Getting the frame and some small parts cleaned up and back to bare metal has been a process of trial and error.
Obviously, sending the frame away for sandblasting and powder coating would be the easiest/best/least painful method of preparing the frame for the rebuild. I am trying to do as much of the project ourselves, rather than sending away. The $$ is definitely a factor, but mostly we are just chasing the satisfaction of doing as much as possible.
I firstly tried a wire brush attachment on the angle grinder. Then a sanding disc on the grinder… Both were ok, but I really struggled to get into the welds and difficult angles. It was also super slow going and I didn’t have much time to spend to spend on the project. At this rate it would take me 10years to get the bike ready to put back together!!!
After the frame sat for a month or so without any work being done, Wayne suggested we soak it in molasses. He filled a 44-gallon drum with molasses he bought from the local produce and feed store; it’s bought as a liquid concentrate which you water down depending on the application. The frame was too big for the drum, so it needed to be done in two stages. I dangled some small parts from wire in the drum as well, triple stem plate, engine mounts etc…. Cover the brew up with a tonneau cover and we wait.
I am not sure about how long it should take, or what the minimum time would be…so maybe this process could be faster next time. We waited nearly 6 weeks before uncovering the horrible smelling drum and rescuing the frame. The photos below are following a light spray from the garden hose. The bulk of the paint and rust just washed off without any effort.
With the remaining paint, I experimented with using a wire brush, a high pressure hose system, scraper blades…but nothing would budge what was left. The molasses had stripped almost 80% of the frame back to shiny bare metal. Encouraged by the results we returned the frame for more soaking. Honestly, I don’t think the second soak was worth the extra time, with very little of the remaining paint coming off the second time. I was getting impatient by this time, and we finished the frame prep with chemical paint stripper for the bulk of the work, and a little bit of sanding with a Dremel for the final touches.
The verdict for next time… If I still didn’t want to send for sandblasting, I would soak for 4 weeks in molasses, hose it off, and then finish with the chemical stripper. I absolutely hate using the chemical stripper, so in my mind, minimising the amount needed by soaking in the molasses treatment first is worth every day of waiting. It is also ridiculously cheap!
This is not an option if you care about your neighbours (molasses stinks as it ferments in the barrel), lack the space to have a drum laying about for a month, or if you are in a hurry to strip down and get started on spraying.
This might also be the inspiration for the bike’s name when we finish…Sweet molasses? Brown sugar??