CNC vs. all handmade

Hey Tom

ummm I think you were misinformed about Driskill as he does in fact use CNC machines. Off the top of my head, McNaughts are the only ones I know of that are strictly done all by hand, no cnc work anywhere on the guitar.

I, also like you, could care less if it was made by hand or by machine as I think it has very little to do with the quality of the instrument in question, if anything the CNC'd machine would be a better build as its much more precise. I think it has a lot more to do with the builder in question and his attention to detail than anything else. More his love for building instruments is what adds the mojo to the 6 string monsters.

 

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

"Powered by HAAS...and loving it "

 

There you go.

Ron himself posted here.Bitchin'. That cat makes great guitars.

 

WOW!!! Ron thanks a bunch for breaking down the CNC - Hand process for us. THat is the first time I have ever seen it all spelled out as to exactly what is done by the CNC vice hand. I just cant imagine trying to build all the jigs and what not to do it all by hand with routers and such and how on earth it could be accurate.

 

Holy crap!

First of all, that's a hell of a post Ron. It puts the whole argument into perspective. Having toured through Fender, including the Custom Shop and the regular shop floor, as well as a few tours through PRS, you learn what Ron just said works on a bigger scale. The CNCs run non-stop in those places, but they don't have very many. What really speeds those places along is the literally dozens and dozens of other workers doing all the hand work as mentioned above, just assembly line style. One guy does one grit sanding all day. One guy does radius sanding for the fretboard all day, etc. That's how they get so many guitars out. The CNC just makes the parts fit better and with less waste and trial fittings.

The big difference in operations of the small vs. big builder, is the small guy starts with talking to the customer about what he wants and goes from wood selection to final polish of the instrument before it goes in the case, where the big guys end up with each person being really good at one given task but it never has the benefits from the one one one approach. You also end up with looser tolerances overall and customization is minimal to none.

Second of all, take that hourly estimate Ron gives and divide it into the base price of one of Ron's Artisan Master guitars (the most expensive). The dude's making less than $50 an hour, and that doesn't include any material costs or company overhead at all. I figure if you take those into account, the guy's lucky if he's making $20. That's nuts.
It's also why I think Ron's guitars are a steal, but it really makes you appreciate any small builder. None of these small guys are getting rich building guitars, no matter how they do it. They do it because they love it.

I find it inspiring.

-e.

 

Ron, not doubting you, just curious. On my last tour of the PRS factory, I saw their CNC carve a body from a block of wood. It was scary how fast the process went, my memory is fuzzy but I'm thinking under a few minutes, not 3 hours. That carver moved so fast, with chips and sawdust flying out all over the place, it was amazing, really. We could see the whole process because the panels around the body were either glass or some sort of plexiglass.

Is the difference in time between PRS's body carving and yours a function of PRS simply have millions more dollars to spend on the latest robotics or are other factors involved?

 

We just purchased our first CNC machine....also a HAAS.....We have been using an early seventies Rockwell Pin router.

The reasons for us to purchase a CNC:

-Accuracy...on the pin router we use plexi glass templates which have bit of wear, plus they just aren't perfect....we want everything to line up and fit perfect.
-Waste...currently we are building 6 guitars a week...when you are building the necks and body completely by hand like we are you lose one every 2 weeks do to some misfortune.
-I want my employees to focus on the details...fretwork,sanding, finishing, fretboard radiusing, set up.

Right now we are just using the CNC machine to cut all of the cavities..( neck pockets, pickup cavaties, control cavaties)....we are also cutting the bodies out...but they go back on the pin router for the carves....We are also cutting the neck profile, truss rod channel, and rough cutting the back carve also....but then we have to finish the neck with our good ole spoke shavers and rasps.

Currently we have a back log of about 125 guitars....so we felt that purchasing a CNC will help us keep a grip on quality control as we continue to grow.

 

Personally, I've never been under the impression that a CNC was a bad thing; it is just a tool to do some early or mid-level work. I think maybe there is the perception that guitars pop out of these things ready for final assembly and painting.

I'm sure the builders on Tom's original list who use CNCs do so much like Ron's excellent breakdown of hand vs CNC work - Anderson, Suhr, and Grosh all use CNCs in this manner but rely on their artisans for the hand finishing work. It's getting easier to say who doesn't use CNC than who does. I'm not sure about Lentz, but Terry McInturff was still using a duplicarver last I heard and hadn't moved to CNC.

Of course G&L just very publically announce they bought CNC routers, and I believe I saw somewhere that James Tyler just got his first CNC this year as well.

 

Sorry to disappoint you Tom, but we use a CNC as much as we possibly can. We don't own one (yet), but we have access to two of them and I have a feeling that we'll own one of our own before too much longer.

I don't think of us as a custom shop at all and it's certainly not what we set out to be. We do take some custom orders, but my preference is for us to build guitars to our specs and either sell them either once they're well underway or even better, after they're complete.

 

Of the boutique bass makers, the only (major) ones I know about that are completely hand-made are Elrick and Eshenbaugh...

As a guitar player of extremely picky tastes, it doesn't matter to me if a neck is farmed out to another solar system, as long as it plays flawlessly

I was thinking the other day, a few of the guitar makers that we'll all be flipping out about 15 years from now will be built by people we've not yet heard of, or who have just begun being apprentices somewhere today

we're in the golden age of guitar making...

I apologize if I got a little off-topic there

 

Again.

 

Ron Thorn wrote:
>>Can I build a guitar without 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.<<

That, right there, answers the CNC question for me about as definitively as possible.

Eric wrote:
>>I figure if you take those into account, the guy's lucky if he's making $20.

Hey, don't remind him!

Jon wrote:
>>It was scary how fast the process went, my memory is fuzzy but I'm thinking under a few minutes, not 3 hours.

Jon, I was just on a tour and asked that very question. "About 20 minutes" was the answer for the bodies. The necks take longer because there are multiple setups and passes.

The PRS CNC machines automatically exchange router heads on the fly, so they are able to do an extraordinary amount of work in one pass. I don't know if the CNC's at other shops have that capability. If not, it would slow things down quite a bit, I'd imagine.

 

Jon,
Under a few minutes is probably pushing it. I know PRS' spindle speen is 10K rpm, mine is a little less so my feed rate is slightly lower. I have a few more operations to do such as top and side purfling. There is probably three main reasons I'm slower:
1 - Every body is different. It's not a case of load the body and walk away with mine. I'm currently up to 29 rear cavities, so I load the appropriate one and once it's finished I load the next program. Pickup combos, different body thicknesses, etc.

2 - I don't push the machine very hard. It takes 45 minutes to do the carve top. I could probably push it to 30 minutes, but risk blowing out some maple...not worth it. I haven't had to run a body through the bandsaw before it hits the dumpster yet, knock on wood.
Master Builder Red Dave from the Custom Shop always busts my chops when he sees me running a body. I'll take 4 passes around the perimeter and a final clean-up pass...at Fender: 1 pass, done.

3 - I'm still chicken-sh*t. When you find just the right top for the customer, that he selected, the last thing you want to do is rout for a humbucker where a P-90 should be. I'm standing in front of the CNC the whole time it's running making sure everything is "cool". My heart still races a bit when a body is running...I'm not afraid to admit it. 20hp can do a lot of damage to wood .

PRS needs to pump out as many as possible per day. They've probably refined their programs to optimize every second of run time, they need to. I'll take it a little slower just to be safe.

Ron

 

I'm here to tell you brothers and sisters that all those evil computerized, whizzing and whirring machines are the Devil's tools!! Throw a bunch of wood, store-bought plastic, screws and paint in one end and out pops a completed, machine-made guitar on the other end!!! What kind of evil-black witchery could concieve of such a foul and inhuman plot ? It's Satan's work I tell ye!

No, give me a hand-made guitar! You'll sleep much better knowing that a trained luthier used his olden slide rule and fingernails to carve the neck and slot the fretboard! And that our luthier hauled only the purest sand in a wheelbarrow up from the shores of Gichegoomee for the hand-made sandpaper that was employed. And that he himself slaughtered the horses whose hoofs were used to make the glue and that he forged and milled all the screws himself to exacting detail and that he used his very own, hand-made chemical plant to produce the plastic and the injection molds used to create the knobs, pickup rings and control cavity covers. This kind of quality cannot be matched by an eeevyul machine, conceived in the mind of Satan's goat-boy, Bill Gates!

:angel

 

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.

 

We can now see that they don't call those Driskills Diablos without good cause! Repent I tell you! Repent!!!

 

From their live LP "Satan's in my HAAS"