Reducing Neck Relief with a Non-adjustable Truss Rod
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- Опубліковано 24 січ 2023
- Reducing relief with a non-adjustable truss rod without using compression fretting (because I'm use Evo fretwire).
1) shape the fingerboard
2) dress the frets under tension
3) stiffen the truss rod
[Fixed a blank spot in previous version of this video]
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Bryan, this is a wonderfully instructive video for me as I have a D-18 Authentic 1939 Aged. So far it has needed nothing and the neck relief on it is perfect for me. Thanks for taking the time to make this video!
All of the A's with the T bar I have seen have been really good. I had to do a compression fret job on the one with the ebony truss rod and there's a video on that.
Bryan,
I am former customer and still loving the Martin you improved for me.
Am an amateur luthier so have some experience and completely get your multipronged attack on this. I have exactly this problem on a 1970's Martin D-18 12 string and the issue is a spongy neck. Compression fretting and and a neck reset might get it fixed but I like your conservative approach trying to exploit every opportunity to stiffen the structure of the neck. Just brilliant.
Great video and easy to assimilate. I just wondered if a series of rings, or a spiral could be lightly ground onto the carbon fiber rod to take epoxy with it inside the hollow square tube? 1/4” is pretty small, but the groove(s) don’t have to be deep. Also a chamfer on the tip that goes in first. Maybe its not worth all that trouble anyways.
The carbon fiber rod is square... it won't turn inside the truss rod. The dowel is wood and round and turns. I feel that I'm getting enough glue in there, esp with the expanding Gorilla Glue. I just don't see any advantage to using carbon fiber because you would have to have a PERFECT fit to add any kind of significant strength to the rod. I suppose someday I could measure deflection on the rod I have, then fill it with CF/epoxy and see if the deflection changes. But, I really think that most of the fixed truss rod issues are caused by the rod slipping in the neck channel and not deflection of the truss itself.
Great video, thanks for posting. Very clear explanation, albeit well beyond my skill level. Looking forward to the follow-on videos. Thanks again.
If you never do it yourself, at least you can understand how it's done.
Excellent
Great video, Bryan! How much weight is in the two sandbags that you use to simulate string up tension?
Sorry... I meant to state that. The two are right about 7 lbs. Of course, you need to decide where YOU are going to set them on the top and if you want to be really picky, some necks react a little differently so you might want a little less or more weight. But I've found those bags, there, on a 70's, to be good enough.
if the fretboard is made of really hard material and there is enough difference between the slot and tang sizes..then you will get some backbow..
That's a compression fret job of which I have done dozens. Here's one: ua-cam.com/video/H34S3NrcT00/v-deo.html
However, as I stated in the video I am NOT doing a compression refret on this because we wanted to use Evo wire and Evo only comes in 1 tang thickness. Plus, this is a D-18 which does NOT have "really hard material" for a fretboard. So, neither of your qualifications were met, thus the need to plane backbow into the neck.
Too bad they didn't make thicker tangs on fret wire, you could use a few to help thicken one to put the neck into a back bow too, like they used to with bar frets.
They do with nickel silver frets but I'm using Evo here.
If it’s more deeply bowed do you ever heat and clamp the neck to try and bring it back into normal range? Seems like this is a bit controversial and wondering your thoughts
In 25 years, I've run across maybe 3-4 guitars that were so bad that shaping and/or compression fretting wouldn't take care of them. On a 70's with the square tube, sometimes the rod is unglued. A decent way to bolster that is to drill a small hole under a fret at both ends of the neck, back-bow the neck a little with sandbags, and inject West Systems thin epoxy. On another 70's, I just pulled the fingerboard and put an adjustable truss rod in. mid 40's with ebony rods can be a problem but I'd rather reshape the board/frets with the current stress-shape, than try to re-stress the thing.
To answer your question, heat pressing rarely holds for very long... it's better, IMHO, to FIX the problem.
@@Bryankimsey makes sense, thx!
is that an old Taylor back there you're working on?
Nope. I haven't had a Taylor in a long, long time.
Ahhhh.... good eye. That's a Taylor case! Customer shipped his Martin in it though.