Intro: Mountain Bike Folding Saw Holder
Every winter in the New England sates we suffer the effects of a harsh winter with downed trees and branches. Every spring we are back on the trails to remove this blowdown and make the trails ridable again. A folding saw such as the Fiskar's Power Tooth 10" works great but does not come with a way to easily carry it on a mountain bike. The usual way to carry it is to zip it in the largest pocket on a hydration pack. It's a bit of a pain in the neck to take off the pack to access the saw every time you need it. This Instructable is my solution to quickly access my saw and at the same time hold it securely while bouncing down the trails that feel like you could jar you filings out
Step 1: The Saw Holder on Bike
My solution to this problem was to mold a piece of PVC pipe around the saw so that it would hold the saw, attach to the water bottle mounts on the bike frame and allow quick access.
Step 2: Materials and Tools
Materials to make the holder for the Fiskar Power tooth 10" saw listed below. Other saws may require modifications to the form and procedure but this Instructable should help you figure out what you need for your saw.
10" - 1.5 Schedule 40 PVC pipe(available at home centers)
1ea - Form for molding. In this case a piece of wood about 15" long, 1.665" wide and about .868" thick with the edges rounded with 1/2" radius router bit. The dimensions are measured off the piece that I used and they worked well but I think close enough would be good enough.
Oven to heat PVC to 325 degrees F.
Saw to cut PVC and wood. I used a table saw.
Router to radius form, could be done with hand tools such as hand plane or spoke shave.
Vise and scrap wood to form pipe around form.
Step 3: Prep 1.5" Pipe for Molding.
To fit the pipe over the form there needs to be a slot about 3/4" wide cut out of the pipe. This can be done with a hand saw or as I did with a table saw.
To do it with a table saw.
1. Cut a piece of plywood the same with as the pipe and at least 8" longer.
2. Glue the pipe to the plywood with hot melt glue. Use the fence of the table saw as a guide so they are parallel.
3. Lower the blade on the saw so that it only cuts the plywood and the pipe.
4. With the fence set so that the cut line is offset from the center SLOWLY cut a slot in the pipe. (Slowly because a fast feed will cause the pipe to fracture and shoot out shape fragments.) Then move the fence to the other side of center and make another cut. You can do this a couple of time and get the slot about 3/4" wide. You could measure and do this if your a perfectionist but this approach worked for me. What you want is to be able to push the form into the pipe but not have it slip out of the slot.
Step 4: Prep for Forming Pipe
Next ct some scraps of wood longer then the pipe that will fit in the vise and compress the wood around the form. I also had a couple of clamps the squeeze the ends of the wood so the pressure was even. You can notice there is a piece of wood at the bottom of the throat of the vise. This raises the assembly up so that the force of the jaws closing is centered on the form and not trying to pinch the top of the pipe rather applying equal pressure and making the sides parallel. Make sure this is not so wide that the jaws will not close completely on the form. Leave this set up and ready to go while you heat the pipe.
Step 5: Heating the Pipe.
1. Slide the pipe on the form and set it on a baking pan so that the pipe is slot down and not touching the pan. You want it slot down as the pipe will get soft and fall off the form when it gets hot. Turn the oven up to 325 F and wait about 15 minutes.
2. Have some gloves on and remove the pipe from the oven and quickly more it to the vise.
3. Turn it slot side up, set it between the boards in the vise.
4. Make sure the pipe is touching the board on the bottom of the vise and the form is on the bottom of the pipe.
5. Close the vise and pinch the pipe to the sides of the form use some clamps if necessary to make sure the pressure is equal along the length of the pipe. The pipe should close in on the top of the form, you want this to happen and use your gloved hand to push it down equally if needed, I only had to do this is one small spot.
6. Work quickly to do this as the pipe coos and gets ridged fairly quickly, you have time to make these steps but not much more. In about 10 minutes the pipe is rigid again and cool enough to handle.
Step 6: File and Sand to Shape.
I started with a 10" piece of pipe to give me some extra to play with. The finial length I trimmed it to was 7.5". I worked at filing and sanding the slot to it's finial width and trimming it to the right length by trial and error. In the first picture above the top of the slot is pinched in more than an 1/8". By the time I was done filing and sanding the top was only just pinched in a little bit. As you work with it you need to find a point where it will hold the saw firmly but still come out without a major issue.
Step 7: Finish
To finish, drill hole in the bottom to hold it to the bike water bottle bushings. The bushings are usually 2.5" apart and 7.8mm bolts. Check yours before drilling.
To paint first clean PVC with acetone to clean any wax off it. Then sand with 220 grit sand paper and paint with Krylon Fusion paint. It's made to paint plastic. Mount on bike and get out there and clean up those trails