Hello guitarbuilding people!
I have made a couple of bolt on necks with single action truss rods (The usual ones with the upper part that push upwards when tightened).However i want to try and make a neck with a anchored truss rod (Square anchor) with adjustment at the heel...Like the old Fender slapboards.I have tried to work out slope and measurements for the rails needed for routing the slot for the truss rod,but i´m not entirely sure i get it right.Do some of you guys have experience doing this?.I guess my main questions are:
How far down should the sloped route go for the truss rod to function properly?
And where should the depth peak?.In the middle between nut and heel or a little further in the heel direction where the neck is thicker?.
Is there anything special i have to look out for when gluing in the fillet?.Do you add silicone in the bottom of the slot before gluing?
Thanks 🙂
https://www.youtube.com/live/pjcjeMmRxNE?si=s7z8uhbKSFpTRCrZ
Mark Bailey tutorial
I'd suggest making a side section drawing of the neck so you can see clearly what's going on...if you do that and then take a photo of your drawing we can check it out.
A couple of notes:
Make sure the slot will leave at least a good 1/8" 3-4mm of wood at the back of the neck.
You don't need silicon in the slot - the fillet will stop the truss rod vibrating (that is its main purpose in life).
You can also use heat shrink tubing to 'wrap' the truss rod (i've also use drinking straws...) but it's not really necessary.
Thanks @clinton for posting the video - hopefully that will answer the Q's but if not we're here to help!
Measure twice, cut once...
Thanks Clinton!.Yes i have watched that video several times.I would love to try to make a one piece neck one day but i think i would start with the less scary version with a fretboard on top of the slot first.Concave routing instead of the convex like Mark does in the video.
Thank you Mark!.
This is my initial (Crappy) drawing (I can´t seem to draw a decent curve freehand :-D).+ the 5mm diameter truss rod i intend to use.Truss rod-anchor has a height of 10mm..Which should get the slot down to a depth of 7.5mm at the anchor end.The truss rod nut is a 9,5mm vintage style nut.Ideally the hole for the nut should "Dip" 1mm into the bottom of the rosewood fretboard to get a steeper angle...Or at least i think that is why Fender did it??.
Forgot to mention that i will use a 21mm maple blank for the neck with a 4.7mm(Approx.) rosewood fretboard on top.
Is it better to have the max depth further towards the heel end (Rather than in the middle) to get the channel as deep as possible?.I worry about the slot being too shallow...Maybe i should´nt?.
I did a test run on some scrap wood with some prototype rails in MDF.Seemed to work fine...though i´m not too shure about using MDF for the final setup.
I tried to work out a radius curve for the slot but that is +3 meters (Don´t know how to draw that accurately)..Is it ok to do a freehand curve as long as it has´nt got lumps and bumps?.
Cheers 🙂