Resurrecting an unwanted monstrosity as a 8 TPI rip saw

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A week ago I wrote about some used hand saws which caused me great disappointment. Following shared commiserations and encouragement from some of the master saw makers amongst us, I thought, why not.

Two of the smaller saws have very elegant skew-backs. These are the saws I’ve destined to be my users. So I chose one of the larger ones to practice on. Out came the angle grinder, and the games began.

I didn’t take any photos, but using Ian’s method of clamping some angle iron against the saw plate and running a cut-off disk along the top, I sheered off about 5 mm of plate. This was sufficient to remove both the teeth, and any of the “sharpening” that the previous owner had done.

The last time I cut teeth, I created a template from Tasmanian Oak, which splintered terribly, and had to be discarded after one saw’s worth of use. This time I grabbed some Spotted Gum (or so I thought). Using my ruler which was clamped to the vise at the same height as my template, I transferred 3 mm increments, which would give me roughly 8 tpi to my template piece of wood. What I like about this method is that you don’t need to rely on visual accuracy. You place your knife in the ruler etching, slide a square against the knife, then score against the square on the timber.

With the marking complete, I created a furrow using a chisel against each knife wall, into which the hacksaw rests to cut the template.

Then with some blue tape on my saw blade, I marked the depth of my teeth. This was a bad idea. The last time I did this, I set up a piece of wood as the stopper. So when the saw hit the wood, I knew I had my depth correct. Going by eye to a pencil line on blue tape was never going to work. If only I had figured it out at this point. I also WAY over estimated how deep the tooth gullets needed to be. One of the key differences with a hand saw compared to a back saw, is that they are long, with many more teeth. So my tough-as-nails template would need to be re-used several times along the length of my saw. It was then with dismay, that the spacers of my template kept breaking off. Later that evening whilst relating my tales of woe to my wife, she looked at the wood, and said “but that’s not Spotted Gum, I think it’s my left over Merbau from the bench seat I made”. Oh bother. So much for using a stronger wood as a template.

No problem though, I’ll just draw the remaining teeth spacing onto the masking tape. Whilst this worked (relative to being guided by the saw spirit), I was surprised how much harder it was to get the hacksaw to bite without slipping when there was no template to hold the blade in position. I may try the paper template and a file to make the initial markings on my next saw.

Once all the teeth were cut with the hacksaw, I moved onto shaping and sharpening. The last time I did this, it was during the day, in front of a great big window. This time it was evening and the sun had set, leaving me to rely on artificial light. What bliss, what joy. If we recall the law of reflection, that the angle of incidence equals the angle of reflection, I found that my filing position put my head in the reflection path from a ceiling light which made the unsharpened tooth flats gleam like an angel heralding a new dawn. It was so much easier to know when each tooth was sharp.

By the time I had the last tooth sharpened, the crick in my neck was firmly established, and enjoyed a well deserved stretch and head roll (as I repeated the action just now whilst writing it, a twinge remains on the back left).

So how did it turn out? Well, it’s sharp and does saw. It’s nice seeing small “chips” rather than dust ejecting from the cut. However there is no set yet, so will smile nicely at Adam and ask to borrow his saw set again. One thing I am pleased with, is that the saw stroke is smooth. No hang ups along its entire length. This is the second saw I’ve filed to a 4 º rake. I think the issue I had with my tenon saw, is that whilst aiming for a 0 º rake, you don’t need to vary much to induce a negative rake, which then catches terribly. I had read somewhere that Ian files his saws at 4 º, so thought I’d just emulate the master.

Some teeth do look like a modern art sculpture due to the too deeply cut gullets. Oh well, they’ll recede as it’s sharpened over time.

A final note. I know there is much discussion about saw files, so thought I’d plug my little wrong-size, broken-tipped Pferd file. This is its fifth sharpening, two of which required shaping new teeth from scratch, and it continues to work well for me. I have ordered some proper Bahco saw files that are making their way across the Bass Strait to me as I type this, so will be keen to give them a whirl when they arrive. This one now has sentimental value though, so don’t know that I could just throw it away when it’s done. It will have to be converted into something I can keep. Now what was a I reading just recently about making a birdcage awl?

Lance

September 2019

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