Bike repainting, graphically speaking

Posted on June 16, 2010

A barely maintained bike, ready to breathe a new life

Depending on how good you are with bicycles, you could repaint a bike with your hands tied behind your back, or you’ll find out that you are not all that familiar with bicycles after all.

I wasn’t familiar with bicycles after all. All these years riding and being seen as the “bike guy”, I realized that I couldn’t take a bike apart completely. It would take me days struggling with never-before-seen tools, the wits of some of the top bike mechanics in Guelph, and numerous trips to different bike shops before I could finish repainting my bike.

Rust taking over crucial areas of the bike

Riding through three wet, salty winter seasons took a toll on my 20-year-old, used bicycle. Rust was munching at the entire frame. If left untreated, I might find myself wedged between two halves of a cracked frame while riding. Something had to be done.

This looks like it could snap at any time

Initial Attempts at Disassembly

On the first day, I could only go as far as a set of Allen keys and wrenches could take me. I was stuck with the cranks still attached to the frame, having nary an idea how to remove them.

I brought the frame to Backpeddling, arguably the largest bike shop in Guelph (It’s where I bought the bike to begin with, actually). A team of mechanics were always working on bikes; I’ve never seen them idle. I asked one of them to point me the tools I needed to take the cranks off. He handed me a fancy bottom bracket wrench and a crank extractor, briefly taught me how to use them, and exchanged looks of uncertainty with me as I gave him a blank stare.

I paid for the tools. With excitement, I settled outside their shop and started to work on them. It wasn’t going anywhere. I went home and continued to work on it. Despite my best efforts, I could only get one crank off.

Seeking Professional Help

I looked for answers online. I watched hours of videos to make sure that I was turning the wrench in the correct direction. While hunting for help, I landed on Winterborne Bikes, a specialized bicycle shop which also offers accredited bicycle mechanic courses. Considering all the struggles I’ve endured in the past few days and with encouragement from a fellow bicycle friend, I called them and booked a crash course for the laymen with them  – The Park Tool School.

I went to their offices a few days later to pay for the course. I mentioned my battle with the crankset. Jay offered to help me figure it out but couldn’t remove the crank either. He offered to solve the problem the next day, using the frame as a teaching aid in his class – a special course on how to remove “stuck on stuck” bolts. “It’ll be done by noon; you can pick it up then.” I told him they could do whatever they wanted with what remained of the bike – I just wanted the frame.

Sure enough, I found the frame completely stripped off its components when I got there at 2pm. “We had to cut through the bottom bracket. You were OK with that right?” “Sure.”

Sandblasting

I’ve repainted bike frames twice before. The first time, I lightly sanded the frame and painted over an existing layer of paint. The frame was in good shape but the bike was stolen before I find out how durable this method of repainting was.

The second time, I attached a set of wire brushes to a power drill and worked a week off to remove every flake of paint from the frame. The result was a nice, brush metal effect that eventually worked its way to become the bike frame coffee table. It was laborious. It was a method I wanted to avoid for this project.

The easiest option was to sandblast the frame. It would be quick, clean, and probably cheaper. I found only two sandblasters in Guelph. I called the first.

Me: Hi, do you guys do sandblasting on a bicycle frame?
Them: Bicycle frame? Sure
Me: How much is it going to be?
Them: It's $100/hour
Me: Uh, ok, how long is it going to take?
Them: It depends on the material used and the size of the bicycle
Me: Have you guys sandblasted bicycle frames before?
Them: In the past? Sure, one or two, a while ago
Me: And you don't remember how long those took?
Them: No
Me: Can I drop by, let you look at the bike and have you quote me a price?
Them: Well, it's going to depend on the material used and the size of the bicycle
Me: Uh, ok, thanks, bye.

I called the second.

Me: Hi, do you guys sandblast bicycles?
Them: Bikes? Uhhh... yeah, we can sandblast bicycles.
Me: Great. Do you know how much is it going to be?
Them: Uhhh.... How big is the bike?
Me: Well, it's a road bike. I'll disassemble it and let you guys paint it – sorry, sandblast it to remove the paint.
Them: It's hard to say. But it could be... and this is just a ballpark figure... between $25 and $50.
Me: Oh great! Can I come by tomorrow?
Them: Yep, sure, if I'm not in tomorrow, my father will be here. His name is... [forgot name]
Me: Ok, great. Thank you very much. Bye bye.
Them: Bye.

I took it there one morning, and got it back sandblasted in the afternoon. They charged me only $25. Cheap and easy, wasn’t it?

Not so fast.

Extremely abrasive surface that could do no good

The sandblasted surface on the frame was extremely coarse. It’s great to look at – all shiny and white – but the sandblast had taken a big chunk of metal all over visibly. I was concerned. If the threads for the bottom bracket and bolts for racks were sanded away too much, they may not be strong enough to handle stresses they were designed for.

With reservation, I proceeded to paint the frame

Two main parts of a bicycle – the frame and the fork – hung and ready for painting

A layer of primer wasn’t necessary, but to make sure that this job will reward me for years to come, I decided to use it. I hung the bike frame in the garage, lined two desktop fans along the bottom of a slightly opened garage door to keep the work area ventilated, and went straight to work.

A complete disassembly of the bike gave me an opportunity to clean the components thoroughly

As I added more layers, it became obvious that the surface of the frame was too coarse. No amount of paint was going to smooth out the surface to its former, glossy glory. I’ve realized too that not all masking tapes were created equal; one particularly cheap kind allowed wet paint to seep under, defeating much of the purpose of using masking tapes.

With the help of a piece of masking tape, I hoped to create a neat seam between the chrome paint and the black paint on the frame. Unfortunately, paint leaked under the masking tape

I tried to fix the problem by painting over with chrome paint, but it wasn’t going anywhere. I wasn’t ready to spend the next couple of days perfecting the boundary between black and chrome, and left things where they were.

After learning how to disassemble a bicycle, reassembling was straightforward. In the end, I was extremely pleased with how smooth a “new” bike feels. I was surprised to find that the coarse sandblast job had given the paint a Teflon feel, which could keep the frame cleaner, longer. Time will tell.

Lessons learned

With the frame newly repainted, the bike looks sexy once again

And here's the bike in full view.