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View Full Version : 10 degrees rake, 10 degrees fleam



lowell holmes
04-05-2014, 9:52 AM
Matt Cianci, in his excellent video "Supertune Your Backsaw" uses 10 degrees rake and 10 degrees fleam. He states that this makes the saw good for crosscutting and ripping.

We know that you can crosscut with LN dovetail saws and carcass saws. These saw are sharpened rip pattern.

What do you have to say about this?

Irregardless, I will set up one of my saws like he recommends.

Steve Voigt
04-05-2014, 10:02 AM
I read about this on Matt's blog a couple years ago and started sharpening my backsaws this way. It works very well. If I had more saws, I would probably have at least one in a more relaxed filing, for smoother crosscuts, but since I only have two backsaws, this works for me.
Bad Axe offers a "hybrid" filing that is pretty much the same thing; I think he uses 10° rake and 12.5° fleam (have to double check that). I was thinking about trying that next time I sharpen.

Ron Bontz
04-05-2014, 10:22 AM
I have tried the filing on everything from sash saws to half backs. It's an ok filing for sash saws, but not ideal. This is really the key. If you only have one saw to use. A starting point. The 10, 10, 10 is certainly in that vague arena of "Hybrid" filing. But you will always sacrifice one or the other to some extent. So how many saws do you have? Try increasing the pitch to say....12ppi with only 3 to 5* fleam. and compare it to that 10, 10, 10. Make sure you have your stop watch handy. :D It is really just going to come down to preference. I have since refiled my saws.

Chris Griggs
04-05-2014, 10:32 AM
That's the exact filing of my 12ppi sash saw...10 10 10. It's the best hybrid filing I've found and it does indeed rip and xcut very well, but as Ron says you do give up some ability of each. It's great for most xcutting and most small to medium size tenons but for very precise xcut work and large tenons you do begin to notice what you've sacrificed. Still very serviceable but on largest tenons the slowed down ripping becomes more noticeable.

All in all though, while not ideal for everything, it does make for a very handy saw for a lot of things and it's a filling I recommend trying.

David Weaver
04-05-2014, 11:03 AM
I'd agree with the camp of if you have the saws to file them specifically, it makes more sense to do it. A half of one and half of another type of filing is something to do only if you have to.

Adam Cruea
04-05-2014, 5:25 PM
It's a nice filing for a dovetail saw so that you don't need two saws to do all your ripping and crosscutting.

If I'm not cutting a dovetail, though, I go with a dedicated ripper or x-cutter. It's just faster and seems a little cleaner to me.

Jim Koepke
04-06-2014, 3:47 PM
Being able to experiment with different filings is the beauty of learning to sharpen one's own saws.

Saws can be filed to cut more aggressively, read faster. Or a saw can be filed to cut more smoothly, read slower.

Faster more aggressive saws tend to have less rake, less teeth and less fleam.

Fleam is mostly used on crosscut saws. Some find it useful to have a few degrees of fleam on their rip saws.

Smoother, slower cutting saws tend to have a bit more rake, more teeth and more fleam.

There are points of diminishing return on each of these aspects of a saw tooth's shape.

It is the combination of these saw tooth factors the saw maker and filer can alter.

jtk

Jim Matthews
04-06-2014, 4:02 PM
...or a saw can be filed to cut more smoothly, read slower. jtk

Beat me to it.
The difference in time, with my high tooth count saws,
is less than turning around and finding the properly filed saw.

It's nice to have a "jack" saw that manages many things well.

So what if it takes 30 strokes instead of 22?
If I can crosscut without tear out and get really smooth
ripcuts, that's satisfactory.