Inconsistencies in Gibson Guitars: How & why

[Archie]

*These are my opinions based on my own experiences in guitar component manufacturing. There is room here for error and misunderstanding*

In response to another post, I wrote about how on receipt of a Gibson Byrdland, I noticed there were flat areas on the carved plates. Due to my increased knowledge of guitar component manufacturing and my understanding of how Gibson branded guitars are manufactured, I thought I would explain how and why these issues (defects?) occur. The potential for and subsequent presence of these inconsistencies, are baked into the DNA of the Gibson brand and follows one company to the next, starting back in the 1950’s.

My aim here is not to pick on the Gibson brand and all manufacturing comapines will have short comings to some degree, especially those in the mass produced 'luxury brand' category. A category that straddles the difficult line between luxury bespoke manufacturing and mass production.

Problems and challenges in manufacturing are varied but the Gibson brand carries with it the added weight of ‘Heritage’. Heritage shouldn't factor into a modern manufacturing operation but it keeps getting dragged in. This is born out when Lee Anderton of ‘Andertons’ seems entirely consumed with the ‘Gibson Custom Shop' being historically accurate. He starts pointing at pots and sanding machines that are clearly modern, saying “they must have been here forever”, when in fact the very facility he is in, has been used to manufacture Gibson branded guitars for 30 years. This heritage that weighs around the neck of the Gibson brand, is also its main attraction.

Here I will give examples of what goes on and how these ‘heritage’ and business factors, lead to the introduction of inconsistency. It is worth noting that imo many Gibson lovers enjoy Gibson branded guitars because of these inconsistencies. I maybe mistaken but I believe these inconstancies are what buyers and players misidentify as ‘soul’. You will often hear people complain that Japanese guitars have no soul. This could be down to finish, colour, or it could be that they are so consistent, that they appear to lack personality. The more rational art becomes, the less soul it is perceived to have but then, I love rational art.



Manufacturers of Gibson branded guitars (currently KKR &Co) use ‘hand finishing’ on necks and bodies for their USA range. It seems they primarily do this to address excess binding and material left by a roughing CNC operation. A 4 axis CNC machine (which they use in the custom shop), can finish a neck to exacting dimensions but they use a 2.5 axis machine at USA. By using a less advanced method to carve the neck, they then use a belt sander to finish the operation. This is the reason why Gibson necks can be inconstant between models and years. Using this type of belt sander introduces a high level of risk and with risk, comes error.

Solution: Use a 4 axis CNC and finish by hand sanding.
Drawback: This would significantly increase time and outlay.

In the below video, Joe (the foreman) is correct in that a "CNC makes great guitar parts" but he's saying "people make great guitars" to cover up the fact that they are using inconsistent and cheaper methods to make something that a CNC can do far more consistently. This then becomes a question of business and what they are prepared to invest v:s what they get out/return.
In this case, it’s simply cheaper faster and more reliable, for them to take the risk.
To add a little more context, that sander would likely sand through that entire neck piece in under a minute. The sanding will also heat the wood and then has potential to create conditions for malformation. It's very much a hammer to crack a nut but it doe two operations at once to a somewhat adequate degree. I think it actually does a better job of removing access binding than it does shaping the wood to a consistent dimension.

22:20 “here we hand roll necks”

Another example of the inconsistency built into KKR & Co’s operations is the finishing of carved plates. This is another questionable long term practice used by serval past owners dating back to the 50’s.
As stated above, having recently purchased a wonderful sounding and playing Byrdland from the early 2010’s, I was surprised to see flat areas on the surface of the carved plates. I suspected this had been done by the use of a pad sander. Imo this is again an example of the wrong tool for the job. Corner cutting here creates the need for inaccurate operations down the line. As with the belt sander, a pad sander kills two problems at once. You can reduce the binding and remove tool marks. Neither job gets done well; we’ve all experienced over rounded binding and those who have looked close enough (or looked at all) can witness deformities in the finished plates.
In the below video an astute rep seems concerned about the pad sanders use. The machine offers a very high level of risk that hand sanding and improved CNC machining wouldn’t. Again the higher the risk, the more mistakes. In both cases however, Joe and others perceive this risk as a sign of quality and skill, when in fact it is the other way round.

3:40

In the below video focusing on 'Custom Shop' factory (I think it is a Byrdland that the worker is sanding) they are using the same sledge hammer (pad sander) on delicate spruce and larger carved plates (more room for error). This is the reason why my Byrldland's carved plates have flat areas.

11:45

Solution: Improve finishing passes in CAM then hand finish plate with a soft pad. Add binding before CNC cutting.
Drawback: More time consuming, greater ware on tooling/cutters.

It's easy to say “use more CNC” until they need servicing, develop faults, software issues etc..There are always better methods but whether they are practical given the demands on the company, is unknown to me. I would chuck out the pad sander from the custom shop and improve the CAM operations. Again easier said than done.

This then speaks to a now glaring and unaddressed question. I 3D scanned and took plate thickness readings of my Brydland and the results where almost incomprehensible. The plate around the F-holes is thinner likely due to the pad sander focusing on the binding, therefore not entirely an indication of the plates desired thickness, as often assumed. The top under the bridge was slightly thinner than just behind it when it should be the other way round. This is likely due to the highest point on the plate getting more attention as the pad passes back and forth from side to side. Each plate will therefore be different but in a way that is arbitrary.

This is what I would expect to see in mass produced plates from 1950’s and given the use of the same ‘heritage’ tooling and processing from that era, it's not surprising. The introduction of advanced CNC operations has done precisely nothing.

If fellow manufactures from the industry, or other woodworking industries would like to chime in, I'd be interested to hear your thoughts.

[Rickco]

Problem is ,when everything comes out predictably perfect from automated process's and theyre all the same we'll have nothing to talk about

[jads57]

I think in the 1950’s and 60’s as well as before. Even though they had jigsaw and molds, they was way more dependency on hand work and tooling. Which meant having more individual feels an inconsistency from guitar to guitar.
While I can see that in solid and Thinlines Gibson are way more consistent to each other nowadays.

But in a hand carved Archtop, I would think still needs way more attention to the woods being carved. But if the wood was fairly stable and similar,maybe not? And could use CNC to do the carving?

[bluejaybill]

It sounds to me that you are assuming that CNC will ideally, give you the perfect neck. And that hand work, by its very nature, is inferior.

I have not yet played a CNC neck that I think is as comfortable to play as ones that were made by artisan's hands, such as my Campellone and Borys, as well as my vintage Fenders and Martins.

I keep a '97 R8 Les Paul around here for its usable sounds, but it is far from a comfortable guitar to play.

Maybe the new CNC is better. My money is still on folks that have learned the craft well and are very used to applying it consistently.

[Marty Grass]

Often the trouble is that we don't have CNC made hands and minds, mostly the latter.

I have seen very good guitarists being less finicky than some not so good ones. Many can easily transition scale lengths, string gauges, and body types with only a few minutes of time to adjust. I'm not one of them. But I do think there is sometimes a little bit too much whine with our playing.

[wolflen]

Let's wake up that old "saw horse"...

"Well..they don't make 'em like they used to..."

[SOLR]

Of the few things that got to me in the linked YTs, one was how many times Jim DeCola got his hands/fingers so close to some of the "lethal " tools .

The other was seeing all those workers perform these endlessly tedious and repetitive tasks, some looked downright hazardous (health wise).

I unfortunately can't offer any valid opinion to Archie's conundrum, other than it's possibly these inconsistencies that make up for your "wonderful sounding and playing Byrdland from the early 2010’s".

Interesting thread .


S

[Archie]

Problem is ,when everything comes out predictably perfect from automated process's and theyre all the same we'll have nothing to talk about

I think the design is the most important part. What comes out the other end is a product of process. Very few manufacturing companies want the end result to be randomised.
When it comes to custom manufacturing, getting what the customer wants, through the application of correct design and then delivering that, through the correct process, is the pinnacle of bespoke manufacturing. I would then argue that through automation, can come ultimate freedom.

[Archie]

I think in the 1950’s and 60’s as well as before. Even though they had jigsaw and molds, they was way more dependency on hand work and tooling. Which meant having more individual feels an inconsistency from guitar to guitar.
While I can see that in solid and Thinlines Gibson are way more consistent to each other nowadays.

But in a hand carved Archtop, I would think still needs way more attention to the woods being carved. But if the wood was fairly stable and similar,maybe not? And could use CNC to do the carving?

Manufacturing and luthier'y are two different fields. KKR is not a luthier'y company, they are a manufacturing business. They have diverging interests.

Luthiers can benefit from manufacturing, if they for example create a ‘signature’ model for an artist. Then your aim is to try and reproduce an existing guitar (much like KKR do) and therefore what you want is consistency. Sadowski went down this route with Jim Hall. This works well with laminate guitars.

With carved models, the best thing you can do is what has been done by the likes of Norlin, where you over brace a carved top plate and make the upper bout portion of the plate so thick, that there is almost no variation in the tone between spruce plates. Then you just have to reproduce the shape in order to get the same setup (height of plate etc..) and look.

With luthier made carved guitars, you can use CNC to get you 0.5mm off your desired shape, from which you can then brace and voice. There is a place for CNC machining in luthier carved plates imo and that’s something i’m going to explore. Whether it is the braces being carved out instead of glued in, whether it is the precise thinning and geometric shape that allows for a thinner stronger plate (this is more down to CAD design), all of that can be explored.

[Oscar67]

Personally I think the OP is spot-on. However such considerations will never sway guitarists who are looking for that one special guitar. Buying a guitar is not like buying a hammer, it’s like buying a painting. Folks want to _feel_ something, a bond with the chosen item, and especially they want to feel the sensation of having found “a really good one”. Lots of guitarists are convinced their stuff is special somehow. Of course objectively it’s not special at all, but emotionally it can be.

As the OP points out, consistency is often associated with clinical, soulless, cold, etc. That’s one of the reasons PRS is disliked so much.

[jads57]

I noticed some years back playing many of the same model Gibsons at Dave’s Guitar Lacrosse,Wisconsin. There was a 5% to 10% difference in all of the various models from Historic Les Pauls,335’s,etc.

Mostly in weight,and the guitars resonance factors. I would attribute this to CNC machines and wood selection being the main factors.
I will say whether real or preconceived, the PRS guitars seemed a bit more soulless imo.
And I have owned a number of both newer and older guitars from both companies

[Gitterbug]

I hear a lot of skepticism towards CNC milling. Why? With enough axis dimensions, what you feed into it - by way of programming and woods - is what you get, with precision and consistency. I've understood that Mark Campellone uses CNC, but don't know to what extent. On carved tops, what makes CNC worse than hand-drilling a pattern of holes à la Bob Benedetto? The OP focuses on Gibson; what about Fender, for example? I just don't understand why Gibson retains age-old machinery in the US where labor is relatively expensive but has invested in more recent technology in the Far East where labor is cheap.

[2bornot2bop]

Often the trouble is that we don't have CNC made hands and minds, mostly the latter.

I have seen very good guitarists being less finicky than some not so good ones. Many can easily transition scale lengths, string gauges, and body types with only a few minutes of time to adjust. I'm not one of them. But I do think there is sometimes a little bit too much whine with our playing.

and for some of us it never occurs to us to think about those things. It’s simply see guitar, play guitar. A piano player’s perspective. Perhaps that’s the joy of not knowing what you don’t know.

[ccroft]

If CNC was available to Gibson in 1950 they would've used it for plate carving instead of 'The Green Monster' duplicate carving machine.

I don't know if Mark C is still using one, but he used to use a duplicator for the rough out.

A better tool is a better tool. Simple as that. Is there some problem with consistency that I'm not seeing? Why does it matter if it's electricity or meat power that's pushing the cutter?

Thanks for your in depth analysis Archie! All makes sense to me. And there's the added human factor of illness, boredom or too many beers last night to add to the equation.

I'm a woodshop foreman for 30 years and guitar player for 55. Never had the balls to try and make one :)

[deacon Mark]

CNC is fine and probably better for solidbody guitars. For a fully acoustic guitar the final workings for sound are best done by a person most especially the maker. In the case of Gibson they need to have someone doing that who knows what they are doing. My understanding is the Paul Reed Smith guitars are CNC to the max and that tolerances are quite fine and detailed so that everything comes out the same. I like PRS guitars for sure, but I have to say they don't seem to have quite the bend in my ear as a Les Paul. I would rather have a LP for sure.

One can understand and get it that CNC is the best thing but maybe in the end under the right set of hands and eyes they are not. In the case of fine carved arctops and really flattops too I will take one the has been gone over by someone who really has an understanding of wood. To me it is like using AI. AI if fine but one has to remember where AI gets its information. AI can be wrong just like regular luthiers. Once a guitar is out in circulation and being played and gigged then it begins it life and will not the be same as another like guitar because of environment. Some players have sweaty hands, some play hard, some only play with a light touch, all these will change a guitar as much as the manufacturing once out. Also, the climate has a huge effect.

[SOLR]

Humm! some of the threads remind me of the still ongoing Analog vs Digital debate.

S

[Rickco]

I think were talking about a couple different things, having spent over 50yrs in wood and wood products manufacturing (never made instruments) If were talking about guitars meant to be amplified, solid, semi hollow etc I believe a CNC shop could produce consistent high quality production guitars as seen from many lower cost Asian manufacturers. If were talking about a truly acoustic instrument theres no reason ruff in couldnt be CNC or multi head shapers but...to make it a truly fine playing and sounding (archtop for instance) will require an experienced luthier with the hand skills, ears and materials to voice it. I think the neck is an interesting example, very personal, who decides every neck should be X shape? how do you know until you play it? What would the marketing guys say? Recently I went to GC looking for a cheap bass. Everything in there was playable and frankly better than the low cost instruments of my early days. Funny thing is here was a case of theres been nothing made since my early '60s JBass thats improved or as good but could probably be knocked out in minutes in the modern Fender shop and we'd never know the difference. However an acoustic only bass git of high quality would require the aforementioned luthier and big $$$. Per the OPs point, consistency would be improved with automation but quality in an instrument to a large degree is personal, my buddie thinks his Kay is as good as a D'Angelico... obviously it is.

[Archie]

Personally I think the OP is spot-on. However such considerations will never sway guitarists who are looking for that one special guitar. Buying a guitar is not like buying a hammer, it’s like buying a painting. Folks want to _feel_ something, a bond with the chosen item, and especially they want to feel the sensation of having found “a really good one”. Lots of guitarists are convinced their stuff is special somehow. Of course objectively it’s not special at all, but emotionally it can be.

As the OP points out, consistency is often associated with clinical, soulless, cold, etc. That’s one of the reasons PRS is disliked so much.

Well put.

[skiboyny]

No two guitars are the same regardless of how stringent the specs are held too. It's the wood, that sounds a little different. This even applies to plywood. You can take the most precision built instruments and although they will have the same personality, the wood will make them a little different. I have proven this to myself over and over.

[ccroft]

No two guitars are the same regardless of how stringent the specs are held too. It's the wood, that sounds a little different. This even applies to plywood. You can take the most precision built instruments and although they will have the same personality, the wood will make them a little different. I have proven this to myself over and over.

This is why I would agree with the good Deacon that you need someone who understands both wood and how guitars work for the final passes. Especially the instruments we typically play.

Off CNC and on to what Archie thinks may have caused the flat spots on his Birdie: sanding. First time I saw a video of a Gibson guy using a stroke-sander to both flush the bindings and take out machine marks in the top I was blown away. It's a very aggressive tool! There's gonna be on days and off days. If you catch a belt edge you're gonna go back and fair it out a bit. And slightly change what was the intended shape of the thing. You're not going to QC and say "Damn... I messed up another L5."

The luthiers I know use hand scraper and then hand sand. The only reason to do it as Gibson does is production. It's way way faster.

That's what I like about what I know of Mark C's approach. It's a blend of modern and traditional hand tool methods.

[Archie]

No two guitars are the same regardless of how stringent the specs are held too. It's the wood, that sounds a little different. This even applies to plywood. You can take the most precision built instruments and although they will have the same personality, the wood will make them a little different. I have proven this to myself over and over.

Whilst true, the point is to do with manufacturing process and consistency in modern instrument production.

I agree that without the same input, you cannot expect to get the same output. That being said, there is always room to strive. Next year I’ll make two identical laminate bodies. We’ll test them to see how close they sound. We’ll go through the process together.

[skiboyny]

Whilst true, the point is to do with manufacturing process and consistency in modern instrument production.

I agree that without the same input, you cannot expect to get the same output. That being said, there is always room to strive. Next year I’ll make two identical laminate bodies. We’ll test them to see how close they sound. We’ll go through the process together.

That would be a great experiment but the wood would have to be from different batches. I think much of the variance in like models comes from the different batches of woods purchesed through the years along, with slight differences in the manufacturing process. Whether it's human or machine, tolerances must change slightly.

[spencer096]

Manufacturing and luthier'y are two different fields. KKR is not a luthier'y company, they are a manufacturing business.

...this aint right.

[John A.]

Manufacturing and luthier'y are two different fields. KKR is not a luthier'y company, they are a manufacturing business. They have diverging interests.

No, KKR is a finance company. Their business is buying undervalued businesses, cleansing them of bad assets and debts, and then selling them. I think you have to view any PR they broadcast through that lens. Those videos are just making lemonade out of lemons by calling the past owners' shortsightedness in technology investments a visionary hybrid of modern and traditional guitar-building; they're aimed at potential buyers of Gibson the company, not at buyers of Gibson guitars. Of course it's possible to have CNC equipment that machines the wood more precisely and gets close enough to final dimensions so as not to need that sort of aggressive sanding. But that would take investment in newer/better CAD and CAM, which KKR is not going to do.

[Rickco]

Archie is actually going to do this comparison of the bodies. Looking forward to that. What percentage of the sound is the body as compared to the neck the strings the action the player the pick (or not) the room the temp not to mention I think the OP was referring to a carved top guitar which as has been said could be ruffed out by machine but must be voiced by hand and experience of the maker. A carved instrument is completely different thats why guys like MC and BT are busy and respected. I dont believe any machine will duplicate what a luthier can do on a carved guitar. Where automation could come in is on a pressed top guitar (solid woods) where consistency of outcome could be more predictable. Peerless made some exceptional guitars of that construction and Gibson blew it with shit marketing and ridiculous prices. Personally I wouldnt want a "perfect" cnc carved archtop, I respect the hand work and its variations, its what you cant see that really makes the difference.