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Do you dome your tops completely, or do you make your tops flat above the soundhole?
And if you dome your tops completely, how do you dial that dome in to string hight, bridge thickness and saddel hight?

Personally I've been using a 28' radius on all my braces except the Upper Transverse Brace which is 60' radius.
You can dome all the top to the same radius and dial that dome in to string height, bridge thickness and saddle height by flattening the top in the area between the neck block and the UTB, especially if you use a neck block extension under the fingerboard- it doesn't remove much material from the soundboard. I did that on my first 2mor 3 builds.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I domed my top in a radius dish to 25' but after all was said and done with the bracing I seriously doubt that I had a 25' dome. I also used a flat UTB upper transverse brace for flatish above the sound hole. Toward the end of my building I took a suggestion from Todd Stock I believe and went with a 55' UTB if I remember correctly, that was a good idea.

Now as for how I integrated neck angle to this domed (whatever it turned out to be after I lightened the bracing considerably) and the reverse dome on the bottom of my bridges I built the box and closed it and then simply fitted the neck and bridge to what is/was. This is also what repair luthiers (like me) do everyday somewhere when we reset a neck we fit the neck to what is dome wise including nothing at all at times and adjust the neck angle accordingly.

Some also factor in top rise under string tension and I never went that route and it did not seem to make any difference with my guitars and if it did that's what making saddles is for including taking into account seasonal changes in the dome if one lives in a place like I do with dramatic seasonal change. I do find it beneficial to have a winter and summer saddle a Mario P. idea but not factoring in top rise under string tension never resulted in saddles that were too tall or short with how I did it.

I've read for years here about others factoring in top rise and I have asked some of the professional builders that I know about it and it seems to be more prevalent on this forum than in the wild but I could be wrong. It does provide wiggle room on the underset side of neck angle and that may not be a bad thing but again I never found it necessary. This may be because I deflection tested my tops for stiffness and only built with very stiff tops. Mine may not have moved much if at all.

Even with my lightly built guitars string tension did not seem to change the geometry on my Heshtones enough to matter.

So for the details I braced tops to 25' in a radius dish and go-bar deck. When I glued on the UTB I pulled the radius dish from the go-bar deck and replaced it with a flat board.

The advantage of flattening the upper bout and there is a tutorial here on the OLF that I wrote 15 years or so ago called "Flattening the upper bout" is the fitment of the neck and fretboard extension. It seemed to result in some natural fall-away (desirable to me) and help the fret board fit tight where it wanted to curl inward toward the body because of fret compression and how close the frets are there.

So on a conventional, steel string flattop I wanted to see fretboard extension fall-away of 0.010" - 0.015". This to me makes fall-away an important consideration for a steel string not mentioned in your question but it should be addressed and can be addressed in whatever method we use.

Hope this helps my friend.

Thanks for the reminder Hesh, the post is here - https://www.luthiersforum.com/forum/viewtopic.php?f=10117&p=349173#p349173

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I use 28 but in reality once you glue the braces to the top your dome is not 28 and will vary by the RH conditions. Here is the important thing to consider.
NECK ANGLE
I incorporate this into the sides as i drive the bus
this video will help you understand the geometry involved.
prepping the rim
https://www.youtube.com/watch?v=LrgRKKsxL-M

setting the neck

https://www.youtube.com/watch?v=FNcbA1P95KE

What you want to know is that the fretboard should come on the top straight with a slight fall off. The
string height at the bridge and saddle when all said and done should be about 1/2 in off the top. So pay attention to this geometry
as you build. A 1 1/2 degree neck angle should be about where you end up. After 25 years of this I find the top will usually rise under a 1/16 of an inch. So allow a few days for the guitar to settle in before making final adjustments.
My goal is 1/16 in to 3/32 at the top , where the saddle will be when I plan my neck set. Once you glue the top on , if you place a straight edge on the upper part of the top you should see this gap at the point of the saddle. Take your time in the prep of these details and you will be perfect.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

Thank you to Hesh, my friend, and Colin for the link to Heshs tutorial from 2010! And thanks to John for the links to the videos. I am very greatfull for your tips, tricks, advices and sharing your excellent knowledge and expertise of luthiery with us! Every day I learn something new that helps me to solve upcomming problems now and in the future and to avoid mistakes. You keep me thinking about every step in my guitar building BEFORE I make it wrong because of not thinking deep enough about it!

I use a 25' dome on all the bracing. As Hesh says, you just have to fit the fingerboard end to the top. Rather than try to work on the hard ebony (or whatever) I like to set the end of the neck a little higher than the top, so that the fingerboard contacts the top just at the upper edge of the sound hole when the neck angle is correct. This 'over stand' usually amounts to about 2mm, more or less. I glue a wedge of the same wood as the neck under the fingerboard stub, and dress that off. This also avoids making the end of the fingerboard too thin.