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Fret tang width Vs Fret slot width
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Author:  Ed Haney [ Fri Nov 15, 2013 8:57 pm ]
Post subject:  Fret tang width Vs Fret slot width
I have Dan Erlewine's book on fret work from StewMc. He clearly recommends that the fret tang excluding barbs should be exactly the same width as the fret slot width. So a .023" slot would get a fret tang width of .023" for normal necks (i.e. non-problem necks such as new necks, that you are not trying to correct for back bow or forward bow). After speaking with StewMc, who does not publish their tang with anywhere, they verbally told me that all their fret wire has a .023" tang width excluding barbs (Matt went and measured it, he said.). The table saw blade that StewMc sells for slotting is published as a blade for cutting .023" slots. (Frankly, I was more than surprised that their fret saw blade, fret wire, and step-by-step fretting book all matched up!)

As a comparrison, LMI does publish their tang width and it is .020" excluding barbs. They also say that the .020" tang is correct for a .023" fret slot and they sell a .023" table saw blade for slotting. So over 14 frets LMI recommends 14x.003"=.042" more slop than the zero amount that StewMc and Dan Erlewine reommends. To me, that is a big difference.

For a non-problem new neck (nothing to correct), what fret tang width excluding barbs do you use with what fret slot width? Why (i.e. what is your rational)?
Author:  Nick Royle [ Fri Nov 15, 2013 9:02 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
Excellent question, can't wait to see the responses!
Author:  meddlingfool [ Fri Nov 15, 2013 9:12 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
I know that I wish I could find an .025 fret slotting blade. I prefer the slots to be a bit wider than the frets, so much so that I usually burn the slots a little wider with a hot knife.
Author:  Imbler [ Fri Nov 15, 2013 9:19 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
Ed, you made a mistake compounding the error over 14 frets. Assuming each fret slot is in the correct position, any individual fret could be off by only the .003. If you were cutting the slots based off of the position of the previous fret, your assumption would be possible, but the slots are cut independently, so the error cannot compound,
Mike
Author:  saltytri [ Fri Nov 15, 2013 9:52 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
meddlingfool wrote:
I know that I wish I could find an .025 fret slotting blade. I prefer the slots to be a bit wider than the frets, so much so that I usually burn the slots a little wider with a hot knife.


I use 5" .023 and .025 blades from this outfit:

http://www.malcosaw.com/ecom/category/11/
Author:  Ed Haney [ Fri Nov 15, 2013 10:57 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
Imbler wrote:
Ed, you made a mistake compounding the error over 14 frets. Assuming each fret slot is in the correct position, any individual fret could be off by only the .003. If you were cutting the slots based off of the position of the previous fret, your assumption would be possible, but the slots are cut independently, so the error cannot compound,
Mike


Thanks, Mike. I was/am not concerned with the fret slot location. All the slots would be centered on their correct location and would not be a problem.

My concern is that forward bow would be allowed if there is too much slot space which will compound. The truss rod could be used to combat some or all of this, but I think it best not to design in a potential problem and hope to fix it with the truss rod. But if LMI is "correct", there would be no problem and perhaps Dan's approach would produce a forward bow (but I doubt it since he usually gives good advice).

It seems to me that LMI and StewMc are significantly different. If both approaches work equally well, then the range of "correct" sizing is larger than I expected. I would think that the LMI extra space might requre hide glue or the like to fill the void, but LMI does not mention the need of such. No space, as Dan recommends, would seem to risk a back bow due to the barbs.

I hope to see some specific experiences of others with thier reasoning.
Author:  Ed Haney [ Fri Nov 15, 2013 11:05 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
meddlingfool wrote:
I know that I wish I could find an .025 fret slotting blade. I prefer the slots to be a bit wider than the frets, so much so that I usually burn the slots a little wider with a hot knife.


LMI has .025" blade (as well as the .023" blade) here http://www.lmii.com/products/mostly-not ... ing-system
Author:  meddlingfool [ Sat Nov 16, 2013 12:27 am ]
Post subject:  Re: Fret tang width Vs Fret slot width
Well, that's going to make my life a lot easier. Thanks.
Author:  Imbler [ Sat Nov 16, 2013 12:45 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
Ah, I see what you were saying now Ed, I misinterpreted your post. Thanks for the explanation!
Mike
Author:  Tom West [ Sat Nov 16, 2013 1:28 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
Ed: If I follow you correctly, your thinking that the stiffness of the neck is mainly determined by the fit of the tangs into the fret slots. While back bow can be introduced by tight frets I don't think it is a necessity, also frets that are a bit looser and do not cause back bow are generally OK. Lots of folks glue frets in both for lubrication and fit with holding power. That along with the stiffness of the neck with a good truss rule the day as long as the slots and frets are reasonably sized. The sizes you give fall in that range for me.
Tom
Author:  Ed Haney [ Sat Nov 16, 2013 1:44 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
Tom West wrote:
Ed: If I follow you correctly, your thinking that the stiffness of the neck is mainly determined by the fit of the tangs into the fret slots. While back bow can be introduced by tight frets I don't think it is a necessity, also frets that are a bit looser and do not cause back bow are generally OK. Lots of folks glue frets in both for lubrication and fit with holding power. That along with the stiffness of the neck with a good truss rule the day as long as the slots and frets are reasonably sized. The sizes you give fall in that range for me.
Tom


Thanks for your answer, Tom.

I do not think that "the stiffness of the neck is mainly determined by the fit of the tangs into the fret slots". I just think that it is a factor. Dan E. thinks that it is an important factor. He suggests that if I remove the frets and restring the guitar that I will see a large forward bow that the truss rod would never be able to remove. He suggests this test just to show that the fret slot does impact the stiffness of the neck and therefore the width of the fret slots Vs the tang width is an important consideration. So what is best? Dan thinks that .003" of extra space per slot (the difference between the tang and the slot) is too much for a proper fret job without glue. With .003" of space Dan would recommend adding glue to fill the void (and hold the fret in). My reason for starting this tread is to find out what others experience are. If one is always using glue then the extra space would seem to become a non-issue.

What should the fit be without glue? Is .000" to .003" a good reasonable range? Or is .000" to tight? Or .003" too much? Just asking for experience and wanting to learn.
Author:  Tom West [ Sat Nov 16, 2013 1:51 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
Ed: Very good, I get where you are coming from. Dan has his own preferences. I have just never seen this as a major problem, maybe because I glue my frets and use a good solid truss rod.
Tom
Author:  Burton LeGeyt [ Sat Nov 16, 2013 2:26 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
I've been thinking about this lately-
I'm at work now but can add more to this later this weekend. I just had some fret saws ground to thousandth steps (.02, .021, .022, .023) so I could control it more closely. I had to make a new arbor to use the 1" hole saws on my table saw.

Attachment:
JD-arbor-and-fret-saws.jpg


Think about bar frets and compression fretting, it HAS to make a difference how tightly they fit. I do not trust glue to stop the wood from compressing a bit around a loose fitted fret. Not that it doesn't still work as many many guitars show. However, if you are building for lasting effect I think you have to take it into account-
Author:  Tom West [ Sat Nov 16, 2013 2:42 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
Burton: Your absolutely correct if you are using compression fretting. Most likely with no truss rod. Otherwise with the given parameters I don't think it matters a hill of beans. If the guitar holds a given amount of relief,as set by the truss and any excess space is taken up with glue, things will work as they should. I see compression fretting and regular fretting as apples and oranges.
Tom
Author:  Burton LeGeyt [ Sat Nov 16, 2013 2:59 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
Tom, fair enough-

I think it depends on if you see the truss rod as something that is a structural part of the guitar or as insurance.
Author:  Tom West [ Sat Nov 16, 2013 5:04 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
Burton: Just for info. I use the Martin copy made from aluminum u channel and epoxy it in place. I think it stiffen the neck quite nicely........................I sense all the engineers hitting the calculators and coming back with "impossible". :D It works for me. Take care.
Tom
Author:  Mike Collins [ Sun Nov 17, 2013 4:10 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
I do not know if Shane at HMTW has any blades
left but his are .0245
Just perfect!
For .023 wire.

Mike
Author:  Chris.Conery [ Mon Nov 18, 2013 3:37 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
My secret to effective fretting is to use the Stewmac table saw blade (0.023 kerf), LMI fret wire (0.023), and the LMI fretting backsaw (0.023). When I run the backsaw through the slots made on the table saw, even though they all claim to be the same size, the slots become just enough wider to make installation easy and secure.

Cheers,
Chris
Author:  Ed Haney [ Tue Nov 19, 2013 7:17 am ]
Post subject:  Re: Fret tang width Vs Fret slot width
Chris.Conery wrote:
My secret to effective fretting is to use the Stewmac table saw blade (0.023 kerf), LMI fret wire (0.023), and the LMI fretting backsaw (0.023). When I run the backsaw through the slots made on the table saw, even though they all claim to be the same size, the slots become just enough wider to make installation easy and secure.

Cheers,
Chris


Chris,

I take it that you agree with Dan E since you are using the same size tang and fret slot (both .023"). Unstrung, do you have any back bow or is your new neck straight or what?

I assume you have used feeler gages to determine your slot size (no rocking of the feeler gage in the slot)?

On the current LMI site I count 11 wires with .020" tang, 1 wire (Evo, gold mandolin/dulcimer wire) with .023" tang, 1 wire with .019" tang, and 2 wires with .024" tang. Are you using the mandolin wire? Or do you have some old stock of a previous wire?

Thanks for your input.
Author:  Chris.Conery [ Tue Nov 19, 2013 11:44 pm ]
Post subject:  Re: Fret tang width Vs Fret slot width
Ed-

I stand corrected - the fret wire I use does indeed have a tang width of 0.020. So with the saw blade of 0.023 and some extra widening by the back saw I'm probably working with a slot of 0.024 or 0.025. So the extra 4 or 5 thousandths makes it easy to install the frets, they certainly don't come out, and there is no back bow - everything stays pretty darn flat. I'll take a feeler gauge to it tomorrow.
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