Point of no return

One kind of point of no return was achieved this week. After spending almost two days impeccably placing the frame on the table situation finally calls for action - it is time to start sawing of the rear parts in order to turn the old swing to hard tail.

When the pendulum stops this precisely over the marker on the table it means that it's time to go. For the reference, below is the frame as it was.

And below here it is how it is now. you can see the idea. The part that was not needed is gone. You can imagine almost straight lines going from the axle plate on the right hand side to where the frame ends. 

You probably have noticed that I tend to write down the stuff I didn't know - which is almost everything. But honestly, I found this interesting little detail: Below is the cast iron piece attached to central post of the frame. Through it, the frame tube goes and when it was sawn off with and angle grinder like this it should come off. Once again I have to take my hat of for my friends helping me out. His precision is immaculate as he first saw off precisely the welding seam without so much as touching the material of the original tubing. In the pic below, you can see a seam between what is left of the tube and the cast iron piece and notice they are no more welded together.

From this point a nail punch was applied. Finding a correct angle and gently tapping it the last piece of tubing comes off and we are left with rather intact nesting for a tube. We do not know for sure yet, if the new tubing will precisely fit to this cradle, but it can be adjusted if so needed. And we can always discard it completely if it is not needed, but nothing is lost and everything can be used. 

The next step is to be sure we have enough room for the chain between the wheel and the frame tubing and making sure we have a proper distance between the rear axle and the frame. The proper distance is determined by the size of the rear wheel and the criteria, that if rear axle is too close to the frame the wheel will touch gearbox - which obviously is not an option. Being too far away is not that critical but it will impact the visual appearance of the bike quite dramatically. 

In the original setup the distance of rear axle from a reference point is about 34cm and we think we can squeeze the same measure to 32cm effectively shortening the wheelbase with 2cm which also makes the rear more tightly packed looking. It makes sense for the style I'm after, but were I building a chopper, I'd probably bring rear wheel a centimeter or two backwards for pertaining a geometry. For today I learnt that chopper should make a wide "A" shape letter where front wheel and rear wheel are equally far from the top of the steering axle. This makes sense - google images for "swedish style choppers" and you will see it. I'm not going for a chopper so it's not relevant for my case but it's nice observation that makes you look long bikes tiny bit differently.