Truss rod

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Zen
Posts: 301
Joined: Sat May 26, 2012 12:35 pm
Location: Ireland

Re: Truss rod

Post by Zen »

B. Howard wrote:Have pondered this a bit more here, and just to confirm my previous thoughts the feeler gauge you are using when you get the .25 measurement is real thin and flimsy? or is it thicker like the tip of a small screwdriver?

You got it Brian --its the thin and flimsy one --definitely not 1/4 inch
RUSTY
Zen
Posts: 301
Joined: Sat May 26, 2012 12:35 pm
Location: Ireland

Re: Truss rod

Post by Zen »

B. Howard wrote:Have pondered this a bit more here, and just to confirm my previous thoughts the feeler gauge you are using when you get the .25 measurement is real thin and flimsy? or is it thicker like the tip of a small screwdriver?

Brian --just realized the feeler gauges are metric--so its 0.25 mm

Sorry for any confusion--I live in Ireland and have metric measurements as well as what I call OLD MONEY measurements--ft and inches. I am nearly 60 so never really got my head around metric anyway and it too late for that now !!

Thanks so much for your input by the way.

I did back off the truss rod last night but only makes the action higher--so thats my dilemma

With the trussrod full on and without a capo, theres a full 1/16th inch gap between top of fret and underside low e string at First fret
Theres just under an 1/8 inch gap at 6th fret
theres a little over an 1/8th at the 12th fret

The stew mac slotted straight edge shows a slight gap on the fretboard between the 5th to the 9th fret

Thanks again
Rusty
RUSTY
B. Howard
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Re: Truss rod

Post by B. Howard »

AHHH...it's a met-trick measurement. That explains a good bit, 0.25mm looks like a good starting point for relief to me so why don't you set it back to that and take a look at the nut. Put a capo across at the second fret. How much clearance is there between the first fret and the bottom of the string? The strings should just barely clear the first fret. If they touch the first fret your nut slots are too low. If there is more than a few thousandths of an inch there your slots are not deep enough.
You never know what you are capable of until you actually try....

Brian Howard
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Zen
Posts: 301
Joined: Sat May 26, 2012 12:35 pm
Location: Ireland

Re: Truss rod

Post by Zen »

B. Howard wrote:AHHH...it's a met-trick measurement. That explains a good bit, 0.25mm looks like a good starting point for relief to me so why don't you set it back to that and take a look at the nut. Put a capo across at the second fret. How much clearance is there between the first fret and the bottom of the string? The strings should just barely clear the first fret. If they touch the first fret your nut slots are too low. If there is more than a few thousandths of an inch there your slots are not deep enough.
Capo on 2nd Brian

Bass side has 0.10 mm on First fret
treble side has 0.05 mm on First fret

So seems ok to me ?
RUSTY
B. Howard
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Re: Truss rod

Post by B. Howard »

Rusty, that looks good for the nut slots. So now let's talk about the bridge and saddle. Based on the action heights you listed earlier in the thread of 5/32" at the 12th that tells me your saddle height needs to drop about 1/8" to get the action down to 3/32" which is something most would consider decent on the bass side. You want to have at least 0.075" of saddle above the bridge when you are done, preferably a little more like 0,100". If you will not have this much you may need to shave the bridge itself down as well, which may require making the saddle slot deeper too.
You never know what you are capable of until you actually try....

Brian Howard
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Brian howard's guitar building & repair blog
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Zen
Posts: 301
Joined: Sat May 26, 2012 12:35 pm
Location: Ireland

Re: Truss rod

Post by Zen »

B. Howard wrote:Rusty, that looks good for the nut slots. So now let's talk about the bridge and saddle. Based on the action heights you listed earlier in the thread of 5/32" at the 12th that tells me your saddle height needs to drop about 1/8" to get the action down to 3/32" which is something most would consider decent on the bass side. You want to have at least 0.075" of saddle above the bridge when you are done, preferably a little more like 0,100". If you will not have this much you may need to shave the bridge itself down as well, which may require making the saddle slot deeper too.

Thanks Brian---theres about 3/32 across the saddle as it stands.

So, not enough it seems as I had already shaved a little off originally when I did a quick set up after building the guitar.
Is there any point in putting in a new saddle and starting again?
Or, would I be able to sand that amount needed from the top of the bridge instead

I'm attaching a couple of poor quality pics from my phone
You do not have the required permissions to view the files attached to this post.
RUSTY
B. Howard
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Re: Truss rod

Post by B. Howard »

3/32" would be a good height for the saddle above the bridge. So it looks like you may need to lower the top of the bridge, but that depends on how thick the bridge is now. the thickness of the bridge should be between 5/16"-3/8" as an ideal. I definitely would not want to see a bridge thinner than 9/32". So if your bridge is currently 7/16" thick you can plane or sand it down. If it is not, then you are most likely looking at having to reset the neck to achieve the proper geometry.
You never know what you are capable of until you actually try....

Brian Howard
www.brianhowardguitars.com
Taylor authorized service
Custom finishing services

Brian howard's guitar building & repair blog
http://www.brianhowardguitars.com
Zen
Posts: 301
Joined: Sat May 26, 2012 12:35 pm
Location: Ireland

Re: Truss rod

Post by Zen »

B. Howard wrote:3/32" would be a good height for the saddle above the bridge. So it looks like you may need to lower the top of the bridge, but that depends on how thick the bridge is now. the thickness of the bridge should be between 5/16"-3/8" as an ideal. I definitely would not want to see a bridge thinner than 9/32". So if your bridge is currently 7/16" thick you can plane or sand it down. If it is not, then you are most likely looking at having to reset the neck to achieve the proper geometry.

Its exactly 7/16th Brian
I'm assuming the planing/sanding has to be done right across the top of the bridge including over the peg holes.

Thanks
Rusty
RUSTY
B. Howard
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Re: Truss rod

Post by B. Howard »

Zen wrote:
B. Howard wrote:3/32" would be a good height for the saddle above the bridge. So it looks like you may need to lower the top of the bridge, but that depends on how thick the bridge is now. the thickness of the bridge should be between 5/16"-3/8" as an ideal. I definitely would not want to see a bridge thinner than 9/32". So if your bridge is currently 7/16" thick you can plane or sand it down. If it is not, then you are most likely looking at having to reset the neck to achieve the proper geometry.

Its exactly 7/16th Brian
I'm assuming the planing/sanding has to be done right across the top of the bridge including over the peg holes.

Thanks
Rusty
Yes, you need to lower the entire top of the bridge. Try to maintain the same contours as you have now. I would recommend some poster board taped over the top around the bridge to protect it. I prefer a nice sharp block plane for this operation, but sanding will work as well.
You never know what you are capable of until you actually try....

Brian Howard
www.brianhowardguitars.com
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Custom finishing services

Brian howard's guitar building & repair blog
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B. Howard
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Joined: Wed Jan 11, 2012 9:42 pm
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Re: Truss rod

Post by B. Howard »

You may need to deepen the saddle slot after cutting down the bridge, if the slot is too shallow there will be trouble.
You never know what you are capable of until you actually try....

Brian Howard
www.brianhowardguitars.com
Taylor authorized service
Custom finishing services

Brian howard's guitar building & repair blog
http://www.brianhowardguitars.com
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