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Anyone do binding/purfling routes like this, with a routing table, and an extension bearing for the side. Looks like the simplest, and easiest way I’ve seen. About 18 minutes in:

https://youtu.be/pEpACOTrUMo?si=85-Ayu7workPQB9T

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Why be normal?

Many makers these days use some variation on this method. The main things are to keep the axis of the cutting bit parallel to the side, and control the depth of the cut in in both directions. Some prefer to move the router, and others to move the guitar. Either way it sure beats doing the job by hand with a marking gauge, chisel, and file. OTOH, I like knowing how to do it the old way, too; sometimes you have to, and it's nice to know you can.

In function and structure, that’s very similar to the Elevate Luthier jig that I have been using the past couple of years. https://elevatelutherie.com/product/ult ... nding-jig/
I’ve done well over 100 guitars where I’ve cut the binding ledges freehand with bearing guided bit and a donut on the router base. I’ve tried the sliding jig with the router mounted on a base that rides up and down and the guitar is on a sliding base that keeps it level. I’ve gotten the best results with the Elevate jig and now use it exclusively. The table jig in the video operates similarly.

I did my guitars with chisels and markers. I don’t use a form so I was thinking; (always a dangerous thing) that if I have the blocks, back and belly glued together the ribs would be simple to glue on. I found that out gluing ribs on a cello. The inside form I made for that has 3 layers, consecutively bigger, and the smoothed into a plane. The cello is bigger on the top than the back; 3 to 7 degrees or so. The ribs were very easy to fit, and glue, even being tapered and curved in 2 directions. All I need to do for a guitar, is to glue spacers on the bent ribs to keep the top and back in the right place. It would just be gluing side reinforcements on before gluing the sides.

I could do a really simple binding just past the ends of the back and belly; and purfling would be simple; but the router table thing looks easy, and I could use it for routing for a truss rod too. It’s that, or the laminated neck with a center section the width of the truss rod. I don’t have a table saw.

Can you set a laminate trimmer to take a cut the thickness of binding. I know nothing about routers and trimmers. I have a little attachment for a Dremel that is useless. Even for a little binding cut. It works fine for cutting purfling grooves, and even freestyle fencing purfling. But isn’t good for any side forces.

I could do overhangs like Parker did; but glueing liners on with an anywhere near consistent overhang would be impossible. So a form would be needed. So it is make a form, or glue ribs on the outside of the plates. Making the belly and the back the same profile is simple.

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Why be normal?

Ken, the Dremel is just too flexible to do precision work. It’s okay for working up to line like when your cutting a hollow for inlay, but if you want to use it with a fence or a guide to cut a straight line, it can seriously disappoint you.

The table setup in the video could work very well for you.

If you build a router table, you want to make sure that there’s no way the router could drop out of its housing or out of the table when it’s running. Bad things can happen when a shaft with a cutter moving that fast is bouncing on the floor.

A router or laminate trimmer shouldn’t be asked to cut more than a quarter inch deep in one pass. Usually, more passes with lighter cuts are better than trying to do it all in one pass.

You’ve nothing to lose but a little bit of time if you get a laminate trimmer and start some experimenting on scrap wood. The cheaper ones often have more runout in the shaft than you want. I’ve been happy with the Ridgid, both corded and cordless, the Makita, and the Dewalt laminate trimmers (I set them up for different jobs and often leave them that way—that’s why I have so many.)

Rather than use the router table for truss rod slots, I cut mine with a fence on the router while the neck is still a plank before I carve it.

Enjoy.

KenNagy asked:
"Can you set a laminate trimmer to take a cut the thickness of binding."

Yes, either with some sort of 'finger' guide or a guide bearing on an over sized bit. Most folks user the latter these days, and places such as Stew-Mac offer sets of cutters and bearings. The main issue there is that the sizes of the rabbets you can make are limited by the guide bearings you have, so you either have to buy new ones to get more flexibility, or make your purfling and bindings to match the bearings you've got.

Finger guides, that ride below the bit and provide a depth stop, allow for a lot of flexibility, but at a cost. Mostly it's in the difficulty of ensuring a uniform depth of cut. If the end of the finger is radiused to a different diameter than it 'should' be the depth of cut will vary if you're not careful to keep the finger aligned to the radius of the bout as that point ('normal' to the curve). It sometimes doesn't take much drift to introduce problems.

Your 'cello with the non-parallel ribs is going to be a real challenge, no matter how you do it. I've never heard of one like that.

Alan, apparently Guadagnini did it, I thought it would be good. Then I saw that they thought Guadagnini made small cellos, so I drew up a longer, 750 long one. But it has a slimmer profile, while the Guadagnini is shorter and squat. The new Strad poster of an OLD Amati where the guy who plays it says the low E on the C string can shake the walls. That would be cool to do! The Guad viola I'm making has the same tapered sides, but since the ribs are so much shorter, it isn't as noticeable. I just glue the linings on both sides, and not the back. It is just a one piece form. The sides of the form ARE tapered, so the ribs lay right; and I have a form for the top and back to check where they are. I COULD make it so it could mount on the form.

I already did the cello. Bending the ribs was easy. The ribs are about 3-7 degrees or so. The belly is 750 long but the back is only 735. I have 2 pads in-between the 3 layers that are glue pads for the blocks. You HAVE to remember to take the screws out of the bottom layer from the bottom. The rest are from the top. You can have all the linings on, glue the back on, and then pull out all the layers. Then do whatever you want to do inside the ribs; and then glue the top on.

The cello was started, stopped, new back from slab Euro Sycamore (maple) because the original was too low after hacking sawing the wedge. I do things very differently now, although the inside of the belly is pretty much based on 2 diagonal centenary curves, so I'd like to make another, and more arch tops too. I tried cutting down the gloss, but the varnish is VERY tough. I thinned it with alcohol with resin in it. I had it too pink, I needed more green, but got too much red. Doing things in a hurry.

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Why be normal?