I recently purchased a hand saw blade at a thrift store for next to nothing, simply because no one wanted it. It was missing a handle, rusty and in unusable condition. With a little effort I was able to remove the rust and make a new handle for it out of a discarded piece of plywood.
This tutorial will show how easy it is to repair and restore discarded tools that in turn will provide years of use.
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Step 1: Making a New Handle for the Saw
I think one reason no one wanted this saw blade was because it was likely going to be difficult, if not impossible, to find a replacement handle that would fit. That was my first thought when I saw the rusty blade.
I decided to buy the saw blade and make a handle that would fit. As seen in Photo 1, I started by using the handle from a pruning saw, that was roughly the same size as the newly-purchased blade, to create a pattern.
I traced the outline of the handle onto a piece of chipboard (thin cardboard used, for example, in making cereal boxes).
I then laid the end of the saw blade on top of the pattern to customize it to the saw's dimensions, as seen in Photos 2 and 3.
I found a discarded piece of plywood that I could use to make the handle. The plywood was not thick enough to make a strong, comfortable handle so I determined I would need to cut out two pieces from the plywood and then glue them together.
As I cut the pieces out I realized that the plywood was made from redwood and was probably manufactured for use as house siding. This was an added bonus to have a salvaged redwood handle!
I used a wood rasp to smooth out ridges that had formed on the plywood as it had weathered (Photo 4).
Step 2: Removing Rust From the Blade
I removed the rust by first using a wire brush to remove what little rust that I could, then soaked the rusted blade in a citric acid bath as seen in Photo 2.
Citric acid is used in beverages and in canning of foods (to preserve color) and may be purchased in powder form in grocery stores or online. It is a simple and safe method for removing rust.
I used 1 tablespoon (15 ml) of powdered citric acid for every 16 fluid ounces (.5 L) of water. I mixed enough of the citric acid bath to cover the rusted saw blade and let it soak. After about 30 minutes I took the blade out of the bath and scrubbed both sides with a wire brush. I continued soaking and scrubbing until the saw blade was free of rust, as seen in Photo 3! It took about 3 hours of soaking to remove the rust.
Step 3: Fitting the Blade to the Handle
To configure the handle, to accept the saw blade, I took one half of the handle and laid the end of the saw blade on top of the plywood to trace the location of the attachment hole and slot, as seen in Photo 1.
Then I placed both halves of the handle together and drilled a hole through both pieces, as seen in Photo 2, where the fastening screw would be located.
I carved out part of the handle to accept the saw blade and tested the fit (Photo 3).
As seen in Photo 4, I assembled the saw blade between the two handle pieces and marked the width of the blade on both handle pieces.
I then disassembled everything and marked the location of the pin that will fit into the slot. I made location marks on both pieces of the handle. I took a hardened steel rod having the same diameter as the width of the slot and cut it to length so that it will fit into both halves of the handle without protruding from either side, as seen in Photo 5.
I drilled holes in both handle pieces deep enough to accommodate the length of the pin and test fitted, as seen in Photos 6, 7 & 8.
Step 4: Gluing the Handle Together
Before gluing the two plywood pieces together I covered the area where the saw blade would attach with a thin coat of silicone sealer (Photo 1) to provide a little more grip for the handle to hold the saw blade in place, once the fastening bolt was tightened.
As seen in Photo 2, I used a furniture bolt that has a flat head on either side. One end screws into the other so that the entire bolt is hidden away inside the handle. Allen wrenches are used, one either side to tighten the bolt.
I made one last test fit (Photo 3) before applying wood glue to the entire area, minus the parts with silicone sealer. I inserted the pin into the holes and clamped both halves together.
Step 5: While the Glue Dries....
While the saw handle was clamped for gluing, I threw in another rusty circular saw blade (Photo 1), that I had purchased, into the citric acid bath. People discard rusted items because they don't want to deal with rust removal. Others don't buy rusted items for the same reason.
This is too bad because the rusted items are fully functional and the rust, as seen here, is easily and inexpensively removed using citric acid. Photo 2 shows how much rust was removed after 30 minutes and a good scrub with the wire brush. Additional soaking and scrubbing will remove even more of the rust. Photo 2 also shows that the citric acid will also remove the labeling on the saw. Another added benefit in using citric acid to remove rust is that the citric acid bath is nontoxic and can be poured down the drain or used to water ornamental plants outside.
Step 6: Finishing the Handle
When the glued pieces had dried I traced the center hole onto the handle and drilled two holes on either end as seen in Photo 1. The holes allow one to insert the blade of a coping saw or jigsaw to cut out the hole, as seen in Photo 2.
I then trimmed the outside edges of the handle as needed so the edge was uniform. I used a wood rasp to round the edges of the handle so that the handle fit comfortably in my hand. I sanded the entire handle (Photo 2) and applied 2 coats of polyurethane varnish to protect the handle. The polyurethane actually darkened the redwood to a very pleasing color.
Step 7: Project Completed!
All that was left to do to complete this project was to attach the saw blade to the handle and tighten the bolt!
The hand saw works wonderfully with the new plywood handle and the blade just gleams with the rust removed!
Hopefully this presentation on how to take items destined for the landfill and give them new life will inspire others to see the potential in unwanted items and find ways to repair and restore instead of discarding things and purchasing replacements.