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Romanillos' heel slot uses double wedges:



I’d like to try this. Can someone who uses a double wedge in the slots a la Romanillos share some specifics that work for you: optimal slot width and how you cut your slots (particularly if you use hand tools for this), wedge dimensions, any recommendations for making the wedges, fitting and glue up. Thanks.

Joe

I use a single wedge but a double wedge is supposed to be a little easier to fit. I just knife mark it all and then pare off a touch on the waste portion, up to the knife marks. It creates sort of a little groove for the hand saw to sit in. I just then saw by eye. You can go off a little because the wide slot allows you to make adjustments later on, you can get both sides symmetrical. For the width I use 5 mm's soundboard side, 10 mm's for the Back. I would probably add on a extra 2 mm to these measurements for the double wedge. The exact dimensions probably aren't that important. What is more important is that the 4 inside surfaces of the slot are flat and true - that makes fitting the wedges so much easier. You can get to them with a chisel and a flat file.
With the wedges I just cut them well oversize and plane them to fit, testing them regularly. If you mess up here you can always make fresh ones. Actually if you can accurately cut two slots at 2 mm's (old style) I'd be tempted to use that method. I think it's a lot quicker.

Thanks Michael. Your comments are very helpful. How does this look for the double wedge:



So the slot width would be about 12mm.

Joe

Oh I'm sure that would work. The one thing I forgot to mention is the issue of glue - or not. I don't glue them in but many (perhaps the vast majority) makers do. I think either way is fine. I haven't had any problems not gluing them. Once the soundboard and Back is on, they aren't going anywhere. I do like to wet the end grain of the wedges though. That raises the grain, I sand it flush again before gluing the Back. You don't want that end grain swelling and causing a slight gap between the Back and the slipper heel. It's just a precaution.

Thanks again Michael. Good point about the end grain potentially swelling and also not gluing. Romanillos explains (link below) that one of the reasons for going to the wedged slot and no glue was to minimize damage to the guitar sides if the guitar ever needed repairs to that area, as apparently happened to several of his early guitars:

http://www.youtube.com/watch?v=5Z51O6yn1m8


Joe

I was taught to use a single wedge in a wedge-shaped slot, but found it tricky to get good pressure over the length of the wedge. I switched to a 2-wedge method, and then heard later that this technique is attributed to Romanillos.

I don't think the width of the slot is critical, 10-12mm works, but I take care to make the shoulders of the slot parallel. I cross cut mine on a table saw. Robbie O'Brien has a Tips du Jour showing this http://www.youtube.com/watch?v=KXMhE2cIE_g. I simply use 2 spacer blocks of different thickness to make 2 parallel cuts.

I then prepare a wide SINGLE wide wedge that has the right dimensions, THEN rip it in half, giving me two wedges that when fitted have parallel surfaces to push against the slot shoulders -- it's much more difficult to achieve this making the 2 wedges separately. With or without glue, this gives you a joint with a tight fit of the side against the full height of the heel shoulder. I usually use the offcut from the neck when I rip the back surface to tapered thickness on the bandsaw -- the taper of the offcut is almost exactly what you need for wedges. Cleanup the cut surface on a belt sander, and you're left with a wedge 75 mm wide that provides material for all 4 wedges. The pointy end of my wedges is usually 1-2 mm, but again, it's not critical.

A pack of shims from the local home despot will probably give you a lifetimes worth of tapered wedges.
Making a single long wedge and cutting it in half would also give you matching tapers - one thicker than the other.
Does using "nonglued" wedges really save the sides from cracking from a fall that is hard enough to snap a neck?

It's a bit overkill. It would be easier to glue in a couple of side abutments next to the heel slot.
BTW the single wedge is a very old method, dating back to baroque Guitars.

Or a batch of cedar shakes.

I can't figure out what is implied by the repair question - I can't imagine that there is any impact on tendency for sides to split, and in the event of a neck reset by slipping the heel, it doesn't really matter if the sides are glued in or not. I'm confused over this one.

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Jim Kirby
kirby@udel.edu

Thanks everyone for the responses.

I don’t have a table saw so I think I’ll have to rely on the traditional handsaw method, perhaps tailored slightly as described by Michael N. Also, it looks like the table saw produces a straight, constant width web along the centerline between the slots rather than the traditional tapered web, i.e. getting wider toward the soundboard. Wouldn’t the additional material left intact for the web make a stronger, more solid heel?

The wedges only took a few minutes to make and were fairly easy. I used a slightly different cut off from the neck blank than Tim but still made them in matching pairs. They came out with a uniform 8mm width when mated, which should nicely fit a slot width of 10mm +/-.

Since the process was precise and fairly easy, I’m posting some pictures and describe for anyone interested. Starting with a stick about 15mm x 10mm and 35” long, the wedge angle is marked at one end. The stick being long was safely freehanded through the bandsaw to cut the wedge shapes. The two halves were then placed side by side, sliding them against each other to match the ramps, stuck to the end of a flat board using double stick tape, and leveled with a few passes of a hand plane.



Joe

I agree about keeping the tapered web, which would require some sort of jig to tilt the neck blank while using the table saw. I've cut all my slots for non-wedge Spanish heels by hand, and keep a much heftier width of material at the fretboard end. But the jig to tilt the blank shouldn't be that hard.

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Jim Kirby
kirby@udel.edu

You may want to pm David Laplante from this site.
He has studied with Romanillos.
Mc

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Mike Collins

When I attended the Romanillos course at Siguenza, Jose showed us a saw that he used to cut the slot, which consisted of two blades 10mm apart separated by a block so that the full width of the slot could be cut in one go and then chiselled out. I use this joint now but cut the two edges of the slot separately with a stiff tenon saw and chisel the slot out. I cut a wedge four times the width needed and cut into four. The wedges are glued to each other and the neck but NOT to the sides. I don't build in the Romanillos method but attach the sides to the neck with the wedges before attaching the top.

Colin

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I don't believe in anything, I simply make use of a set of reasonable working hypotheses.

Thanks Colin, exactly the info I was looking for.

Joe