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I’m starting my first guitar. Have the neck blank near complete and now starting to think about the body. I have Cumpianos book and he uses a work board instead of a mold and radius dish. I already have a mold that I built a few months ago but do not have a radius dish yet. So now I’m debating, should I build 2 radius dishes (15’ and 28’ seem to be the norm) or should I forget about the mold and build a work board instead. Seems like the work board method would be more difficult to get the side radius to match without the aid of a radius dish. But like I said, first guitar so looking for some advice.

You *might* be able to kill two birds with one of these:

https://www.canadianluthiersupply.com/c ... work-board

I have both 30’ and 15’ work boards from them and also 30’ and 15’ dishes.

I think the thing that the work board would hinder is maybe driving the bus (putting the radius on the rims).

Worth considering though. As a radiused work board they are awesome.

Brad


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One of the first guitars I made many moons ago was with a mold and not using a radius dish. All kinds of options. I build open face now. Pick something and stick to it.

If you already have the mold, you will probably find it easier to do your first build by that method. It really helps with keeping the sides straight and the neck and end blocks perpendicular to the bench.

You can sand the radius onto the rims without a radius dish if you use a sanding stick. This is basically a piece of 4x2, or something similar, long enough to span the length of the guitar body. You glue coarse grit sandpaper on one end, and a slight wedge at the other end. When you lay this on the rim of the guitar body the wedge means that the end with the sandpaper is making contact a few degrees off dead flat (angled outwards). You just work your way around the full circumference and you will achieve the necessary profile. I make it flat in the upper bout of the soundboad and radiused for the rest of the top, and all of the back (different angle for the back). I find this easier than "driving the bus" with the whole thing in a dish (that is really hard work). In truth, the radius of the soundboard is so slight that you can get away with the rims being flat on that side.

A radius dish is still very useful for shaping the bracing and gluing them in a go-bar deck

Yep. I still use the Cumpiano book method of gluing braces one at a time using cam clamps and a flexible backing slat, but it is definitely more time consuming than go-bars and radius dish. I do it because my workspace is tiny, so molds/dishes/go-bar deck/etc. would be in the way all the time. Cam clamps are small and versatile, so they're perfect for my needs. I also do all the assembly without any workboards or anything.

It's really a matter of personal preference more than anything. Although some builders use a heavy cylindrical radius on the soundboard, and for that you pretty much have to use a mold and dish.

I use a 15' radius beam/bar/stick for backs and a 28' for tops. After 8 guitars in 5 years I find that it works so well I won't go to dishes and go-bar decks. Just as easy to sand with the beam, and only takes a little longer to glue braces against it. If you build a bunch of instruments or you love to make tooling, dishes and decks are probably a good idea.

Ed

We were taught the Fox style adjustable mold when I took his course many years ago and I stuck with it. There are some advantages and disadvantages over a fixed mold but I use a radius dish with both.
I do use a fixed mold for archtops.



I think the advantages of radius dish aided construction with a mold and go bars, at least to me, are many and I would have no reservations recommending that approach. I think I would also recommend using a fixed rather than adjustable mold if you are just starting out. It is a much more conventional approach.

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Traditionally classical guitars with Spanish heel necks are build on a workboard, most steel string guitars with separate necks are built in a mold. As you know, Cupiano builds one of each. With an external mold you can either use a radius dish or make some radiused cauls for clamping your braces on.

My second guitar was a classical and I built it in a combination of work board plus an outside mold - did a little futzing to get the mold to fit around the heel but it worked and kept the rims in alignment with the top.





I built radiused clamping cauls for my first couple of builds but decided that radius dishes made more sense and broke down around number 3 or 4. All of my steel string guitars have been built in an outside mold - when I make it I use the inside cutouts for my bending mold.

I kinda get what your saying and this method sounds good to me. Are there any instructional videos on this that anyone knows of. Searched you tube but all I can find is sanding with a radius dish.

I like the looks of this method. Wasn’t really looking forward to making radius dishes anyway and I’m not in a hurry to clamp every brace at once. Just wish I could watch a vid on this method to see the basics of the operation.

Here's a link to using the late Ken Cierpilowski's Mega Mold which has a radius sanding beam mounted on a shaft with a tilting base/table. I built one from looking at pictures and it works just fine but I went back to radius dishes and fixed outside molds, driving the bus, etc..

https://www.youtube.com/watch?v=sy7ieraU-Ns

I have used, and taught, both methods. Each has it's advantages and drawbacks.

The work board method really facilitates getting the neck alignment right, always provided you made the work board correctly in the first place, of course. The measurement to watch there is the projection of the neck surface at the top where the bridge goes. If you get that right, and the neck is aligned on the center line of the guitar, you'll be OK with that. The disadvantages are that, with the traditional method, you can't remove the neck once it has pitched up too much to lower the saddle any more. One traditional way around that is to use a very thick fingerboard, which allows you to plane it down in the future to correct the action. Joining the top to the sides with tentellones takes some time. It's harder to get the outline really right, and the sides perpendicular. Carving the heel before you plug in the sides is a bit of a pain. It's harder to make the binding routs, since there will be stretches where you have to do it by hand. Finishing the neck to body joint it more difficult.

Building the neck and body separately makes a lot of the trim and finish stuff easier. However, it makes getting the neck alignment correct a bit of a chore. This is the biggest struggle for almost all of my students. You can profile the sides with radius sticks easily enough, although it's quicker and more accurate with a dish.

I'd say neither method has much of an advantage overall. A lot will depend on what sorts of tools, and tool chops, you have.

Alan you are talking about the traditional Spanish foot and neck joint? If you do a bolt on or even a dove tail you can build the whole box on the work board then set the neck. I think IIRC that is more or less how Cumpiano does it, but with his complicated pinned neck joint.

One of the issues with deciding which approach to use is that there is no good comprehensive reference for what we term 'modern steel string guitar' construction, which is to say: outside mold, radiused top and back using radius dishes, go-bar deck, and modern neck joints. Although Mr. Cumpiano has changed much of his building process as presented in his book, those using building boards still have some sort of unitary reference for the construction method, so there is far less mystery that with modern methods, where guidance is a little more fragmentary.

For what it might be worth, Mr. Cumpiano developed and uses a bolted neck joint as detailed on his web site - we don't know of anyone that uses the pinned joint as portrayed in the book, although from what I understand, one of Mr. Cumpiano's mentors continued to build with it for a time.

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Are you sure??!!

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Sure as to anything available at a reasonable price. There's also the small matter of having to view all illustrations in Australian texts whilst standing on one's head for correct orientation.

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For the times they are a changin'

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I started reading the Design book, decided I was not prepared, and went to the Build book - which has been worth every penny.


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So now you've edited your post to say its not comprehensive? Have you read it?

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

I cannot say that in editing my earlier, I was focused at all on 'it' - assuming the 'it' in your sentence is your delightful literary effort...more the general case as explained below.

Yes - I did borrow both volumes, as well as Mr. Somoygi's books, Kinkaid, Young, and pretty much anything which could be begged, borrowed, or to be had on inter-library loan. My impression remains that there are books intended for the first time builder and books intended for those that seek to move beyond mere craft instruction and their first few instruments, and to gain some technical understanding of the whys of the hows already presented.

For first time builders, none of the relatively recent beginner-focused books do nearly as complete a job as Cumpiano, and some provide what seems to me to be questionable guidance in key areas (e.g., Willis's Step-By-Step Guitarmaking's use of a Spanish heel) or presentation which seems more pretty than useful (Kinkead's Dorling Kindersly-esque Build Your Own Acoustic Guitar).

Beyond those books intended for first-time builders sit your efforts, Mr. Somogyi's Responsive Guitar volumes, Hurd's Left Brain Luthierie, and increasingly technical, less craft-oriented treatments of acoustics, mechanics, and topics guaranteed to transition even the most dedicated insomniac directly in REM sleep. To describe your books as being somewhat beyond Cumpiano is not some veiled condemnation, but rather acknowledgement that you have succeeded in what I assume was your goal of moving beyond the 'do this, not that' of craft instruction to informed technical competence.

That Cumpiano remains the standard reference for new builders despite being so long in the tooth suggests to me that the needs of a new builder are sufficiently unique to make a more modern version both necessary and welcome. I would like to see a treatment at a similar level, comprehensive in the way that Cumpiano is (technique and practice-heavy; theory and engineering-light), and priced within reason for a person thinking about dabbling in the craft versus investing in it.

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For the times they are a changin'

- Bob Dylan

You go for it Woodie! See how much it costs to get it on the shelves and how much you make from it. Then let me know if it was worth doing!

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

When IS the Maryland method manual coming out?

New username, same Pat Mac

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Pat

Trevor—

First, let me say that I am in awe of the work you and Gilet put into your books. For a person who has built a few guitars and wants to dig deeper, they are wonderful resources. Also, the build volume is a darn good guide to molds, dished workboards, go bar decks, and the like. Standing alone, the build volume really might work for a first time builder.

But . . .

They are a two volume set, and cannot be purchased separately, right? Given the high price (I’m not saying they are not worth the price; I’m saying that the are expensive books), and the undeniable fact that the design book is WAAAAAAY over the heads of all beginners (and many experienced builders, to be honest), I would not recommend it for a beginner. As out of date as parts of the Cumpiano/Natelson are, I still think it is the best single resource for someone to use in building their first guitar.

Now, if you really wanted to go after the beginner market, you could allow someone to buy just the build book and not the design book. I understand that there would be downsides to doing that; I’m just saying that I think that’s what it would take to make your build book a viable choice for a beginner.

Again, I say all of this out of love for your work and your willingness to share your knowledge with the world.

I was just looking for opinions on which method is generally used to build a “ steel string “ guitar. I already have a full time job that keeps me pretty busy and allows me to pursue things like “ learning to make my own guitar” for my own use, because I play guitar a lot and enjoy it. In the future (additional builds) I might improve my luthier skills well enough to produce a product that I can gift family members who also enjoy playing guitars, but I have no intention of building a guitar for the purpose of resale. Therefore methods that are based on highly productive repeatable processes or efficiency is not a main concern. Quality and usability of the end product is my main priority.

On that note: I cannot speak for everyone, but this endeavor is a somewhat “ costly hobby “. And I for one would not invest 255 dollars on a book that has tons information I will never use, and what I can use is freely accessible on the internet if you have the desire to pick through various builds and pc together processes used.

I agree that for a beginner such as myself a book on “ the basics of modern building techniques “ would be welcome, and I would be inclined to purchase it for a “ fair price “.

Well that's enough about me...tell me what YOU think of me!

But seriously...let's get back to something closer to the OP's question. Much as I'd like to believe that the Cumpiano replacement would be a traditional book, that would be unfortunate for both author and user, as beginners guides tend to be quickly relegated to the back shelving of the shop to gather dust until passed on to another beginner by the now jaded pro, and - looking at the calendar - it's not 1987. More advanced texts with broader purpose, such as Mr. Gore's or Mr. Somogyi's efforts, are far more likely to be referenced in day to day use than something like Cumpiano, so the limitations of print and static graphic content are far less of an issue in supporting the intended use. That does not suggest that a new builders guide does not need to present a complete method and selection of techniques, but does imply that purpose and use define media and content.

So the issue may be broadened a bit to include how best to deliver the relevant information needed in the 2020's to allow a new builder to move from first steps to completed, playable instrument. What is needed in my opinion is a mix of text, graphics, photographs, and video - each supporting the other and used where that medium's core strengths are leveraged and other media used to mitigate weaknesses. Mr. David Schramm's online classical guitar construction class is as close to an exemplar for this approach as I have seen, and extending that template to a full multimedia exposition at a level intended to support a first time builder appears like a worthwhile task for anyone wishing to supplant Cumpiano as guide and temporary sage for the new builder.

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For the times they are a changin'

- Bob Dylan

" Quality and usability of the end product is my main priority. "

"Guitar Making: Tradition and Technology" will get you there. If you are careful with your materials selection and have some common hand tools a first guitar need not be terribly expensive - tuners are the single most expensive component of many of the guitars I build.
Publishing material that is somewhat esoteric in nature might be more economically and remuneratively done as a PDF document (and also more easily updated and revised).