Which luthiers don't use CNC machines?

[bho]

Originally Posted by Alan Carruth

Dan Panther wrote:
"If you want similar characteristics between the same model guitar, you can achieve that with CNC. If you want a truly unique sound from your guitar, the handmade way will give you a more unique one of a kind sound."

Actually, I'd almost say it was the other way around. If you want to get consistent tone from a material as variable as wood, you need to be able to alter the dimensions of the parts according to some sort of 'feedback'. Good makers tend to come up with tests of flexibility or sound, such as 'tap tones' or simply flexing parts, that tell them how to work each piece of wood to get the tone they want. To my ear there is much more tonal variability in production instruments where all the parts are made to the same spec, regardless of the properties of the wood used. CNC, or other production techniques, are all about consistency of dimensions, 'fit and finish, and, especially, about getting those things with a minimum input of man-hours.

Now, it is certainly true that each hand maker tends to have 'their' sound, which may differ significantly from that of other makers of similar looking instruments.

Most makers work closer to the edge than factories do as well, in some respects. That is, factories tend to over build a bit, since they can't do the sort of testing that will tell them whether apiece of wood is a bit on the weaker side. A hand maker can take that into account, and come closer to the optimum dimension for any given piece.

None of this is to say that CNC doesn't have a valid place in making high end guitars. Wolfram Slides certainly got that right. It's good for getting dimensional consistency, and that's important in many respects, but it also has it's limits. The best results come from knowing which technology is appropriate in a given case. You also need the appropriate skill. I'm far more capable with hand tools than computer graphics: somebody with a different skill set will choose to do things differently than I would, but may get results that are as good.

This was a really interesting contribution to this discussion. It had not occurred to me that CNC'ing a part or series of parts could actually result in less consistency. But it makes sense.

[murrmac123]

Originally Posted by Howard Klepper

I will be giving a talk titled "What is a handmade guitar, and why should you care?" at the Fretboard Summit next month. This will not be a repeat of the usual stuff about factory vs. individual, and which is better, although I will give that a quick review.

For one thing, I will criticize the notion that the end result is all that matters.

I trust the organizers will have the sense to preserve this talk on video for the benefit of those unable to be present at the event.

[Silly Moustache]

Originally Posted by Wolfram Slides

CNC is very mis-understood. Most single luthiers who use CNC do it first for accuracy and repeatability, second for speed.

CNC makes perfect sense where wood is being shaped to specific dimensions (i.e. independently of the characteristics of the wood).

For example, slotting fingerboards. This is a job that requires absolute accuracy. Using CNC can enable a luthier to offer different scale lengths, fan frets with different configurations etc. much more easily. The properties of the ebony or whatever the fingerboard is made from make absolutely no difference to the placement of the frets, so a CNC'd fingerboard is indistinguishable from an accurately hand-cut fingerboard. This is probably the most common area that single luthiers make use of CNC - either their own machine, or outsourcing this work. I can't think of a single reason why a hand-cut fingerboard could be considered superior to a CNC-cut fingerboard.

Carving the bridge and neck are similar; as is cutting out the shape of the top and back of the guitar. Only the dimensions matter, and these are independent of the wood.

Where pure handwork does matter is in thicknessing the top and fine-carving the braces to voice the guitar. These are absolutely dependent on the characteristics of the individual pieces of wood. Currently, there's no good way for a CNC to adapt to the characteristics of the wood (though watch this space - I know a very well-respected luthier is researching this area, working on ways for machines to analyse the stiffness and acoustic response of the wood and control the CNC to thickness and shape each piece appropriately...).

I look at it this way - if I'm going to pay $X,000 for a guitar, I would rather that the luthier concentrated his time on the bits which really make a difference. If CNC can save his time from the mundane cutting and shaping tasks, the end result of which is indistinguishable, and enable him to spend more time on the bits which really do matter, then I'm all for it.

Cheers,
David

David, and Architype, seem to have summed this matter up for me.

CNC is all about repeated accuracy for high volume products.

Therefore there is little point in someone producing just a few items annually in having (and paying someone to programme and maintain a £50k plus machine) unless a few thousand items are to be produced.

Collings uses CNC for their necks. What I can't understand is that despite this, their neck shapes and dimensions vary considerably, and after I proved that - they now declare on their website that they will vary.

[GaultierRedon14]

According to his website, Mario Beauregard doesn't use CNC's or jigs.

[gitarro]

I would think that CNC can be used on inlays without any tonal issues...

[Schau_ins_Regal]

Originally Posted by Silly Moustache

Therefore there is little point in someone producing just a few items annually in having (and paying someone to programme and maintain a £50k plus machine) unless a few thousand items are to be produced.

You seem to have no idea of the CNC market. There are machines available starting from maybe £2-3k that are usable for lutherie.

[Zissou Intern]

Eastman...

[mc1]

Originally Posted by Howard Klepper

I will be giving a talk titled "What is a handmade guitar, and why should you care?" at the Fretboard Summit next month. This will not be a repeat of the usual stuff about factory vs. individual, and which is better, although I will give that a quick review.

...

sounds pretty interesting. feel free to use my graphic.

[Mr. Scott]

Originally Posted by Zissou Intern

Eastman...

I was just going to mention these. Rumour has it that they build everything by hand and nothing is machined. I recently watched something on Youtube where the US representative of Eastman said catagorically that the company did not uses CNC production "at the moment." Does anybody know whether they have started to use CNC now and if they have, when they started?

[MrHooligan73]

Originally Posted by Schau_ins_Regal

You seem to have no idea of the CNC market. There are machines available starting from maybe £2-3k that are usable for lutherie.

When our company purchased new CNC machines about 7 years back the old 3 axis ones got auctioned in house to employees. Noone paid over $1000 for one. It is very possible to get them very cheap. They all worked fine.
Hint.....
Find a factory closing down and make them offers and pay to move it yourself. Save a ton of money.

[Bruce Sexauer]

Originally Posted by mc1

Thank you! It am guessing ten thousand of these would be identical?

[Silly Moustache]

Originally Posted by Schau_ins_Regal

You seem to have no idea of the CNC market. There are machines available starting from maybe £2-3k that are usable for lutherie.

A rather arrogant and impolite statement - but accurate.
The only CNC users I have witnessed, were, I was told, the sort of figures that I mentioned.
Apparently there are simpler CNC machines available.

Nevertheless, I believe that my point remains valid - for a maker/manufacturer to invest in such a tool, requires careful consideration of the time savings vs investment.
.

[justonwo]

My sense is that most luthiers don't use them, but I could be wrong. Most of the time, I'm seeing luthiers use them to rough out neck blanks when they do use them.

[Wolfram]

Repeated accuracy at high volume is just one use for CNC. Though just because Collings or any other builder uses CNC for their necks does not mean that they are all made the same - though they certainly could be.

I have a small German CNC machine that I built myself from a kit (total cost with spindle, tools and vacuum workholding was about £3k). I use it for product development, one-off or short-run prototypes, and small production runs. Granted I don't make guitars (though my machine is quite capable of cutting all the components of an acoustic guitar), but I actually like to use CNC as much as possible when developing a product, because as I make small changes they are fully and accurately documented as a series of 3D CAD models so when I go to make production tooling I know that they have accurate documentation to work from. CNC programming requires all the same thought processes, care and attention as handmaking a product - it's just directed differently. It's definitely not a case of throw in some wood, hit a button and a guitar neck pops out the other side!

I recently collaborated with a guitar designer to put a new design into mass production, and for some components we only had handmade prototypes to work from, and were unable to achieve the accuracy and consistency we required when scaling up. We used 3D scanning technology to reverse-engineer those components, and drove a CNC directly from those files to make the tooling we needed. Problem solved!

I believe getting the balance between automation and handwork is the key to a great product at the most economical price. I make my cores of my stainless steel guitar slides on a huge £150,000 CNC lathe, and achieve tolerences of +/- 0.05mm or better on the dimensions. But every slide is then finished and polished by hand - this ensures that the surface is mirror-perfect. I don't know how to achieve that finish to the quality I require with a machine - I need every one to be perfect.

Another example: Anyone who bought a Wolfram Precision : Crystal nail file prior to March this year, the paper and foam inserts were cut on my small CNC at home. Once we hit large enough volumes, I had dies made from the very same CAD files I was using to drive the CNC knowing that they would cut exactly the same packaging that I had perfected on the CNC (...obviously with the proviso that the dies were made accurately!).

There's no reason that all of Collings necks need to be the same profile or dimensions (I know for example that they offer both 1 3/4" and 1 11/16" nut widths) - they may have several that they use. Remember that CNC will probably be used to obtain the rough carve of the neck - it will likely be finished and sanded by hand, which will introduce irregularities too.

So, yes, great guitars can be made completely by hand. But I really don't think the use of CNC devalues a guitar in any way, as long as the end result sounds, feels and looks good - that's what matters. I own some great guitars, some of which were completely handmade, some with CNC input. Interestingly, my most 'custom' guitar, a complete one-off fan-fret with many unique construction features including a wider saddle than usual, utilised CNC widely alongside traditional build techniques and voicing (as you can see from the photos in my AGF build thread). The guitar is exquisite in every way!

Cheers,
David

[Ryler]

Originally Posted by mc1

I scrolled by your name without noticing, saw the graphic, laughed, and scrolled back up to verify that it must be you. mc1, you have a style.