Penny Farthing backbone

I just picked up the backbone for my penny farthing bike. Now I have all main parts in my workshop.
The backbone is still in its 'raw' state - it is oversized and will be cut to correct length later on.

Bigwheel rim!

Finally! The task I thought the most difficult of this project has just been finished: it took two hours and 4 grinding disks, but the bigwheel rim is done!

As with the small wheel, the result is quite satisfactory! Some deburring, but nothing to worry about.
For people trying to use this technique to cut a rim, I have the advice to leave some material at regular intervals when cutting the second side of the rim. I noticed that due to tensions on the wheel, it could be that the cut 'collapses'. So if you don't cut the rim completely through every 50 cm or so, this is a good way of anticipating this problem. You can carefully cut the reminding material at the end.

Recently I'm having doubts with the hubs. Not only am I a bit suspicious about the material (aluminium), I also don't know yet how to attach the hubs to a central axle. The axle must be aluminium too, but I would like to stay with steel. I have some idea's developing in the back of my mind. More on this later.
Time to sit back and enjoy the result so far... with a glass of whisky!

Niples + hole simulation

Just back from the hardware shop with the nipples.

I hope I will be able to finish these soon. I'll try to do about 10 each day so I won't get bored.

I did a little simulation for the niple holes in the rim:

For the nipples to come out flush with the bottom of the rim, a hole of approximately 6mm should be sufficient. It's the chamfering of the hole that is more important.
(Note the inclination of the nipple with regard to the centre of the rim!)

Rear wheel rim holes (continued)

Another picture of the rear wheel with the pattern of the holes for the spokes:

I made the pattern like this: I used a strip of paper which I put around the rim. This gave me the correct circumference. I removed the strip and divided it into 20 equal parts and then put the strip back on the rim and transferred the marks from the paper to the rim.

First I was thinking to use a piece of yarn to do this, but yarn stretches and paper does not.

The bolts I would like to use as nipples are these (I found a couple in my drawer - I will need to buy the other 75 soon enough):

As you can see, the niple standing up already has the M3 thread cut on the inside for the spoke.

Rear wheel rim holes

After using a punch to mark the hole position, I started drilling the holes for the nipples that hold the spokes:

I drilled with a drill of 5mm, but this will be drilled to a bigger hole later on. The nipples will be made of M5 stainless bolts with a flat head. I will buy these very soon.
The rear wheel will have 20 spokes, the big wheel 60 so 80 spokes and nipples in total. I will order a special machine cutter to thread the holes in these nipples so I can cut the thread with one go on my lathe. Doing this by hand would take me forever and a day.
Problem is that my regular shop where I buy my tools is having problems with their supplier so there is a delivery backlog at the moment. I'm still waiting on a chamfer tool for stainless.

Cutting the tube for the rear wheel rim!

And voilá: I tried the contraption I made with the follower on the tube for the small (rear) wheel. It went great! Everything worked out like predicted and I could make a clean cut on the tube to separate the rim from the upper part.

Finished rear wheel rim (needs some deburring). I asked the mechanic - who rolled the tubes for me - to make sure the welding seam of the tubes would be on the outside so it would be cut off. As you can see, the seem is on the inside... :-(

Angle grinder follower tool

As promised: a few pictures of the follower that I made attached to my little angle grinder to follow the outer side of the wheel tubes whilst grinding.
I used the threaded holes on the side of the grinder to attach the follower. The long bolts I welded to the follower is to adjust the distance between the follower 'legs' and the center of the grinding disk. Since the bigwheel and smallwheel have different diameters (obviously), adjusting this distance is necessary.

Wheels...

The two tube wheels have finally found a way to my little workshop...!
I started making a kind of a 'follower' tool to attach to my angle grinder, so I can cut the tubes in half with confidence. Pictures of the follower to be posted later when finished.

The big wheel has a total diameter of 55", the small wheel 17"

Front wheel!

Hello and a happy new year to anyone out there reading this blog!

Yesterday, I visited the workshop where my front rim is made and guess what... it's done!
At least, it's the rolled tube, so the rim itself will have to be made at home in a device that cuts the tube in half.

I left the tube in the workshop, so the mechanic can use it as a jig to make the backbone. He also will make the rear wheel by the end of next week.

It's almost time to order the front and back tires and start with the front axle and fork assembly.