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  #31  
Old 02-17-2019, 08:17 AM
printer2 printer2 is offline
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On printing out the pattern.

http://www.ekips.org/tools/guitar/fretfind2d/
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  #32  
Old 02-17-2019, 09:48 AM
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The device Tadol mentioned in his post costs $75 plus shipping. It is cloned from something I had made about 15 years ago on a CNC machine from a file accurate to .001”. About 2 hours are required to make the sled fixture it is the brains of, and then all that is required is any kind of table saw and one of the .023” kerf blades sold by either Stew-Mac or LMI.

The device cuts any scale length between 24 3/16” and 26 1/2” with high accuracy and complete repeatability. It can be recalibrated infinitely within the ballpark to any of these lengths in less that a minute, and takes me less than 2 minutes to slot the fingerboard.

When I was hand cutting my fingerboards I had nothing like this accuracy (neither do you) and careful layout plus cutting was at least an hours work. LMI’s system works well, I’m told, but requires a new template for each of its limited number of scale lengths.

This idea is something new, yet simple, and people have always been slow on the uptake with this kind of thing, sadly. I laugh every time I use it.
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  #33  
Old 02-17-2019, 10:14 AM
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Quote:
Originally Posted by Bruce Sexauer View Post
The device Tadol mentioned in his post costs $75 plus shipping. It is cloned from something I had made about 15 years ago on a CNC machine from a file accurate to .001”. About 2 hours are required to make the sled fixture it is the brains of, and then all that is required is any kind of table saw and one of the .023” kerf blades sold by either Stew-Mac or LMI.

The device cuts any scale length between 24 3/16” and 26 1/2” with high accuracy and complete repeatability. It can be recalibrated infinitely within the ballpark to any of these lengths in less that a minute, and takes me less than 2 minutes to slot the fingerboard.

When I was hand cutting my fingerboards I had nothing like this accuracy (neither do you) and careful layout plus cutting was at least an hours work. LMI’s system works well, I’m told, but requires a new template for each of its limited number of scale lengths.

This idea is something new, yet simple, and people have always been slow on the uptake with this kind of thing, sadly. I laugh every time I use it.
Who sells the device, Bruce?
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  #34  
Old 02-17-2019, 10:27 AM
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Quote:
Originally Posted by Howard Klepper View Post
Digital calipers, as with many other devices that have digital readouts, create an illusion of accuracy by reading to more decimal places than the device is capable of resolving. Their rack and pinion mechanism introduces multiple sources of error--the slop in how the rack and pinion are cut, slop in the pinion bearing, and slop in how the rack and pinion engage. And that is all before the pinion rotation gets translated from analog to digital.

None of those issues exist with a simple vernier caliper. I can't understand those who think they are hard to read (especially if they think they can build a guitar!).

If you are locating frets by measuring and marking, you cannot get any more accurate than using a good rule (Starrett, Mitutoyo, etc.) marked in 1/100ths, a knife, and mildly magnifying glasses if you don't have perfect vision. Cheap rules are often shockingly far off.
My point exactly! My paper pattern is that level of accuracy.

Quote:
Originally Posted by MC5C View Post
As noted, frets don't really have to be all that accurate. They are cut into wood, after all, and wood just isn't particularly stable. Then they get filed on, crowned and polished. Then they go out into the real world of humidity and heat.

One of the biggest upgrades you can make if you are doing fretboards old-school is use an extremely sharp marking knife to make your marks. Old-school cabinet making and marquetry tool, a marking knife is sharpened with only one bevel, the other side is completely flat to the edge, and you reference your square with the flat side of the blade.
If you are cutting the fret slots by hand, it's hard to get more accurate than this. The use of jigs and power tools allows another level of accuracy, but I believe it takes a very perceptive ears to hear the difference.
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  #35  
Old 02-18-2019, 09:26 AM
Quickstep192 Quickstep192 is offline
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Thanks everyone for the advice.

I ended up making a drawing of the fret position in AutoCAD and printing it. I measured the fret locations with an accurate ruler to see if the measurements lined up and it was spot on. I then taped the paper to the fretboard blank and marked each location with an x-acto knife. The knife cuts seemed accurate and provided a slot of sorts to get the saw started in.

Then the trouble started. After getting the saw started, it would bind, making it very difficult to saw to the correct depth. Also, sometimes the saw would jump out of the slot, leaving a nice scar next to the slot. Easy enough to fix with some sanding dust, a fret dam and some CA, but still a pain.

Any suggestions on what I was doing wrong? The fret saw (StewMac) is relatively new. The teeth seem sharp although they have virtually no set which I’m guessing is what’s contributing to the saw binding in the slot.

Any suggestions?
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  #36  
Old 02-18-2019, 10:03 AM
tadol tadol is offline
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In general, handsaws bind from either being dull, or being pushed or driven too hard. Set should not be an issue with the shallow slots you are cutting -
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  #37  
Old 02-18-2019, 11:17 AM
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Marking is the easy part of cutting fretslots by hand. I suspect that the binding is caused by a little side force on the saw as you're cutting, it takes some practice to avoid it. The StewMac Japanese saw has no set, and is much easier for me to use than their regular fretsaw.
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  #38  
Old 02-18-2019, 03:05 PM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by Quickstep192 View Post
Any suggestions?
Maybe.

Are you using a Western push saw or a Japanese pull saw? (Sounds like Western.) Can you point out the saw you are using on their site?

Is the fingerboard already radiused across its top? It is easier to cut a flat fingerboard. Have you already cut the tapered profile of the fingerboard, or is it still a rectangular blank? It can be easier to cut while still rectangular.

Are you using any guide, such as a square, for the saw to ride against? That can be helpful in keeping the saw where it should go.

A little wax on the sides of the saw blade can help with the saw binding in the slot.

If the saw is sharp, it should largely cut under its own weight.


A technique for marking anything, that I was taught many years ago, works very well. Apply masking tape to the surface to be marked. Then slice through the tape with a sharp knife while marking shapes or positions. In the case of closed shapes, removing the interior shape of tape provides a border left by the remaining tape. The border defines the "keep-in" area. For individual making lines, the cut in the tape provides a physical edge to reference and an easy to see visual marking.
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  #39  
Old 02-18-2019, 05:48 PM
Quickstep192 Quickstep192 is offline
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The saw is this one from StewMac:

https://www.stewmac.com/Luthier_Tool...SAAEgIOKvD_BwE

The board is still square (rectangular) and flat across the top. I had no trouble getting the saw blade to stay in the slots I cut with the knife; it only went askew when I had to push hard because it was binding. I did try wax at one point and I think it helped, but I thought having wax in the slots might not be the best idea.

By the way, the wood is curly maple in case that matters.
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  #40  
Old 02-18-2019, 09:55 PM
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Those are usually called dovetail saws - they are designed to cut with the grain like a rip saw, but they may be getting these toothed differently for their application. Are you using a fixture, or clamping the fretboard down? Maybe you should clamp a small block onto the fretboard and let the saw ride against that to keep it straight - Also, are you taking long strokes? The space between the teeth (gullets) is what carries the sawdust away - with a very fine toothed saw, the gullets load almost immediately, so they will actually prevent the saw from cutting until they clear the edge of the board and can dump their load - if you push harder, then you force the saw to bend slightly and that can cause it to bind. Thats why you try to take long strokes and let the weight of the saw do the cutting and never force it. Its also why it is critically important to keep the saw very sharp -
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Last edited by tadol; 02-18-2019 at 10:01 PM.
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  #41  
Old 02-18-2019, 10:47 PM
charles Tauber charles Tauber is offline
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Quote:
Originally Posted by tadol View Post
Those are usually called dovetail saws - they are designed to cut with the grain like a rip saw, but they may be getting these toothed differently for their application.
Actually, they are called "back saws" in reference to the rigid spine across the top of their blades. A backsaw can have either rip or crosscut teeth. (Ripping is cutting along the grain, crosscutting is cutting across the grain.) A subset of backsaws are dovetail saws. Many dovetail saws have crosscut teeth, though the better ones have rip teeth.

The stewmac saw states that it has custom pull-cut teeth. I have that saw, but have never used it. I just took it out now and it does, indeed have pull-cut teeth and cuts on the pull, not the push. Mine cuts adequately, probably no better or worse than my older fret saws with standard push-cut teeth. It doesn't cut as well as my better (more expensive) dovetail saws, but they have a bigger set on the teeth.


It might be that in use, Quickstep, you are powering the push stroke, rather than the pull portion of the stroke. That might lead to it binding and skipping in the kerf. In 10 minutes, you could make yourself a simple bench hook or 90 degree "mitre" box that would eliminate the ability of the saw to skip and score the surface of the fingerboard.
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  #42  
Old 02-19-2019, 12:07 AM
tadol tadol is offline
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Well, actually, a back saw is any saw with a spine or back on it - the normal expectation when the handle us mounted in line like that is to call it a dovetail saw, but those are also made with open handles, while most back saws have closed grips like carpenters saws and use a crosscut style tooth, as when used in a mitre box - for dovetailing, they use a rip style tooth almost exclusively. As these saws have become far more generic in trade and use, they are now most commonly found with crosscut teeth and even with offset handles to be used for flush cutting. Much of this is to create a cheaper saw, which uses less steel, and with the assumption that it will never be re-sharpened, so they frequently use steels that are more rust-resistant rather than steels that sharpen well. And all that ignores traditional japanese saw technology, with a very different approach to the steel, and the tooth design, and the use of - which has also changed radically, with mass production, the introduction of disposable blades, and introduction into western woodworking and western marketing -

Sorry to be pedantic, but I owned and worked in a couple of shops that specialized in fine and antique woodworking tools when I was younger, and spent a very great deal of time with hand woodworking tools and teaching hand woodworking techniques and collecting antique tools -

I do believe the OPs problem is one of technique, primarily -
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  #43  
Old 02-19-2019, 06:18 AM
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All saws used to be rip saws before the invention of crosscut teeth. Rip teeth look like a line of little chisels that scoop out the wood while cross-cut teeth look like a line of little knives that cut the grain you are sawing across. Either type pf teeth will work fine in the shallow cuts we are making for frets or even dovetails that are less than 3/4" deep or so, although a good rip saw is a joy to use for longer cuts. The "back" on the back saw is to allow the use of a thinner saw plate to allow for thinner kerfs removing less wood making for easier cutting, although I have cut dovetails with a 26" 11 ppi cross cut saw to see how it went and it went just fine. I agree that it sounds like a matter of practice and technique, as either type of tooth in almost any size should make short work of those shallow fret cuts.

Ed
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  #44  
Old 02-19-2019, 09:53 AM
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When I used to cut my slots by hand I had all the same problems described by quickstep. I developed 3 solutions. Foremost is practice/practice/practice, all new skill sets require practice. More practically, lubricate the saw with something like saliva; seawater or a very mild soapy water solution might work as well. And third, clamp a well machined piece of 4/4 hardwood exactly on the line to be sawn, with a waxed surface and hold the saw hard against the 4/4 face with one hand while driving the handsaw with the other. This VERY simple fixture eliminates most of the trouble. . . . And requires some more practice.

The even simpler device I replaced it with (not counting the table saw component) is a total no brainer. If one were doing only a single fingerboard, hand sawing might be slightly less time than making the required fixture and slotting the board, but two fingerboards would already be more time efficient. And it only gets better.

runamuck . . .you’re kidding me? Look at Ben Wilborn’s Warhorse build thread for pictures of the Corian component of the MultiScale fixture he recently built. The white part is what we’re talking about. Same component, different application. I’ll poke around in my file system for photos of my application for the same component and put them up here later today.
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  #45  
Old 02-19-2019, 11:00 AM
charles Tauber charles Tauber is offline
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To further Bruce's suggestion...

A while back, Lee Valley created a saw guide that has embedded magnets to adhere to a saw blade covered with a thin piece of teflon, to allows the saw to slide against the magnets easily:

http://www.leevalley.com/en/Wood/pag...18&cat=1,42884

You could easily rig up something similar to a hardwood block, as Bruce suggested, but with the addition of drilling a few holes for embedded magnets and putting a veneer of teflon over it. That would keep the saw cut square across the board, square to the surface of the board - a potential difficulty with un-aided hand sawing - and prevent the saw from wandering out of the kerf.
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