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hey, thanks for the link..very informative. i don't make enough guitars in a year to justify the expense of one but after reading ron thorn's reply i can see why they'd be great to have.

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and since i don't want this thread to depend on the stability of that other site...here is ron's reply

Ron Thorn

Contributing Member

Registered: Nov 2003

Location: Glendale, CA

Posts: 118

I'm game.

First off, there is no shop, large or small, that is entirely CNC. It does not exist. I think most individuals would be surprised by what a guitar component looks like when it comes off a CNC. It is no where near complete, there is still plenty of hand sanding, fitting, etc.

Here's a break down of what I do with the CNC and "by hand".

CNC:

Fretboards - you asked "why

they've gone to the CNC and what aspect of things is better". The fretboard is so brutally important that it is ideal for CNC accuracy. I perimeter, slot, radius, and rout for inlays all in one set-up on the CNC. Than insures spot-on fret slot placement (VERY important to the quality of the guitar), consistent radii including compound radiusing, and inlays that are very tight and free of sloppy filler/gaps.

Total time on the CNC: 20 minutes

Necks - Once the blank has been bandsawn ("by hand") to an oversized shape the CNC will machine the neck carve, perimeter the neck and heel, shape the headstock, drill for tuners, rout for truss rod and rout for logo & purfling. This is done through 6 different set-ups.

Total time on the CNC: 1 hour, 45 minutes.

Bodies - The CNC performs all cavity routing (top & back), neck pocket routing, perimeter, top carve, and bridge location holes. On a pivot style trem, such as a PRS trem, the location of those 6 holes must be perfectly inline to prevent binding of the trem during use.

Total time on the CNC for a body with carve top: 3 hours

Inlays - Production inlays, such as my Firesuns and "T" logo, are cut on the CNC for a perfect fit into the routes on the fretboard and headstock. I also "rip" my purfling strips on the CNC too.

Total time for one guitar's worth: 15 minutes

Components - I machine my own 1-pc. brass tremolos, pickup covers and rings, knobs, back plates, truss rod covers, and jack plates.

Total time worth: Approx: 10 hours.

Granted, all of these parts are "custom" for my guitars exclusively. I could purchase all of these parts from guitar supply shops but prefer to make my own.

None of the above times include any programming, set-up or material preparation...all of which are done "by hand".

_____________________

"By hand"

This term, I assume, includes feeding or pushing the component through a power tool such as a planer, jointer, drum sander, bandsaw etc.

Fretboards:

Pre CNC: The wood is bandsawn to an oversize thickness and feed through a drum sander to flatten.

Post CNC - The fretboard needs to:

Have the side dots drilled and glued in.

Inlays and purfling glued in.

Glue the board to the neck blank.

Level and true the board.

Fret and fretdress.

Total time "by hand": 13 hours for the above operations. My fret preparation (cutting to length, nipping the tang, grinding the tang), fret installation and dress is a total of 6 hours alone...no CNC for any of those operations.

Necks:

Pre CNC:

The wood is milled and rough cut to shape, using tracing templates, on a table saw and bandsaw before it gets to the CNC.

Post CNC:

Install the truss rod and filler strip,

blend the neck into the fretboard,

inlay logo and purfling,

final shape the neck carve to spec using rasps, spindle sanders and lots of elbow grease sanding then sanding some more,

gluing the neck into the body.

Total time "by hand": 8-10 hours easily.

Body:

Pre CNC:

Split top, joint edges, bookmatch glue together, sand to thickness.

Mill/sand body to thickness.

Locate and glue top to body spread then sand and drill locating hole for the CNC.

Post CNC:

Inlay purfling.

Drill for controls, side jack, wiring channels.

Radius back edge on router table.

SAND from 150 grit to 320/400

Total time "by hand": 10-15 hours depending on the wood species.

Paint:

Prep, mask off, stain, seal, color, top coat, lots of sanding in between, lots of sanding after, buffing...the list goes on. No CNC for these ops.

Total time "by hand": 28 hours if all goes right the first time...it never does.

Assembly:

Installation of components (tuners, pickups, bridge, etc), wiring, cutting the nut, set up.

Total time "by hand": 6-8 hours

The above is only visually productive acts, not including ordering wood and components, e-mails, shipping, and just plain running the business.

_______

So, if we deduct the custom components and use off the shelf bridges, pickup rings, etc. The average total time is:

CNC: 5 hours, 20 minutes.

"By hand": 69 hours, 30 minutes.

I consider my shop to be fairly state of the art, I have a large HAAS CNC for the woodwork, and 2 smaller CNCs for the pearl inlay work. The only additional automated CNC-type machinery would be a Plek and a robotic buffer. I could see that only reducing the "by hand" total by a couple/few hours at most.

Not mentioned would be a custom one-off inlay that I, or my father, would do "by hand" with a jeweler's saw and a mini router. The time spent on that could be from 45 minutes to 100s of hours depending on the design.

However small in comparison those 5 hours, 20 minutes seem...they are VERY important to the outcome of the guitar. Accuracy and consistancy are unmatched. There are features, such as my double offset purfling, that just can't physically be done by hand. Fretslots accurate to within .0005" of an inch...heck, the wood will expand or contract more than that by the time I turn the lights off in the shop at the end of the day...but it's good to know they are as accurate as can be.

Inlays that are gap free and clean are important to me. I'm not a fan of filler and I don't want that to be a part of my product. Even with hand cut and routed inlays, I feel we are one of the best at making them tight and clean.

Can I build a guitar with out a CNC, sure.

WOULD I now if I didn't have one...I doubt it, because I would always feel the guitar isn't as good as it can be WITH the help of a CNC.

There you have one take on it from a CNC builder.

Ron Thorn

www.thornguitars.com

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Here is a follow up entry from Joe Driskill.

Diablo

Senior Member

Registered: Jan 2002

Location: Fort Worth, Texas

Posts: 220

I don't think I would ever want to do this without a CNC. Not for time savings at all but for its accuracy and possibilities that it provides. I have a HUGE Haas. My upper horn was ½” longer so I had to go with a really big one. $109K just for the basic tool. It took five years to pay for. It sits a lot of the time since I do so much handwork. I named it Slacker for this reason. When it is doing something though, there is nothing else like it. Nothing comes off of it ready to go without a lot of sanding or, in the case of metal, buffing and plating. Here’s kind of what I do with each thing.

Fretboards- cut locating holes on the bottom, vacuum it to the next fixture, cut perimeter and arch with a ¾” Ball endmill. Time: 40 minutes.

Fretslots- .020” endmill cuts fretslots. Tiny little thing which breaks easily if pushed too hard. Time: about 38 minutes.

Inlay- Totally depends on inlays. Almost all of them are custom in some way. Time: anywhere from a few minutes with simple dots to days with more elaborate inlays. One took about 12 hours just to cut the pearl and untold hours to program. The wolf guitars took an unbelievable amount of time to program and cut. I couldn’t even estimate how long they took. We’ll just say about 4 hours for a mid range difficult inlay which is all ready programmed and only has to be cut and inlaid.

Necks- rough cut to approximate size and then put on Haas. It takes 3 fixtures and a ton of steps with all kinds of tools to cut necks. Total time: about 1:30 hours I guess.

Bodies- three fixtures and some off an on back into the machine after gluing stuff . Time: about 3:30 hours total machining time.

Metal parts- I make my own pickup rings, stop tails, and trems. This is like getting a sex change to switch from wood to metal. Every little spec of wood and dust has to be cleaned out and the machine wiped down. Then coolant has to go in it and be all hooked up and the air disconnected. I made vise jaws for everything. There are about 16 or so sets of vise jaws to cut different metal parts. Big hassle! Each one has to be put in and then located with dial indicators. Trems- time about 4 hours probably. I don’t even know on the other stuff but it’s not quick.

Components- knobs and back plates- probably about 20 minutes machining time.

Hand work:

Fretboards- tons of sanding and stuff after tweezers put the inlays in. Lots of sanding and buffing of the fretboards. Before going into the Haas, they are run through a widebelt sander to roughly size them. Then the inlays go in. The frets are stainless steel and both epoxied and pressed into the fretboard. They are then clamped up in aluminum press plates with the radius machined into the plate. This is clamped up and let to cure for about 10 hours. Then the fretboard is glued onto the neck using epoxy. Again the plates clamp this on and it cures. No moisture is ever introduced to the neck since epoxy is used. That all takes about 4-6 hours of actual work and lots of curing time.

The neck is then sanded to shape as it is cut way oversized by the CNC. I make my own carbon fiber and it has to be put in. Then the side dots are drilled and installed and the tuner holes are drilled with a drill jig. Then the neck goes back into the CNC for the tongue angle. Lots of handwork on the necks! Total hand time on necks: 10-15 hours including the making of carbon fiber and cutting it. Probably way more time if I consider that.

Curing the UV finish: This only takes about 10 minutes total in the CNC UV booth.

Body:

Lots of sanding and looking at it. Taking pictures, photoshoping it to find stuff, etc. Resawing it and stickering it in front of fans to get it good and dry. Running it through the sander and gluing it onto the CNC’d parts. Vacuum bagging it to dry, etc.

When it comes off of the CNC, it has tearout and is pretty rough. Hours of sanding and perfecting the parts. Then fitting the neck. Total body time: 10-20 hours at least. That’s probably extremely conservative.

Components: hours of buffing and cleaning to get it ready to plate. I look like a chimney sweep when I’m done. All black gunk on your clothes and face. Carbon fiber and wood for back plates is incredibly time consuming. I hate that part. Probably about 15+ hours on metal. It is actually way more but I can’t even estimate it.

Finish: OMG! Don’t even know as they are all different in their challenges. Sanding, blisters on every finger, dying, sealing, spraying, UV oven, sand more, spray more, bla, bla. 30 hours easily total. The UV finish is so hard it takes 5+ hours of sanding and buffing alone. Then you go through somewhere. Do it again. I am now using Chromaclear for the top coat as it buffs much easier and looks fantastic. Still, it is very finicky on temperature and humidity whereas the UV polyester doesn’t care about any thing other than how hard it can make itself to buff.

Carbon Fiber- At least 4 hours of actual hands on work to saturate the fibers with epoxy. This is done twice to ensure saturation. Then it’s vacuum bagged for 10 hours each time. It sits for a few days on the form that makes it. Then you have to cover up with as much protective clothing as possible to keep the dreaded carbon fiber dust off of you and cut it with a grinder blade in the table saw. It is cut into strips that will go into the neck. Lots of carbon fiber in the necks all strategically placed. These are epoxied into the necks. Total time for carbon fiber. ???????? Lots of hideous time. Say 10 hours average.

That’s just some of the work. There are many more hours of total hand work doing the frets and setting it all up. CNC just makes deadly accurate parts and makes things possible that I couldn’t do other wise. It opens the doors to a lot of stuff that you just couldn’t do any other way. It definitely isn’t a cookie cutter thing like some people want you to believe. It makes things more time consuming in a lot of cases just because you know that you could do something with it so you do. Hope this helps.

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Let's not be so biased guys :D

I guess I am one of the minority of non-CNC builders here who does all of my work by hand (by which I mean I operate the tools directly with my hands as opposed to automating it with a computer). I do have a pantograph router that I built for roughing out the tops of my guitars which saves me a good amount of time but it does still need to be operated by me. I do build jigs to guide the tools I use and these are designed to be as universal as possible so that, for example, I can route the neck pocket for any size and taper neck into any body style of any thickness and at any angle all with the same jig. I cut my scarf joints on the headstocks with a japanese saw and true up the surfaces with a hand plane. It is very pleasing work to do and is quicker than setting up a table saw for the task (which is a good thing since I don't own one yet).

The main reason I choose to remain hand bulder is due to my personal approach to building guitars. I build my solidbody electric and hollowbody guitars using the same principles that I use to build my acoustics. Essentially tap tuning the bodies, necks, and tops to determine the best mix of tonewoods to fit the guitar I am building. To get the required tones out of these woods some tops need to be thicker or thinner in areas and some bodies may need to be voiced through chambering. While this may be easier to grasp in reference to an acoustic or hollowbody guitar I do the same with the maple topped solidbodies. The top carve can make a huge difference in the response and overall tonal balance of the guitar. Some maple tops ring like a bell and some don't. If there is a heavy bass response that is out of balance I may want to use the dampening qualities of the maple and make it thicker in the bass area (generally the area behind the bridge). On a hollowbody I may want to thin out the edges more to open up the treble. I haven't yet conceived of an approriate algorithm that would effectively produce these results that does not depend on my personal favorite feedback device: my ears.

Altering the top carve also affects the neck angle (or height above the body) and/or the bridge height so all of this has to be adjusted on an individual guitar basis. The adjustable jigs I use are very flexible to accommodate these design variations adn woudl be difficult at best to program in CAD. For what I want to achieve it would be a compromise build to dimensional tolerances when 1/8 of an inch can be too much when finding the resonant sweet spot through chambering.

Having said all that I could certianly make use of a CNC router if I had one. I would put it to good use by having it do the more repetitive routing tasks like those already mentioned by the other CNC builders. I use my duplicarver to rough carve my tops oversize so I can voice them by hand. There is no other way to achieve what I do. If I had a CNC I would also use it to rough carve the tops. It would replace my pickups routing jigs and my fret saw without a doubt. But I would never hand over the most important task of voicing a guitar to a machine that doesn't know the differnece between a resonant, sweet tone and plate distortion. Both qualities have their place when building for a specific tone but building to dimension does not account for the subtleties that occur in music. This is where the human machine is superior.

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Ours (DGM) are still 100% handmade! Our website will be completed soon and I will post links. Currently we are building a Bass out of some Beautiful wenge with a wenge neck and black hardware, wow this is killer grain, and a semi-hollow 8 string guitar out of 35 year old ash which will have a natural to red burst. The bass is nearing the final finishing and the guitar is approaching final sanding. If interested I can send pics. Thanks Terry D.

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Check out Ed Roman's take on CNC guitars in some other part of this forum. Then ignore everything he says. Twice, if possible.

Just found it. It's called "Why does everyone hate Ed Roman?"

I don't got the smarts to do that "link" thing or I would.

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hey, Dose anyone know if there is anyone with or has tried to make a completely Cnc setup? It seems quite feisable to me, if you had a tool changer and some custom tools for cutting bevels and for sanding I think you could do it.

Except for assembley and doing the paint job and other things like that you could automate most of the process. On second thought you could automate assembley and painting processes as well and have a completely computer-controled production line constantly producing guitars.

In the future everything will probably be done that way It's possible with today's technology so why not. :D

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Check out Ed Roman's take on CNC guitars in some other part of this forum. Then ignore everything he says. Twice, if possible.

Just found it. It's called "Why does everyone hate Ed Roman?"

I don't got the smarts to do that "link" thing or I would.

There's a lot of dimensioning, jointing, planing, gluing, bandsawing, sanding etc that a CNC can't do or isn't the best tool for the job.

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hey, Dose anyone know if there is anyone with or has tried to make a completely Cnc setup? It seems quite feisable to me, if you had a tool changer and some custom tools for cutting bevels and for sanding I think you could do it.

Except for assembley and doing the paint job and other things like that you could automate most of the process. On second thought you could automate assembley and painting processes as well and have a completely computer-controled production line constantly producing guitars.

In the future everything will probably be done that way It's possible with today's technology so why not. :D

I think Carvin has come about as close to this as anybody. Their free DVD shows one of their California Carve Top's being cut, sanded, routed, edged, carved, etc by a CNC machine. Even the screws holes for the cavity covers.

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I might be asking for something already answered :D anyway... Does any body knows about a CNC machinnig parts supplier? or in other words, any CNC router owner that can supply me custom bodies and necks?... Thanks! :D

Edited by jonbuho

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CNC stands for computer numerical control. Basically it is a router or mill that is driven by computer control. The process is very accurate and repeatable. It lends itself well to guitar production. Many big manufacturers are using this technology. Names like Gibson, Fender and PRS. There are also several smaller custom builders who use CNC machines as well. Ron Thorn is one who imediately comes to mind. Thorn does some truly beautiful work, check it out at:

http://www.thornguitars.com./customguitarh...stomguitars.htm

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I might be asking for something already answered :D anyway... Does any body knows about a CNC machinnig parts supplier? or in other words, any CNC router owner that can supply me custom bodies and necks?... Thanks! :D

There's a thread in Announcements and News by Jim Donahue. Check that out. It's pinned right at the top of the forum.

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I might be asking for something already answered :D anyway... Does any body knows about a CNC machinnig parts supplier? or in other words, any CNC router owner that can supply me custom bodies and necks?... Thanks! :D

I may be able to help you as well. PM me if you are interested.

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Some of those times seem a bit high to me. I am currently playing around with the machince here on campus for my Grad class and I have cut a couple templates, a guitar, and numerous other test runs in foam in addition to all the time spent on class work. The times ive experienced so far to perimeter a body in 2d in hard maple, 10 minutes and I could more then likely cut that time down. Currently I am working on a carved top bass and have set up some trial runs and to carve just the top it took roughly 17 minutes, yes all of 17 minutes. And to do a perimeter around that maybe another 2 or 3. It really doesnt take that long. The best part of use a cnc machine in my opinion is the safety factor. I am still not comfortable using a hand held router after 4 or so years of building, so ill stick to the cnc as long as I can which is until the end of May when I graduate.

MzI

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Some of those times seem a bit high to me. I am currently playing around with the machince here on campus for my Grad class and I have cut a couple templates, a guitar, and numerous other test runs in foam in addition to all the time spent on class work. The times ive experienced so far to perimeter a body in 2d in hard maple, 10 minutes and I could more then likely cut that time down. Currently I am working on a carved top bass and have set up some trial runs and to carve just the top it took roughly 17 minutes, yes all of 17 minutes. And to do a perimeter around that maybe another 2 or 3. It really doesnt take that long. The best part of use a cnc machine in my opinion is the safety factor. I am still not comfortable using a hand held router after 4 or so years of building, so ill stick to the cnc as long as I can which is until the end of May when I graduate.

MzI

knowing how much of a technical Geek Ron is ( sorry ron ..hahaa- Ron has actually built custom CNC just for kicks in the past) ...those estimates are probably very accurate down to the minute..at least for his guitars

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Well, I know that I'm just a lowly inlay guy, but here is my take on it.

I started inlaying all by hand. Did it that way for years. I've done some really cool work that way too. About two years ago I went to CNC and I would NEVER go back. I was really good before, but the accurancy of CNC has set my inlay into a whole other world. I can make very little, very complex pieces that would be almost impossible by hand and they fit perfect. Plus, once everything is done for the prototype, I can repeat the task with ease.

There is still a lot of hand work to do to finish the job, leveling, polishing, etc, but as I said I would NEVER go back.

I my opinion, there are two types of people - those who have CNC machines and those who can't afford it (yet).

A picture my my machine routing a fingerboard.

cam2.jpg

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Well, I know that I'm just a lowly inlay guy, but here is my take on it.

I started inlaying all by hand. Did it that way for years. I've done some really cool work that way too. About two years ago I went to CNC and I would NEVER go back. I was really good before, but the accurancy of CNC has set my inlay into a whole other world. I can make very little, very complex pieces that would be almost impossible by hand and they fit perfect. Plus, once everything is done for the prototype, I can repeat the task with ease.

There is still a lot of hand work to do to finish the job, leveling, polishing, etc, but as I said I would NEVER go back.

I my opinion, there are two types of people - those who have CNC machines and those who can't afford it (yet).

A picture my my machine routing a fingerboard.

%7Boption%7D

I totally agree. I'm all about handamade, but I would use CNC for certin tasks to make it more repeatable and better quility.

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Several years ago, I was a CNC operator at my job. Now, I just design stuff that winds up being cut on CNC equipment. In fact, the body of my first bass build was cut using this equipment. You can see the results on my website.

If I can be of help to any of you with questions, fire away.

I'm working towards my own machine in the next 18-24 months and will use it exclusively in my own building.

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