12 string slot head

[liam_fnq]

hi all, I'm about to start my 2nd build and would appreciate some advice on a 12 string slotted headstocks. something is making me think that if i don't get the dimensions and headstock angle correct, that i could have strings bumping into the edges of the slots. is that correct? or am i overthinking things? I dont have one to measure off.
any advice would be greatly appreciated, while actual dimensions/ angles will gain you a smilie face badge

thanks in advance..........liam.

[Arnt]

Sorry, I don't have those numbers for you. The dimensions and angle of the slots etc depends on many things, like nut width, distance between nut and string post, headstock thickness... Unless you are following a good plan or copying an existing instrument, it is a good idea to draft everything with great detail. The geometry is kind of complex and the clearence between strings / slots / posts can be pretty small and hard to draft accurately, so some even choose to make headstock mock-ups to make sure everything works when designing new headstocks. It doesn't have to be fancy.

[seeaxe]

Liam

I've been meaning to do this for a while, hopefully not too late

photos of my (somewhat unloved) 12 string Yamaha slot head

Front

Side

Back


Looks to me like the neck angle is the standard 15 degrees, overall length of peghead from nut to tip is 209 mm and its mm 67 wide tapering to 60 mm wide and 20 mm thick.

If you let me know what other dimensions you want, I will measure it for you and post a reply.


Cheers

Richard

[kiwigeo]

Arnt is on the money.....do up a drawing of the headstock with nut and check on string path from nut to tuner shafts.

[jeffhigh]

With a Slot head the headstock angle is reduced from 14 Deg to closer to 10 degrees because the strings anchor below the face rather than above the face

[liam_fnq]

thanks guys, all info is much appreciated.

i think i'll do up a detailed drawing to check it all fits. of course, with a slot head its a little more complicated than a paddle head as two views must be drawn and cross referenced to check that the string dont hit the slot.

luckily i developed mad graphics skills at high school

unluckily i didn't develop mad CAD skills

Richard, there is one measurement you could make for me. nut width and string spacing. thanks.

and thanks again. Liam.

[Lillian]

Liam, if I can help with the CAD let me know. It's what I do all day, except on the Civil side of the house.

[seeaxe]

Liam, mate, sorry for the delay. Measurements are of my Yammy FG512, made with digital calipers, (which may not have been invented for people like me whose eyes are packing up, but they sure make measuring things a truckload easier!)

Nut width = 48.5mm

Space between strings varies between 2.87mm on the treble side to 2.0mm on the bass, because of the larger string gauge. Strings are med to light.

Distance from out side to outside of strings at the nut = 42.6mm

Distance from out side to outside of strings at the bridge = 59.5mm

You're going to need some serious bracing - theres a lot of force in 12 strings. One advantage of the smaller guitar is that the braces arent spanning as far.

The NGR looks sweet - I have got some of that too, I think. I am going to have a go at a neck with it and possible some sides for the travel guitar.

Your build looks really neat - cant wait to see how that turns out.

Cheers
Richard