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About fryovanni

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  • Birthday 03/13/1969

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  1. Vac. Bag is probably your best bet for laminating thin woods, especially if you are forming up a shaped part. You really don't need high clamping pressure, you need even pressure. The vac. bag system also allows you to use shaped back forms, instead of top and bottom forms with clamps.
  2. Kp, I am glad to hear you found some answers, and that you have not given up on laminate construction. There are some great design concepts such as using lighter, less stiff but resonant core woods with denser, stiffer and more durable outer laminates that offer some great strength(directional) to weight advantages. Combine that with the artistic oportunities, and it would be a shame to discount laminate construction.
  3. Pete, I am not sure what your getting at. I am not compairing a solid bodies performance to an acoustic, nor trying to corrilate design considerations. I definately have no idea what "acoustic instrument lore" you are talking about. I made reference to some material testing that I had done with regard to spruce for soundboard use, but the reference was regarding general properties and deviation from bit of wood to bit of wood. I made the comments because of the testing that was being discussed. I do believe it would be helpful to think about some of the charictoristics(density, stiffness and such) if your going to try to compair the resonant responce of materials through testing. If you look at my posts in a few recent topics relating to electric/ acoustic "hybrids" you would see I am not one to say acoustics and electric design and function translate easily. Actually, I am probably more enclined to say the two are based on such different systems they shouldn't be confused(although I do respect the opinions of people who find the acoustic design properties integrated into electrics often make for results they find very cool). Kp, You don't need to prove anything here, and unless you are doing this to try to understand the material better to suit your own curiosity, your pretty much wasting your time. As many of those negative plywood posts are out there, you will find as many other solid woods that are also put down for various generic reasons. You will find plenty of unfounded supporting comments for any number of woods or even laminate combinantions. Most of the time these are personal opinions. Even if you provided some silver bullet for plywood here today. In about a week or two you would see another negative plywood comment, likely something about glue killing or sucking "tone" with no foundation short of a strong gut feeling.
  4. And there may be your answer Certainly, does seem like we are wasting a lot of time building electric guitars when we should just be swapping pickups
  5. Kp, I think your search for an answer * is something that is reasonable. You are starting to look down the road a bit though, and are seeing that you are going to have to identify what you are compairing(thus your comment about the wood needing to be of the same type). Given the wood was the same species, the next question would be what are the differences in the two samples of the same species. Is the plywood sample denser than the solid sample? Then is one sample stiffer than the other sample and if so is it the difference related to the plywoods assembly of the wood itself. Hopefully you would be able to confirm moisture content was very close in both samples, but that may take some aclimation time. You would also of course have to be dead sure both pieces were equal in dimension. After you identify the differences(and they will be different) you will have to figure out if the different performance relates to the difference in the properties of the wood, or the by product of the laminate construction. This will be a very daunting task to say the least, especially with limited control over the manufacturing of the ply. It may be that instead of jumping into model analysis it would be more orderly to start with material analysis. That way you can understand the materials, then move to modeling with control or recognition of variables. This way you could for instance insure two bodies used in a test have similar density, even if variables in stiffness are just a by product of the plywood construction, or vice versa. After playing with spruce used for soundboards, and really focusing in on natural ranges of properties from bit to bit. I have really come to realise some significant potential for variation. I have also recognised the significance of certain attributes that account for much of this variation(such as grain orientation, growth patterns, density and such). I would certainly say it is not a total crap shoot as to what properties you will get if you account for these notable features, although you still have smaller variations that are difficult to nail down. Actually, many of those features are also used to develop grading criteria for plywood to ensure some minimum performance garentee(although within much wider range of tolerance, for most grades of ply). I think with musical instrument wood there is a history of importance placed on selection of materials for this reason, at least with acoustic instruments where pushing the limits of efficiency and performance are highly valued.
  6. It is a good thought, but there are a couple things you should consider. manufactured Plywood is very inconsistent. The orientation, grain structure, potentially voids, density of material used, moisture content and such is significantly less predictable than solid wood(at least you have visual clues with solid wood, or even ply you assemble yorself). If you are being true to your testing you have to acknowledge this, and I am not sure how you would quantify the wider range of variance. How you deliver the energy to the string. This is a variable you have to control and repeat consistently, or your results will vary with input. How you collect your data samples. Again consistency, and control over contamination. Range of data and how relevent it will be to a real world instrument application. An open note may produce a bit of info, but instruments have a range of possible positions. How one material acts at a given low range frequency is one thing, but how it acts as the frequency is raised may vary differently from material "B". We understand materials potentially respond differently at different frequencies, and that may have to do with density, stiffness, structure, oils and other factors common to a given bit. Also moisture, temperature and other factors will play a role. It would seem to me that a more productive approach would be to try to understand the corrilations between things like density, stiffness, orientation and so forth. These are common properties that can be translated to a broader range of materials. Bigger tools so to speak. If you limit the study to plywood vs solid wood, and draw conclusions. What about a very dense bit of plywood vs a less dense example, or even a couple bits that vary in stiffness. Bits will vary, so that will be the next step in your study and you will have to start exploring basic properties. Edit; FWIW, I recall a little testing I did a while back. There was a discussion relating to the effect of grain slope on ultimate strength and stiffness in Spruce. I thought I had a reasonable test. I simply used a piece of wood to cut a handful of samples. I split the wood taking great care to control slope. I used the most basic test rig I could think of with attension to consistency. The results clearly supported my beliefs, and I did take measures to blind myself to what material was being tested. However, the test was only as good as the size of the sampling(which is of course pretty limited, as I only used one billet of spruce). It was not a real world model(as in a functional part of an instrument), so other factors may very well alter the results or significance. Even the directionality of forces did not mimic a real world situation. The test had to be simple for control, but that is the catch 22 of much testing. I did walk away with data that showed basic properties, and that is a tool I will use for what it is worth.
  7. I think it is important to look at engineered materials and why or what the intent was. As I was saying, using construction grade plywood as an example. Was that the choice of material and intended application are sensable, efficient, and effective. If you are designing a composite for a neck you should certainly look at the needs and materials you have available. You can then design your material to best suit that application. The Martin neck is a great example. The material that is used for the neck makes sense. We have fewer large, straight grain, clear trees available today. By laminating more pieces that are smaller we are able to use pieces that are all clear and straight grained, all of which can be oriented in the best way to provide strength and stability for a necks requirements. Very sensable. Using other components such as heavier yet stronger materials surrounded by lighter materials to take advantage of design principles that can add to the efficiency is sensable(think of how we construct beams, in situations requiring directional strength). You can follow those principles in body construction as well (think aircraft floors, walls, wings). Now the key to a really good design is going to stem from a really good understanding of your needs. Which is kinda where KP is heading with his research. The trick and where this line of study becomes a challenge is when you get to the subjective points. Basically the requirements will vary with the intended performance. Unlike orchestral instruments we embrace all sorts of distortion from pure tonality in the timbre of our instruments. So your solutions will never be "one size fits all". I think understanding or being able to accept that will help keep your findings more meaningful. By that I mean you will find "soft" material acts in such a way, which is what it is(good or bad? depends). It will also allow you to look at the fact that material is soft, but is also light, and that in a larger volume it has the same weight as another material however it is three times as stiff. A greater unbiased understanding of the materials we can use will give you a bigger arsenal when you are trying to achive a design goal. P.S. Kp, When you say this- If you want to find meaningful information, keep your test simple. You are going to find there are so many variables that may impact your findings in a "full frequency spread available from plywood and solid wood"(not exactly sure what that means) that your results may not have much real usefulness. I have found even the most simple and direct models have variables I did not recognise. Just thought that was worth mentioning.
  8. You make a lot of good points, but I think some conclusions could use a little extra consideration. First of all wood is a fiberous material. The orientation of those fibers depends on growth patterns, environment and species. Although there is a lot of variation in these factors they are not without some sense of uniformity(which can be controlled to a degree with selection). Actually this is the tool used to develop the properties of plywood. Plywood as an engineered material uses averaging of variables to limit variation in charictoristics, as well as make use of more of the material which is available(some of which would not be suitable for a given application on its own). Wood that is comprised of wildly twisted fibers can be sandwiched with other material that is oreinted in alternating general orientations to create some sense of predictability. Now that does not mean the wood is the ideal or even close to ideal per. its total volume, but it has been made acceptable at a certain lowered level of performace within a reasonable range of consistency for its intended use. The sum has become better than the weaker parts it is made up of. If the application requires stability and strength in all directions, and the requirement for strength is in a given range, and weight or efficiency of the material is less critical(Need more strength add more sheets), and of course cost and availability of material is a factor. Using a construction grade plywood for constructing a strong wall or table may be an outstanding solution. Not all the wood used to make the plywood would have met the requirements, and certainly would have not had the same directional strength or stability on alone. A great use of wood for sure. We have to recognise though that you can select wood that is more predictable, has fewer flaws, and orient it as plywood is oriented and assembled. Then come up with an engineered product that is more consistent and stronger than a common construction grade plywood. It is all about averages. To expand on strength and stability. Both of these factors relate to the orientation of the woods fibers. If you need strength on two directions equally it makes perfect sense to take advantage of alternating the fibers(same is true with carbon fiber layups), but if your application requires a significantly higher strength in on direction then you are gaining nothing from this alternate orientation(quite the contrary, half your wood is oriented cross grain which holds about 20% as much strength relative to the direction the strength is needed). Stability in terms of expansion and shrinkage with moisture has similar directional relation and you can actually reduce your effective stability in a singular direction if you choose to mix cross grain orientations(longitudinal orientation varies significantly less than either the radial or tangential orientation. Since the body on a guitar or neck has very directional strength and stability requirements. It would be a wasted compramise for these reasons, although a solid body is VERY over engineered vs requirements to resist string tension(remember an acoustic uses heavier strings than an electric, with a lightly braced, approx. 1/8" thick soundboard and survives) and you can get away with less. So really the advantage to using plywood(again unidirectional and or construction grades) comes down to availability and cost. Lower grades of plywood are cheap and available so this is an advantage. If you actually have an application that requires unidirectional strength and stability. The plywood may very well hold an advantage. On acoustics the tail block and even neck block have these requirements, and plywood has become very popular. So it all comes down to application to me.
  9. You can go to a print house and have it printed. If you plot it as a full size PDF they usually an print for about .25 cents per. square ft.(36" x 48"= 12 sq. ft.). Extra copies of the original will usually cost about half that per. sq. ft. Well worth plotting full size over messing with taping a bunch of sheets and hoping you get the job done spot on. Rich
  10. Well look the plans over and make sure your hardware is the same as shown in the drawing. I am not sure what the angle they are showing relates to. I have always wound up beween 2-3 degrees, but they may be showing something different. I figure it is better to speak up now and have you make sure all is in order, rather than wind up with a suprise. Rich
  11. Not sure if you have drawn out your guitar full size using actual hardware you will be using for measurements. However 4.5 degrees seems awfully strong, you should double check that, else you may end up with a bridge that is set really high. I usually use a flat fretting surface and shape/ cut the back of my necks to accomodate my neck angle. I have a couple methods I use depending on whether it is neck though, Set, or Bolt on. I think Setch had a pretty good topic on his LP. So a search for his topics, or visit his blog. As for sanding(assuming this means hand sanding). Sanding is usually the last method I use to remove material or attempt to freehand accurately. Planes, saws, router bits with guide jigs are much prefered to me. Good luck, Rich
  12. Funny thing is Nicaraguan Cocobolo is usually more expensive, and typically considered a more sought after wood. Mexican Cocobolo is usually slightly less expensive, and easier to obtain. From what I have seen, I agree that Mexican tends to have more vibrant reds and oranges(often much nicer inking). I have noticed the Mexican Cocobolo I have purchased has been more variable as far as moisture content(and I have had most of my trouble with case hardened stock with Mexican), but that has little(I only say little because their may be a difference in the oil and resin content and where it grows could be a factor, but I can't say) to do with the species and everything to do with how or how long it has been drying. Cocobolo is a love hate wood for me, I like its looks and the finished product, but hate working with the stuff. Kingwood is one of my favorites. It is denser than most rosewoods. Which makes it my acoustic bridge choice between Mad. Rose and Blackwood, as its weight 99% of the time falls right between the two. Very nice stuff Peace,Rich P.S. I love the setup Erik. Having those router bits made custom was genious. Your workmanship looks top notch as always.
  13. The route you are looking at isn't for a neck that would go all the way to the bridge or bridge pickup. Often you will find that style called deep set or deep bolt on. A route like the one in the picture overlaps the neck position pickup, mainly because there is little space between a 24 fret neck and the neck PU(wouldn't be much wood left between them). The concept behind deeper necks is to capture either all the pickups and or the bridge in one piece of wood (similar to a neck through), some figure that is good some figure it makes little difference. To me a deeper neck seems to make more sense as a set neck, but if you are clever you can make it a bolted neck also. All personal preference. Peace,Rich
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