Step 11: Finish Lugs

Step 10: Install Brake Bridge


2 Steps, ~3+ hours (the more time you invest in filing and sanding your Lugs, the better your bike will be)

Goal: Smooth your Lugs and clean up the transitions from carbon to bamboo. This step completes the building of your frame.

Materials: • Safety Goggles • Mask • Safety Sleeves • File • Sandpaper • Gloves • Epoxy Resin • Epoxy Hardener • Mini Pump • Plastic Container • Mixing Stick • Razor • Scissors • Damp Paper Towel • 2 Adjustable Wrenches • Tung Oil


11.1 Finish Lugs | Remove Bike From Jig

• Remove Bottom Bracket Bungs at the end of this step.


11.2 Finish Lugs | Finish

• Put on your dust mask, safety goggles and gloves. This step creates a lot of fine dust that you don’t want to get in your eyes or breathe in. Some people get itchy from contact with the carbon dust, so safety sleeves are recommended.
• Using the coarse edge of the file, smooth the Head Lug.
• Remove all bumps, bulges, and divots. This is both aesthetic and structural. You are trying to remove all stress concentrators.
• Take care not to remove too much carbon.
• Move around your bike to make sure the Head Lug is smooth from all angles.

• Repeat this step with all Lugs. You should be prepared to invest a significant amount of time in filing and sanding your Lugs.

• Once your Lugs are smooth and grey, wipe them down with a damp paper towel. Wait till the Lugs are completely dry before you apply your finish coat of epoxy.

• This step uses epoxy resin. Put on your gloves, sleeves, apron and mask. If you have a fan, turn it on. If you have a window open it. Make sure the temperature in your space stays above 70 F (21 C).
• Push two pumps of clear epoxy and two pumps of red hardener into a plastic cup.
• Mix until uniform color – about 30 seconds of sustained mixing. No streaks!
• When applying the final finish coat of epoxy to your Lugs, use a very small amount. You are trying to seal the lug with a thin finish coat.

• After the finish coat on the Lugs dries, use the razor to chip off any epoxy from the bamboo – be careful not to scratch the bamboo!
• You can also use the razor to score the transition between the bamboo and carbon Lug, to give it a clean edge.

• Dip the paper towel in Tung Oil, and rub into your bamboo. We recommend applying Tung Oil to the bamboo every few months to keep your bike weather resistant, and to make it shine.

Happy riding!


Bike Making FAQ
Step 10: Install Brake Bridge