Welcome to CBN, it is slow right now not much activity. Most of the questions you have asked are subjective to how comfortable the cbg feels in your hand. For me 2.5 mm or 1/8th inch at the 12th fret and at the first fret just high enough to slide a business card between the fret and string. If I have a fretboard on top of the neck I use its thickness as a guide for how high above the sound board I place it. My back angle is about a 3/16 to a 1/4 inch lower at the bridge it just depends on where I place the bridge and the fret scale I used. The bottle cap piezo will work on vibrations of the sound board more than string movement.
Come to think of it My first cbg I made had a very high string it was close to 10mm and although it did not have a fret board I remember trying to fret it at the 2nd fret D string and darn near ripping my finger nail off. Bled for about 15 minutes. I think it was Lennys CBG 101 on youtube.
If I was you I would learn as much as you possibly can from your first build, use it to try out things and take your time.
The silent forum strikes again.
Measure & use the string height of your favorite electric or acoustic guitar (depending which strings you plan to use).
Actually don’t own any other guitars. I think I remember seeing somewhere (I’ve watched SO MANY videos and read SO MANY articles) that at the 1st fret it should be like 1-2 playing card height and like 10 cards at the 12th or something like that. Can’t seem to find the info again.
I wouldn`t worry too much about the string height as you can always make it high, then try it out and lower it to suit yourself. It`s easier if the nut is bone and can be filed down rather tan using a bolt but even that can be adjusted by lowering the slot where the bolt sits.
The bridge, likewise can easily be adjusted to suit yourself. The fact is you`ll be best to keep your first build as simple as possible and learn from it. Guaranteed that you will end up making more.... many more!
Probably the best tip is to fret it first then work on the nut and bridge.
Want to say THANK YOU to everyone that has given me advice/tips and links to follow to help with my first build. Am planning to hit it hard tomorrow and will definitely drop pics when I finish. Such an awesome community!!!!
Hi Jason, lots of good info already offered on action hieght. I was a bit confused regarding your 10mm reference, I think you were referring to the bridge height. If so, 15mm is an area I shoot for. it gives a good break angle for the string and puts the pressure "loading' down onto the top for better response.
I have a stack of old gift cards & hotel room key cards. They come in handy for measuring & for temporary shims. Most measure right at .030".
If you don’t have one of these, then get one, well worth the 4 bucks & free shipping from MGB. Card sized, but unlike playing cards, it has a way to accurately measure & has several modes of measure: inches- 32/64ths,millimeters, centimeters,Etc. I also use it as a straight edge for leveling frets? Cheers :)