Fixie Project - Part III

Part III (the sequel to the sequel) in this riveting series of blog posts about my fixie conversion project (you can go back and read Part I and Part II if you like doing things in order, or you can read them later if you're more of a Memento kind of person).

Ugly Bits - Out!

Next step in the conversion was to attack the frame with a range of low-tech weaponry to get rid of all the ugly bits that you don't need on a fixie.

In the picture above, you can see the bosses for the rear cantilever brake (the two little grey posts). You can also see the angle grinder I used to cut them off. Angle grinders are not only dangerous, but also great fun. Their strength is also their weakness - they can remove a lot of material (especially thin or soft material) very quickly. So if you go this way yourself, be very conservative with your first few cuts; you can easily grind more off, but putting it back is a lot harder. I've done a lot of angle grinding over the years and (patronising rant continues...).

Now the right-hand (driver's side) post has been completely removed. I didn't go all the way down to the tube with the grinder. I stopped a mm or so short and used a flat bastard file (a fair dinkum technical term) to remove the rest. Next (after the photo) I used a fine file to take out the marks left by the bastard file. Lastly I went over the general area with garnet paper (coarse wet and dry would be OK too). That one week basic fitting course I did during my industrial training was sure coming in handy.





In the photo at right, both bosses have been ground and filed off, as has the cable stop for the rear brake (the upper pair of shiny patches).

All that's left on the seatstays is the brake bridge with the mounting boss in the middle. I'll leave this in place, as unlike the cable stop, it contributes stiffness and strength to the frame.

Paint

Although I'm trying to build this fixie on the cheap, I still want it to look half-decent. My plan is:

1. Strip the original paint using that goopy citrus paint stripper.
2. Spray a couple of coats of grey primer from a rattle can.
3. Sand with #600 wet and dry to smooth down the primer.
4. Spray with the final colour (still a secret, but it's not black) also using a rattle can.
5. Apply stickers (I've bought the main ones for the down tube from Cyclomondo, and am still trying to decide whether to put on some others or remain minimalist).
6. Spray on a clear coat from a rattle can.

Like most plans, it didn't survive first contact with the enemy. The you-beaut citrus stripper was laughed off by the doughty Nottinghamshire paint. The paint stripped off the fork OK, but that was a fork I'd painted myself a few years ago. The frame wasn't having any of it. So I reasoned that if the original frame paint was that intent on staying put, I'd leave it in place as a base coat. Instead of trying to remove it, I'd just key it up with some very rough sandpaper. Where there were any chips or scratches, I'd sand them out, trying to remove as little paint as possible in the process.

So then I sprayed the whole frame with a very rough coat of primer, for two reasons:

• to stop the bare metal rusting while other things like job and family got in the way of a perfectly good project, and
  
• to act as a guide coat so that I could more easily find any scratches or chips that I had yet to sand out

The result was very encouraging; despite the new "westie grey" colour scheme, having the frame in a single uniform colour made it look a lot more attractive. Motivation is important in ad-hoc projects like this, where obstacles are always cropping up.

New Bits

Although I was able to reuse several bits off the old bikes, such as frame, fork, headset, stem, wheels, seat, and bars, I was going to have to get some new stuff as well, either because the old stuff simply wouldn't work (e.g. wrong gear ratio) or because it was too rusted to look presentable (e.g. the seatpost and its clamp bolt).

At the end of the project I'll post a full list of what I had to buy, where I got it from, and what it cost me, but the first things I wanted to fit were the drivetrain components:

• bottom bracket
• cranks
• chainring
• rear sprocket
• chain

These parts were a priority because they would allow me to check and adjust the chainline of my new ride. The new Shimano BB was initially hard to fit, and I had all sorts of theories about my frame having been made in Timbuktu and thereby having a BB thread unseen anywhere else in the world. It couldn't possibly have been that I had it around the wrong way, could it now. Either way, it fits nicely now.

Next were the new 165mm crank and 42T chainring, which went on without a hitch. My new 16T sprocket hadn't arrived yet, so I screwed on a BB lockring where the sprocket would go, just to give me a rough idea of the chainline. It soon became obvious I would have to do two things to get it anywhere near straight:

• Mount the chainring on the inside of the crank (with the new short chainring bolts I had bought), and
  
• Respace the rear hub to the right. Sometimes things just work out nicely; on the right was a 15mm spacer, while the left was a 5mm one. Swapping them around would move the hub 10mm to the right.
  

That was all good until the real sprocket (a Shimano 7600) turned up and had a big flange on it; so big that the locking I was going to use won't also fit onto the hub (see pic).

I'm still undecided what to do about this ... find out in a future blog post (or a past one if you're Guy Pearce).