Progress over the last week or so....

steering stem the black stripe is CF over thickened epoxy

Things continue to evolve, although I continue to hit "engineering challenges" at every corner. So far so good and I keep finding solutions that seem to work. I have the stem put together, if you recall from a few posts ago, it was cut in half so I could reattach it with a 90 degree turn in order to facilitate my steering mast. It is ugly, but it seems pretty strong. It is wrapped with fibreglass, then thickened epoxy followed by some CF ribbons wrapped around. I wrapped the entire package with the electrical tape to hold it nice and tight while it cured. So far so good, but I think some paint may be required or perhaps some finely wrapped CF ribbon to make it look a bit better. I have told myself all along that I'm not trying to build a beautiful bike, just one that is strong and that works. It is still some times frustrating to look at something that is really rough looking after looking at some of the beautiful sleek CF bikes that have been made. I guess you have to start somewhere! I will be happy if it goes off-road and does what I want.

I have put the bike into as complete a state as possible and had a "sit" on it to get a feel. I am very happy so far. Just to get an understanding of the size, the wheelbase is right around 6' so small she isn't. I have the necessary parts now to build my custom roof rack as soon as the bike is done.

The front end with the hole drilled for the bottom bracket

This week I drilled the hole for the bottom bracket and put a bit of CF inside to ensure I have a strong base to bond the BB to when I put it in. I made an attempt to put the BB in today but ran into problems trying to square it off in all three planes. This is my toughest engineering challenge so far and have decided that I need to wait until the seat is on so I can have a good location to measure distances from. Since nothing on the bike is square, it is really difficult to make one component perfectly square. Now I understand why diamond frame builders put the main components in a jig and then build the frame around them......maybe next time?

I have continued with work on the swing arm. This week I added some thickened epoxy to strengthen the joint between the arms and the shock mount. Today, I installed some aluminum angle pieces on the underside which will be the lower connection piece for the shock. I attempted to make some CF angles using the aluminum as a mold, but they just didn't seem strong enough and I didn't want to take more days building them up. The swing arm is looking pretty ugly and has managed to get a slight warp in it from the last session in the vacuum bag. I thought it was strong enough to resist the bag from causing a warp, but my estimate was wrong. This swing arm will do for now, but I think it is definitely V1.0 which will be near the top of the list of parts to rebuild.

Swing arm with aluminum shock mounts bonded

The frame hanging and wrapped with electician tape

Today I added the next layer of CF to the frame. I have been having a problem with this process getting annoying wrinkles in the vacuum bag. Since I only have this plus one more layer to go, I want to ensure things are starting to look at least partially smooth so the bike doesn't look like I used a stipple brush to apply the epoxy. I decided to use the electrical tape wrapped backwards technique that has been used by other homebuilders instead of the vacuum bag. I also applied the epoxy with the frame hanging instead of on the workbench. The hanging worked much better and the panic at the end was only moderate this time. The last few minutes of epoxy application have gone from chaos the first time, through to moderate panic this last time. I consider that a good learning curve!!