!