Build a Bike Trunk

by Scott Elkington

4.7K585

Intro: Build a Bike Trunk

I was using an old backpack strapped to my bike rack, to carry water, a lock and a few tools for my bike. I decided I wanted something a little nicer. A bike trunk I thought. So I scoured my shop for things to use. Here's what I came up with. Tools I used:

1.My trusty home built-from-kit CNC router. and router bits

2. Table saw.

3. hand electric drill and drill bits

4. hand roller (like an ink roller)

5. measuring tape

6. Chop saw

7 Sander and sandpaper.

STEP 1: Make the Top

The pipe size is going to control the dimensions of your base box and there is almost no limit on what size pipe you can use. for me I chose 6 inch pipe that has an OD (outside diameter) of 6.25 inches. To split that in half I set my table saw to 3.125" to the center of the blade. After I cut mine on the table saw, I squared the ends on my chop saw.

I cleaned the pipe with isopropyl alcohol then roughed up the outside with 200 grit sandpaper. Then I cut my veneer to approximate size (go big) and then applied contact cement to the mating surfaces both pipe and veneer, as per the manufacturers instructions on the can. Once the cement was tacky to the touch (follow the instructions on the can) I carefully laid the veneer on top of the pipe and wet it with a spray bottle of water. Be very careful as there are no re-do's with contact cement.Then I rolled it out, see the video. Then I carefully measured and and created the top end caps on my CNC. I think this part could be done with a router and a jig. Then I trimmed the veneer flush with the 1/2 pipe edges.

Lastly I glued the end caps, that are simply a 1/2 circle of hardwood with a 5/16 in groove 1/4 inch in depth and 3/16 in from the outside edge. on with epoxy. carefully line up the caps And then sanded the bottom smooth.

STEP 2: Make the Box

There are may ways to make a wood box the will accept the lid described above, I made my box the same length as the top but kept it 1/4" wider to accommodate plastic shims curved on one side to fit the top and flat on the other to fit the hinge . As for box style, you could choose, everything from simple butt joints, box joints and dove-tails etc. I chose to make mine the hard way with my CNC machine and a 91 degree miter fold bit. The 91 degrees assures that you have enough room in the joint for glue. this is important for epoxy as it gets its strength from a relatively wide glue joints unlike resorcinol and white glues that get strength from a thin glue line. You can see in the video how I cut the box parts on the CNC and had a bit of a struggle to get it clamped together, as the joints kept wanting to ride up on each other. I've experienced this same problem trying to nail a blob of Jello to the wall.

STEP 3: Assemble and Finish

1.Before I attached the lid to the box I spent a few days doing 4 coats of real varnish.

2. I did a french polish and finished with a coat of wax.

3. I fitted the hinges with the plastic shims made on the belt sander with little pieces of PVC pipe.

4. I added the butterfly latch to the front. You can padlock this latch.

5. I fitted the inside of the box with some scrap foam and made 2 levels of cut outs for my bike tools

6. I used a heat gun to bend some pieces of PVC pipe to hold my water bottle in the lid and glued those to the lid with PVC cement.

In conclusion here is a short 2 minute video that will fill in some gaps for you. Hop you enjoy watching as much as I enjoyed making the trunk and the video.