I thought I'd take a little time to relate how I repaired some BMW touring cases (old versions that use the flat latches w/ small luggage keys, as opposed to newer versions that use the tubular locks that take ignition keys). I have Krausers (and a set of BMW Krauser copies), but the touring cases are a little bigger and have much better latches. Obviously this procedure isn’t 100% optimal: please share tips, changes, and commentary! The more brains on it, the better. I took me a few hours, but I was figuring it out as I went. Hopefully it’d be faster with this procedure.
I was able to get a set of touring cases on Ebay for ~$150 shipped, and I already had the necessary racks. However, these (like many of the touring cases) had cracks radiating away from the rivets that hold on the latches—four between the two bags. At least on my cases the lids are ABS but the rest of the luggage (the piece of plastic that mounts to the rack) is something else--polyethylene? Not sure why BMW decided to mix plastics like that. One can test for ABS or not in this situation by wiping some acetone along an inside surface: if it dissolves the plastic (if you see black on the towel), then it's ABS (as my lid is). If it doesn't, it's not ABS.
ABS has the advantage of being easily solvent weld-able, and so it’s easy to repair. I’ve read about a few other methods of repairing these bags (fiberglass + epoxy, just epoxy, plastic welding), but this seemed the best to me (and I got to learn about working with ABS). One can have trouble getting epoxy to stick to plastics like ABS, though there are ways around it (e.g. rough up surface, clean with alcohol, then oxidize with a torch before gluing).
Anyway, I wanted to relate how I repaired the cracks and reinforced the cases so this hopefully won’t happen again.
You’ll require these things: 1) BMW, Krauser, etc. cases with ABS components needing repair or reinforcement, 2) Sheet ABS as here
, 3) ABS cement (most any hardware store), 4) Aluminum tape or other tape, 5) heat gun or torch, 6) a variety of shaping tools (hacksaw, drill, files, block plane, etc.)
There are six main steps: 1) stop-drill the cracks, 2) Tape the cracks with aluminum HVAC tape on the outside of the case 3) prepare some gap-filling ABS cement from regular ABS cement 4) prepare your reinforcing patch, 5) fill cracks, 6) cement patches in place 7) clean up.
Procedure in next post due to character limit.