Reply To: Saw jointing and teeth reshaping.. i’m frustradted
I’d like to point out a question I asked Paul on that blog post:
When dealing with tall teeth, would you estimate that you remove the flat equally from the top and front of the tooth? This post was an Aha! moment for me. Thank you! I’ve been jointing too heavily when fixing saws! I see now that, rather than going right for a nice flat profile and then dealing with sorting out how much to file each tooth, it may be much easier to take a moderate jointing pass, leaving some or even many teeth untouched, sort out the teeth that were hit, then repeat. This will naturally cause some teeth to be filed more as you repeat. That’ seems so much better than what I’ve been doing, which is to joint heavily and have various sized flats so that one must guess how much extra to give the wider ones vs. the medium and smaller flats. You remove a staggering amount of material in a single 2 1/2″ stroke based upon those two photos! That would have been half a dozen strokes for me. Maybe I need more hand pressure!
Paul’s answer was:
It is a question of gently, stealthily approaching the enemy in the land of the giants.They don’t mean to stand out. File off the tops of the highest ones and take down the big giants first; less to be overwhelmed by. File the tooth from both sides but remember too that you may want some to take off the adjacent tooth with a final stroke or two.
Saw sharpening is the hardest sharpening activity for me. I’m still unhappy with my ability, but my saw is usable. I’ve used saws sharpened by Paul and, while mine are okay, they aren’t like his. With that caveat, here’s my suggestion: Don’t try to get to a perfect saw like Paul does. Ideally, we want sharp teeth, equally spaced, equally shaped. My suggestion is to focus on sharp teeth, even if they are not equally spaced and sized. Let some be imperfect. Over time, as you sharpen more, aim for getting more as you want it. In the interim, the saw will be useable, even if not as good as Paul’s. So, get what you have sharp (meaning no flats, but maybe teeth vary) and properly set for your work. Make a test cut and ensure that it cuts straight. Even if the teeth are somewhat wonky, let it be and get to work. Resharpen often. You will gain confidence from this. For me, the key thing is that many of the teeth are sharp and level, even if not all, that I have the right amount of aggressiveness for the teeth, that the set is as small as I dare for the work and that I get a clean cut, not a jagged one. Trust me, you can achieve that even with imperfectly spaced teeth.
You don’t need a perfect saw to get a good or even perfect cut. An imperfect saw can give an excellent cut, but just be a little inefficient. For me, there is a threshold effect. I must get to the point of the saw not skating on my layout line (a matter of jointing and having enough jointed teeth sharp plus a little bit of being aggressive enough shape), and it should cut straight. That one is almost a must, but I’ve faked it in a pinch. Once you can get those, cutting without making a jagged kerf becomes important and, as your skill builds, becomes a must. I’ve achieved all of those on a saw that had imperfect teeth sizes and wasn’t perfectly efficient. If this paragraph is confusing, imagine a tenon saw that is convex or, worse, wavy in tooth height. It will want to skate. By contrast, if I joint it so that it is mostly flat but random teeth are low, I can get into the work without skating, but the random teeth won’t help cut, so the efficiency is a little less. This can be made good enough to get to work.
Please, please tell me you are practicing with a rip, not a crosscut. 🙂
I have seen so many cows and calves in the wild, and have seen them so uniform, that I honestly wonder if it was done deliberately for reasons that we collectively no longer remember.
I better say what I mean by, “skate.” When I cut, I somewhat unweight the saw and gently rub at the far side of my layout line until I’ve gotten a couple teeth exactly where I want them next to the line _and_ I’ve established my arm motion. At this point, I drop the heel of the saw. Especially on wider cuts, when I drop the heel of he saw to make contact with the layout line (especially longer ones), I want the saw to immediately enter the wood along its length. I don’t want it to take two or three passes dropping the heel more as I go or waiting for the saw to enter the line and I don’t want dropping the heel to cause the nose to jump and chatter out of the cut. Failing in this way is what I mean by skating. Saws that are reasonably called sharp (at the tooth level) can do this (bad) thing. For me, this is the Holy Grail of sharpening. One of Paul’s class saws did this better than any of his others and he sharpened all of them, so it is a bit elusive. I coveted that saw.
I’m restoring a small Bahco gent saw with 13 tpi. it had an hybrid cut teeth taht performed equally bad ripcut and crosscut wise. I reshaped all the teeth in rip configuration and added 12° rake. Nothing more than this.
A saw taht starts as you described makes easier to perform a plumb and straight cut . a pleasure to use. I got your meaning: we have good cutting saws withouth too much effort on perfection !