In all, the project took approximately 5 hours and cost about 10 bucks (considering the belts were free, so the only cost was the pen kit and adhesives).
Leather (from belts, shoes, or anything, really.
Cyanoacrylate - NOTE: Cyanoacrylate (CA) is dangerous not just because it bonds skin, but it also reacts violently with cotton (ie bursts into flames). Do not let it touch your skin, clothes, paper towels, etc.
Pen kit (available at specialty woodturning/woodworking stores and catalogs - I used a 7mm twist mechanism kit)
Linseed oil - resin finishing mixture
Scalpel or razor
Power drill/drill press with appropriate size bit and pen mill/reamer
Mandrel and bushings of appropriate size
Woodturning tools (I used a 1/2 inch spindle gouge and a 1 inch rounded skew)
Sandpaper (150-220) and nylon sanding pads
Mallet and spare bushings (potentially)
Step 1: Preparing the Belt Leather
Use a scalpel to cut the ends off the belts to remove the buckle and the part of the belt with holes. These can be discarded. Cut the rest of the belt into six inch strips (photo 2). NOTE: I tried cutting the belt with a saw and a rotary cutting blade - they did not work nearly as well as my scalpel, so use a sharp blade.
A typical leather belt (such as these) is two strips of leather glued and sewn together. The belts I had were both black sewn over brown (photo 3). One belt is enough leather to make a pen, provided you use both sides of the belt. I wanted a black pen, so I needed two belts.
Separate the two halves by cutting off the seam and ripping the leather apart. It may be easier to cut the seam off one face and then off the other (photos 4-6). Do this for both belts.
Discard the brown pieces (if you want). The quarter is for scale (photo 7).
Congratulations, you now have enough leather strips for the pen! Make the pen blank after the jump.
Step 2: Make a Leather Pen Blank
I alternated strips from each belt from the outside in because they were slightly different shades of black (photo 2).
Spread contact cement on the different faces of the leather and stick them together. Follow the instructions on how to do this - some contact cements require a sitting period before contact (photo 3).
Put them in a vice overnight for the cement to cure (photo 4). I put masking tape on the vice so I didn't cement the leather to my vice.
The next day, I filled in all the gaps with CA. Leather apparently is really absorptive, which made this pretty equivalent to dousing the entire thing in CA, so watch your fingers (photo 5).
Congratulations, you now have a pen blank! Prepare it for turning after the jump.
Step 3: Prepare the Pen Blank
Drill the pen blanks with the appropriate drill bit (photo 2). My pen kit is a 7mm chrome pen (photo 3).
The pen kit I used has brass tubes. Sand the layer of oxidation off the tube with a nylon sanding pad (photos 4 and 5). This will allow the tube to better adhere to the blank. NOTE: don't sand down the circumference of the tube or it will be too small.
Cover a plastic straw with CA and feed it through one of the holes. Swivel it around to coat the inside with CA. Pull the straw out and slide one pen tube all the way in. Repeat with the other half (photo 6).
Use a saw to cut off as much excess leather on either side of the brass tubes. Use a pen mill/reamer to get all the way down to the tube (photo 7).
Congratulations, you now have a pen blank ready to turn. Load it on the lathe after the jump!
Step 4: Turn the Pen
Start turning the pen. I set the speed to around 2500 RPM. NOTE: Please wear goggles at the very least. I'd advise wearing a face shield and also a respirator - turning this produces a lot of particulate matter covered in contact cement and CA.
I used a spindle gouge at first to start bringing the blank to round (photos 2 and 3). Throughout the turning process, the leather strips will probably start to pull apart (photo 4). You'll be able to hear it flapping if this happens. CA the strip back on if necessary (photo 5). Work slowly and carefully to prevent this from happening (and sharpen your tools often).
Bring the blank to round (photo 6). After the blank is in round, switch from the spindle gouge to a skew. Use a plunge cut next to every bushing so each end is the same width as the bushings (photo 7). This will act as a guide for the width of the pen.
Using the skew, keep working the blank down. I recommend a toe-first cut if you can; I found the heel-first cut was more likely to pull the strips apart (photos 8-10).
When the pen is just slightly larger than the bushings and/or has the shape you desire, start sanding with 150 grit. Work your way up to 220, and then switch to nylon sanding pads up to your desired grit (photo 11).
Use a polishing rag to cover the piece with linseed oil - resin finishing mixture and wet sand with the nylon pads once more. This will fill in any gaps with an oil-resin-leather slurry to make the pen extra smooth (photos 12-16).
Congratulations, you have now turned your pen! Assemble it after the jump.
Step 5: Assemble the Pen
Follow the instructions included with the pen kit to assemble your pen. For my pen kit:
Jam fit the pen cap into one of the tubes using a vice (photo 3). Jam fit the twist mechanism into the other end of that tube (photo 4). NOTE: Test the twist mechanism repeatedly as you jam fit it in to make sure you don't over extend it. Jam it in until the tip twists out the amount you want (photo 5 - I prefer long pen tips).
Jam fit the cap and clip into the end of the other tube (photo 6).
Push the top tube onto the twist mechanism (photo 7). Depending on the leather, your pen may have a "grain." Align the grain in the open or closed position according to your preference - I prefer aligning it closed because the pen is covered by my hand when open.
Congratulations, your pen is now complete! (Photo 8 with a detail shot of the grain photo 9).