Tech: Instrument building questions

Subject: Tech: Instrument building questions
From: Cap't Bob
Date: 19 Feb 03 - 10:43 PM

Last fall A friend an I decided that we would build ourselves a uke or two for something to do this winter. I figured the first one would be filled with mistakes so local woods were used. The sides and back were birch and the top quarter sawn oak. The plans were purchased from Elderly (an early model martin design).

There were a few blunders like when I cut the angles for the tuners on the neck.   I made a jig because my saws were not able to handle the 15 degree cut. Subtracting the 15 from 90 I got 75 (wow). Then in great haste I went to 70 deg. and over another 5 setting the jig up for 65 instead of 75 deg. The 25 deg angle wasn't noticed until I had the neck all ready for assembling. I now have probably the only uke in existence with a 25 deg angle on the tuner section of the neck.

Question #1 - Is there some reason for the 15 degree angle? It seems that all stringed instruments, guitars, mandolins, uke's etc. use the 15 deg. angle where the tuners are placed on the neck.

Question #2 - Why doesn't oak make a good sound board? My first one sounds like it is muted.

Question #3 - I'm now on my third uke. Is building instruments addictive?

Cap't Bob

Subject: RE: Tech: Instrument building questions
From: John in Brisbane
Date: 20 Feb 03 - 12:25 AM

Q1 - My thoughts only. I've seen a luthier giving a workshop on re-srtinging a guitar. He was very particular about winding the minimum amount of wire onto the tuning shaft in order to maximise the angle between the shaft and the nut. Conversely (my guess) if the angle was (say) 80 degrees there would be better pressure at the nut, but the friction would make tuning difficult and the permanent bend would weaken the strings - hence the various convoluted knots that fisherpersons tie in their lines to avoid stress.

Q2 - I'll leave that to someone more knowledgable, but somewhere here lies a continuum between strength, density and the ability of the soundbard to vibrate sympathetically with enough volume and uniformity across the musical spectrum. Concrete is fantastic for speaker boxes if you don't want to move them and because the concrete does NOT vibrate sympathetically and hence colour the sound.

As an aside I knew a guy who bought a whole town's stock of street trees because the town was being re-located due to a mining project. He intended to use the timber for violin making. The trees in Australia grew much more prodigiously than their European equivalents and the timber was commensurately lighter (less dense)- and relatively useless for fiddle making. Fortunately he had an open fire - not typical of Australian houses these days.

Regards, John

Q3. - Addictions are just fine if you can effectively manage the outcomes. Is it an expensive addiction?

Regards, John

Subject: RE: Tech: Instrument building questions
From: Bee-dubya-ell
Date: 20 Feb 03 - 01:35 AM

The primary function of an angled headstock is to provide some down pressure so that the string stays seated firmly in the nut without buzzing. However, it is not absolutely necessary. Many electric guitars such as Fender Stratocasters and Telecasters have no headstock angle at all. On such guitars, the necessary down pressure is provided by string-trees, little T-shaped devices screwed to the headstock between the nut and the tuning machine through which the string is passed.

One reason for a 15 degree headstock angle as opposed to a steeper angle is that it is less likely to result in a broken off headstock. The shallower the cut, the more the grain continuity of the wood is preserved. A steep cut would expose more end grain and be more fragile than a shallow cut.

By the way, on some inexpensive guitars the headstock is made from a separate piece of wood which is glued onto the neck using a scarf joint. It's done primarilly to minimize waste, but some folks say that it's actually stronger construction than cutting the neck and headstock from a single piece of wood.

Also, the lute has a headstock angle much greater that 15 degrees. More like 90. They are also probably very prone being snapped off, but I'm sure most lute players treat their instruments with great care.

Bruce

Subject: RE: Tech: Instrument building questions
From: mooman
Date: 20 Feb 03 - 05:38 AM

In relation to question #2, oak has a greated density than typically used tonewoods and greater thickening and lignification (the process of laying down lignin in the fibres, vessels and other cells that makes wood "woody" as opposed to herbaceous plants). This makes it inherently stiffer than typical tonewoods with less freedom to vibrate, hence the muffled sound.

Having said that, it is perfectly possible to use hardwoods (as opposed to the coniferous "softwoods" like spruce, pine and cedar that are typically used as tonewoods) for the soundboard and there are many excellent-sounding instruments that use, for example, mahogany as a tonewood. In this case, top thickness will need to be reduced and bracing redesigned to allow the necessary flexibility and vibration of the top.

Hope this helps a bit.

Keep up the good work!

moo

Subject: RE: Tech: Instrument building questions
From: banjomad (inactive)
Date: 20 Feb 03 - 05:44 AM

Basically oak is too hard for a soundboard unless it is very very thin
which would weaken it too much.
Dave

Subject: RE: Tech: Instrument building questions
From: Mooh
Date: 20 Feb 03 - 09:15 AM

I've played some very nice hardwood topped instruments. Koa, maple, mahogany, cherry, even birch, and all have had their graces. Oak or ash for example on a small soundboard like an uke would need to be very thin to allow much vibration I would think, and as Dave mentioned would be quite weak.

The headstock angle question has been answered I guess, but I like to reinforce the face and sometimes the back of the headstock with an overlay of hardwood consistent with the woods of the rest of the instrument. With a minimum addition of weight considerably more strength is provided, end grain or runout is protected, and looks are improved. (A mandolin in progress on my bench has a four piece maple neck which won't even need a trussrod, but will get the overlay on front only for looks.) Consider a volute at the headstock angle for more support. Their value is sometimes disputed among builders but it can't hurt and looks cool to my eye.

As for addiction...the disease IS the cure!

Peace and sawdust. Mooh.

Subject: RE: Tech: Instrument building questions
From: Cap't Bob
Date: 20 Feb 03 - 10:33 AM

Thanks for all of the useful information and comments. I have been using a four piece neck and covering the scarf joint on the tuner section with an overlay. My thinking was that most likely the original necks were mostly made of one piece of wood and would be weaker if the angle were too steep between the neck and the tuners section. However, with the scarf joint I doubt that this will be much of a problem especially a the uke and not having too much string tension.

I discover that by tuning the uke to A, D, F#, B, rather than the normal G, C, E, A, the sound improved considerably. Guess that would put more pressure on the oak. Rather than doing a lot of experimenting I've sent away for some spruce for the next few ukes. I'm planning on building a uke for each of the grand kids that show any interest.

Hopefully I can keep the cost factor under control by using as much of my own wood as possible. Several years ago I cut some trees, had the wood kiln dried and its been seasoning for some time now. Mostly birch, maple, oak, walnut and aspen. Wonder if anyone has had experience with walnut? A friend gave me some mahogany from an old wooden boat that he is dismantling. A uke made from that would have quite a story to go with the music. The boat was even shipwrecked one time near Put In Bay on Lake Erie.

Mooh, after honeing my skills a bit on the uke's I would like to put together a flat top mandolin. That four piece neck is interesting and would probably be simpler than for me than using a thrussrod.

Cap't Bob

Subject: RE: Tech: Instrument building questions
From: JohnInKansas
Date: 20 Feb 03 - 11:08 AM

Cap't Bob

If you're near the water, I found that the boat repair yards in the Seattle area had a surprising amount of very nice scrap spruce at low prices. You won't likely find any "quarter sawn" but you may find some thick enough to cut thin pieces nearly across the grain (if you have a table or radial saw), and they are surprisingly easy to butt-glue into serviceable soundboard stock for something small like a uke. (Sort of like the "book-matched" boards the luthiers sell, but with several pages in the book.)

I made one lap dulcimer with this method that has really great sound.

Unfortunately, the second most common "nice" scrap you'll find is teak. It looks nice, and it's strong enough to take a lot of stress without breaking, but it "creeps" under continuous load, so I'd advise against using it for necks and such.

Remember that cutting thin slabs off a board, especially with an angled blade, requires strict attention to all the normal saw safety practices. Use your "anti-kickback" attachment if you have one; pressure board and push-sticks are also advised.

John

Subject: RE: Tech: Instrument building questions
From: Mooh
Date: 20 Feb 03 - 01:35 PM

Bob...For what it's worth, my Moon mandolin has a mahogany neck with a rosewood fingerboard and no trussrod. When I asked Jim Moon about this he replied that he didn't think a rod was required and might actually weaken the neck at that angle be removing too much wood. I think I agree. At any rate, it doesn't suffer from having no rod. I figure a maple neck (I intend to use an ebony fingerboard) needs a truss even less.

Peace, Mooh.

Subject: RE: Tech: Instrument building questions
From: Cap't Bob
Date: 20 Feb 03 - 03:53 PM

John

I've been working for some time now trying to figure the best method to use in cutting thin slabs from a board. The table saw was down right dangerous and I didn't even give the radial arm saw a try. The thing that worked best for me was my band saw. I broke down and bought one of the hi tech 3/4 inch wide blades (hi tech = any blade that will cost me over $30) designed especially for re-sawing. The secret seems to be going extremely slow with the cut and by doing this the blade doesn't tend to follow the grain.
        
Rough sanding is another story. I still haven't come up with a good way of getting the job done. It doesn't take much of an error to cut a portion of the wood too thin. The best method so far has been to tape the thin board to a larger board (using carpet tape) and then running it through the top portion of a 12 inch sanding disk. I have been looking at a small circular plainer that fits in a drill press. Sort of expensive little things and I'm not sure if they would be any better than the sander. I usually finish up using a scraper.

Mooh ~ I looked up the moon mandolin at hobglobin. It's a might nice looking instrument and similar to what I want to build. I play mostly celtic music on the fiddle and tenor banjo but would like switch over to the mandolin at times. I'm bothered a bit with carpal tunnel and find that changing instruments as often as possible seems to help.

I have red and sugar maple. Wonder what type of maple you are using. Around here sugar maple is usually referred to as hard maple and red maple as soft.

Cap't Bob

Subject: RE: Tech: Instrument building questions
From: mooman
Date: 20 Feb 03 - 07:50 PM

If you have the skill to fashion a multipart neck with suitable variation in the direction of the wood fibres, it is certainly feasible to dispense with the annoyance and added difficulty of accurately routing for a truss rod and have a perfectly stable neck.

I would concur with Mooh therefore.

Concerning thicknessing of the top, I always use scrapers rather than sanding.

Peace

moo

Subject: RE: Tech: Instrument building questions
From: JohnInKansas
Date: 20 Feb 03 - 09:24 PM

Capt B -

I've used my table saw, since that's all I had. If you've got a bandsaw, it's probably the best thing to use.

On a table saw, especially with thin cuts against the fence, there's a real hazard from kick-back, especially at the end of the cut when the cut-off thin strip can wedge against the blade. I've done some thin strips with the fence, without much trouble, using the anti-kickback "gripper", a fir-strip clamped down to hold the piece against the fence, a couple of sturdy hold-down sticks, and a slow and careful cut.

My prefered method for thin strips is to clamp (C-clamps over the edge of the table) two boards against each other to the table top, aligned with the tool groove. Slide the board against the one nearest the blade, so that the thin strip is "free" to drop off at the end.

For the second cut, loosen the board nearest the blade, use a spacer between it and the other board to move it by a fixed amount. Clamp that board, then move the other one up against it and clamp it. Make the second cut. Repeat as many times as needed.

You want your strips somewhat thicker than "finished" to allow for shaping and cleanup, so "thin" is probably at least 1/8 inch, and if you're doing an archtop, more like 1/2 or 5/8.

Clamp the strips face-to-face and sand the side of the stack to square them for butt gluing. Use an over-board to weight them flat, and put a good amount of clamping pressure on the joint until dry, and it should be stronger than the original wood.

For fairly large flat surfaces, I've had reasonably little difficulty smoothing them to thickness with a hand-held belt sander. The trick is to use a fine grit paper so the work goes slowly, be patient, and don't try to put a lot of pressure on it. If you're making a lot of "oops" cuts with the sander, use a finer (or older) piece of paper. Of course, the final work needs to be by hand, scraper, or more delicate tools. (I've always wanted a set of them fine finger planes.)

John

Subject: RE: Tech: Instrument building questions
From: Mooh
Date: 20 Feb 03 - 10:58 PM

Bob...Either maple will work well and I would choose based on figure rather than strength (as both are lots strong enough), or at least how well the parts will fit the available usable wood. The stuff I'm currently using came from a load of mixed rough lumber I acquired from a mill that went under some years ago, and I've had it stacked for several years. Be careful to avoid runout on any parts so that the wood doesn't splinter under your blades, scrapers, knives, or sandpaper.

Peace, Mooh.

Subject: RE: Tech: Instrument building questions
From: Bee-dubya-ell
Date: 21 Feb 03 - 03:32 AM

Capt Bob,

Some walnuts are excellent for instrument building. Claro, or California black walnut seems to be the most popular. Taylor, Breedlove and Wechter all build walnut-bodied guitars. I have a couple of friends who have excellent walnut guitars from small-shop luthiers. One of my guitars has a five-piece walnut neck.

Walnut would probably be a more popular wood for luthiery except that the price for the really good stuff has been bid out of sight by the custom gunstock industry.   

Bruce

Subject: RE: Tech: Instrument building questions
From: GUEST,JohnB
Date: 21 Feb 03 - 12:43 PM

I saw some really nice looking Hemlock a while ago which I thought looked good for a top. My memory even tells me that it was Quarter sawn. Unfortunately I did not buy it and have been cursing ever since. Anyone got any experience on using Hemlock for a top? It would fit the bill for cheap locally obtainable wood.
JohnB

Subject: RE: Tech: Instrument building questions
From: JohnInKansas
Date: 21 Feb 03 - 05:01 PM

The hemlock I've fondled around here is all a rather dense wood for a top, so it wouldn't be my first choice - unless it was a really pretty piece, of course. I have used it, because of the hardness, for small fittings, but the samples I've had access to would make better backs than tops. I haven't tried bending any.

It is listed in one of my refs as likely to produce health problems if handled too much, although not more so than quite a few other woods. It does raise the point that a dust filter should be used in many of the woodworking activities associated with instrument building. It's really depressing to find a wood you like, and then find you can't use it anymore because you've inhaled too much and become allergic to it.

John

Subject: RE: Tech: Instrument building questions
From: Cap't Bob
Date: 22 Feb 03 - 12:54 AM

I have one question about the 4 - 5 piece necks. I suppose that they are made of pecies around 3/8" thick laminated toegether. If this is the case are the laminates perpendicular or parallel to the fret board?   

I've been think of building a uke with the top easily removed in order to test some different woods for sound boards. The one I built with the oak sound board doesn't sound all that bad when tuned to the higher frequencyl.   

My latest uke (just finished it today) has a manogany top, birch sides and back and a maple neck. Looks and sounds great. Finally

Cap't Bob

Subject: RE: Tech: Instrument building questions
From: Mooh
Date: 22 Feb 03 - 01:20 PM

I generally laminate with the strips of wood running the length of the neck from the heel block to the tip of the headstock, and the strips at right angles to the fretboard. This takes advantage of the greater rigidity of the individual pieces versus the string tension, if you know what I mean. It's possible to hide a rigid piece of hardwood (or carbon fibre rod) in another wood for the neck if you prefer not to have the laminate look to the neck. I've never bothered to do this in my admitedly short building experience. From what I understand, for shorter neck and/or light tension instruments truss rods are not very necessary, so a non-adjustable reinforcement (even if it's just wood) is fine.

As for the look of laminates, properly glued they're sometimes not very obvious. I have a Beneteau guitar with a killer flame maple two piece neck and it looks fantastic, the glue line barely visible.

Hope this helps.

Mooh.

Subject: RE: Tech: Instrument building questions
From: Cattail
Date: 05 Aug 03 - 04:16 PM

Ressurecting this thread again, 'cos there's some great information in it, and because I would like to ask a question.

Can Mooh or anyone else tell me if there is anything against making
a solid neck, no truss rod, and bedding the frets directly into it?

Apart from the wastage if you get it wrong, I can't see why not.
Instruments must have been built like this before truss rods and
separate fingerboards were thought of.

I ask because I have an 1-1/4" thick piece of Honduras mahogany
left over from the transom of a boat I used to have, it's too good
to just make a coffee table out of and my thoughts are running
towards having a try at making an instrument.

Incidentally, are there no good uses for oak in an instrument?
as I may be able to get hold of some small, (and maybe not so small)offcuts of very good stuff.

thanks in advance for any replies.

Cheers for now.

Cattail 0~

Subject: RE: Tech: Instrument building questions
From: Murray MacLeod
Date: 05 Aug 03 - 04:50 PM

Well Cattail, there is a very good reason for making the neck and the fretboard from two different pieces of wood.

One of the main functions of the fingerboard is to resist wear from the abrasion of the strings, and historically, the timbers which do this best are ebony and rosewood. Those timbers are also the most expensive to purchase, and to use ebony or rosewood to construct a whole neck would be horrendously expensive, not to say a needless diminution of a valuable resource.

There is also the question of ease of working. The hard wearing qualities of ebony which makes it so suitable for fretboards renders it unsuitable for necks simply because it is so laborious to cut and shape, and is also murder on the tools. Honduras mahogany is a much easier and more suitable option.

That said, if anybody ever did make a one piece neck/fingerboard out of ebony, my guess would be that it would not require a truss-rod, and that it would never deform under normal string tension. Many of the best hand builders do actually construct their instruments without adjustable truss rods (as indeed Martin used to do) and if the instrument is built with close attention to tolerances, there is no need for an adjustable rod. There will, however always be a need for some kind of reinforcement in a guitar neck (unless of course it is made from solid ebony !!)

Murray

Subject: RE: Tech: Instrument building questions
From: Cattail
Date: 05 Aug 03 - 07:27 PM

Thanks for the swift reply Murray, I see what you mean about wear
on the fretboard, would any other wood than ebony or rosewood be
suitable for this?

I guess that what I'm trying to do is have a try at building some
type of instrument cheaply, using what bits I have lying around
instead of paying out for expensive woods, fittings etc.
(What a cheapskate, eh)?

I don't suppose whatever I build is either going to
look good, or play well, or sound very sweet, It would just be
nice to have a go, and maybe knock a tune out of whatever I end up
building.

I have read such a lot of good information and advice on here and
other sites that it's just stirred up the old creative juices again.

I do have a couple of books,

David Russell Young: The steel string guitar
Ronald Zachary Taylor: Making early stringed instruments

to help me, but for a first attempt would rather try to do it
without the expense of specialised woods, etc.

Once again, many thanks indeed for the reply.

Cattail 0~

Subject: RE: Tech: Instrument building questions
From: JohnInKansas
Date: 05 Aug 03 - 07:29 PM

An additional reason for the separate fretboard is that eventually frets do need to be replaced. Each time you pull out an old one and put a new one in, there is some "damage" to the slot, and eventually - if the instrument lasts for a few centuries - you'll reach a point where the slots don't hold the frets well, and the fingerboard should be replaced. A separate fingerboard makes it fairly easy, while an integral one would mean replacing the whole neck.

From a structural standpoint, cutting little slots in a part that is under load is theoretically a "baddy," since any "hole" with a sharp corner is what's called a "stress riser." Cracks have a tendency to "grow" from any sharp notch, and there's the remote possibility that fret slots in an integral fingerboard could be the starting point for eventual cracking of the neck. The smooth surface of the typical neck is at least theoretically a better structure, and the slots in the separate fingerboard aren't likely to grow because the fingerboard isn't supporting any significant part of the string load. It just lays there to keep the frents in place. Even if cracks spread from the fret slots in a separate fingerboard, they would usually stop when they hit the glue line between the neck and fingerboard.

This isn't saying that making the neck be the fingerboard is a "bad" idea, just that it suggests a certain extra small degree of conservatism in making the neck "stong" enough.

I haven't had enough ebony around to do much working with it, but I'm not sure that the assumption that it would make a "very strong" neck is warrented. Ebony is quite "hard," but it's main feature that makes it so good for fingerboards is that it's also quite "oily." It resists wear from the strings as much because of its built-in "slickiness" (the string can't dig in) as because of its hardness. (It is also quite dense, and would make a horridly heavy neck.)

The woods with high oil content generally may be quite "strong," in the sense of not breaking under a particular load, briefly applied; but they also tend to be somewhat "inelastic." Where another wood may bend under load, but springs back when the load is removed, the "oil woods" have a tendency to continue to bend (creep) under load, and will not "return" reliably when you unload them. This means that any flexure of the neck would continue to increase (until it breaks?) under a constant load like string tension.

I can't say that I "know" that this is a property of the various teaks now available, but my suspicion is that it is not really a "superwood" for load bearing use. (Further research seems rather pointless due to the prohibitive cost of teak.)

John

Subject: RE: Tech: Instrument building questions
From: JohnInKansas
Date: 05 Aug 03 - 07:34 PM

Crossed thoughts. Of course the last sentence above should have said "various ebonies available" and "prohibitive cost of ebony."

I was recollecting an experience with a similar "oily wood," teak, which exhibited a phenomenal amount of creep when used for a dulcimer finger board - even after I had done some rough checks on the "basic strength" which predicted it was "more than strong enough."

John

Subject: RE: Tech: Instrument building questions
From: Mark Clark
Date: 05 Aug 03 - 10:33 PM

Fender has had quiet a lot of success using rock maple for fingerboards. The necks on those guitars are also rock maple but they're still two pieces for the practical reasons that John mentions and to allow for routing the groove for the truss rod.

Mahogony, as Murray points out, is way too soft for a fretboard although lignum vitae might do.

      - Mark

Subject: RE: Tech: Instrument building questions
From: JohnInKansas
Date: 05 Aug 03 - 11:24 PM

Although I had sort of a disaster with a teak dulcimer fingerboard (it's structural there) it's even possible that teak would make a reasonable fingerboard - with a suitable neck to provide the structural strength. It's a little tough to finish to a nice shine, but it holds a goodly amount of "grease" to make the fingers slide nicely.

Real lignum vitae is almost as rare, and expensive, as good ebony - and causes alergic reactions in many people. I'd save it for those bearings on the home-built lathe - unless of course it's got a pretty grain(?).

The biggest problem with mahogany for a fingerboard is probably the splinters. It's (usually) a fairly "brittle" wood, and especially on sharp edges, has a tendency to pop up little "hairs." Of course, with a good hard finish, you'd really be playing on the varnish rather than on the wood - for a while, at least.

There are a couple of "synthetic" ebony substitutes, probably carbon fiber reinforced "plastics," and they are reported (mostly by those who make them?) as being "almost like ebony."

John

Subject: RE: Tech: Instrument building questions
From: Murray MacLeod
Date: 06 Aug 03 - 03:57 AM

Regarding Cattail's question about using oak, there is no reason why oak shouldn't be used for the sides and back. You would be well advised to make sure that the sides are quarter-sawn, to minimize any bending problems, but the back could be slab-sawn.

Taylor's famous "pallet" guitar was constructed out of oak, and according to Bob Taylor sounds great. Given most musicians' slavish adherence to tradition, however, there is no way oak will ever become a mainstream wood for guitar building.

Murray

Subject: RE: Tech: Instrument building questions
From: Bert
Date: 06 Aug 03 - 12:29 PM

The reason for the large angle on lute and fiddly type instruments is that the friction of the string going around the angle reduces the tension on the tuning pegs. Kinda like taking a quarter turn around a capstan.

With modern tuning machines this is unnecessary and the only purpose of the angled head is to hold the string firmly in the nut. It needs a little downwards pressure so that the string will vibrate cleanly.

The difference between 15 and 25 degrees should not be a problem.

Some lumber yards sell two-by dimensional spruce and an 8 ft. 2 by 8 should be able to be yield many Uke tops.

Bert.

Subject: RE: Tech: Instrument building questions
From: Cattail
Date: 06 Aug 03 - 03:20 PM

Thanks so much to you all for your good advice, as always lots of it.

I suspect I would be better to have a go at one of the projects
given on this site. http://www.ehhs.cmich.edu/~dhavlena/
(or one of the other good sites), first. This would at least let me
make something simple, but playable, cheaply without worrying about
spoiling too much if (When!) I go wrong.

Back to the drawing board, (again).


Thank you all once more.

Cattail 0~

Subject: RE: Tech: Instrument building questions
From: CraigS
Date: 06 Aug 03 - 06:23 PM

While I agree with most of the above, I'd make the point that there is one virtue in a rosewood neck - you can work it much thinner than mahogany, and thinner than maple; if you want the skinniest neck possible, rosewood is the best option.
I've got an old guitar which has a one-piece neck and fingerboard. These must have been a nightmare to make, as the angle for the finger board section passing over the body has to be exact. Mass production methods made tricks like this viable, but you'd waste an awful lot of time and effort to make a one-off. As a related topic, cheaper Martins used to be made without back bindings, eg styles 15 and 21, but Martin discontinued these styles as it was harder to make the back and sides fit exactly, than to rout out and fit bindings (ie it cost more in labour than it was saving in materials).
My memory says that very early (ca 1950) Fenders did not have separate fingerboards, and Fender started using separate fingerboards as the process was automated.
Just a couple of helpful tips:
When trying to finish a piece of hairy mahogany, dust-spray a little clear laquer over it, let it dry, then sand down as desired. If it starts getting hairy again, you've sanded the laquer off, so spray it again, let it dry, start again.
Many guitars made in the twenties and thirties were made without truss rods to avoid Gibson patents - many of these had mahogany necks stiffened by cutting the neck in half and sandwiching the halves around a thin slice of ebony (or maple on the cheap ones). These necks were very heavy compared to modern necks.
When gluing oily hardwoods, one very old tip was to wash the surfaces to be glued repeatedly with benzene or toluene - you can't do this legally nowadays because these solvents are carcinogenic, but it might be worthwhile to try washing or wiping the surfaces with petrol, let the pieces dry thoroughly, then glue them. The tip came from the first book I read on making guitars, in the section on how to glue Brazilian rosewood fingerboards with hide glue.

Subject: RE: Tech: Instrument building questions
From: Cattail
Date: 06 Aug 03 - 07:35 PM

Thanks CraigS for the information about the fretboard-less necks,
I thought that they would have had to be like that originally, before
guitar evolution led us on to better things. That is why I was
asking the questions, (and to save the cost of the fretboard).

Through all your excellent answers I can now see why it is not
practical to do this, (I hadn't considered the problem of getting
the angle right either), given that we can get the parts such as
fingerboards, etc, fairly easily.

I appreciate the tips on working the mahogany Craig, ideas like these
are always helpful, (I must have a search for tips in the forum)
maybe there's another thread already for ideas like these, if there
isn't maybe all you builder types out there would like to start one?

I do find that if I go to MIMF or other luthier sites that they
seem to be geared to people who have a lot of good home machinery,
(most american sites, "Popular mechanics" is one that springs to mind)
seem to be the same way.

In the UK I think that we, (I speak more for myself here), don't
have the workshops that you lucky people in the US seem to have, we
are more kitchen table / small shed in the back garden/yard people,
I would love a good size workshop with table saw, bandsaw, lathe and
pillar drill etc, but I just haven't got the room (or the money) for
things like that, this is possibly why some of my questions sound a
bit silly, I would be trying to do things in a very old fashioned way.

Ah well, maybe one day I'll get a place where.........

I'll stop rambling.

Thanks all, for advising (and listening)

Cheers

Cattail 0~

Subject: RE: Tech: Instrument building questions
From: Mooh
Date: 06 Aug 03 - 09:48 PM

I've never worked with oak any further than to toss it in the woodstove, and a few furniture repairs, but I'm guessing the real reason for not making instruments out of it is the trouble in finishing due to filling pores and such. Hmmm...worth a try though.

I've had a couple of Fender electric guitars with one piece (aside from the skunk stripe truss installation) necks. In other words, no seperate fingerboard. There are practical reasons for not doing this.

For traditional, acoustic, and/or unusual instruments, I prefer construction which can be taken apart to ease repairs and upgrades.

As for tooling, all of the current construction methods owe something to the pure handwork of the pre-electricity era. Many builders still use alot of hand work so there's no reason why you can't either. The one tool I would miss the most would be the stationary sander, mine's a belt/disc unit, because it lets me do some fine fitting I can't do reliably by hand. Second would be the drill press. Spend your money on books and clamps and measuring tools before big power tools.

In the first 3 days of this week I've fixed or upgraded or accessorized four acoustic guitars, one bodhran, one mandolin and one flute case. The only power tool I needed was the sander...tomorrow I'll need the drill press.

Thanks for bringing this thread back!

Peace, Mooh.

Subject: RE: Tech: Instrument building questions
From: Chief Chaos
Date: 07 Aug 03 - 01:00 PM

I've got a contractor on the premises installing wiring using aluminum pipe. It looks like it would also be suitable for whistles/flutes etc. Question is: is there some reason not to use aluminum for this work (where the players mouth comes in contact with the instrument)? We drink out of aluminum cans, but I thought it best to ask you experts.

Subject: RE: Tech: Instrument building questions
From: JohnInKansas
Date: 07 Aug 03 - 01:49 PM

Although we drink out of "aluminum" cans, they're so heavily lacquered on the inside that you're really drinking out of a "plastic" container. Given the number of us who cook in aluminum pots, however, it's unlikely you'd have any problem using aluminum conduit (tubing) to make whistles or flutes. The alloy(s) commonly used are relatively "hard," so you'd expect them not to "bleed off" any significant aluminum crud.

I is also possible to get steel conduit, and there would be more likelihood of a reaction there, as some steel tubing may be cadmium plated (rare). Zinc is the more common coating, and doesn't usually harm most people; although when you drill the fingerholes, you remove either coating so you can expect some local rust.

It should be noted that metal allergies are fairly common, so any metal - regardless of how "inherently safe" it is - may cause problems for a few susceptible individuals.

In either case, thorough cleaning, inside and out, to remove the lubricants used in drawing the tube, would be in order. It's impossible to know what they've used - and they taste nasty.

If you attempt to form a whistle mouthpiece directly from the tube, you will need to look carefully at any solder or other sealer you use to close the gaps. These products are so variable that the individual package is probably your best guide.

Quite a few "homemade instrument" sources suggest both conduit (the metal wiring tube) and pvc water pipe as suitable materials. The "plastic pipe" (pvc) is available in rigid and flexible types, either of which may be "stiff enough" in the short lengths needed. As an "acoustic principle," the plastic might be closer to "wood flute" in performance, except that it's difficult to find any with a wall thickness sufficient to make much difference. Since the water pipe is intended for carrying potable water, there should be little concern about any toxic effects.

You probably don't want to use the black ABS "sewer pipe" for something you're going to suck on.

If you look around a little, you may also find a local plumbing supply (or model builders' shop) that has brass tubing in sizes that will work quite well, although the common sizes stocked are generally in the "too big" or "too little" ranges of diameters.

John

Subject: RE: Tech: Instrument building questions
From: mooman
Date: 08 Aug 03 - 04:35 AM

This is a suggestion that I hope will catch the eye of 'Spaw or Joe.

Following Cattail's suggestion, perhaps there is an opportunity to gather luthery-related matters in a suitable Permathread? There are already one or two in the index but it would be nice to gather the wealth of knowledge already accumulated under a suitable heading.

Best regards

moo

Subject: RE: Tech: Instrument building questions
From: mooman
Date: 08 Aug 03 - 04:36 AM

This is a suggestion that I hope will catch the eye of 'Spaw or Joe.

Following Cattail's suggestion, perhaps there is an opportunity to gather luthery-related matters in a suitable Permathread? There are already one or two in the index but it would be nice to gather the wealth of knowledge already accumulated under a suitable heading.

Best regards

moo

Subject: RE: Tech: Instrument building questions
From:
Date: 29 Nov 04 - 04:55 AM

We have an old guitar made in japan (no brand name at all). It has a reinforced neck which can be adjusted on the front of the guitar. The adjustment mechanism extends out of the bottom of the neck. What we need to know is just what the mechanics of this adjustment does.
Is it a right hand or left hand thread? And when I turn this adjustment, what exactly is going on inside the neck of my guitar and how is it doing it? When do I know it's enough, etc.?
Please help!!!
Thanks