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Chris Griggs
01-11-2012, 2:47 PM
I just wrapped up doing a bit of refilling on a 16” 12ppi Disston backsaw. Recently, there’s been a small amount of discussion about the combo/hybrid filed Gramercy Sash and the Bad Axes, as well as combo filing in general. FWIW, this post will present you with NO new information. It is nothing that hasn't been said or done before, but I thought I'd share my experience nonetheless.

First let me say, I’m often not a fan of multi-function tools, as they tend to do a few things pretty well, but nothing exceptionally well. However, with backsaws, hybrid filing interests me for a couple reasons. The first being that I have limited space, both on and around my workbench, so even one extra saw that is out on the bench can get in the way. The second being that small toothed saws (around 12ppi or higher), even when filed with no fleam, are pretty easy to crosscut with compared to larger toothed panel/hand saws, so tweaking them to do double duty seemed quite plausible.

Anyway, long story short. I got so intrigued with combo filing on the Gramercy saw, that I decided to file a nearly identical geometry into my 16” 12ppi Disston. That is, I filed it with about 5 degrees of rake and around 7.5 degrees of fleam. Wow! Mr. Moskowitz is onto something. I have questioned several times on this forum the practicality of the combo filed saw he sells, and after filing a saw with that same geometry, I am here to say that my doubts have been permanently put to rest.

There seems to be some magic place (on fine toothed saws) in between 5 and 10 degrees of fleam, where one gets:

1) A saw that rips extremely smoothly, with little to no noticeable loss of speed and…
2) a saw that crosscuts probably 95%, as smoothly and quickly as one filed with a more standard 20 degrees of fleam.

I really like this filing, and can honestly say that the saw rips as well as any rip saw I’ve used (not that I've used that many) and what it gives up in cross cutting (compared to my dedicated LN 14” xcut) is negligible.

As one would expect for ripping, this filing works particularly well in harder woods. When I used it in white oak it immediately became apparent to me why many people will add 2-5 degrees of fleam to saws that they plan to use as dedicated hardwood rippers. The fleam REALLY smooths out the cutting action, to the point where it actually felt like the fleam was making it rip faster in the oak. This also seemed to carry through in more moderate hardwoods (walnut and cherry). In softer wood (poplar) the fleam did make the saw feel ever so slightly less aggressive (no surprise there), but again I didn’t notice any dramatic decrease in speed, it just kind of felt less aggressive.

Similarly for crosscutting hardwoods, it seemed to cut just as nicely as my dedicated xcut. The resulting surface it leaves is every bit as smooth. The only time I noticed any loss of performance (compared to the LN xcut) was in the softer poplar, where it felt a little sluggish and may have left a little bit more splintering on the bottom/exit face of the board (I'll need to do more testing/comparing to say for sure though)

I hope folks find this information helpful. Based on this experience, I would say to anyone who has been on the fence about purchasing or filing there own a combo/hybrid to give it go. If I can get a saw to function so well as both a rip and xcut, then surely Mr. Harrel and Mr. Mowskowitz, who actually know what they're doing, must be offering something pretty fantastic.

I think you'll be pleasantly surprised how well a saw can be made to both rip and xcut - I know I was!


Cheers!

Chris

Archie England
01-11-2012, 3:11 PM
Thanks, Chris!

Jim Koepke
01-11-2012, 3:12 PM
Thanks for the write up Chris.

It makes me want to go out and try it on one of my rip saws.

I got a lot of ripping to do.

jtk

Chris Griggs
01-11-2012, 3:29 PM
Thanks, Chris!

I'll bring it over for you to play with this weekend. You'll have to post back here to deny or confirm my observations.

Chris Griggs
01-11-2012, 3:37 PM
Thanks for the write up Chris.

It makes me want to go out and try it on one of my rip saws.

I got a lot of ripping to do.

jtk

Glad you liked it. Give it a try. If nothing else you'll love it for ripping in very hard woods.

Jessica Pierce-LaRose
01-11-2012, 3:51 PM
I just sort of figure all my hand filed saws already are "combination" filed - while I've gotten pretty decent at filing, once the teeth are that small, I doubt I'm perfectly square every time.

I'll have to give it a try, but I wonder about the true benefit sometimes - if it's a saw cut where the finish matters, like a tenon shoulder, I'm usually knifing all the way around the cut anyway, so if I make the knife line a little deeper and stay on the right side of the line, it usually works out okay, and if the cut edge is a crosscut that's going to show, I'm probably going to shoot the ends as it is.

That's just my gut reaction - not to discount the advantage of these saws. As I said, I have to try this out sometime.

Chris Griggs
01-11-2012, 4:17 PM
Actually Josh I totally agree. I clean up pretty much every xcut I make with a plane anyway, and thus could probably get away with saws that are onyl filed rip.

And I also agree that hand filing will always add just a touch of fleam. The combo filing I did just deliberately adds a bit more to facilitate easier crosscutting. It's not all that different, but deliberately putting in even this small of an amount does notcibly alter the cutting characteristics (I really wasn't sure if it would until I tried it). BTW, I had previously filed this saw as more of a pure rip, but still with a touch (maybe 2 degrees) of deliberate fleam, which I'm guessing isn't too different from the amount that occurs from the human component of hand filing anyway. The difference between the previous filing is small but apparent. The saw now rips quite a bit smoother in white oak (wasn't my intent but a happy byproduct nonetheless), equally well as it did before in medium hard woods, and perhaps just a touch less aggressively in softerish woods (poplar).

Honestly the improvement in xcutting was pretty minimal but still apparent - it actually crosscut quite well even when it had only a couple degrees of fleam in it. The differnece with adding more fleam in terms of crosscutting was most apparent in starting the cut. It is now easier to start a crosscut and leaves a cleaner edge at the start then before even without a knife line.

Paul Incognito
01-11-2012, 4:41 PM
I've wondered about the hybrid saws since I first heard of them.
Thanks for sharing your observations, Chris. I'll have to give it a try!
Paul

Chris Griggs
01-11-2012, 4:59 PM
I suppose I should also note that the combo filing I used (5 rake, 7-8 fleam), which is based on the filing of the Gramercy Sash, is different then the hybrid filing Mark Harrel of bad axe offers. According, to his website, Mark Harrell files his hybrid saws with 10 degrees and 17.5 - IIRC he says it rips at about 80% of the speed of a dedicated rip saw. I've never used a Badaxe or tried this configuration, but based on those specs, I presume his saw is more of a crosscut that rips well, where as the Gramercey is more of a rip that crosscuts well. Same idea, just slightly different areas of the spectrum. A fast ripping saw that can crosscut was of more appeal to me which is why I went with the Gramercy tooth geometry - different strokes for different folks I guess.

Mike Holbrook
01-12-2012, 3:29 AM
Glad my early experience with the Gramercy Sash saw has been duplicated in this manner. I think you make a good point about this particular filling technique making it easier to start a new cut. I'm not sure yet how one can file 5-8 degrees of fleam? I have a hard time seeing the difference in my Sash Saw's teeth but I can feel it when I saw with it. I am about to order a Gramercy saw vise though and start practicing. I may even try a similar fleam on a larger rip panel or hand saw to see if it helps. I am also thinking about reducing the fleam on a crosscut saw to see what that does.

Thanks for the report Chris.

Chris Griggs
01-12-2012, 8:03 AM
Glad my early experience with the Gramercy Sash saw has been duplicated in this manner. I think you make a good point about this particular filling technique making it easier to start a new cut. I'm not sure yet how one can file 5-8 degrees of fleam? I have a hard time seeing the difference in my Sash Saw's teeth but I can feel it when I saw with it. I am about to order a Gramercy saw vise though and start practicing. I may even try a similar fleam on a larger rip panel or hand saw to see if it helps. I am also thinking about reducing the fleam on a crosscut saw to see what that does.

Thanks for the report Chris.


I did it the same way I file any xcut saw. That is to mark the fleam angle on a sheet of paper and just put the paper behind the saw so I can match the angle when I'm filing. When filing in fleam I've also come to like marking the side of every other tooth with a marker. That way I don't inadvertently file two teeth that are right next to each other and end up filing fleam in the wrong direction. Once I mark every other tooth the filing goes A LOT faster since I'm not constantly looking to confirm that the tooth I'm filing is set away from me, which on small teeth with minimal set can be a pain.

I'd be less inclined to put fleam into one of my big tooth rip saws (or more than 2-5 degrees anyway), since with those I'm really looking for speed of cut more then anything else. I do however imagine that deliberately putting a couple degrees would make cutting in harder woods noticeably easier. I believe Mark Harrell puts about 5 degrees of fleam in all of his rip saws for this reason (not sure though). I have beautiful 26" thumb hole 5.5 point ripper that I picked up last summer for like $2 that I haven't yet gotten around to reshaping the teeth on. Perhaps, I'll try deliberately putting 2-3 degrees in that one. I really need to get a move on that. It's a bit nicer than the the two other old Disston rippers I'm currently using and my plan is to make it go to rip saw.


Anyway, I played with combo filed backsaw a bit more last night and am really quite pleased. Enough so, that I may even sell my 14" LN xcut saw.

Mike Holbrook
01-13-2012, 12:17 AM
I believe the trace the angle on a sheet of paper method is on the video I have. Apparently I need to review it a couple times. Tom Law spray painted all the teeth on his saws. I like the idea of marking every other tooth even better.

My sight may not be great but the amount of fleam in my various crosscut saws seems to vary. It is easy to see the fleam on a 6-7 ppi crosscut, not so easy on 12-19. I have a couple old saws that are hard to tell what they were filed for.

I plan to order a new saw vise from Gramercy, when it gets here I will do a little experimenting too. I just happen to have 5 old saws that need sharpening.