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IanW
2nd August 2012, 08:33 PM
In another thread, I said I was thinking about a saw for cutting the sides of the trench for sliding dovetails. So during a recent spate of sawmaking, I decided the time had arrived to put my idea into practice.

Ok, so I began with the blade. Another scraper from Bunnings met the cutoff wheel, to make it shorter and narrower. I used the top so that existing holes could be incorporated in the depth-adjustment slots. (pic 1). Actually, the holes are too big, so they over-run the slots & although out of sight, they can catch on the clamping bolts when trying to make fine adjustments, which is nuisance, so I would cut fresh slots in future. The blade is 225mm long, 10 tpi, and has a bare minimum of set (it is only going to have to cut to about 6-8mm deep, max). It is also slightly crowned - about 1.5mm down at each end compared with the middle. This, I reasoned, would make it easier to start and clear sawdust better. It means the cut will be a teeny bit shallow at a blind end, but I can live with that.

Now, I wanted to keep it very plain & simple, so the blade was to be fitted between two pieces of wood, with the top shaped into a 'hot dog' for a handle. The idea was that it would be easy to flip the saw & use it in either push or pull mode. Fortunately, I tried it out before wasting time shaping the handle (pic 2). It was a miserable failure. Having all the weight directly over the blade, and trying to push or pull it from that position caused it to bite too hard and either stall, or jump out of the kerf. It was not going to work that way!

Rethink time. I tried holding the blade at one end between my fingers, and it cut fine, so the answer seemed to be, just make a more conventional handle, with very long cheeks. And that's what I did. Wasn't easy making such a long slit & keeping it perfect all the way. but by scribing it with my slitting saw, & being careful, I managed it. So here is the working prototype (pics 3 & 4). The blade depth is adjusted to the thickness of the guide, plus the depth of the trench, and the cheeks than act as an automatic depth stop (pic 5). I was a bit nervous that the three saw bolts might not hold the blade firmly enough, but all it takes is a light twitch-up to hold it as solid as a rock.

So far so good.....

IanW
2nd August 2012, 08:36 PM
Well, the proof of the pudding, as they say…..

I cut a short sliding D/T to see how it all worked. The first thing I noted was that my marking-out procedures need a bit of smartening up. I am too used to doing these with the router and a simple jig, so it took a few heavy head-scratches to lay out my joints, but eventually I worked it out. I set up my simple fence to cut the sides of the trench, which has 1mm taper across the 120mm wide bit of scrap on the angled side, which would normally be the ‘down’ side of a shelf or carcase component.. (pic 1)

A bit of serendipity is that the bevel on the saw cheeks (which is matched to the bevelled side of the trench), means that the vertical cut and the angled cut end up as close to the same depth as you could wish for. So a bit of chiselling out of waste, cut the matching D/T and Bob’s your relly!

Pics 2 & 3 show the pieces after a couple of trial fittings. It’s sitting proud by a few mm after being slid firmly together – a couple of firm taps drove it solidly home.

All good on that quick test-run – it will be a another story when I try a couple of full shelf-width D/Ts! But this has shown me I need two things – a bit of practice at laying out, and a router plane. I did have one for a while, but never used it, so sold it off. Now I’m thinking of getting a couple of LV blades & making myself one. Darn it – I thought I had all the tools I ever needed…….
:; :roll:

Cheers,

Howard Pollack
3rd August 2012, 01:13 AM
Ian- You do very nice work! -Howard

derekcohen
3rd August 2012, 02:10 AM
Hi Ian

Nice saw, especially as there is a developmental process involved.

I would still call this a stair saw, especially as it is breasted and capable of starting the cut in the centre of a board.

I am not sure that I have the skills to use one to saw accurately for either a dado or a dovetail, and prefer a guide (which I use with a mitre saw - you've seen this before so I shall not post a picture of it, but the link is here (http://www.inthewoodshop.com/Furniture/SlidingDovetailsbyhand1.html)). The question is, can you design a guide for this saw?

Regards from Perth

Derek

IanW
3rd August 2012, 09:06 AM
I am not sure that I have the skills to use one to saw accurately for either a dado or a dovetail, and prefer a guide ..... The question is, can you design a guide for this saw?

Hi Derek yes, the principle is the same as a stair saw. The crowning is slight, just enough to make it easy for initial kerfing along the cutting line. I just guessed the amount, thinking I'd keep it minimal to begin with, because of the aforesaid problem with having a slightly shallower cut when doing stopped trenches. But the amount I gave it is adequate, and it's very easy to start anywhere along the line.

It does have a guide, albeit a very simple one (see first pic in 2nd post) P'raps I should have referred to it as a 'fence'? I simply ripped a piece of wood with a right angle one side, and the dovetail angle on the other. I was prepared to experiment a bit with fence heights, but the 20mm piece I started out with felt right, so that's what I'll stick with for now. You just hold the saw firmly against it with your left hand as you saw. The narrow, stiff blade makes it very easy to feel when it is against the fence. The almost zero set prevents the saw from chewing up the bottom of the fence, but I imagine it will scuff it up a bit over tme - no worries, it takes about 2 minutes to make another. :U

The cheeks of the saw are planed to the complementary angle, so that they meet the fence at full depth on the angld cut. When sawing the vertical side of the trench, the side of the fence is a little shorter than the angled side, but the inside of the cheeks hits the fence sooner, so the cuts end up as close to the same depth as my eyes can discern. After it happened, I did a bit of mental trigonometry, and realised that that is how it should be, of course, if the angles are complementary. But I won't claim I thought of it in advance!

You under-rate your skills, my lad - if you can cut accurately with that great weapon you used (I would make a right mess with something like that!), you would find this saw a breeze. It's very easy to position, everything is in line & close to the action, and as I said, you can easily feel when that short blade is snugged up against the fence. I produced two near-perfect cuts on the first try, and I certainly don't think I am any more skillled with a saw than you are.

Looks like I will have to send you one for evaluation & further development, before we sell the patent rights to Veritas or LN??? :;

Cheers,

silentC
3rd August 2012, 10:08 AM
I would still call this a stair saw
Surely the inventor can call it whatever he wants ;)

A couple of questions:

1. Could you make the handle in two pieces to make it easier to construct, and either laminate two halves together to arrive at what you have there, or just have one side of the spine as a separate piece and have it all held together with the bolts?

2. What's the reasoning behind the half-dovetail? Is it just because it's easier to only have to cut one sloping side?

ch!ppy
3rd August 2012, 02:54 PM
2. What's the reasoning behind the half-dovetail? Is it just because it's easier to only have to cut one sloping side?

in a way you could say that, but really in many applications (shelves for instance) thats all that is needed to do the job, to stop the sides from bowing or cupping outward, so the theory is if thats all thats needed then why do more. the dovetail housing joint in its most basic form would not have the added shoulder (or rebate) to the top of the shelf as in the pic above (its laying on its side if representing a shelf), it would be left square and the housing in the side trenched a little wider to fit, adding the shoulder to the top can help hide a (finished) gap if the taper on the dovetailed shelf or housing are somewhat mismatched (loose if you like).


cheers
chippy

Woodwould
3rd August 2012, 03:16 PM
As usual, you've produced a lovely looking saw Ian, but I don't understand why a dedicated saw is required for cutting sliding dovetails. I may be missing something vital: I'm a self-taught 'cabinetmaker', so it's not beyond the realms of possibility.

I begin the angled cut on the edge of the board with an ordinary back saw and saw it full depth to start with so my eye 'learns' the necessary lean angle. After that it's just a case of keeping sawing until the cut is done.

How does your crowned blade design help? Why start sawing in the middle of the cut? Surely if you begin sawing on the edge it would be straightforward and wouldn't require a bevelled wooden guide.

silentC
3rd August 2012, 03:35 PM
thats all that is needed to do the job
Good enough reason in my book ;)

IanW
3rd August 2012, 07:10 PM
Surely the inventor can call it whatever he wants ;)


Maker, silent, not inventor - it is indeed based on "stair saws".


A couple of questions:

1. Could you make the handle in two pieces to make it easier to construct, and either laminate two halves together to arrive at what you have there, or just have one side of the spine as a separate piece and have it all held together with the bolts?

2. What's the reasoning behind the half-dovetail? Is it just because it's easier to only have to cut one sloping side?

Answer to 1, "Any of the above". :U I don't see why any of those methods would not work just as satisfactorily. I did it in one piece because that seemed like the best option for me, but if you don't happen to have a haandy slitting saw set up like mine, a two-piece construction might be the btter way to go.

Chippy has already answere Q2 as well as I could. When making S/Ds with router, you of course end up with angles on both sides. That's a theoretically stronger joint in terms of resisting tensile forces, but whether the difference matters in practice is a moot point. It doesn't complicate things overly to do angles both sides if you really want, & if I were doing this joint for say, the bottom of a cabinet, I would probably make both sides angled.

But of course, having to deal with only one angled side is easier. I would always rebate the 'top' side, myself, simply because it is easier to make a clean shoulder on the shelf piece and get a close-mating joint than to rely on getting the top side of the trench perfect, given that you are guddling away in there with a router plane or whatever......

All fair questions, & I hope that addresses them...
Cheers,

IanW
3rd August 2012, 07:39 PM
As usual, you've produced a lovely looking saw Ian, but I don't understand why a dedicated saw is required for cutting sliding dovetails. I may be missing something vital: I'm a self-taught 'cabinetmaker', so it's not beyond the realms of possibility.

I begin the angled cut on the edge of the board with an ordinary back saw and saw it full depth to start with so my eye 'learns' the necessary lean angle. After that it's just a case of keeping sawing until the cut is done.

How does your crowned blade design help? Why start sawing in the middle of the cut? Surely if you begin sawing on the edge it would be straightforward and wouldn't require a bevelled wooden guide.

WW - all fair comment, & reasonable questions.

No, I don't need a dedicated saw, but I wanted one, and becaause I can, I did..... :U

True, you can make a long straight cut across a board with a backsaw. However, if you look at the pics in the link Derek posted, you will see that he had a bit of trouble cutting to his scribe line. I have at least as much trouble getting a long saw with teeth in a straight line to follow a long cut from such a shallow attack angle. The method you describe is pretty much how I have done it previously, when trenching for shorter S/Ds such as for drawer dividers & so forth.

You can also make a legitimate argument that the cut needn't be absolutely perfect - anyone who has done a few S/Ds will know that they can be a bit rough in places, but the joint can still snug up nicely enough, and any ragged bits should be well hidden by the over-riding shelf edges.

However, it just seemed to me that a saw with a shorter, narrower blade, a low centre of gravity, and slight crowning would make the task a whole lot easier, and in my short test, that is exactly what it did. I was able to start the saw at the right angle anywhere along the line, & having an automatic depth stop, & not being forced to guess when I am at depth is worth the effort alone. The shorter, crowned blade allows me to cut a stopped trench closer to the blind end, meaning less chiselling & mucking about at the stopped end.

I would probably still use my regular D/T saw to cut the sides for a 50-60mm long drawer-runner trench, for e.g., because I couldn't be bothered having to muck about & clamp on a fence for such short cuts, and the S/Ds for table legs mating into a round pillar can only be done by eye, since there's no practical way of using a fence in that situation. But this saw makes doing 400-500mm long cuts much more accurate, & easier than any method I've tried, apart from a router & jig.

So, I don't think everyone need rush out & make themselves such a saw - if you only plan to make few S/Ds in your life, it's not worth thinking about. But if you just happen to like making saws........... :D

Cheers,

Woodwould
3rd August 2012, 07:46 PM
Fair enough. It's something else I should try some day.

derekcohen
3rd August 2012, 07:49 PM
How does your crowned blade design help? Why start sawing in the middle of the cut? Surely if you begin sawing on the edge it would be straightforward and wouldn't require a bevelled wooden guide.

WW, I think that there the crowned blade is a throwback to forming a housing joint in the middle of a board. Of course we are talking about a dado and not a sliding dovetail (you cannot have a dado in the middle of anything). The stair saw is crowned for this purpose, and the design is common to both Western and Eastern saw users.

With a sliding dovetail the trench needs to be entered from one edge (at least). There is no need for a crowned tooth line. I have also used a dovetail saw for stopped dovetails. If, however, the dovetail extends the full width of a board, then I use a long mitre saw. This follows the line more easily.

You also make an interesting point about sawing from the edge - I assume you mean that you create a saw line (which becomes a guide for itself) from the marks on the edge of the board. I've not thought to do that before.

Regards from Perth

Derek

IanW
3rd August 2012, 07:59 PM
.....
You also make an interesting point about sawing from the edge - I assume you mean that you create a saw line (which becomes a guide for itself) from the marks on the edge of the board. I've not thought to do that before.


Derek, when doing something like this table pillar, I could not think of any other way of doing the trench sides. Even if you chisel out some of the waste at the end, it's still not possible to get the cut to full depth at the end. You still end up doing a fair bit of paring, but at least you have established the right angle....

Cheers,

Woodwould
3rd August 2012, 11:43 PM
You also make an interesting point about sawing from the edge - I assume you mean that you create a saw line (which becomes a guide for itself) from the marks on the edge of the board. I've not thought to do that before.

Regards from Perth

Derek
Until someone else recently mentioned using an angled guide, I knew no other way of doing it. It's how I begin the majority of saw cuts. How else do you saw half-blind dovetail sockets?

pmcgee
4th August 2012, 03:19 PM
... and the S/Ds for table legs mating into a round pillar can only be done by eye, since there's no practical way of using a fence in that situation.

That seems uncharacteristically pessimistic of you Ian :)

One might imagine a jig that wrapped roughly 270o around the base of the post, with bolts to lock against (one of) the flats, with the right amount left to make the fence to cut 3x one side of the S/D.
If you were real clever, it might flip and do the other sides too.

Also - you could just pin-nail on a miniature version of your current fence, and knock it off after.

Not saying it's practical :) ... maybe actually a deserving job for the router table. :o

Cheers,
Paul

derekcohen
4th August 2012, 10:11 PM
Until someone else recently mentioned using an angled guide, I knew no other way of doing it. It's how I begin the majority of saw cuts. How else do you saw half-blind dovetail sockets?

Why WW, I use this guide for my dovetail saw ...

http://www.inthewoodshop.com/Furniture/SlidingDovetailsByHand1_html_m4221d13d.jpg

No, really, I have no difficulty sawing to a line with dovetails, half-blind or blind, however it did not occur to me to treat a sliding dovetail in the same manner. Mmmmm ...

Regards from Perth

Derek

homesy135
4th August 2012, 10:14 PM
I couldn't remember where I had seen a fellow cutting a sliding tapered dovetail on the net when I first saw this post or perhaps a recent related post asking how.

It was an episode of the Woodwright's Shop. Here is the link to the video. It runs for 27 minutes.


Video: The Case for Books | Watch The Woodwrights Shop Online | UNC-TV Video (http://video.unctv.org/video/1772022578/)

pmcgee
5th August 2012, 05:36 AM
Another great St. Roy video.

Thanks Paul - I love the 'pared-back' way he works. :)

It didn't occur to me before, but I guess you could cut the dovetail half of the groove/dado straight and put the taper on the vertical side?
If there isn't a practical consideration I've missed, I would have thought that would be a bit easier to execute (?)

Cheers,
Paul

IanW
5th August 2012, 09:09 AM
Paul, you over-think things, I'm afraid. There are so many operations that can be done very accurately by practised hands. Until recently, at least, there have been some things that could only be done sufficiently accurately by hand such as grinding those humongous reflector mirrors for celestial telescopes. "Practise" is the operative word....... :U

Cheers,

Woodwould
5th August 2012, 10:37 AM
I believe you've hit the nail on the head Ian: Many amateurs failing to achieve the results they expect from techniques they've seen others master, resort to guides, jigs and similar incompetent aids with the result they gain no practice in the technique that they should be persevering with and therefore never gain any proficiency at it.

pmcgee
5th August 2012, 01:45 PM
Paul, you over-think things, I'm afraid. There are so many operations that can be done very accurately by practised hands. Until recently, at least, there have been some things that could only be done sufficiently accurately by hand such as grinding those humongous reflector mirrors for celestial telescopes. "Practise" is the operative word....... :U

Cheers,


I absolutely agree with you and WW about the simplicity with which work can be performed - with practise. That video that Paul posted is a perfect example.

Seeing Roy and Frank Krausz work ... that captures my ideal of workmanship.
Those videos of the French cabinet-makers, and recently of the old Irish makers of boats and carriages ... I love that.
To see a, as you say, practiced hand quietly and efficiently working - without a plethora of new tools and jigs - is a delight to me.

But, your words were that there was no practical way of using a fence in that situation, and unnecessary or not, the idea of a semi-doughnut jig that could be rotated and reversed to fence all six cuts appealed to me as a concept. And who knows, the idea might park itself into someone's brain and be turned into something else actually useful in a completely different context. Well ... It's never happened with any other idea I've had, but you never know ... :)

And yes to the overthinking. But it keeps me off the streets, so it's approved by the local council.
:D

Cheers,
Paul

pmcgee
5th August 2012, 02:48 PM
(For you Ian ...) Telescope Making video #4 of 4 by Rich M - YouTube

:)

IanW
9th August 2012, 07:37 PM
After some more tinkering, have decided my new dovetail/stair/dado - whatever saw is a keeper, so I rearranged my "overflow" saw cupboaard to accomodate it.

I suppose I could squeeze another small saw or two in, at a pinch, but it might be hard to extract them iff I do - shades of Studley, here.... :U

Cheers,

sdbranam
10th August 2012, 11:13 PM
I couldn't remember where I had seen a fellow cutting a sliding tapered dovetail on the net when I first saw this post or perhaps a recent related post asking how.

It was an episode of the Woodwright's Shop. Here is the link to the video. It runs for 27 minutes.


Video: The Case for Books | Watch The Woodwrights Shop Online | UNC-TV Video (http://video.unctv.org/video/1772022578/)

:2tsup: You guys do great work! As usual, Derek's article on sliding dovetails is excellent.

Thanks for the link to Roy's video. When I took a class from him last week at Lie-Nielsen (TobyC posted a link here to my blog post on it), the sliding dovetail was the last item on the agenda, but we ran out of time before we got to it. It's also in his books "The Woodwright's Guide" (for shelf) and "The Woodwright's Apprentice" (for 3-legged table and chair bottom cross-cleat).

pmcgee
12th August 2012, 05:50 AM
Just thinking - after posting the thread about the strength of unglued dovetails - that the half-straight-sided (sliding) dovetail wouldn't have the (exact) same deformation behaviour. I suppose if it was given the opportunity it would like to rotate out of its socket/groove with the angled edge as the pivot area.

Does that in practice effect which way you would point the angled side (up or down) to a half-dovetailed shelf board that might be destined to be overloaded with heavy books?

I'm guessing that the angled edge upwards and shouldered on the bottom would be the preferred arrangement? or a full sliding dovetail?

Thanks,
Paul

IanW
12th August 2012, 07:31 PM
Paul, in the grand scheme of things, I doubt it matters a hoot which way the angled side goes. Whatever the strength, of just about any dovetail, lapped, half-lapped or sliding, it's adequate for the purpose if used in the way that experience & time have shown works. Tests of strength under different conditions are illuminating, and interesting, but I'm not sure how they advance existing empirical knowledge...... :;

Cheers,

pmcgee
12th September 2012, 07:57 PM
Another design.

The Part-Time Woodworker: My New Rock And Roll Saw... (http://theparttimewoodworker.blogspot.com.au/2012/04/my-next-major-project-is-new-combo-tool.html)

http://2.bp.blogspot.com/-S6TQge0OFIg/T33hgSWzy6I/AAAAAAAAA2A/IdzqO-0YGzY/s1600/dovetailSaw.jpg

ch!ppy
12th September 2012, 08:43 PM
it would be an interesting saw to use, and to re-sharpen and maintain Paul, depending on which angle you hold the saw at the tooth angle (rake) will be different all along the blade (relative to the timber) unless you match it to the curve of the fence!(who would do that!) then you would want to be pretty accurate when jointing or resharpening the blade to keep the distance equal from the tip of the teeth to the bottom of the fence/stop...could be a real pig to push through some nice timber and keep a neat cut, make a mess of it is my first thought (fine for cutting through giprock though), maybe they have this worked out though...thats just my ,ultra, quick take on it without any thought i admit


ps, looks like fancy wood too, maybe zebra and black plastic or maybe zebra coloured plastic, whats it cost?

FenceFurniture
12th September 2012, 09:13 PM
After some more tinkering, have decided my new dovetail/stair/dado - whatever saw is a keeper, so I rearranged my "overflow" saw cupboaard to accomodate it.

I suppose I could squeeze another small saw or two in, at a pinch, but it might be hard to extract them iff I do - shades of Studley, here.... :U

Cheers,

There's plenty of room in there for more saws. Just turn every second one upside down.

Cheers
Brett (PhD in AR)

pmcgee
12th September 2012, 10:09 PM
it would be an interesting saw to use, and to re-sharpen and maintain Paul, depending on which angle you hold the saw at the tooth angle (rake) will be different all along the blade (relative to the timber) unless you match it to the curve of the fence!(who would do that!) then you would want to be pretty accurate when jointing or resharpening the blade to keep the distance equal from the tip of the teeth to the bottom of the fence/stop...could be a real pig to push through some nice timber and keep a neat cut, make a mess of it is my first thought (fine for cutting through giprock though), maybe they have this worked out though...thats just my ,ultra, quick take on it without any thought i admit

ps, looks like fancy wood too, maybe zebra and black plastic or maybe zebra coloured plastic, whats it cost?

There's a link there in that post at the top to the blog, [[ The Part-Time Woodworker: My New Rock And Roll Saw... (http://theparttimewoodworker.blogspot.com.au/2012/04/my-next-major-project-is-new-combo-tool.html) ]] although it doesn't stand out the way things are at the moment ... it explains that the fence does match the blade - but you make a good point re sharpening. He's working it up with Matt Cianci - newly professional US sawsmith - apparently very good according to reports.
Looking to make it in ebony I think it said.

I only came across it cos he started a moulding plane enthusiast site ... Vintage Woodies (http://vintagewoodies.wordpress.com/) ... but became discouraged I think.

Cheers,
Paul

IanW
13th September 2012, 10:08 AM
Another design.

My New Rock And Roll Saw...

I guess that's what you call convergent evolution!

Thanks for bringing that to my attention, Paul - I was feeling a bit silly because my saw was more elaborate than it needed to be, but this one makes mine look very crude! :U

It's apparent we both set out to solve the same problem, viz., how to saw to a fixed depth on a "blind" cut, and opted for a similar principle. We both opted for a curved blade, but I used a larger diameter curvature, which means mine probably can't work as close to the end of a blind socket as this one should. Mine probably doesn't clear the sawdust as well on a long cut as the 'rock & roll' version, but the flatter blade makes the saw more manageable, for me. I decided it was simpler to make the blade exposure adjustable and let the saw body be the depth stop when it hits the fence, rather than make a separate external fence.

I don't think there would be a huge problem with the rake angle of the teeth, just maintain an angle matched to an approximate tangent to the curve as you form them, but you would certainly have to be careful to keep the curve pretty close to the curve of that fence.

I didn't put quite as much thought into dressing-up my saw, I must say......:U

Cheers,

ch!ppy
14th September 2012, 01:27 PM
I don't think there would be a huge problem with the rake angle of the teeth, just maintain an angle matched to an approximate tangent to the curve as you form them, but you would certainly have to be careful to keep the curve pretty close to the curve of that fence.

I didn't put quite as much thought into dressing-up my saw, I must say......:U

Cheers,

maybe, maybe not, you wouldn't really know until you used it. sometimes these things sound good in theory but don't work so well in practice, if you have ever used curved saws, like a floor saw for instance you would know what i'm talking about, the curve is great (needed) for starting mid way but using the tip of the saw and such it can bite in and make it a bit (sometimes a BIG) of a pita to cut, you preserver of course and you get it to work but using a regular saw is much nicer and if you have that option its the preference, makes a neater cut usually too...its not the same as putting a slight crown on the blade like you have done and using it (mostly) flat, its hard to explain here, but in practice you can tell what i mean straight away using a curved blade when using the tip with the handle up high, especially if the teeth are sharp they bite in and its hard to get the cut going smooth, less teeth per inch the harder too naturally...looking at the pic again (i only looked real quick the other night) it might not be too bad, the blade doesn't look a 'lot' curved, the fence throws me a bit, makes the curve look bigger than it might actually be to my eyes (particularly the other night at a glance) my impression was ,whoe, thats a big curve, perhaps the handle position exaggerates it a bit to me, if the tpi is fine it may work ok but it could still could be a pig to use as well, like i say, you would have to try it, i think i'd much prefer to stick with my way or the traditional way for blind stopped sliding DT, i wouldnt even consider it for through cut sliding DT


IanW
Paul, in the grand scheme of things, I doubt it matters a hoot which way the angled side goes


given the choice its usually better to put the flat side toward the end grain, tad bit stronger that way



cheers
chippy

IanW
14th September 2012, 07:51 PM
... my impression was ,whoe, thats a big curve, perhaps the handle position exaggerates it a bit to me, if the tpi is fine it may work ok but it could still could be a pig to use as well, like i say, you would have to try it, i think i'd much prefer to stick with my way or the traditional way for blind stopped sliding DT, i wouldnt even consider it for through cut sliding DT....

Hi Chips, that was my first impression, too, & still is! I was actually referring to forming the teeth when I was talking about rake angle not being a problem - the main challenge is laying out the spaces on the curve so that the tpi stays constant. I agree that in use you would need to rotate that curved saw evenly on each stroke to maintain any semblance of a smooth cut - it doesn't look like an easy animal to master to me, either, but as you say, unless you had it in your hands, you couldn't really say. A high tpi would certainly help, but also defeat the purpose to some extent by clogging more & cutting slower.

I can't say I've given my saw a real pounding, yet, but have used it a bit & I like it. It does what I expect of it quite well, & is easy to keep straight & true against a guide. Time will tell how much use it gets, but I expect to do lots more work without burning electrons now that I have the luxury of time....

I do have a couple of curved-blade saws, in fact, but they are the opposite of floor saws, as they are filed to cut on the pull stroke. I use them for forming the 'u' shaped slot in my saw handles. I've never used a floor saw, but have held a couple in my hands & thought they looked like a bit of an ugly thing to have to do any accurate work with, so I'm not surprised at all by your dislike of them....

Cheers,