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jrhilton

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Everything posted by jrhilton

  1. I'm not sure if any atrists played the exact model you are thinking about, but lots of people have used acoustic guitars with trems on MTV Unplugged, Bryan Adams springs to mind, a lot seem to use a Bigsby Tremolo fitted to the end of the guitar then the strings run over the usual bridge, or else there is some form of non friction ajustment made to the bridge, or maybe the strings don't actually touch the bridge. I would guess a non friction bridge in the style of fenders friction-less roler nut would be best so there is still lots of string vibration transfered to the soundboard. Hope this helps.
  2. 'I'll put the sound of my big 'ol Deep-Bowl USA Balladeer up against any under-$1000 accoustic for unplugged tone and volume' This post isn't really realted to delf-build composite guitars, be in case anyone is thinking about buying a round back guitar, be aware the different bowl debths are designed for different things: For someone interested here are the different bowl debths: Supper Shallow is usually 4 1/16 inches deep, Mid-Depth is usually 5 ¼ inches and Deep is usually around 5 ¾ inches. “If you typically play in intimate settings, the deep bowl will give you full and deep lows. If you play larger venues, a super shallow body will give you additional headroom.”
  3. 'This is probably due to their belief that the back and sides of an accoustic guitar are simply a means to bounce sound out of the sound hole, and not actual contributors to the final tone' Well if we wanted to be 100% correct, the back and sides do not add to the final 'true' tone of the guitar, they unfortunatley distort it, which leads to the 'tone we hear from the guitar' and we believe this to be the true tone, when in fact it is not , if we wanted to hear the 'true' sound of a guitar we are going to have to bring in a band of jolly physics experts to design something for us. Wood has a medium sound wave reflection coefficient in the audable range, this means that it has a higer absorbsion ratio, the absorbed waves then properagate out again because the orginal waves case the wood to vibrate, however they are slightley out of phase with the orginal wave, different woods have different absorbsion/reflection ratios, even the age effects the ratio. So it is true that the wood efects the tone, but it is in actual fact distorting the tone from what it should be, now thankfully we don't live in a world where physics professors rule so guitar manafactures just live with it. Secondley, the original Ovation round backs were not electro-acoustic, they were introduced in 1966 as acoustic modles, electro-acoustic modles came later (in the late 60's). And as for guitar repairs, it is true that many perople do not like composit guitars, I often think that it is becase using composits manafactures take the art of designing a guitar from the workshop to the computer desktop. And people don't like that. Thirdley - I do agree with you about the wonderful range of pickup options avalable now...it certainilly is much easier to play plugged in, but feedback reducing disks are still a worthwhile investment. If this sounds a little like I have trashed your post, don't worry i'm not trying to - everyone has their own opinion, and all are welcome on this page!
  4. Hi to you all again - I'm having a bit of trouble with my internet connection at the moment - hence why I havn't been able to update my tutorial - don't worry I will finish it in the next few days! Sorry about the pictures not showing - i'm having trouble finding a company to host them for free which allways me to load them on this page - can anyone sugest a good free hosting page (they are currentey on Geocities - but as we can all see do not work well!) **Update** 17/10/03 I have switched the images to another hosting page - hopefully they will now work! Please add a post to let me know if they dont - more aditions to my guide in the next few days.
  5. Here are some ideas I have had about making a composite neck (with some additions from my friend who has made one) the easiest way to do this is basically make an exact copy of a neck you already own - I hope this guide also gives people an insight into some of the techniques / possibilities of composite technology. It is very easy to copy the shape of something using composites, there is an expensive way, and a cheap way - here's the cheap way if you are only making a one off or a few copies, the quality is the same. Here are the things you will need: 1) Either unidirectional carbon fibre matt cloth, or glass fibre matt, or glass fibre tape (PLEASE NOTE THE GLASSFIBRE TAPE I REFER TO HERE IS NOT THE SAME AS THE TAPE USED FOR JOINTS ON PLASTERBOARD, IT IS WHAT IS USED TO STRENGTHEN JOINS ON WOODEN BOATS!), or carbon firbre tape, any of these are fine, if you are not sure what these items are have a search on Gogogle, or best of all talk to someone who uses them all the time - here's a tip (I've done some composite work on boats in the past) give a boat yard or marine supplier a phone call for some advice - from my experience they are always willing and able to give lots of useful info / advice. 2) The Resin - there are lots of types available, it may however boil down to expense here - the resin and cloth are really the only 2 slightly expensive items, however they will be considerably cheaper than good quality wood!!! Maybe look for a kit which includes resin and cloth, there are some good value items out there. PLEASE NOTE: 'Cloth' can be used with epoxy or polyester resin, 'mat' should only be used with polyester resin. 3) To make a mould, the easiest way is to either use glass fibre car body filler (available from any good automotive supply/repair shop) or simply use a plaster or filler (like you use on the walls) with some strengthening in it, e.g. hesien cloth or even horse hair ect. Or just plain old car body filler - don't buy anything expensive to make the mould!!! just something which will be rigid. 4) A guitar neck to copy - sorry it is best to copy an electric guitar/bolt on style neck. (if any one is wondering why I am thinking about doing all this, it's simple - don't worry, I'm not mad!!- I live in the UK and good quality wood/exotic wood is hard to come by and is very expensive, however composite technology is far cheaper and stronger, and I have had some experience using it before.) 5) A piece of ebony or rosewood (ebony is the best as it is the most dense therefore will give a better sound, I’m sure there are other good reasons as all the best acoustic guitars seem to use ebony on the fingerboard) for the fingerboard and all associated fretwork and tuning heads ect and binding if you wish ect 6) A truss rod - Ovations use the best truss rod in the business - it's called the Kaman bar - doubt you can buy these – it’s a pity - so either make one (it really is quite easy and for the home builder is probabley better as you can make a Kaman style bar which actually allows you to bold on an acoustic guitar’s neck, if you are making a strat style bolt on neck then an ordinaly truss rod will be fine – If I have time I will post a tutorial on how to do this) or buy a truss rod which has an aluminium channel - here's a link to a page showing a Kaman rod - it does go a bit slow - so give it a chance it should load: Ovation Truss Rod and Neck Kaman Truss Rod Bar I've noticed this page is slow to load so here's the picture of the inside of an Ovation neck - it's quite obvious why they never bend! Here is another page showing Ovation Guitar Neck Construction (Sorry this page is in German - it's the official german Ovation Web Page) 7) Patience and lots of it, and a room with good ventilation - glues stink and are bad for you if you are not in a room with good ventilation - you could do the work outside if it's not too cold! 8) Release Agent - more about this later. Don't worry about the price of these items as you will actually not need all that much, it will certainly be cheaper than buying a ready made neck plus working with composites is good fun. (well I think so anyway) The Process: 1) It is necessary to make a copy of the profile and shape of the whole of the neck (including the headstock and base of the neck!!!). for this guide, I am assuming the use of a fender style bolt on neck, but it can equally apply to a neck which can not be removed. From the copy of the profile and shape of the neck, the actual new neck can be made. Here’s how to do it. Section 1: making a neck mould: Rap your guitar neck in either kitchen foil or cling film (check that the material you are making the mould out of does not dissolve the rapping material first!!!!! Please note it’s not just the fingerboard part – it is the whole of the neck, including the headstock and any mounting parts near the body!) Now onto the back of the neck apply car body filler ect so you get an exact mould of the back profile of the neck, don't worry about the front or else you wont be able to get the neck off. The reason for using kitchen foil ect is to protect the guitar neck and allow you to get the neck mould off your actual neck. Here is a very crude diagram of the ruff idea (hope it loads ok!)- hopefully you will all be able to follow what I mean if you are not too clear: Next you need to sand the neck mould down so that it is lovely and smooth, use filler if there are voids, even allowing for the thickness of the kitchen foil, the profile should be pretty much be exactly the same as the actual neck. If possible use 'wet and dry' sandpaper or really fine grit paper, you may also like to use polishing compound to get a really shiny smooth finish, as the quality if the finish of the neck will depend in part to the quality of the mold! Now here come the options on how to proceed, it really relates to the matter of how are you going to paint it ect......you could use what is called a gel coat which is applied onto the mould first on top of some release agent, the you apply the carbon fibre matt on top of this, gel coat is a coloured glue basically which means you don't have to paint the neck after, however I feel to keep costs down, there is no reason why you can't spray pain the neck instead, this also allows the opportunity of final sanding or fine tuning of the neck profile. Also it's cheaper and easier! A note on release agent - I call it release agent because that's what people understand here in the UK, however it may go by different names in other countries ect.....it’s a liquid which you paint on a mould before applying any composite materials, ect....it stops the composites and glue sticking to the mould so you can actually remove the mould after the glue has dried (you may be able to get around using release compound by using plaster as a moulding material then sanding it off - just an idea). Just describe what it does to a person in a shop and they will know what you mean (or should do if they know there stuff) It's not expensive stuff so don't worry.. For this guide I will assume that you select the option of spray painting the neck after, it's easier....if you are interested in gel coating (this is most likely what manufactures do - then pop along to your local book shop and look for some books on composite boat building or car body repair ect...there will be lots of information available there as well as on the Internet....A good source of composite materials can often be found in marine/boating magazines.....but just check on the internet for the cheapest prices! I will post the rest of this guide in the next few days when I have written it - hope it is of some use to someone - as composite construction it is a really useful skill to have! In case anyone is interested, this actually really the same method that is employed to make large GRP (fibreglass) yachts. Only there the moulds are made of fibre glass themselves for strength and durability so there is good batch to batch consistency in the shape. Update 2: Section 2: how to make the neck once you have the neck mould OK here's part 2: By now you should have the mould for the whole of the neck, the inside of the mould should be lovely and smooth without any imperfections at all, if you used fibreglass car body filler, sand with wet and dry sandpaper for a glass like shine. Next, following the manufactures instructions to the word apply the release agent to the inside of the mould, making sure you put the right amount all over (as per manufactures instructions) If necessary allow to dry for the recommended time. With all composite construction follow these essential steps: 1) Always use a face mask! 2) Use rubber gloves 3) Work in a ventilated space - outside is ok if it is not too cold 4) Make sure during gluing and drying the temperature is within the allow limits described by the manufacturer - don't worry these days the glues can work in quite a wide range of temperatures 5) Mix the glues exactly as the manufacturer stipulates 6) GLUES DRY QUICKLY MOST GLUE IN <20 MINS THEREFOR DO NOT MIX TOO MUCH AT A TIME!!!! Having applied a coat of release agent to the mould, Now it is time to apply the composite material to the on top. In this guide I will assume you are using either glass fibre mat or carbon fibre mat - both are fine, carbon fibre is much more expensive though, you can also use narrow glass fibre tape as well if that’s all you can find. NB: 'Cloth' can be used with epoxy or polyester resin, 'mat' should only be used with polyester resin. Unfortunately the words epoxy and polyester resin are often used interchangeably (like in this document I'm afraid)- my best advice is to seek advice when buying the products such as glue and mat or buy an 'all in one pack' they are often the best value!. People at shops are always very helpful when they know you are about to buy something (well most of the time anyway) First lay the mat out on a table and (if this is your first time using it) look at the construction of it - it's a weaved mat with strands going at 90 degrees to each other, unidirectional carbon fibre mat can look slightly different, but you will see what I mean. When applying the mat the direction of the strands must not line up! THE DIRETION OF THE STRANDS MUST BE AT 45 DEGREES FOR MAX STRENGTH. Cut the mat to approximate size, don't worry if it's not large enough, it's ok to overlay pieces. Now here is the process - for more detailed descriptions read the manufactures instructions or search Google. 1) Having applied the release agent directly onto the mould, Apply a generous layer of epoxy on top of this. 2) Now place the mat on top of the epoxy 3) Using AN OLD brush, with brush strokes, push the mat into the epoxy till the epoxy soaks through and the mat is inside the epoxy as it were - do not push it in too far! 4) now apply another coat of epoxy on top of the tape and brush in Now here come the variations, some manufactures suggest letting each layer dry before applying another, some say let it dry a while then apply another some say apply straight over a wet layer, do as the manufacturer of the glue / mat suggest. Next put on another layer of cloth using the same method as above but excluding the application of the release agent obviously! Here’s the process: Generous layer of epoxy --> bed cloth --> apply another layer of epoxy on top of cloth --> Repeat Make sure that direction of the fibre strands do not line up, they should be at 45 degrees to the previous layer. And don’t put too much epoxy on (this sounds like a contradiction to my previous statements, but too much is bad – my best advice is practice, you will soon learn how much epoxy to apply) Here is an image of carbon fibre cloth, just so you see what I mean by strands: Here is an image of glass fibre cloth And here is another image I hope you see what I mean by the strands, and that they must be at 45 degrees to the previous layer. Now, there is the tricky question, how many layers should you put on? Well the answer to this depends on how thick the mat is that you are using, mat is sold by weight, so the heaver the weight of the mat, the fewer layers you will need, more is always better! Remember there will be a truss rod in the neck, even with composite necks I would still guess a truss rod is essential as different string gages vibrate different amounts and you want to be able to adjust the height of the action. An aluminium channel truss rod may be a good investment, theses often allow you to adjust the neck to bend more or less, and that’s just a thought, as always I think it will be a case by case decision, but definitely have one! You may find that after you have applied a few layers of cloth you can safely take out the ‘new’ neck out of the mould, when the layers are dry see how strong or flexible the neck is, if it is still too flexible, add more layers of cloth to the inside and bond in in the same way as before with resin. Now here comes another part where personal preference or opinion may weigh, people say a dense neck is better as the strings will resonate better, yet I believe you also loose the great highs. The Truss rod will add to the density of the neck, but you may wish to add more material to the inside of the material, consider bonding in some carbon fibre rods to reduce flexing m(cover these or any other bonded materials in plenty of epoxy and bed epoxy cloth on top as well so there is good bond between different things, you don’t want them vibrating inside the neck!, or bond in some pieces of ebony wood to increase the density of the neck, maybe even fill the inside of the neck with lead (now that is an idea for you all to ponder, I’m not recommending it, though I may try it one day). Section 3: the fret board I have given this a fair but of though and think the easiest way of fixing on the fret board is to bond in some pieces of hard wood onto the side of the fret board part of the neck, and fix the fret board wood on using good old wood glue. Look at the diagram to see what I mean. Before fixing on the pieces of hardwood, it is probably the best time to approximately level the top of the neck where the fret bard meats the contoured part of the neck. Level it at the same height as the original neck, just use a file or fine saw. Don’t worry if u don’t get it exactly right as you are gluing the fret board onto the hard wood supports (these hardwood supports should have a flat surface on the top), so you can fill any gaps between the fret board and neck and paint over these after. I am currently thinking about the best way of bonding in the truss rod, any suggestions from anyone would be great, I have a ruff idea about the best way of doing it, I will post my thoughts on this when I have come to a decision on the best method. Section 3: the headstock My thoughts about the headstock are like the rest of this project - ‘KIS’ – Keep It Simple!, I think the best way is to bond in a piece of wood that is shaped to fit on top of the layers of composite cloth and epoxy and then put another layer of cloth and epoxy on top, so you can sand this smooth and get a glass like finish, also then there will be something solid (the wood) to fix the machine head screws into. Here’s a picture of what I mean. Section 4: the truss rod Unfortunately it is not possible to buy a Kaman truss rod in a shop so we will have to make do with something else (unless you are good at welding in which case it would be easy to build a rod – I will, if I have time post a tutorial on how to make a good truss rod from easily available materials.) I have given this part a lot of thought and think I have come up with a good solution to mounting the truss rod. There are two possible options I have though of, obviously there are lots more, it may be a case by case decision here, either of these should be suitable, the choice you make may boil down to what truss rod you are able to buy or make. OK sorry about the diagram – I think it is the worst yet, but hopefully it should be clear what I mean. Option 1: This uses a length of steel threaded rod (easy to get hold of). On one end is fixed a permanent anchor, e.g. a nut welded on or the rod bent 90 degrees. The other end has a normal nut or truss rod tightening nut screwed on. The truss rod is fixed onto the neck using 3 blocks of wood. The fist block of wood is at the nut end of the fret board. A whole is drilled through and the piece of wood is fixed to the neck using epoxy and cloth by running the cloth around the block of wood, allowing overlap on each side onto the neck. The next block of wood with a hole drilled though goes around the 12th fret (the exact position depends on you view of how the truss rod should be bent) Again this is fixed down to the neck using epoxy and cloth. Notice that the hole that the truss rod goes through is much nearer the back of the neck. The final block of wood is at the bass of the neck, it will be here that the nut for adjusting will be placed (you could design a system where you tighten the truss rod from the headstock end if you so wish). Again this block of fixed to the neck using epoxy and cloth, and has a hole though it for the rod to go through and a hole if necessary for the tightening nut to fit into snugly. Each of the blocks should go from the back of the neck to where the fret board will fix on for added strength and effeteness. Option 2 Using a piece of wood (preferably hard wood to increase the resonance of the neck) plain it so it fits snugly into the neck as show in diagram number 2. Now rout a channel for the truss rod as for a standard wood acoustic /electric guitar and glue in a filler strip on top of the rod necessary. Next fix the piece of wood holding the truss rod into the neck by covering it in epoxy and cloth. On the diagram the black lines represent epoxy and cloth. The block of wood should be covered in epoxy for good strength and so the truss rod will work well. The layers of epoxy and cloth should not protrude above the place where the fret board will be glued on, it should be level. As the fret board will also be glued onto the epoxy which holds down the block of wood for extra strength. Sorry if this is not all that clear. Please note on the diagrams – grey= wood, blue = truss rod /(truss rod components in diagram 2), on diagram 2 the red is the pieces of wood glued onto the side upon which the fret board will fix. Brown is the fret board. Another tip when installing a truss rod is cover the rod / fill the channel with silicon sealer (the flexible stuff). The rod will still work fine and it won’t vibrate in the channel. Section 5: the base of the neck Again more to follow soon, As with the headstock, I think it would be a good idea to bond a solid piece of wood into the base of the neck where it fixes onto the guitar body so you have something solid to fix the mounting screws into. Again any hardwood it suitable – a softwood could be substituted if hardwood is not available, but hardwood is preferable because it will provide a stronger joint and will resonate better. Again what you do here really dependes on how you fix in the truss rod, if you mounted it in using a pice of wood then you can also use this pice of wood to fix the neck bolts onto. Section 6: Final Preparation The next stage involves lots of sanding, and filling if necessary. With composites materials, using wet and dry sandpaper, a glass like surface can be achieved. If there are any voids fill them with epoxy and some mat for strength. A common error is to fill large holes with epoxy alone – epoxy on it’s own can crack, yet when bonded with cloth it is much stronger and will not crack. So if you have to fill large holes always use carbon/glass fibre tape or mat with your epoxy. Section 7: Painting More to follow soon.. Here’s a quote from a later post: ‘so jrhilton, what are you going to put in that carbon neck you have drawn so far? leave it empty? put filler in it? try and fit some wood in there? this arises the point of, maybe you should start with a peice of basswood (as per parker guitars) that is designed to be slightly smaller in all ways to allow for a pre determined amount of carbon to be applied on the outside of the neck. this would also make placing the truss rod and attaching the FB a no brainer. But doing so means you'll need alot more finishing work on the outside of the neck when done vs your mold method, and most if not all parker's to my knowledge are a form of neck thru electrics so messing around with proper heel dimensions is not an issue in that case.’ This is a good idea introduced by krazyderek, there is no reason why you can’t build a neck that is slightly smaller than the desired final dimension then apply a few layers of carbon fibre cloth on top. However the only word of warning here is make sure the layers of Expoxy are not too thick or cracking may be a danger. The truss rod could be fixed into the wood before covering with epoxy and mat. What I would do for maximum strength would be to cover the whole of the outside diameter of the neck with mat and epoxy, not just the back and sides, then glue the fret board on top of this, this will be far stronger. Plus composites can be sanded down to a lovely smooth finish and no one would know there is a pice of cheap wood inside. With regard to finishing the neck if you choose to do it this way, well it really is very easy to sand the epoxy and mat down and it is also quite easy to get a nice fairly smooth finish when applying the mat in the first case. I guess it really all boils down to personal preference. In many ways I would say for a first time builder it would probably be easiest to go with the rout described by krazyderek above and just put a layer of composite material over a smaller neck to bring it up to the right size and add strength. It would be worth doing that just to get a lovely glass like finish to apply paint on top of – but a word of warning, don’t just apply a layer of epoxy without any cloth as it will more than likely crack without any reinforcement. I will add more to this guide in the near future – sorry it’s taken time, my Broadband router died on me last week and have had intermittent internet access since.
  6. nyjbkim - I will try and get some photos from my friend- but in the meantime - if u want any information about Carbon Fibre molding / techniques - feel free to post questions to this page - I will try and answer them as best as I can as I have done quite a bit of Composite work on boats. My friend already had an ovation, so he basically (using standard molding techniques) made an exact copy of the shallow bowl body and then made the top using a 3 layer process of carbon fibre, balsa wood, and another layer of carbon firbre on the other side - sounds week but you can walk on that, after all how many people do u hear of who have fallen though the floor on a boeing 747 - same building method is used there! As I said - if u have any questions just reply to this post and I will try and help - I am interested to see how much interest there is in composit guitar constuction for people building their own guitars as I could not find much on the internet - hence my origional post.
  7. Roli - thanks for the reply – your absolutely right – there will always be people out there who will not like it, however carbon fibre sound boards can be designed to sound how you want, so there is no reason why you cant make it sound like a 50 year old AAA-grade Spruce top if you can work out where and what thicknesses are necessary on which parts of the soundboard – alas that is way out of my range and ability! But as good wood becomes harder to find Carbon Fibre will become the choice material I think. I mean just look at Gibsons, the wood they use for their new guitars is not of the same high quality as the wood used in their pre 1986 guitars. (Again just like there are die hard fans of wood guitars, there are also die hard fans of Gibson, some people just will not except that since Juszkiewicz and Berryman bought the then bust Gibson in 1986 quality has gone down- but that’s another story for another post!.) Since I posted my 1st post about composite bodies, I’ve been thinking, does any one have any opinions about composite necks, I was thinking a mahogany neck with a truss rod like the Kaman rod so it will never bend, however I see no reason why I could not also make a neck out of carbon fibre with an Ebony fret board glued on – how will this effect the sound as the neck will not be as dense as a wooden one, so will it not vibrate as well? Anyone?
  8. Has anyone tried building an acoustic guitar out of composites instead of wood (this refers to the body). For example using a sandwidge of carbon fiber and popular or even balsa wood for the sound board. (Allowing a very rigid and thin board for great highs and good volume.) And a composite guitar body. The reason I ask is I have a friend who basically made a copy of an Ovation, he already had a Custom Legend (In my opinion the best acoustic guitar money can buy) and basically copied it only building the whole of the body out of composite including the soundboard. I must say it really does sound very good, and it cost him less than $100 to make including the wood for the neck and the metal to make a copy of the Kaman bar and he got some old Schaller tuners off Ebay. Has anyone else considered making a bowl body for a homemade guitar – having used composites before when repairing boats I feel I would be far easier to make a great guitar out of composites than out of wood. Of course there will always be people who don’t like the sound of composite guitars – I for one think they sound great, the tonal definition, volume and strength speak for themselves – for anyone who doubts composite technology, the should play an Adamas made by Ovation. Just in case people are wondering – don’t worry – I’m not advertising Ovation! It’s just I feel I could make a replica/similar guitar for far less than the $2000 price of a Custom Legend, and if that makes me sound cheap, I have nothing against the quality of or price of Ovations, it's just I have an expensive wife, so now i'm sure you understand why I don't want to have to spend $2000!!!! Anyone have any views on composite guitars or conposite constuction?
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