Removing Contact Glue on a fretboard with a Soldering Iron .

Construction and repair of Classical Guitar and related instruments
amezcua
Posts: 339
Joined: Tue Oct 04, 2016 9:50 pm

Removing Contact Glue on a fretboard with a Soldering Iron .

Post by amezcua » Thu Jul 20, 2017 1:08 am

This is a technical tip if you are like me and enjoy attaching out of line frets to the fretboard using contact adhesive . These frets are 2mm thick cylindrical brass and I have used evo stick to place them with a Korg Orchestral Tuner. My first attempt was Kirnberger III and that was very succesfull musically . On a different guitar I wanted to try the Thomas Young temperament . I also thought it would be useful to start with a straight across fret at the octave .However that idea has been pushed aside as the Young fret spacing was more likely to reduce the out of lineness of the frets . I placed the whole set first up to octave level and noticed that b and g string could line up much better with the e and E strings. Both e and E spacing is pretty much identical . { I have abandoned the idea of a straight nut to allow flexibility in string length .}
Here is a little bizarre twist I came up with and not a joke btw .I bought a few yards of white knicker elastic. Tied around the string at the bridge and gently stretched down past the nut . Then ,with a biro ,I marked the fret positions I had tuned in . By increasing the stretch the positions rearange themselves to give a quick comparison with e and E string frets . It showed the Young temperament is less notchy than the Kirnberger and out of line frets will hardly be noticed by a player .
So now I had the job of repositioning those b and g frets . Pliers can twist the short frets to and fro to release them .They don`t want to come off but it`s not a real struggle . Most of the adhesive patches remains on the fretboard .Not a huge amount but I did not want to start scraping . There is a volatile adhesive cleaner made by Evostick but it is very stinky and flameable and not what I would like to use .
So the little technical breakthrough ocurred to me. Try a Soldering Iron . The action developed very naturally . In my left hand I had a small 5mm wide screwdriver. I used a dragging action on the evo stick and a light scribbling action with the soldering iron where the glue was clinging to the wood. It peeled back very easily .Just concentrate on the edge and keep it pulled back with the screwdriver . The soldering tip is a blunt rounded point like a pencil tip .It makes a light quick contact and does no damage to the wood .The smell is not too bad and the adhesive turns into a tiny rubbery ball that blows away .
Now If I make any mistakes in tuning I can put it right easily .
This is ideal for one offs for myself . If a Laser machine was handy all the positions could be cut out automatically and traditional style short fret pieces could be fitted .Then the finished fretboard would be glued onto the guitar .

amezcua
Posts: 339
Joined: Tue Oct 04, 2016 9:50 pm

Re: Removing Contact Glue on a fretboard with a Soldering Iron .

Post by amezcua » Sat Jul 22, 2017 9:44 am

The bizarre idea of using knicker elastic to roughly estimate where frets would land if I altered the nut position (for that string ) is maybe similar to a sailor wetting his finger and holding it up in the wind to test wind direction . Not exactly accurate but a useful indicator .
Perfectly straight frets will not be possible with an irregular temperament but getting the closest possible positioning will make the guitar more player friendly .The tuning will always follow the Korg Tuner or any other tuner programmed for temperaments. Once the notes are established there is no need to adjust the bridge or nut. The string brand used in the tuning process will give the optimum accuracy so make your choice beforehand . Don`t tune it all up and then change to totally different strings . It will still work but it`s best to mention that .
Just to remind anyone trying the soldering iron trick . The iron is easily hot enough to burn a hole in the fretboard if you keep it in contact. Just keep it moving with a light touch .If you ever stripped paint off a door with a hot air gun you need to be aware of the danger of burning the wood .I can peel off all the paint on a panelled door without any scorch marks so I may have an unfair advantage over you . That just takes practice and thought .
The choice of Thomas Young temperament was influenced by a pianist writing about having his piano tuned in Young and his point that Thirds which are especially good in that tuning . The Thirds are at the centre of chords and that is what seemed ,to me ,ideal for guitars as well as pianos .

amezcua
Posts: 339
Joined: Tue Oct 04, 2016 9:50 pm

Re: Removing Contact Glue on a fretboard with a Soldering Iron .

Post by amezcua » Sat Jul 29, 2017 1:02 am

Before I placed the brass frets with contact glue I expected the frets to be out of line compared with ET. But I started by placing one straight fret at the octave position. It was impossible to forecast where all the frets would land . I had done one tuning with Kirnberger III but the Young temperament is much less out of line than I expected. The Varied spacing along any single string can be seen but I was surprised how close each string pattern was to it`s neighbour. So I stopped mid way through and abandoned the straight octave . I relaid a few lines of notes to get the cross pattern as tidy as possible . I wish there was a computer way to sort this out .
The guitar I am altering was very cheap and the tone is nothing special but with notes so well in tune it is more satisfying to hear and chords have more clarity and crispness.
I did notice if I checked the exact notes on the tuner that finger pressure will vary the needle position and more often than not my fingers will produce a note slightly higher than I set it . About ten degrees sharp on the needle . Maybe I should check against the correct open note first and then set the new notes slightly flat.Then they will play better when it all comes together . I`m still on a learning curve .
With 2mmm brass rod as frets there are many that are level or substantially overlapping . That would give about plus or minus one millimetre. I was not careful enough with the width on some and need to replace the few where the string can drop off the fret. I filed the fret flat then lighly bevelled the edges . It`s not too hard with Stewmac type magnifiers and a molegrip to hold the fret .
The hardest part of this is contact glue stringing and getting the top back on the tube every time. Magnifiers and watchmakers tweezers is the way to go .

amezcua
Posts: 339
Joined: Tue Oct 04, 2016 9:50 pm

Re: Removing Contact Glue on a fretboard with a Soldering Iron .

Post by amezcua » Mon Jul 31, 2017 1:12 pm

Brass frets are fine if you want them straight . As a metal it is more awkward than steel . It does not behave in the same way .One of the treatments to make brass more pliable is to heat it up till it goes black and then quench it in cold water. That`s basically what annealing is . That would make steel more brittle but it makes brass more pliable. But in any case the shape of a wriggly fret across the fretboard would have to be calculated the hard way which is what I am doing now .
Another approach is to have separate fret pieces and work out a filler between the pieces . I thought of Araldite and then looked up resin metal repair mixtures . I used one of those resins to make a pulley once . It drove a drilling frame from an old dishwasher motor. The rubber belt did not wear it away .
Knowing which way each piece fitted next to it`s neighbour would allow an angled cut with filler between to stop the strings catching.
So this is a good way to iron out the fiddly details to look after the strings. I have never used string bending myself and I was surprised how much the strings move sideways . Gaps between frets is something to sort out . Having very fine close contact would still produce a damaging edge for nylon strings

amezcua
Posts: 339
Joined: Tue Oct 04, 2016 9:50 pm

Re: Removing Contact Glue on a fretboard with a Soldering Iron .

Post by amezcua » Thu Aug 03, 2017 10:02 pm

I ordered a roll of 2mm bronze wire this week . I want to compare it with brass . In the back of my mind was the thought of making full width frets with the different positions .(Wiggly frets). But the bronze may be as awkward to reshape as the brass. After a few days the idea of full width frets seems like a bad idea. It will mean adjustment or replacement will cause a huge disturbance . A single fret can be extracted and changed very quickly . But bronze is harder than brass and is less likely to corrode .2 good points. So eliminating small gaps between frets is the gremlin to destroy. In the last few minutes I thought a blob of Titebond 1 would be worth a try. It sets quite firm. levelling will be easy and it can be reapplied any time you want .A few pieces of masking tape either side of the frets will keep it in the right place as it sets. Titebond would probably break away for attaching the frets due to temperature changes and would be too slow to set. Contact glue clings on and is very elastic . That is showing that all the job has aspects that might change if a better alternative arises .
Trying the new layout all I noticed was how short my nails were and the few times strings got hooked up . The gaps were due to me thinking solely of the tuning aspect . Part the way through that job I clunkilly realised I should have drawn lines between the strings to show where the frets stopped and started . Lesson learned . Not an obstacle going forwards though .
It`s a bit like landing on a strange planet doing this. Things are not always exactly as you expected . One such thing is the spacing for the e and E strings. The proportions are the same but the low E would be better closed up slightly to come more in line with the A string frets.It might make the low E about 1/4 inch shorter at the nut end . The general idea is to minimise positional differences in adjacent strings . It`s a fairly obvious impression visually which just makes sense . None of this involves cheating the Korg tuner . That decides what the note frequencies are . Everything else will follow that rule .
Already I seem to be guessing that Kirnberger III is better than Young (for me ) but we will have to see . Work though it and see what comes out .

amezcua
Posts: 339
Joined: Tue Oct 04, 2016 9:50 pm

Re: Removing Contact Glue on a fretboard with a Soldering Iron .

Post by amezcua » Thu Aug 03, 2017 10:18 pm

I make a point of mentioning mistakes I made .The first one was starting on the top e string. That involves making sure the fret ends are smooth .Not sharp and jagged like mine were .I started by cutting the brass wire (rod) with electricians cutters . In a closeup picture of the brass the cutters squeeze directly together and not like scissors .The edges press inwards and leave a rough central ridge with sharp ends. I learned to hold each fret in a molegrip and filed the ends flat .Then lightly bevelled the edges with a fine diamond file .The routine was easy once I practised it . That would be ok for the internal joins.The edges needed to be filed at a slant and finished with a fine diamond file .That file leaves a shiny smooth surface as if it was polished . Gluing in position set back a tiny bit from the edge made the neck very comfortable .
A lot of this fiddly work should be done wearing magnifiers as in Stewmac pictures . I have a clip on for my specs but they keep trying to pull my glasses off .Time for a search on e bay .

amezcua
Posts: 339
Joined: Tue Oct 04, 2016 9:50 pm

Re: Removing Contact Glue on a fretboard with a Soldering Iron .

Post by amezcua » Sat Aug 05, 2017 11:17 pm

As each day goes by further twists occur in the fret saga . Brass or Bronze ? Not a crucial choice .Either will do ? Separate frets or bent ones to fit right across? Currently the separate frets are winning . Todays experiment is to close a gap between two frets with a blob og Titebond 1 . A small patch of Bluetack either side of the gap and using a pointed stick to make sure the glue will fill the space without any air bubbles. Titebond dries hard and smooth . Would a string with one finger pressing down make any impression on it ?I don`t think so . I will see how it looks tommorrow. With all the frets in place up to the octave position I have not needed to level the frets. There has been no buzzing .One thing I always do when gluing a fret is tio make sure the fret is pressed down firmly after any alterations .
I could remove those frets with gaps between themand replace them --but the twist today is --a small gap will allow the Titebond more stability. A close fitting pair of frets will see the Titebond maybe peeling off . This gets down to the details that will make or break the idea of seperate frets .
Bad news in a way is that I have no idea whether a Capo will work with these temperaments. Swings and roundabouts . Not really a mistake .Just one of those things.

amezcua
Posts: 339
Joined: Tue Oct 04, 2016 9:50 pm

Re: Removing Contact Glue on a fretboard with a Soldering Iron .

Post by amezcua » Tue Aug 08, 2017 12:19 am

I was uncertain about using a Capo but I cannot see any reason to worry about it. The notes are just as valid and a capo will sit between the frets in the same way.One millimetre here or there is no problem .
The attempt to use Titebond glue as a filler between frets was a complete washout . When it all dried I picked away the bluetack and it had got underneath the glue. It all came adrift and I was back where I started.
The best way forward is to carefully draw lines between the strings . I simply drew lines on the fretboard with a biro .When tuning the notes just ensure the line is followed at both sides (or ends ) .The frets become longer as you approach the bridge so they cannot be chopped out all at once .
The detail to watch is to file the ends cleanly with the steel file and use the fine diamond file to make a very thin bevel to remove any sharpness that might snag a nylon string. So that is a small change as I was making the bevel with the steel file . The diamond file gives a polished finish with little effort . A shallow angled thin bevel will ensure the strings will not hang on the fret joins .
Having done this a couple of times has given me a chance to work out my makeshift "rules."
Once the spacing pattern for each string is discovered using the tuner it can be condensed in a more mathematical way .
For example ,take a sheet of paper large enough for a full sized fretboard . Mark the fret positions vertically on the left side of the sheet and continue the string length up to the bridge . Then mark a point on the right side half way up the sheet. (This page will be for one single string . ) Draw straight lines from each fret position across to the single point on the right side . Now you can draw a vertical line cutting those slanting cross lines to show positions for any shorter string length you like The shorter string will be a vertical line between the top and bottom slanting lines .
The proportions will be correct . It`s how perspective works .

amezcua
Posts: 339
Joined: Tue Oct 04, 2016 9:50 pm

Re: Removing Contact Glue on a fretboard with a Soldering Iron .

Post by amezcua » Thu Aug 17, 2017 9:08 pm

Due to interruptions with other stuff I had better sum up the overall point of this subject in case I am interrupted further .
The Basic Point is ; Unequal Temperaments on a guitar are indeed possible and without moving catgut up and down the neck .
[1] My first attempt kept the nut where it was and the bridge has never moved. Leave the bridge where it always is .
[2] Second attempt ---Make the octave frets in a straight line and see where the nut line changes .( 6 fret pieces as the nut positions ) That idea was abandoned mid stream in favour of [3]
[3] Attempt to position frets "as straight as possible" in the middle of the most used part of the fretboard . That made it necessary to remove a few lines of frets and shift them around and not worry what happened to the nuts. In the case of the Young Temperament I feel as if it was almost designed to minimise the out of line frets . That`s just a gut feeling . ( Is that an old pun ? ).
So I have tried to reduce the appearance of wobbly frets . Apart from using contact glue , and not in the way the glue was designed the shiny pristine appearance of the neck will be trashed but not beyond renovation . Anyway it`s possible so it`s been recorded here .(Before they drop the bombs ).

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