Questions and Answers
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Q: QUOTE (Dru Lee Parsec @ May 26 2004, 11:59 PM)
Is there a benefit to joining the headstock one way
or the other, 
or are there side effects to joing the headstock the 2nd way that I'm not considering? |
A: The way I do it is far more universal (first diagram) than the "under the fingerboard" scheme. I guess you could make a case for the alternative (second diagram), but the traditional scheme doesn't fail unless done incompetently. The alternate can also fail if done incompetently. In fact in some circles the alternate is used as a scheme to graft in a new headstock on a guitar whose original has been destroyed. Indeed, I was called on to repair such a repair once: the fingerboard had flexed slightly, and the scarf underneath had popped! Another downside of the scarf under the fingerboard is that it is very obvious: I hide my scarf seam completely under a small crease sculpted into the back of the headstock. |
| Q: QUOTE (marcus @ May 27 2004, 12:51 AM) Mr Cumpiano do you still use titebond for this and other guitar construction? I do, but I'm leaning towards hide glue. | A: Yes, I use strictly TiteBond or Elmer's Carpenter's Glue, both Aliphatic Resin evaporative glues. I shun hide glues because it makes a sticky mess, although there are good reasons to use hide glue (higher heat resistance than TiteBond) and reasons not to use it (lower moisture resistance than TiteBond). Use what you're best accustomed to. They both make good guitars. |
| Q: QUOTE (west coast dan @ Jun 3 2004, 03:36 PM) Great jointer! Do you prefer this to a power jointer because the joint is smoother (without the fine ridges so common with the standard jointer)? Do you use a "spring joint" or just go for perfectly straight cuts? | A: The knives on power jointers not only leave minute ridges, but also compress the soft tissue on top of every ridge, particularly if the knives aren't razor sharp. So the tissue swells up where it has been compressed when the glue is applied. So I usually power-joint the edge to get it into the ballpark, and follow with the hand plane until fresh seam is exposed. An interesting anecdote. I interviewed C.F. Martin III during the early eighties. He was in his eighties at the time, and had been drawn out of retirement because his family's company had come upon hard times. He was shocked to find that on the factory floor, soundboard seams were being power jointed prior to glue up. He commanded that the practice stop and the old way of hand planing be put back on line. I don't know if the practice reverted back after he died. |
| Q: QUOTE (Wilfred @ Jun 5 2004, 02:43 PM) I see you have a great amount of kerfed linings there. Are you aware of an easy way to mass produce it by hand and if so could you share. | A: No easy way, sorry. I wish!! Very tedious, laborious. So I reserve two days out of the year, and make a year's supply. My system doesn't make it easier, it just makes them come out more accurate and more flexible. It's far easier to show than to describe, so I'm afraid it will have to wait until the next time I actually do it. I'll photograph the sequence and post it. |
| Q: QUOTE (deane @ June 15, 2004 11:58 AM) I loved the wide belt sander you designed and use in your shop. I have toyed with the idea of making one myself. Can you supply any design details? (Helicopter bearings?) I am really curious about how you raise or lower the work, and control in-feed. | A: I'm afraid it's too much typing to supply design details and I'm just too lazy. But there's a better way: Fine Woodworking magazine did a feature article on this very machine, with photographs and diagrams. Unfortunately it was published eighteen years ago and is out of print. You can find it in a library, perhaps: it's issue #58, titled SHOPBUILT THICKNESS SANDER A low-cost alternative to handplaning" |
| Q: QUOTE (minigo @ Jun 17 2004, 11:53 PM) Hello again Mr. Cumpiano this is James writing back to you I just want to thank you for all those pitures and giving people a chance to see real master builder at work. Your tips on doing things and your shooting board ,was awsome. Im going to try and build me one of those ,but right now I'm previously working on my Moms garage roof replacing both the roof and the wood at the rakes and ,soffit and ,etc. Im not much on doing all those things ,so ive encountered a sure head -ache for sure. Im still hoping to get in some tipe of training for luthiers and maybe some day I will be able to attent your tutural sessions there. Theres so many things about ,for instance how you configure the arching of the upper transverse brace ,the one you talked about in the koa build ,where you figure the scale length along with the upper bout width I think it was? Im having a real hard time on that situation because even though I have your book I m still confused about those configurations,because you stated in the koa build that was a very crucial configuration,if you have any info ,on that I would deeply appreciate it , and one more thing ,that as a reallynice looking guitar you built in the koa build and the bracing I also noticed was different from any Ive seen before ,thanks a million William on giving people your ingenious insight on the art of luthery. | A: Thanks for your message and your kind words. People don't realize that I wrote the book over 15 years ago, that is, half a career ago. Since then I've moved on... as would be expected. The headblock fixture in the forum sequence is a refinement of what is illustrated in the book. ...As is my barrel bolt neck joint, which I originally devised to simplify the build process for my students, and then wondered why I was holding on to the cumbersome pinned mortise and tenon system I had learned from my teachers. It's great now to be able to string up the instrument in the white, and do 5-minute neck resets until all the neck/body geometry is correct under actual tension--instead of having to account for tension as I did before with the pinned tenon system. So I haven't pinned a neck for 6 years or so. You noticed also that in these 15 years I've also simplified the soundboard bracing pattern over the years, as the photographs in the sequence show. I realized over the years that the extra braces were structurally unnecessary, and the simplification seemed to contribute to the idealized kind of sound in my head that I was trying to achieve--without a structural downside. |
| Q: QUOTE (Wilfred @ Aug 2 2004, 10:52 PM) I was wondering when fretting with the hammer could you describe the bend on the frets, the number, order, and position of strikes which it takes to get the fret seated comfortably. I have a problem with fret ends sticking up and repeated blows just make matters worse. I have resorted to gluing the ends and clamping. | A: I'm using (and loving) the Stew-Mac fret bender, that allows me to accurately curve the fretwire to a bit tighter curve than the fingerboard surface. This puts a natural down-pressure on the fret ends. I tap from left to right across the frets, holding the ends down with my fingers as I tap, which muffles the vibration of the wire and help keeps them from spronging up behind my hammer. For this all to work by the way, it is imperative to have a good match between the fret slot kerf and the tang width. The slot should be wider than the tang but narrower than the distance between the barbs. A .025 slot works well with most Stew-Mac medium fretwire. I insert the frets from 1 to 20, and don't jump around as Sloane recommended. Oh, and I put a thin bead of white glue under the tang before fretting. Hopefully it will slide the fret in easier, glue back together the wood fibers damaged by the penetration of the studs (barbs?), and fills with hard stuff the clearance void in the slot that remains under the fret. I would prefer to use cyanoacrylate, if only I could dispense the appropriate amount consistently without the trouble of cleaning off the splatter on the fingerboard surface afterwards |
| Q: QUOTE (slstexas @ Aug 2 2004, 10:53 PM) I do have a couple of questions: Did you use rosewood [brazillian ? or Honduran?] for this bridge for color coordination - or - some other reason? Do you put inlay work in fingerboards? If so - when would you do this in the sequence? When you apply a pick guard, when do you do it and what materials are you currently favoring? I really have enjoyed your pictures and commentary. Thank you for sharing this. | A: I prefer Brazillian bridges because I'm well-stocked and I like the appearance. My training is from a school of thought that resists fingerboard decoration unless a gun is held to my head. The guitar is a tool for good musicians, and most find the decorations distracting. Side dots suffice to orient your hand. I usually steer customers who want Victorian gingerbread all over their fingerboards to other builders. Those customers usually end up being insufferable, self-involved, annoying project managers anyway, so I send them away with no regrets. I prefer building tools for serious guitarists. And these usually prefer a clean, blank fingerboard. I either choose clear peel and stick acetate or tortoisoid acetate for pickguards, and apply them strictly on top of the lacquered, polished soundboard surface. |
| Q: QUOTE (tep5 @ Aug 7 2004, 02:06 PM) I was curious if you use slotted or unslotted bridge pins. And what is your reasoning. | A: If you read me commentary on bridge pins above, you'll see that I'm not personally convinced that the bridge pin has to tighten against the string, or viceversa. The string is bearing against the leading edge of the hole in the bridge, and is pretty much unmindful of whether there is a pin behind it. I've seen bridge pins fall out of some guitars while the string was under tension. But that's a pretty precarious situation because all that has to happen is for the ball end to pop out of the hole for mayhem to ensue. But that's why the bridge pin is there, and to my mind, the ONLY function of the bridge pin: to stop up the hole to keep the ball end from finding it's way out of the hole. All it is not much more than a fancy hole plug. If you've ever seen a bridge pin shot out of a guitar, you would realize what can happen when the bridge pin is wedged in against the string--while the ball end hasn't quite seated against the bridge patch. The string slides up the hole abruptly coming to a stop when the ball end comes to a stop against the bridge patch... ejecting the wedged-in bridge pin across the room. So it doesn't matter whether you use pre-slotted bridge pins or unslotted bridge pins. In either case, you still have to make a clearance notch of the proper size (deeper in the case of unslotted pins) to insure that the string does wedge up against the bridge pin. Hope that exhausts that topic. Some people obsess about the subject endlessly, like 13th century theologians arguing over how many angels fit on the head of a pin (a bridge pin, maybe?)--as if by arguing ad infinitum, somehow the truth will emerge. |
| Q: QUOTE (Wade @ Aug 11 2004, 03:30 PM) One question, when you are ready to finish a guitar, how do you remove a half glued bridge without damaging the top? Any special tools? | A: I used Elmer's White Glue for the half-bridge gluing. It releases cleanly at 130 degrees F. By the way, save for the danger of some goofball baking their guitar in a car, I would be confident in constructing the entire guitar out of Elmer's: it is considered an extremely high-grade glue in the adhesives industry, even if it is used in Kindergarten to glue paper cups together (it is non-toxic). I warm the bridge with a small traveling iron, after surrounding it with a corrugated cardboard "mask" (several layers of 1/8" corrugated box cardboard add up to the height of the bridge, and make an excellent heat-sink) and paddle the thing off cleanly with a wide spackling spatula that's had its edges rounded over. Stew Mac also sells a plug in bridge heating pad which works well. Both iron and pad can cook your bridge if you fall asleep at the switch. But don't take this as an endorsement for Stew Mac. I'm mad at them for trying to sell me 6 tuning machine grommets for $8.00. Oh, if you buy 1000, they'll give you a break: $7.99 |