Discussion in 'Luthier's Guitar & Bass Technical Discussion' started by Kmaz, Dec 5, 2017.
Is a straight edge the most accurate option for measuring a guitar's neck relief?
Just capo the first fret, and press the string against the last. Measure in the middle. You can use feeler gauges or a string gauge.
Yep. What ^^^^ he said. A string makes a dead-sure straightedge.
Check online for the setup specs for your guitar. Typically you'd fret the first fret and the 17th fret, and check relief at the 7th fret. Depending on the guitar make, somewhere between .006" - .010" is typical.
I do what first poster suggested
I use .010 feeler gauge
as long as it slips under without moving the string and there isn't a huge gap between it and the string, ive got a straight neck with just a tad relief
I also tap the string down...it should make an audible click sound but not move much
+1 boyce89976. Fret where the neck meets the body, not the last fret.
I don't know whether this needs to be stated in this thread, but .... I sorta feel like I should, so here goes.
The issue with adjusting relief is that the relief changes as the weather changes. The degree to which is changes varies with individual guitars, but as humidity goes up, relief goes down. I live near the ocean in CA, so the humidity usually between 50%-75%, but it regularly drops to 25% too. The changes in humidity changes the relief in some of my guitars by .008, but most in the .004 range.
That means I gotta adjust the relief in some guitars a couple times a week, if the weather is wacky and changing a lot. Some of my old guitars are very settled and don't move much, and some aren't that settled and they move more. They all move a at least little in response to changes in humidity.
In my 'world', I adjust the relief a lot. Sometimes I have it set for a Wed gig, and I have to re-adjust it on Sat 'cuz the weather has changed.
That's my only point to this post - relief changes with the weather, and if you're picky about your action, like I am, you may need to adjust the relief on some guitars often. The exact measure of relief is therefore a bit of a moving target, 'cuz these dang guitars are (mostly) made of wood, and they change with the weather.
There's an old pithy saying that Women marry Men thinking they'll change them, and are surprised when they discover they can't. Also, Men marry Women thinking they won't change, and are surprised when they do - Ha ha. In this pithy example, guitars are more analogous to women - they change. The one 'constant' is that you always need to check your relief - it may change.
Thanks, Dana O.
Wow, Dana once or twice a week? I don't think I have tweaked the rod on one of my guitars after the initial set up in I don't even know. I sometimes look as I am changing strings, but unless there is a noticeable difference in playability, I don't even think about it.
Do you use a really low action?
Sounds like a case of O.C.D. to me...but seriously, if it works for you, cool.
I thought it was the other way... as humidity goes down the neck straightens (less relief), and as humidity goes up the neck bends (more relief)?
I said it right - as humidity goes up, relief goes down (diminishes, becomes less). As the neck takes on moisture it swells, which pushes it toward a backbow and less relief.
Only if the weather is freaking. As I wrote, I live near the ocean in Santa Barbara, CA. Usually the humidity is around 70-80%, but if the wind blows in the right direction, it dries out quickly, nad humidity drops to 25%. Many times I've had to reset the relief on a couple Teles and Strats I have. I ALSO have an old dot neck 335 - that hardly ever moves, I've gone years without touching it. Every guitar is different. Also, If I'm traveling - sometimes it's 500 miles between gigs and the weather can be way different.
I generally like the action no higher than 4/32" measured at the 17th fret - I little higher for the low A end E. I used to be able to have it a lot higher, but I've had some issues with my hands the last 8-10 years and I'm way more comfortable with very little relief and action at 4/32. I usually have the relief around .005-.007, so if it gets humid, it can flatten out enough to where it buzzes, and I don't dig that.
Robben Ford's tech Daved used to adjust RF's truss rods before every gig - I'm not alone in this - LOL! 30 years ago I didn't care, but now I do.
The "BIG POINT" of my post was that relief changes all the time. What's important is to be aware of the connection between the humidity and the instrument. Guys like me may be moved to adjust the relief with weather changes, others may not be moved to adjust, but one thing is certain - the GUITARS are moving as the humidity changes, so it's good to be aware of that when you're setting your relief.
Thanks, Dana O.
Thanks, Dana for clarifying!
You have your action at 4/32"? Man, I could never play with it that high. I can barely play with mine at 4/64" at the last fret!
lol, I was gonna say...
I usually set minimal relief and action at the 12th around .070 (up or down a smidge depending on the guitar)
I’m pretty sure he meant 4/64”, which is basically Fender’s spec isn’t it?
You also have to do more maintenance, when you shoot for minimum relief or basically straight. If a neck has 10/1000, relief, the humidity moves, it has room to straighten before it buzzes. If the neck is already straight, then it backbows and it’s buzz city.
Like one of my basement doors. It is closing nice now but its a little too tight in the summer.
I adjust my relief as needed. Sometimes twice a week in the summer here in NY. When you like it in the pocket and your action is on the low side it’s needed. OCD? Maybe a little. You don’t tune up a Toyota as much as a Ferrari!
I live in southeast mi
I am tweaking relief now as it gets colder and dryer
I will readjust again in spring when it gets warmer and humid
twice a year..slight 1/8th turn adjustments on some
on others never adjust unless I am lowering or raising action
Yes, a proper straightedge is more accurate.
I use a Stew Mac precision ground straightedge and also use the fretted string/capo technique, and for strict measurement purposes...
A straightedge is more accurate because with a straightedge resting on the top of the frets, the feeler gauge either slides between the top of the fret and the straightedge or it doesn't.
When using a string, there's always an issue with the string deflecting to some degree or another depending upon the angle you hold the feeler gauge in relation to the fret top. When I measure using the string/capo and then immediately use the straightedge, the two always read close, but slightly different mostly due to the string deflection I described above.
OOOPS - that should be 4/64", not 4/32. Happy fingers typing quickly.
Thanks, Dana O.