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fretting question

Posted: Fri Sep 25, 2015 11:11 am
by Greg Martin
Ive had a consistent problem in my process that needs to be addressed before the next build, what happens is my fret wire compresses the finger board in to a slight back bow and when all is said and done I end up with very little truss rod adjustment for relief. Ive always wanted to start from dead flat on the FB.
I use lmI 2 way truss rods and 2 graphite stiffeners. slots are cut before radiusing, then re cut to follow radius to final depth. my fb is then glued to the neck on a dead flat piece of granite,the board is re radiused with a 12" block then frets are arbor pressed in I mostly use cocobolo or ziricote for finger boards.
Ive always used Stewmac fret wire along with their .023 fret saws. Should the saw be .024 ? should I open the slots around the 6-9th frets and glue in ? or maybe compress the tangs some? I dont know !!! I figured you guys would know.

Re: fretting question

Posted: Fri Sep 25, 2015 12:18 pm
by Rodger Knox
I install frets before gluing the FB to the neck. This almost always induces a pretty severe backbow to the FB.
I clamp the FB with 1/4" thick blocks at each end overnight, and the backbow disappears.
It's a little different process with a different set of problems, but it does eliminate the problem of backbow from installing frets.
The other alternative is to overcut the slots and glue in the frets.

Re: fretting question

Posted: Fri Sep 25, 2015 3:50 pm
by Matt Cushman
When the fret barbs are too wide for the slot I just file off some of the barb till I have the fit I am looking for. I made a device for filing fret barbs down to size.

Re: fretting question

Posted: Fri Sep 25, 2015 4:14 pm
by Barry Daniels
I run a dremel with a tapered bit though the fret slots before fretting to make things go easier and prevent any back bow. The bit at the widest point is 0.027" in diameter.

Re: fretting question

Posted: Sat Sep 26, 2015 10:01 am
by Matt Cushman
I always try to preserve the slots as they are. That is why I alter the fret to fit the slot. Too much fret wedging is always a concern. Frets that are crushed into the slot are more likely to damage the board when pulled for replacement. For a good fit much of the wire is to wide for my slots LMII sized at .023" so I find it easier to size the wire rather than the slots. Filing off the barbs is a pain if you don't have a way to do it. Stew Mac. sells the fret barber but I like the price on my homemade unit, free. I made mine in about a half hour. Just drill a hole in some scrap wood put a pivot pin in to it. Then cut a groove to match your FB radius to accept the fret wire. This is the only tricky bit. To match the fret wire shape I used dremmel as a compass to cut the round part then I used a hobby knife to cut the square shoulder. Once the wire fits tightly in the groove filing them is easy. Just pivot a small flat file over a length of fret wire an voila! Along with guitars I build mandolins and with up to 29 frets in a 11.5" fingerboard span narrow fret slots are an advantage and wedging is considerable.

Re: fretting question

Posted: Sat Sep 26, 2015 6:07 pm
by David King
I used to file the barbs down with a 3 corner needle file but life is too short for that sometimes. I look for fretwire with a .020 or .021 tang width and .032 barb width and call it good. Once my frets are in I raise the neck up on blocks at each end and put my full weight in the middle to embed the tangs into the slots. That takes care of 90% of the back bow. It won't work after you've glued the frets in so do it as soon as the frets are in. To prevent tear out upon defretting you must file a bevel at the top of the slots with a 3 corner file. I keep a checklist for fretting which starts with washing the fretwire down with acetone so that the glue will stick later.

Re: fretting question

Posted: Sun Sep 27, 2015 12:06 am
by Dave Weir
If it is a consistent problem I would try the .024 Japanese flush saw from Harbor Freight. I use these with the Stew Mac 148 fret wires and don't have much trouble. I don't glue the frets and they seem to hold fine. I only use one piece neck/fret boards and some move a little, but no more than the strings can pull back.
Pretty cheap $6.00 experiment.
I take the handle off and tape long 1/8"x1/2" steel bars to each side. These act as the depth stop, and the handle, and also the extra length allows me to use all the teeth without it coming out of my miter box.

Also, if you don't already do it, pinning the fret board to the neck might help.

Re: fretting question

Posted: Sun Sep 27, 2015 2:10 am
by Michael Lewis
Try putting gentle tension on the truss rod, leveling the board, installing the frets, and then a final light fret leveling. This should give you a small bit of adjustment to release for controlling the relief. It's a simple concept and has worked pretty well for me for more than 30 years. Occasionally you may encounter a difficult neck that may require another approach, but this should take care of most situations.

Re: fretting question

Posted: Sun Sep 27, 2015 6:41 pm
by Greg Martin
michael is the gentle tension in a back bow of forward bow? how many thousands is good ? I just saw this from Dan E but to tell you the truth Im not liking building in a back bow even with a 2 way rod . ??? also would different fb woods want more or less gentle tension before glue up than others? Another point of concern is-- the rod slot,--using an LMI 2 way rod do you install a piece of wood over the flat of the truss rod or is the flat of the rod touching the fingerboard.What is the depth of the slot? and is your slot curved like fenders or flat like Gibsons or ? thanks
http://www.stewmac.com/How-To/Trade_Sec ... _neck.html

Re: fretting question

Posted: Sun Sep 27, 2015 6:46 pm
by Greg Martin
Matt do you file the tangs only in the 6-10th fret areas or every fret??
Dave a HF just moved in to my part of town,about 1 mile away,I think I will adopt the .024 saw and use it to open up the slots after radiusing the fb thanks

Re: fretting question

Posted: Sun Sep 27, 2015 7:06 pm
by Greg Martin
I thought I might try LMI for fret wire insted of stew mac I found this one which is nice like a jumbo.but whats the deal with evo/gold wire? for archtop pro con??
FW55090 0.113 0.055 0.090 0.020 0.033 so its .090 tall .020 tang and barb .033

Re: fretting question

Posted: Mon Sep 28, 2015 3:32 am
by Michael Lewis
The concept is to apply gentle tension on the rod (pulling back bow), then do the leveling. This establishes a flat fingerboard surface with a gentle tension on the rod, so it can be released to gain relief. If your neck is very stiff you may need more tension to move it. You shouldn't need much tension to make the rod work, if you do need a lot of tension it is not installed properly or the neck is excessively stiff.

EVO fret wire is pretty hard and will last a long time compared to nickel alloy frets. If you are just learning this stuff I suggest you use nickel frets for a while until you are comfortable doing all the tricks and processes to produce really good fret jobs, THEN move over to the EVO wire. The EVO wire is significantly more difficult to work than the nickel wire. I know some guys say there is little or no difference but you just try to level and crown a set of EVO frets and you tell me it isn't more work. Ahh, go ahead and get some EVO frets, you know you wanna try em. You'll see what I mean.

My point is that when you can do a really good fret job you get the frets in very evenly and need to take only the very minimum off their tops to get everything 'perfect'. This is the situation you should aim for, and requires the least work to have nicely crowned frets all on the same plane. If you have to take a lot of material from some frets to get them all to level you have a lot of work ahead of you to crown them and polish them up. This will seem like 3 times the work on EVO material.

Re: fretting question

Posted: Mon Sep 28, 2015 12:46 pm
by Greg Martin
thanks for your willingness to share what you know works. I will do as you suggest in prepping the fingerboard on my next build, in makes sense now. See ? you can teach an old dog new tricks .
Not interested in evo frets, just didn't know what it was all about.
do you glue in a cap over your 2 way truss rod ? if so how much do you compress the rod down as you glue in that cap.Im thinking of weather the slot nwould have to be a certain amount deeper?? So far Ive never glued a cap on a 2 way rod.

Re: fretting question

Posted: Mon Sep 28, 2015 3:28 pm
by Stephen Neal Saqui
Matt, above, mentioned this but it's worth a serious look:

A very simple tool to make is also sold by Stewmac called a "Fret Barber" (see link below). You can add additional shims for finer adjustment. I made mine from a block of maple, and a used mill bastard file which I put in a vice and broke off two pieces with a good whack from a hammer. Then ground down the two pieces to fit. Check the video.

The beauty of this is you can use all different sizes of frets without worrying about the tang being to big. And you don't have to over cut fret slots. The dremel idea is bad because once you've widened the slot you can't go back! The idea of fretting before gluing the fingerboard on is ok, but why not just make sure the frets fit the slots properly in the first place? Way better to modify the frets to fit right!

http://www.stewmac.com/Luthier_Tools/To ... arber.html

Re: fretting question

Posted: Mon Sep 28, 2015 9:19 pm
by Barry Daniels
You can suggest your own preferred techniques without calling mine "bad".

Re: fretting question

Posted: Tue Sep 29, 2015 12:56 am
by Greg Martin
I did the teeter glue in method only once,it had the slots dremeled to .028 i think then frets were epoxied in place.
this ws done on the fanned fret guitar i made in 1999. the neck was dead flat truss rod was nuetral radiused slots widened then frets 3-4 at a time were glued in.the method worked and has never failed ,no noticable tone diff either.but I dont know what the added value would be over say Michael's method ,plus it was messy and took more work and more time, but I had to try it once.

Re: fretting question

Posted: Tue Sep 29, 2015 3:00 am
by Michael Lewis
For rod installation, if all else fails follow the directions supplied by the manufacturer. I like the Martin style single action rod in the aluminum C channel as it doesn't place much compression stress on the neck. The stress is mostly contained in the C channel which imparts a bending force to the neck.

Re: fretting question

Posted: Tue Sep 29, 2015 10:42 am
by Greg Martin
wow didn't know anyone still used that style of truss rod, everyone seems all hung up on the 2 way rods. you are right about the force of the 2way rod on the neck .and finger board. After some more reading I see a split ,some makers install a cap some do not .Interesting.

Re: fretting question

Posted: Tue Sep 29, 2015 10:53 am
by Greg Martin
Michael is this the one you use? please comment on their info here!!!

TrussRodMartinSyleTRMR1221 LMI TRUSS ROD, MARTIN™ STYLE


Our two-way adjustable rod, is the same type of rod that Martin™ Guitar is using. The rod, made for us by Gotoh™, consists of a U-channel .360" deep by .400" wide and 15.15" long. Overall length of the rod, including the nut is 15.94", the nut is .79". A rod .200" is flattened at one end and welded at the boxed end. The nut (.356" OD), which extends out from the rod .79" is captured by a collar welded into the channel. Three plastic spacers keep the rod centered in the channel, while preventing rod buzz.
Most luthiers do not glue in the truss rod, though some choose to epoxy the metal case that comes with the TRMR Martin ™ style rod to the walls of the channel .
It is a good idea to add some silicon caulking to the channel to help prevent against rattling.
Cover the channel with some thin tape so that when you glue you fingerboard down no glue gets on to the truss rod. Some choose to add a wood shim over the square stock instead of using tape.

Re: fretting question

Posted: Tue Sep 29, 2015 1:43 pm
by Barry Daniels
My fretting method is not the Teeter technique. I just open the fret slots a bit to make fret pressing a little easier, and fretboard warping unlikely.