Thread: Skelton Saws U.K

Ray, I think you have a point, though the relationship to the tooth line in my view is more about getting the power to the people teeth, whereas the grip angle is all about getting that power transmitted comfortably. It's interesting that I only began to consider comfort and the relationship of handles to anatomical limitations in the last 15 years or so, but ageing joints & tendons have a way of altering one's awareness! So now I look at the grip angle first, to set my wrist up so it's working in the most comfortable way, in the position I will use the saw most often. Of course there has to be compromises, because our arms are jointed levers, and we have to make constant adjustments to the bits of our arms to keep the saw moving in a straight line as the arm is extend. Our ability to apply even power for the full stroke involves a lot of computations and smooth adjustments up there in the grey matter! That means the relationships between all of the components has to be a compromise. Throw in individual body shapes and preferences and it all gets too hard to make more than general rules, for me. I have arrived at certain grip angles by trial and error (especially the latter!), but it's interesting to me that my preferred grip angles tend to roughly match those on several very old saws I've had or used. I'd like to think it's not just because I got used to those handles, but maybe it is. I'll have to think about it some more...

Anyone else want to chip into the debate?

Cheers,

Hi Ian, I am in the same school of thought as Ray on this one. That there is a direct relationship between the hang of the handle and the length of the blade. Where I would differ slightly with Ray is that I prefer the index finger points more towards the front toe of the toothline than towards the centre. But in saying this, I also acknowledge Rays practice does offer some other positives to the performance and feel of the backsaw.

Stewie;

There is also the height of the handle in relation to the spine.
So a handle with more hang and set higher may still have your finger pointing at the same spot on the toothline as a handle with less hang and set lower.
Combine this with different amount of cant to the blade and quite differently configured saws may be quite similar in feel.

Originally Posted by hiroller

There is also the height of the handle in relation to the spine.
So a handle with more hang and set higher may still have your finger pointing at the same spot on the toothline as a handle with less hang and set lower.
Combine this with different amount of cant to the blade and quite differently configured saws may be quite similar in feel.

Well, that is precisely why I take a different approach.

I don't want my saws to be similar in feel, I want 'em to feel like they are just right for what they get used for. I really don't mind all that much where my index finger is pointing, so long as it has something to rest against & is out of harm's way. What's important to me is that my wrist is neither twisted up nor down on the majority of power strokes, but is straight, & all those carpal bones are absorbing the force evenly. Since I use different saws in different positions, I want grip angles to suit.

Maybe it's the biologist's vs the engineer's mindset?

Setting hang angles the way Ray & Stewie do is going to give you a set of saws that have a common 'feel', perhaps, & if that's your main goal, then all is good. As I always say, whatever works for you, works.....

Cheers,

Well, I'll chip in with a third view: the hang angle is a function of where we wish to direct the effort in pushing the saw.

The hang angle of a 9" dovetail saw does not alter when the plate becomes 12". It alters with the rake and size of the teeth, because these determine the function of the saw. The hang for a tenon saw will be different to a dovetail saw ... if the teeth on a dovetail saw are, say, 15 ppi and zero degrees of rake, while the tenon saw is 10 ppi and 10 degree of rake. You would want to lower the hang angle for the latter, not simply for the length of the plate, but because it is easier to push.

On a light dovetail saw, such as the Gramercy, the hang is higher than average. This directs more downforce without extra effort, keeping the saw light. This is needed in a saw which is not just light, but also has a high tooth count (19 ppi).

At the end of the day it is all about balance and control - a bit more here and a bit less there ..

Regards from Perth

Derek

Interesting - that now makes three quite different philosophies behind determining grip angles. This discussion so far has shown there's a much broader school of thought behind what I thought was a fairly straightforward bit of applied biomechanics. Looks like I was dead wrong (again!).

I'd not even considered Derek's point of the grip angle affecting the pressure that can be applied, before. Of course it will, now I think about it, but it isn't something I would have consciously sought to build-in when setting up a handle. Having a father, & other old blokes who would sternly admonish us for 'leaning' on any saw in my impressionable youth, light cutting pressure is something I'm very careful of, & I expect a saw to cut pretty much 'under its own weight'. Of course a small saw won't entirely, about the only saw that really does that is a thumping great 8 footer docking a felled log. There is always some downward force applied, no matter how lightly you think you saw, but I find a saw cuts best (& is far less likely to bind if lightly set) if you keep that pressure to a minimum. When I find a saw needs conscious pressure to cut, I reckon it's high time to get out the file.

A handle designed to minimise pressure transfer might be preferable to me in some situations. Dunno, but it's one more aspect to explore......

Hmmm, just as I was about to hit 'send', I thought of at least one situation that makes a liar of me, already. When starting a horizontal cut on a wide board, where you can't or don't want to angle the saw to start on an edge (e.g., cutting the sides for a sliding dovetail against a guide), it takes extra pressure to make the saw cut & keep it to the line. There are probably other situations I can't think of, immediately, but that's enough to show there are no absolutes in this life!
Cheers,

The close interaction between hang angle and the length of the saw plate is explained very well by Isaac Smith on his web site.

http://www.blackburntools.com/blog/c...d-saw-handles/

http://www.blackburntools.com/blog/f...f-hang-angles/

Stewie;

As all have pointed out. This is one of those discussions that is never resolved to the complete satisfaction of all. There are many variables as to what hang angle a particular person desires with respect to their own body mechanics and preferences. This is exactly why I make three different hang angle dovetail saws. 45, 38*, and 32*. When sitting at my bench, I prefer my 32*, standing up right --my 45* and if leaning forward the 38*. I am not such an expert at dovetails as to have a specific preference at this point. No doubt because I spend more time making them than using them. So one must always consider the hang angle and how aggressive you wish your saw to be, when determining what rake to file the teeth. With respect to the thrust vectors involved there is also a pic or two of the difference on my web site under "Ramblings" My apologies I no longer have much written on the subject. Updating some of the site. But the jist is: If all other things are equal ( rake, fleam, set ) the 45* hang is the most aggressive, the 38* next, and the 32* the least aggressive. Again... assuming all other variables being equal. So, is it any wonder there are so many different hang angles on saws? Either way I do like the design of the Skelton saw. It will be interesting to see where he/ she takes the larger saws. But it is definitely more Euro than Western to my eyes. Partly due to the hang angle, I suppose. I certainly wish him/her well. Best wishes, Ron

Thanks for those links for Isaac, Stewie. I am right in the middle of a similar article, but for handplanes. You may (or not!) recall that I have written on this subject before for both backsaws and handplanes. It is a topic of great interest to me. More later.

Essentially, Isaac 's views and mine overlap. We both consider the interaction important between force vectors and the angle the saw plate is held relative to the rake of the teeth.

Edit: Ron's post and mine overlapped, so I will include him here as well. Hi Ron!

Regards from Perth

Derek

Good to know its been of assistance to you Derek.

I dont recall reading your entry on backsaws but when I get the time I will have a look at it.

regards; Stewie.

Originally Posted by derekcohen

... recall that I have written on this subject before for both backsaws and handplanes.

Hi Derek, Your link isn't working.
Thanks,
Rob

Hi Rob. The link is working fine for me.

Stewie;

I've already said my piece, so this is my last post on the subject - promise!

While in general I think it's pretty reasonable, it seems to me there are a couple of inconsistencies in Mr. Smiths monograph. What I find most puzzling is that he shows two very similar sawing stances (for different saws), but calls one wrong & the other right.

At the risk of being a tedious bore, I think everything he concludes can be equally covered by my hypothesis that you set the hang angle for a 'neutral' wrist when the saw is held in the position where it will be most commonly used. It will still be useable in other positions, just not as comfortably or 'naturally'. Try this for yourself: if you have normal joint mobility, you will find twisting your wrist down from the neutral position is easier, and it has a greater range than twisting it the opposite way. So it will be easier to use a saw that is hung a little too high (i.e. the handle is rotated more towards a horizontal position), than too low for the specific task(s).

Point two is that you should most certainly get your body into a comfortable position if you plan to saw for more than a few minutes. 'Comfortable' for me means my back is reasonably relaxed & not stooped anything like to the degree in Isaac's pics. Maybe it's my more advanced years, but I would soon have a n'orrible sore back if I was to work as shown in a couple of his illustrations for very long! The sort of sawing we're talking about here is pretty much all arm action, you don't add any significant momentum from your upper body, unlike when using a bench plane, so you don't need to 'put your back into it' as you do for a bench plane, for e.g.

Point three. On varying tooth rake angles to control bite. This has been done since forever, but hitherto I have always thought of it as primarily to control bite in harder and softer woods. You could certainly use rake angles to alter 'bite' to compensate to some extent for a mismatched handle, but I think I'd probably change the handle, first...

OK. I promise to be quiet.....
Cheers,

Originally Posted by planemaker

Hi Rob. The link is working fine for me.

Stewie;

Hmm.. didn't work for me either, but then I noticed a colon missing in the url just after the http.. try this one. http://www.inthewoodshop.com/Commentary/


Back on topic.. I think it would be a good exercise to do a graph of hang angle vs length of historical saws, and see how much scatter there is, I see the effect of stance, work height, rake angles etc, as all important factors but second order effects when compared to the primary variable which is blade length..

When the blade length is very short, the second order factors become larger, so I think we see more variability in hang angles with 8" dovetail saws, than we do in say 14" tenon saws.

Interesting subject, but at the end of the day, it's what works best that counts.

Ray