Agreed, 100%. I studied instrument making and I've made a few guitars, mostly electrics, but I've learnt so much from these videos. The sheer amount of knowledge, shared in such a concise and detailed way is a true joy. Thank you Ken, for sharing your time and knowledge with us mere mortals!
I've watched hours of YT videos about trees, wood, and sawmills in the last year but apparently I was still not clear about much. Now I am and I feel empowered! A few minutes of you explaining things continues to prove more valuable to me than I can even express.
This is great to hear, as I wasn't sure I had really done the best job. Still, there might be a short film to come trying to clear it all up. There are so many regional terms that it can get confusing, as well as multiple names for the same thing. Really, the thing is about what's on your bench, not so much how it got cut that way.
Thanks Ken, I've never owned one of your guitars though i have played some and i don't think anyone would dispute your status as one of the great instrument makers of the twentieth century. It's great to see you sharing your knowledge.
Beeing a guitarplayer and certainly not anyway near to beeing a skilled woodworker this is not only informative and very interesting. Its almost a magical world. Thank you Ken:)
When I started getting hard core about the materials science of woods, I found that woods are basically made up of 3 types of molecules: big soft ones (jelly beans), small hard ones (bb's), and springy ones (like the spring from a click pen). Wood is a conglomerate of these in different ratios. The different ratios yield the different behaviors. Hard = lots of bb's, fewer jelly beans. Stiff = lots of springs vs bb's and jelly beans - and so on. Wood with lots of springy molecules ought to be good for necks and acoustic tops and backs. Wood with lots of small hard molecules should transmit vibrations better with less loss - IE better "sustain". By looking at the wood charts for density, specific stiffness, hardness, etc, you can get an idea of what woods are what. Pine is soft and kind of stiff, so its mostly jelly beans, some springs, and just a few bb's. Apparently, Douglass Fir has the 3rd highest specific stiffness in the world after a restricted African wood and a rare local only Australian wood. So, it should have lots of springy molecules. For a neck, zero deformation would be ideal. That would require a very stiff material such as carbon fiber. I've had success building necks consisting of 3 carbon fiber tubes backing a conventional fingerboard with no truss rod.
Thanks so much for this! Fascinating! Please, can you direct us to source material? I suppose you're using golf club shafts for your neck? If not, do tell. The shafts I've seen are tapered, which is ideal for this use. Also I've seen that they are available in a variety of sizes and fiber orientations designed to control stiffness in bending and torque. I think these shafts use some high strength epoxies cured at elevated temperatures in order to make full use of the carbon fiber's potential stiffness. What material did you choose for the fingerboard? What type of resin is used to stick it all together? I get that an adjustable rod is not needed if you have control of the stiffness and build a structure that is not susceptible to creep. This is what I've done in my current neck design. Bravo, thanks for the lesson, and please expand!
I don't know that Douglas Fir being 3rd is accurate. Based on numbers from The Wood Databse, Spruce has a much higher specific stiffness(surpassing aluminum and titanium even), and I've seen a video from a university professor specifically talking about Spruce being at the top for this property.
Thank you for your work and all that you do on these videos. Most interesting and very informative. As an older student of guitar I learn so much from your wonderful presentation. Your Arch tops are so pleasing and sound fantastic
It's such an interesting material, really a group of materials. It has its challenges, but it can really be the right choice for some important instrument parts. It's the wallflower of the conifers!
Hi, Ken… I used to have logs sawn through and through and have the hearts “boxed” by sawing a 3-4” slab, which yielded beautiful, vertical grain pieces. Usually, I was sending veneer grade logs to the sawyers.
Great! this is the perfect way to harvest the best material from a log, in part because the sawyer can judge how to rotate the log to get the best big center slab. Are you still sawing? Sounds like fun.
Good info Ken. I was bending sides for some 335s I was building. I did a maple and a mahogany. Being new at it I thought the maple was hard to bend but I restored to soaking the mahogany in ammonia.
Careful with that stuff! Poisonous AND explosive. There was a time (50-ish years ago) when lots of folks were trying to use it for extreme bending, and it does work very well, but the dangers proved to outweigh the benefits, and you don't hear about it anymore. Please be very careful and use a supplied air system. Most builders manage to achieve good results without it. I suggest thinner wood, a bit of water, and a good plan executed briskly so you get it right the first time. Practice is Very Helpful!
@@kenparkerarchtoppery9440 I was careful but yes it could get bad if you don't ventilate. I was using three 1/16" pieces (.062) laminated after bending. I think I have video of the process on my channel.
Do all of the materials deform and return at the same rate? It will be interesting to see the longer-term results, but would also be nice to measure the deformation immediately after the tension is relieved, then at one hour, then at one day.
Experimenting is great, but the point is that guitar necks tend to be a hot mess, and I'm trying to show why this might be, and how to steer around the physical challenges so that when we build high quality guitars, we can rest assured that our work will stand the test of time and not need open heart surgery.
@@kenparkerarchtoppery9440 I'm sure all will be revealed! And your central point (and previous industry innovations) will likely end up supporting that the CHOICE of wood isn't so consequential as construction technique (lamination, truss rod, carbon fiber support) or getting away from (solely) wood in the first place.
that picture at 8:00 is odd, the board labeled quarter sawn is quarter sawn technically but not really sawn off the quarter. The board labeled rift sawn is coming from the side that's more or less quarter sawn. At least I think so....
Well, there you have it, "quarter-sawn" may be less precise than we would hope for, whereas "vertical grain" is more descriptive. Tolerance is raising its head here. Does vertical grain mean 90 degrees plus or minus zero? I suppose it means different things for different folks. As I mentioned, it's a matter that folks will disagree on.
19:50 yes this is what I've encountered when bending my mahogany side. It was tough, I have this african kind, which is even harder to bend they say. But when it was done, it hasn't moved even a little back since. So really pays to do it as perfect as you can. Overall, I try to make my guitar in a way that when I will do assembly of whatever part, I don't have to put extra stress in it, it's all got to go together just as it is. So trying to make my sides and plates as flat as possible etc. This is btw a reason why I like an archtop concept over a classical made top. Because with the classicals they push the flat timber into a curved shape, so this in my view creates tons of stress into the instrument, which as I see it, just has to release over the years somehow and deform whatever you've made. But I'm too inexperienced to judge on such a thing though
This raises a whole series of interesting questions! What happens when you put a large, steady load on a structure made of thin material? It seems that he strings' forces will likely greatly exceed any persuasive pressure we'll need to help parts join during assembly. Although your concern is voiced by many in the field, I've never been convinced that the "perfectly stress-free" goal is especially meaningful, within reason, of course. As a repairman, my experience was that the strings challenge guitars over time in ways that must be far greater than the small forces we would apply to get things aligned during building. I have never built a flat top instrument of any kind, but I believe that the induced dome shape you refer to has proven to be very helpful, and is widely done today. In this example, the top plate has an induced pre-load that helps it to behave while heavily loaded. Hope this helps you think it through. BTW, don't feel bad, nobody thinks that bending is easy.
I know this is a sort of torture test, and not really supposed to be representative of string load, but it might be interesting to see how they would respond when the wedge is convex, so that the stress is from the tip of the wood samples instead of right at the tip of the wedge!
There's not a lot of data on this, but on the data that is available, it seems to show that quartersawn and flatsawn wood does not differ in stiffness very much at all(with the grain). In fact, flatsawn might even be stiffer in some cases(again, limited data). Quartersawn is significantly more dimensionally stable, and that is enough reason to use it. The only reason it would be different is from fiber distribution(which would vary significantly from board to board, and probably averages out for the most part), and differences in how the grain handles shear stresses(which the data seems to indicate is not significant for this). Cross-grain stiffness is a separate issue, and that would have benefits for tops and such, but that doesn't hold for beam structures like necks.
Excellent points, especially on the lack of data. I believe we all gather the data on the bench, whether formally or informally. You make a good point about material stiffness, but let's remember that the wood species are all wildly different, and need to be judged as individuals. In some species, flat-sawn material can meet the stiffness of vertical grain material, and on others, it's not even close. Of course stiffness is only one concern, as you mention.
@@kenparkerarchtoppery9440 wouldn't all the $100k 52' telecasters that are still playable show that in general, maple necks are pretty stable regardless of grain structure? I'm asking...it seems like these instruments were not built with excessive care but have, in general, survived, even despite great abuse and neglect.
MOST DEFINITELY!!! YES!! From 1978 - 1982 I ran a big repair shop at Stuyvesant Music, right off the corner of 48th street and 7th Avenue, NYC. We were offered hundreds of "Vintage" ( of course, at that time they were all only 20 - 30 years old) Fenders and Gibsons to purchase or repair, and I worked on hundreds of them myself. I can't begin to tell you how many of these instruments showed up in completely unplayable condition, mostly due to creep induced deformation, that's right, unplayable. The prices were just beginning to pick up, and many of my customers agonized over the decision of whether or not to have their '54 whatever it was refretted so that they could play it, or just put it in a vault and weep, hoping to make a killing on an original condition piece later on. One thing I found very interesting was that most of the "OST" (that is, unplayed and unmolested "Original Strings and Tags") guitars were utter dogs, and had been pawned off by the dealer to somebody who never played this awful sounding or unplayable guitar, or perhaps were planning to buy it for a gift. No surprise, the good ones got sold and beat up, for the most part. The world has changed so much now that no one will ever have the chance to have this perspective again, but I Promise you it's true. OST's were often the worst instruments.
Well,,,, curious about something. Are all the pieces the same age? And have any been subjected to forced so called aging.? It's kind of important to know. Will those pieces go back straight after some time? You know as well as I do any wood changes dramatically with time in atmosphere. It would affect the test, don''t you think? Old wood has a better memory for sure. Hmm, some pianos used Honey pine for ribbing,,just to note. For lightness, stability and end grain strength.
Not sure I can usefully respond to all of this, but, no, the pieces don't go back, they don't "remember" being straight, and this is the whole point of this exploration, to try to find a way to deal with this shortcoming in wooden materials. How on earth could one ever know what old material might do differently when there is no possible way to test a sample with and without age?
Don't know each piece for sure, but nearly all material for sale has been in a kiln, don't kid yourself. If you fell a tree yourself, saw & stick it, you can have it your way, and that might be better sometimes, I'll give you, but good kiln drying done by real pros is not going to injure wood's mechanical numbers, unless you can cite something I've not seen. Perhaps you're over thinking this, I was only hoping to show that wood doesn't remember being straight after it's loaded for a time, it was supposed to be a playful demo. The truth of this is beyond any dispute, no matter how old the material was, or how it was dried. It's just what happens when you lean on wood. I promise! Just look at guitars, and you can see what happens
Have you ever experimented with hollow fingerboards or cf rods flat under a fingerboard to reduce weight? I got enough Lignum today for 2 fingerboards and they’re so heavy…
It is fairly common practice in classical guitarmaking, I understand, to reduce the weight of an ebony board by "hollowing "it from the bottom with a shoulder plane or dado cuter, and gluing in spruce or some other light material. Alternatively yu could use a thin layer of hard, dense wood and laminate it to something light, using binding to hide it. Carbon/epoxy won't be helpful here because it weighs about 97 lbs/cu ft, heavier than any wood. Carbon/epoxy is very useful stuff, but I think it's not very well understood, and so it is often mis-applied. A little, in the right place, goes an awfully long way.
I concur! With the web information is so readily available, this series is gold for luthiers. Remember entire evenings spent at the library searching through the card files seeking information on a given subject, followed by more evenings trying to find specific information on the subject? Spent years searching for data that a search engine would find in seconds. But then the overload of advertising and “kind of “ by newbies I guess balances that out. West Chazy know that if Ken sez it, it’s gospel! Golden! What a service he is doing for the art😊
Wow! Does that mean we'll still have Books? Terrific! Thanks, I'm happy that so many of you are finding Archtoppery useful. I'm tickled pink to have a platform for my fascination with building tools for musicians. Thanks to you all for your comments and your co-enthusiasm! Instrument making has been a magnet for inventive problem-solvers for 43,000 years, if they've got the date right!
West Chazy? Well anyway, thanks for your praise and support. It continues to be big fun for me. Just make sure you're packing some grains of salt, highly recommended.
