Front Axle Nuts

Being that I was trying to get the nuts to be as narrow to the lower legs as possible, for the minimalistic look, I needed the tapped hole to be flat bottomed. After machining of the top 'divot' and the fully threaded hole, I only have .065" of material between the two features. I peck drilled the 3/8" drill to just short of the .700" full thread depth I needed. I then used a 3/8", 4 flute, carbide end mill to open up the 37/64" dia c'bore that I need to run a 5/8-18 flat bottom tap in there. The nuts got threaded, chased again with the tap to ensure good threads, and then deburred waiting for the axle to be lathed.

Top view to show a better view of the 3-d machining that we did. They look sweet, like something off an F-1 car. Stainless sucks to machine and it\s really good at cutting your hands when trying to deal with the edge burrs and the chips, but it looks awesome machined with good carbide cutters. I know that many of your thinking, well that looks like a normal nut, why did you spend the time and money for material to make it, rather than buy it. Becuase you can't buy this nut anywhere. Most flange head nuts, are through threaded, not blind this design. Most nuts have a smaller aspect ratio of the ID thread, to hex size to OD than this. My design is the perfect fit for my bike, and that is all that I want in the end. I don't care if it takes a long time to design or make. I won't cut corners on my projects.
Axle Nuts in process. Started with that 1.625" dia 303L stainless stick. Programmed the 3-D milling with the help of Chad (BAKER Design Engineer) and Kris (BAKER Prototype Machinist) using Featurecam. Cut some slugs off of the stick, Kris milled some round pockets in the soft jaws of the small haas, and we knocked out the hex nuts to the state you see here. Note how the nut in the vise has a much smaller flange thickness on the bottom. I have already used a 2.5 dia indexable cutter to face it to the final .800" height. The other nut is next for a haircut.

Sprocket Spacer

Looks good because it all flows together like it was designed for this bike. When I do final assembly this will look even better yet. Some high grade fasteners, stainless safety wire, some real race car/bike stuff.

You can see the spacer snout sticking out here. Will look a lot better when I whack that off a little.

Sprocket spacer after a few hours at the mill. Lots of chips ended up on the floor, but it is hard when working with scrap, to get blanks that are fitted to the final part. I ended up having to space out the sprocket .390". After final fitment, (in the next couple of pics) I see that I need to face off about .050" from the end of the sprocket locating snout on the spacer. That's an easy 5 min task on the lathe.

Found some scrap in the shop that would suffice for machining out a sprocket spacer. Some aircraft grade 6061.

Another view, same spacer.

So here is what the left rear wheel spacer looks like in place. Kind of weird looking but I knew that I was going run a sprocket spacer to get my trans sprocket and wheel sprocket in line with each other while maintaining the rear wheel centered in the chassis. So I designed in the step to match up with the face of the sprocket.

Rear Brake In Place

So I have had this rear brake caliper on and off the bike, probably 15 times. My best guess is I will do that another 8-10 times. What you have to do if you want to get it right rather than 'close' or 'that's pretty good'. Caliper pictured in it's final resting spot. The bracket that gets welded to the frame will mount on the bolt closest to the frame tube in the bottom pic. Kind of a shame to hide all the work behind the frame, but it still looks sweet and unlike any other set up I have seen to date.

Rear Wheel Spacer Install

I test fit the wheels spacers, well at least the rear ones and they fit great. I still have to turn up my new front axle on the lathe before I can fit the front spacers. You can see in the last picture the mating line of the rear brake bracket to the wheel spacer. This is what I wanted it too look like, a smooth transition from the brake bracket to the wheel spacer to the wheel. Small .050" or so air gap left between the spacer and the brake rotor which is necessary. The bolts are hardware store mock up ones, they will be replaced later with stainless hex heads drilled for safety wire.

Rear Brake Assembly Models

Here are the models I created to ensure everything fit together as a unit. I felt it was necessary as I am using parts and pieces from multiple different companies that have never been put together how I intended to do it. It's funny how it all works though. My models like all scientific but when I opened the file it was all misaligned. So either my models were off or I measured the parts at home wrong. Oh well, that is part of the deal. I will check it out when I get home to verify everything.

Front Axle Assembly

Here is my front axle set up. Pretty straightforward except for the fact that I making every part. Most bikes built out there use a stock style front axle that slides in from the right side of the bike. and has an ugly flange nut on the left. I laid out the tire the tire and widths of the lower legs to give the right amount of crush on the front wheel spacers. Spacers are aluminum, axle 4140 steel. (think hard steel that won't bend) and the nuts will be stainless. Every nut, spacer or bracket really matters too me. It is easy to look at a bike and see that they used a certain part becuase it was on hand or easy to use, becuase doing it right was too hard, expensive or beyond their available resuorces.

Wheel Spacers

Here are the wheel spacers. At the most basic level wheels spacers can be tubing, cut to length. Well, I have always thought that looked unfinished. I don't want to see the seal and bearing in the wheel. I always noticed it right away, so I would think that other people do too. Small end of the spacers to the outside, big end of the 'bell' towards the wheel. There is a small diameter boss to the inside that lands on the inner race of the wheel bearings. The major diameter covers the seal and flows into the wheel. The really short one stacks up with the rear brake bracket to set the wheel spacing. These parts are my first venture into CNC lathe work. I wrote the program, set up the machine and ran them. Kris (BAKER Machinist) helped me throughout the entire deal.