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Need some help. Fretting board before glueing to neck blank
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Author:  Rod True [ Sun Feb 24, 2008 5:57 pm ]
Post subject:  Need some help. Fretting board before glueing to neck blank
OK, so Mario, Rick, JJ and Hesh have all recently convinced me that it's better to fret the fretboard prior to gluing it onto the neck.

So here is what I've done, in order and the results.

make the fretboard (slot, taper, bind, profile to 16", ensure bottom is flat)
fret the fretboard (leaving the 3rd and 13th out for the locater pins)
after fretting the board, I made sure that the bottom of the board is still flat as well as the top side (frets)
pre-shape the neck to thickness, rough width/taper (within 1/16") and flat along the gluing surface (it was about 0.010" back bowed, didn't think this would be an issue).
I than clamped the fretboard onto the neck to drill the locater pins. With the clamps on I checked again for level frets and all looked good (still the 0.010" backbow but again didn't think it would be an issue)

To glue I used Lee Valley G1 epoxy which is classified as follows,

G1 (1:1 ratio) was developed for use on wooden airframes and offers long working time at high temperatures (recommended for use at 20°C/70°F or over; working time is 60 minutes and cure time is 24 hours). It is the system of choice for projects where large areas are to be glued and when maximum fatigue resistance is required (for skis, golf clubs, etc.).

The temperature in the shop was 73*

Now when I made my new radius sanding blocks, I made one as a clamping caul for gluing on the fret board in this manner. I cut slots in the locations of the frets with the remainder to bare down on the fretboard surface when clamping.

So here is my glue up,

Table saw/3/4" granite/1-1/4" clamping caul/fretboard/neck

I mixed the epoxy as per the specs (1:1 measured by weight) for a good 5 mins to make sure it was totally mixed, than I applied the glue to the fretboard, placed the neck on and clamped it down with 9 clamps total. I left it for 12 hours, than unclamped just to pull the locater pins, than I reclamped and left it for another 24 hours.

Now the frets are not level [headinwall] there is back bow between the 7th and 8th fret of about 1/32" along the length of the fretboard. (the truss rod is an Allied double action and it was not tightened one way or the other).

I'm sure I did something wrong but I don't know what or what to do now. I'm thinking that I'll have to pull the frets and level the board and refret.

Can someone help me please?
Author:  jerr6 [ Sun Feb 24, 2008 7:21 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
maybe the caul had slight curve causing back bow. will the truss rod correct it?
Author:  David Collins [ Sun Feb 24, 2008 7:37 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
Rod True wrote:
I'm sure I did something wrong but I don't know what or what to do now.


I think what you did wrong was to try to put the frets in before final assembly..... (I wish there was an emoticon that meant "sorry, I'm really not trying to sound like an a**").

Some folks say they can pull off fretting a board off the neck, and I'm sure some of those folks actually do. ;) I've always been against it for small builders though, as most already know I'm sure. This is one small example of about 483 (rough estimate) small things that can change, shift, flex, swell, etc., from the raw board to the assembled instrument. Leaving fretting to the very end allows all these variables to be eliminated by the final board leveling before fretting, after the neck is glued on. I know you can get fine results with pre-fretting, but I would be very surprised to see someone get there without doing a good number of practice necks to refine the procedure and work out any bugs.

For now, I would keep building until you can get strings on it, see where string tension and truss rod action will bring you. Then if it is still too much to true up out of the frets themselves I would pull the frets and re-level the board. As of now though I wouldn't worry about it too much, as it seems there's no reason to pull them right away.
Author:  Hesh [ Sun Feb 24, 2008 7:47 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
Rod bro you just gave the most comprehensive situation report that I have ever see on the OLF - thank You - it's a pleasure to have so many possible questions answered in advance.

First off I am not convinced that fretting the fret board off the neck works for me. I know it works for Mario and perhaps I probably don't have the method that he uses down correctly. My last guitar, Anthony's, was fretted after I epoxied the fret board onto the neck and leveled the fret board allowing for a .016 drop off at the sound hole.

Here are some things to consider. Fretting the fretboard off the neck, or on for that matter, induces some back bow. My tests show the back bow is halved if you pressed you frets over hammering. Your neck had .010 back bow in it already.

If, and I say if, when you clamped the fret board to the neck you did not use at least 4 evenly spaced clamps favoring to clamp the ends the back bow in the fretted fret board would now be built-in to the already slightly back bowed neck. Which ever had more back bow would encourage the other for further back bow.

Another way of saying what I am trying to say is if your locater pins were drilled with out complete flat contact of the back bowed (because it was pre-fretted) fret board the locater pins would be to close to each other further creating back bow in the glued up assembly.

What frets did you use height wise because you just may be able to tweak the truss rod and relevel the frets?

Lastly - I got reamed out here for not applying the epoxy to both the neck and the fret board and some advocated a thickened filler layer which I think is over kill for a fret board and best left to boat building. But even though I don't think that you will have a problem the next time I epoxy a fret board I will put the epoxy on both the neck and the fretboard.

I hope something here might help bro.
Author:  grumpy [ Sun Feb 24, 2008 7:58 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
Just keep building it. The strings will likely pull the relief into it.

You have to have it flat. No damned backbow. Press the backbow out. And don't leave any frets out; that defeats the entire purpose... Drill for your locating pins well ahead of time, and use short ones. Leave the stupid things in the damned neck.
Author:  SteveCourtright [ Sun Feb 24, 2008 8:02 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
Rod, I can sympathize. This happened to me, too, but my fretted fretboard had about 1/4" of backward bias showing before gluing onto my neck. I could easily press the board down with a finger, so I thought it would stay flat when combined with the (stiffer) neck. I was wrong. Had to take off the frets, level the bump and refret.

I am looking forward to seeing what the experts say about your scenario.
Author:  Rich Schnee [ Sun Feb 24, 2008 9:24 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
Frets will do two things when pressed into the slots. They either compress the wood on either side of the tang or they push the wood away making the slot wider. There is some degree of both of these actions when fretting a fingerboard. If the fingerboard is not sufficiently stiff when you press the frets in it will do more pushing and less compressing, this will cause the fingerboard to rise up. If the pressure applied to the fret is not even you could get compression along part of the fret and the wedging affect on the other. This will cause a twist if you consistently do it to enough frets. I suspect that the problem started when you fretted the fingerboard. I don’t think gluing the fingerboard to the neck is sufficient enough pressure to compress the wood along the tangs.

I am no expert on the subject so if anyone doesn’t follow what I am saying and thinks I am off base here, please let me know and I will gladly remove this post.
Author:  Hesh [ Sun Feb 24, 2008 9:51 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
I wanted to add something and please forgive the partial high-jack Rod buddy.

I did a test a couple of years ago and fretted two fret boards one with the frets pressed and the other with the frets hammered. I can't find the picture at the moment of the hammered board but the pressed board had half the back bow of the hammered board.

Attachment:
DSCN2295.jpg


Also Mario wrote a great article in Guitar Maker about a year ago where he detailed his fretting off the neck system. One of the things that he would do, if I remember this correctly, was suspend the fretted board at both ends over night with a weight in the middle. This was to flatten any back bow out and it also I think helped seat the fret tangs better too.

Please correctly me Mario if I have this wrong I am running on memory alone here.
Author:  JJ Donohue [ Sun Feb 24, 2008 10:19 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
My last 8 FBs were pre-fretted prior to gluing onto the neck. There was no backbow and the frets were reasonably level after gluing. And to top it off, I left the damned pins in and had to heat them with a soldereing iron so I could pull them out the next day! I guess I didn't realize it would cause a problem.

So why didn't I get any backbow? Here's my theory:
...when I slotted with Shanes blade (.024"), the board was flat and square
...after putting on the radius, I always have to deepen the slots because the ends are now too shallow. So I do this with the SM handsaw (.022") to make sure the slot is deep enough for the fretwire.
...Before installing frets, I put a generous opening on the top of each slot with a triangular file.
...Lately, I've been pounding in the frets...I noticed absolutely no difference having used the press method on half of my FBs. Pounding is faster and I feel more in control.
...Before pounding them in, I place a line of LMI white glue into the slot. The wire slides in nicely as the glue acts as a lubricant.
...Once all frets are in (except for #1 and #13 where the damned pins go) I clamp the fretted FB to my bench overnight.
...Next day all is flat and it's ready to be epoxied to the neck. I've used epoxy on all but 1 neck. On that one I used HHG and got severe backbow. That was on #001 5 years ago and I got reamed by guess who? [headinwall]
...After removing the clamps, I go through a preliminary leveling with 220 grit on a flat plane bottom. After it is attached to the body and the fb extension glued down, I do the final leveling, crowning and polishing.

Is it just possible that the enlargement of the slot caused by the handsaw as well as filing the tops of the slots has somehow helped to relieve any stress that otherwise conspires to produce backbow? It has worked for me each time and will continue unless I can find something better.

Rod, I too would string it up as before making a decision on whether you need to remove frets.
Author:  grumpy [ Sun Feb 24, 2008 11:30 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
I seem to have struck some damned nerves with my damned comments! [:Y:] [:Y:]

<bg>

Sorry 'bout that folks; I was just a little, oh, frustrated at David's chiming-in with the 438 ways to screw up post. I'm sorry Dave, but this method works flawlessly for me now, and works for Martin and other makers as well.

Yes, after fretting, I force a bow into the fretboard by clamping it with a 1/2" block at each end. I leave it like that as long as I can, overnight usually. The next day, it'll likely still be bowed, but a little flexing will bring it dead flat. What this seems to do is press the tangs into the fretboard by applying side pressure.

I also use glue when fretting, used to use white, but now use liquid hide glue(fish glue'd be fine, as is hot hide). The glue allows the fret to just slide in place, almost with a click, and once hardened, adds to the structure.

Why are you guy pulling the alignment pins out!?! Use little wee short pins, and leave them in. I use little finishing nails as my pins for all alignments; they are exactly 1/16" dia, so a 1/16" drill bit works perfectly, and being mild steel, the nails cut readily with even the cheapest of side cutters... Drill through the fret slots like you already to. then tap the nail into the neck, and snip it off leaving only about 3/32" proud. That's all you need to hold it in place. Won't harm a thing to leave them in place forever...
Author:  grumpy [ Sun Feb 24, 2008 11:31 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
I seem to have struck some damned nerves with my damned comments! [:Y:] [:Y:]

<bg>

Sorry 'bout that folks; I was just a little, oh, frustrated at David's chiming-in with the 438 ways to screw up post. I'm sorry Dave, but this method works flawlessly for me now, and works for Martin and other makers as well.

Yes, after fretting, I force a bow into the fretboard by clamping it with a 1/2" block at each end. I leave it like that as long as I can, overnight usually. The next day, it'll likely still be bowed, but a little flexing will bring it dead flat. What this seems to do is press the tangs into the fretboard by applying side pressure.

I also use glue when fretting, used to use white, but now use liquid hide glue(fish glue'd be fine, as is hot hide). The glue allows the fret to just slide in place, almost with a click, and once hardened, adds to the structure.

Why are you guy pulling the alignment pins out!?! Use little wee short pins, and leave them in. I use little finishing nails as my pins for all alignments; they are exactly 1/16" dia, so a 1/16" drill bit works perfectly, and being mild steel, the nails cut readily with even the cheapest of side cutters... Drill through the fret slots like you already to. then tap the nail into the neck, and snip it off leaving only about 3/32" proud. That's all you need to hold it in place. Won't harm a thing to leave them in place forever...
Author:  Rod True [ Sun Feb 24, 2008 11:50 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
Cool, thanks for all the replys folks, I've read them all and I believe I'll just keep going. We'll see what the pull of the strings do before I worry to much about leveling or pulling the frets.

Thanks again, a couple more weeks and I'll post finished pictures.
Author:  Ken Franklin [ Mon Feb 25, 2008 1:15 am ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
Another advantage of HHG for the frets might be that it shrinks when it dries. Hey Mario, do you use epoxy to glue the fretboard to the neck?
Author:  David Collins [ Mon Feb 25, 2008 9:35 am ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
I'm not trying to discredit anyone's methods or say that anyone's procedures don't work. This is just my experience.

One thing I've learned while teaching is that for every one thing I could possibly think of that could go wrong, there are twenty some things I never could have imagined. Second is that I have and still do see a whole lot of small builder's and enthusiasts bring in their instruments, and had to appraise a good regular flow of these at Elderly's. I've regularly found that fret and board issues which would have been eliminated in a final leveling after assembly are one of the most common problems. Even in otherwise great instruments, fret work and setup are what I see most often suffer.

Mario, I'm glad for you that this seems like an absurd topic waste any time over. It's worked flawlessly for you, though I disagree about results being consistently flawless in factories like Martin and Gibson. Maybe you can't figure out how people could have problems here and I can't figure all the causes either, but it does seem to be one of the more common issues I find.

For small builders who may not have the clamps, cauls, patterns, and procedures quite so nailed down though, I find unexpected problems should be expected. Fretting after final assembly simply allows for a final check and truing of the board should any unexpected twists or humps occur. It takes more tools, might take a half hour more of labor, and any time you're working with hammers and cutters around the instrument it will leave you at higher risk of scratches and dings. My solution is to buy the tools, take the extra half hour, lay out covers and be careful with your tools, and it's usually worth insuring that the board is level. Or if fretting first has always worked fine for you, great, do that.

That's my experience, my approach, my opinion. Everyone else can use whatever works for them though, and it really doesn't matter to me.
Author:  JJ Donohue [ Mon Feb 25, 2008 9:52 am ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
No problem here David. Keep chiming in as to your vast experience and comments that are meant to make us all better builders.

Thanks to guys like you and Mario who give so freely! [clap] [clap] [clap]
Author:  grumpy [ Mon Feb 25, 2008 10:24 am ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
The issue is that Rod is trying a method, had a question, and you chimed-in with little help, only unnecessary discouragement.
Author:  crich [ Mon Feb 25, 2008 10:45 am ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
Stupid question, if you fret before glueing, does your clamping have 20 slots in it to receive the frets? Clinton
Author:  grumpy [ Mon Feb 25, 2008 10:53 am ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
no
Author:  Kent Chasson [ Mon Feb 25, 2008 12:29 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
David's point is a good one. I've gotten great results pre-fretting but it took awhile. And I still run into unexpected problems.

One thing that helped me was using a caul on the back of the neck to help even out the clamping pressure. You still have the transition from the neck to the heel to deal with. I'd be curious to hear ideas on how to keep the clamping pressure even in that transition.
Author:  Hesh [ Mon Feb 25, 2008 12:43 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
Lance can we please have the popcorn eating emoticon loaded? :D

I also agree that David's points are most helpful, welcome, and on-topic. None of us should be fretting over this issue...... :D [xx(] :lol:
Author:  Rod True [ Mon Feb 25, 2008 1:16 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
Clinton, I made one of my radius blocks with slots to fit over the frets, but there aren't 20 of them as the block is only 16" long, it does cover everything over the neck and more though.

I've been thinking about my problem a bit more and I've come up with one idea that may have caused me the grief.

When I clamped everything down, I used a total of 9 clamps, 7 cam clamps and 2 "F" style bar clamps, one at the nut end and one over the heal.

I placed the two outside clamps with light pressure, than starting at the nut end, I place each of the cam clamps till I reached the curve at the heal, all of them were evenly spaced out. I worked my way back and forth every other clamp tightening (cam clamps don't offer much finesse when adding pressure though) sort of like lug nuts on a wheel. I tried to make sure the pressure was even along the length of the neck but I could have tightened one section down more than another which might have caused me grief.

The other thing is I'm wondering if some part of my set up is not flat enough (dead flat) which would also cause me grief and just accentuate the back bow that was already in the neck.

I'll be looking for that article that your wrote Mario for Guitarmaker (I don't have that issue) and checking it out. I like this method and would like to stick with it and see if I can get it right. I'm certainly not giving up on it just yet :)
Author:  crich [ Mon Feb 25, 2008 2:54 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
If you find that article, let us know which issue. I tried contacting A.S.I.A,no return on my emails or phone calls. [headinwall] My user name doesn't work and I want to renew my subscription. Clinton
Author:  grumpy [ Mon Feb 25, 2008 3:23 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
I don't think there's anything in the article that I haven't, or can't, discuss here. Just ask....
Author:  Rod True [ Mon Feb 25, 2008 4:01 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
I think I have questions but sort of don't know what they are (does that make sense?)

Any chance you'd do a tutorial of your procedure Mario? I know I'd sure be interested.

Anyway, the procedure that I layed out above was what I thought would get me there, obviously not.

Dead Level is the key right? If it isn't dead level, don't glue the board onto the neck till it is? Am I right in this assumption?
Author:  grumpy [ Mon Feb 25, 2008 4:13 pm ]
Post subject:  Re: Need some help. Fretting board before glueing to neck blank
I think your method was fine, just needs refining. The more true everything is, the more true the outcome. If you consistently encounter some backbow, and it's consitent, modify your caul by shimming it the same amount.

Stay consitent; use the same caul, same clamps, same glues, etc..., time after time, and work out whatever inconsistencies arise mechanically.
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