Official Luthiers Forum!

So far I have always bought my fretboards pre-slotted and pre-radiused, with the new CITES rules for rosewood and the poor Canadian dollar I'm thinking of investing in a fretboard slotting set up.

The saws primary function will we fretboard slotting. What is a good table saw to buy for this operation?

I have both a Bosch an a dewalt little contractor saws, both are adequate for the task. The dewalt was just north of 300...

First I will offer an answer, but then a suggestion.

You need a table saw with a 5/8" arbor, and one that will allow the adjustments that make the blade perfectly parallel to the miter slots. You have to buy a special blade of the proper size, which costs a minimum of $100 USD. Any compact table top contractor-type saw of a decent quality will do, but the adjustment thing I mentioned before is critical.

Now the suggestion: I would not buy a table saw for just this operation, because there is a hand tool way of doing this. I use my table saw for lots of other things (guitar building and otherwise), so it earns its keep, but if you will only use it for this, I think you don't need one. If I were you, I would either get the proper sized handsaw for this or think more expansively about what you can use a table saw for, and then get a decent one. Not huge, but decent. Mine is a hybrid saw, and it is perfect for what I need.

As Don said, most any saw that you can adjust the blade parallel to the miter slots should do it. You will also want the space between the slots fairly wide so your sled will be stable.

Actually I'm not so sure any small saw allows you to adjust the blade to the miter slots, just the fence to the blade.

I'm not big on hand sawing so either using the main saw (that's how I do it because of space limits) or a secondary saw (sounds like a sweet deal to me) works.

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Joe Beaver
Maker of Sawdust

Anything with a tightly spec'd table with two slots to run the sled along I would think. I just set up my super old Craftsman and it does a fine job. I actually prefer that saw to the new saws that I see at Home Depot/Lowe's as it has a cast iron table and just feels more rigid. You can probably find something similar used for $100 or so on CL that will work just as well as anything new. Just be sure the 90 degree angle can be adjusted as someone else mentioned earlier.

I've been using my Jet contractor's table saw to saw frets slots for years. You don't need that expensive blade, I use small slotting (slitting) blades made for machinists which cost around $15. You'll need a sleeve to put over the 5/8 arbor of the table saw to accommodate the 1" hole in the slotting blades. Any machinist can knock out a sleeve for you in minutes. The table saw works so much better than hand sawing, the frets slots come out uniform with square bottoms and the operation takes minutes. I usually do 3-4 fret boards at a time since set-up takes more time than the actual sawing.

We (KMG) have a dedicated Delta Shop Master 10" set up for slotting. Our full width sled uses both the left and right miter slots for nice smooth travel. We tried machinist slit cutting saws, as well as LMII and Stew Mac fret slotting blades. The Stew Mac blade is far superior to the others and is highly recommended. I use one standard blade stabilizer/stiffener. I would add that the over priced stabilizers offered by the luthier suppliers are just that.

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Ken Cierp

http://www.kennethmichaelguitars.com/

I made a simple tablesaw using a direct drive saw motor and some scrap material. It uses a 3" blade from a Makita battery saw. Very crude and loud (motor) but it works well. It wouldn't be hard to mount one of those blades to a mandrel and build a table around it. On my saw the table raises on one end using screws and spacers to set the depth of cut. Since the depth of cut doesn't vary too much or too often it works fine. The saw can also be used to cut purflings and bindings.

I don't believe the adjustment to make the blade parallel to the miter slots is important for this crosscutting operation - for ripping it is, but not for this. If the blade is out of parallel a bit the end result will be a sightly wider slot, but only by a tiny amount.

Ed

If the miter slot isn't parallel to the blade, no amount of adjusting your slotting jig will get you a 90* slot that isn't wider on one side of the FB than the other. You can work around this by filling the slot, usually 3/4" wide with hardwood, and making a narrower and shallower slot parallel to the blade.

Alex

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"Indecision is the key to flexibility" .... Bumper sticker

We use a well adjusted (happy? healthy?) cabinet saw with the Stewart MacDonald blade, a single stabilizer plate on the nut side of the arbor, and a combination fret slotting and kerfed lining sled for the job. All of our templates are made from standard 2" x 1/8" x 48" aluminum 'yard stick' stock and milled using a printed template made with a PC program available from the Musical Instrument Maker's Forum (MIMF) archives called WFRET. Other than the blade and the saw itself, everything else is shop-made and quite inexpensive. Milling our own templates allows us to custom-make both new and replacement fretboards in any feasible scale length, and to match oddball scale lengths such as that found on 1930's Martin OM guitars.

In reading the thread, there seems to be some lack of alignment of thinking in the discussion on the effect of blade and miter slot misalignment, to which I respectfully offer the following comments:

During my time with HFH, I've milled out coved moldings and relieved the back of commercially made trim and moldings to fit masonry using a tablesaw with an angled fence, which is why I agree with Mr. Minch's contention that - should the blade be out of parallel to the slots - the net result is a slot of consistent width, but one which is narrower at the bottom of the slot than at the fretboard surface...which is to say a section of an ellipse is milled for the small angles of misalignment we might see.

It also seems to me that a lack of parallelism between the blade and slots will not influence the angle made by the milled fret slot across the fretboard, but will (as mentioned) affect the shape and width of that milled slot as above. As long as the sled is set at 90 degrees to the table slots, the fret slots will also be at 90 degrees to the chosen centerline (or milled edge) of the fretboard blank.

On tablesaws in general, it seems as though the luthiers I have met either eschew thier use in favor of other stationary or portable power tools, or use them as core stationary tools. As a cabinetmaker, boatbuilder, aircraft fabricator, and carpenter, my boss hews more to the later, using it to rip out bindings and purflings, lining blanks, and bracing stock, and - with various jigs and fixtures - radiusing bracing, rough-profiling rims, milling truss rod slots, and fabricating all those jigs, fixtures, and shop furniture that are so handy in a commercial build/repair shop.

All of which has me checking the regional Craigslist boards to find a steal on a saw for my own dream shop. CL sees frequent listings for almost new and lightly used tablesaws in the $200-$450 range for contractor's saws (there are two 'New In Box' Ridgid cast iron top 'pro' contractor's saws at $460 asking in the DC CL today, plus a range of Sears and other brands for less) and $600 and up for hybrid and cabinet saws. All three options feature straight-forward blade and miter slot parallelism adjustments, as well as lots of aftermarket motor, fence, and safety options for older tools.

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A constellation only takes shape when one maps the whole.
- Beth Brower

I picked up an old DeWalt (a real one, made in PA) for $130 that I use as a dedicated fret slotting saw.

If you can find a little one, they're usually in great shape because they were sold for hobbiest but built like true industrial machines.

It's the little guy on the left

Kevin Looker

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

Excellent post by Willard above, and I only add one thing to the following part of it:

"[T]he net result is a slot of consistent width, but one which is narrower at the bottom of the slot than at the fretboard surface...which is to say a section of an ellipse is milled for the small angles of misalignment we might see."

The width of the kerf will be consistent across the fingerboard, but the fact that the mouth of the kerf will be wider than the bottom of the kerf might mean the mouth of the kerf is too wide for the installation of frets. We buy these blades with a specially ground width, and no set, in order to cut a very precise width of kerf. A wider kerf mouth makes it less likely that the fret tang barbs will have enough wood to grab onto. Maybe they will be OK, but maybe not. I would rather make sure my blade is parallel to the miter slot, so I can cut the size kerf the blade was specially designed to cut.

Me too! Having a hard time understanding intentionally setting up an operation any other way.

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Ken Cierp

http://www.kennethmichaelguitars.com/

No trouble with non parrallellness with either the Bosch or dewalt, using the lmi power slotting system.

My right brain was thinking exactly what Woodie so left brainly described. Like anything else, if it falls within our tolerance threshold or measuring capability (I'd say +2 thou) we're good. Just measured some evo and the barbs don't start until 20 thou depth.

Med, did you have any issues with that blade falling into the threads?

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Pat

Kevin, what size is the small one?

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Pat

It's a model MB, 9".

Here's a pic with the StewMac blade & my fence setup. There's an index pin which you can't see that engages with the StewMac templates.

Kevin Looker

_________________
I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

No, not at all. The power slotting system comes with two blade stiffeners that lands things on the smooth arbor.