Low end Aria renovation

Construction and repair of Classical Guitar and related instruments
amezcua
Posts: 214
Joined: Tue Oct 04, 2016 9:50 pm

Re: Low end Aria renovation

Post by amezcua » Fri Feb 24, 2017 12:47 am

That`s surprising . Papier mache should have given it Torres sound quality . Only joking . I assumed when I saw the Aria name that anything Japanese would be quality materials and construction . It`s all in the balance at the moment as even a painted rosette might be a way to reduce weight. I hope it has a reasonable sound when I get the braces in .Then I can give it some nice edge bindings. I might get some pricey £2.30 p ones .
I don`t feel guilty about the alterations as I plan to reorganise the frets to give a Kirnberger or Valotti unequal tuning . I use Bostik Contact glue to fix the frets ,with a Korg tuner to get every single note spot on in tune.This will be my second one . I use a dummy fret to find the position and dab of masking tape for the marker. The glue is applied to the fret itself and the fret is fitted straight away holding it with tweezers .You have time to double check the open string and adjust the fretted note before it sets. I had to fold some paper over the string to keep the glue off .It`s easy with some practice. Try a few spare carpentry nails on some scrap wood to see how it all stays in place .
Originally I used thinner brass rod soldered on top of a flat base . A thicker 2mm rod with a small tab soldered to the back edge will be better . You don`t want any rolling when gluing frets . The small tab soldered on the back will make for stability and a better glue contact .Soldering on top of the base made the fret thickness variable. But once you get used to "in tune " tuning there`s no going back .

amezcua
Posts: 214
Joined: Tue Oct 04, 2016 9:50 pm

Re: Low end Aria renovation

Post by amezcua » Sun Feb 26, 2017 1:21 am

The Bridge Doctor is now fitted . Finding the right size drill was the hardest .Then I sharpened it with my new diamond file. I was surprised how close the internal block was to the back brace. Maybe a few credit cards gap. The Allen Key needed was an Imperial size and so none of my metric ones fitted. A plain screwdriver does the job of adjusting . Allen Keys of any size are put on this planet to annoy us.
The top came into shape very easily . The two lampshade reflections became one size again .
Over the bridge area where the strings loop around there was a decorative cover .Black with 2 white edges.Or dark brown with yellowy edges. It was obviously a plastic thing. I lifted an edge and it bent up to show that some cheap rubber glue had been waved at it when manufactured. Not evenly spread but untidy dabs. It split at the edge of the new screw so I removed it and turned in the fixing screw a bit more . A few genuine strips of bone and ebony with hot glue will be better for sound. A bridge is no place for rubber glue and plastic .
Thinking about the reason for the top sagging It was not the fault of the brace pattern so it would be fair to the original design to reinstall four braces close to the original . That`s me backing away from fitting any more than I have to . Four braces plus a sound post bridge doctor won`t seem excessive .

amezcua
Posts: 214
Joined: Tue Oct 04, 2016 9:50 pm

Re: Low end Aria renovation

Post by amezcua » Sun Feb 26, 2017 10:36 am

I skipped over some details of fitting the bridge doctor. The top edge of the wooden part and the nylon rod were tilted at different angles and heights. I laid the Doctor on it`s side and sanded the top edges against a square wooden block . Once the touching surfaces were on the same plane it was time to fit it inside. The fixing screw needs to be a close but sliding fit in the top . If the top is gripping the screw threads it will put up a fight when the nylon post gets tightened . All the surfaces need to fit closely .

amezcua
Posts: 214
Joined: Tue Oct 04, 2016 9:50 pm

Re: Low end Aria renovation

Post by amezcua » Mon Feb 27, 2017 5:37 pm

As it stands the guitar top is flat across .That`s above and below the bridge. The quirky idea of using the size of reflections in the varnish of a lampshade is quite a good guide for judging the levelness of the bridge . The neck on this guitar is nice and straight and it has a new bone bridge. I thought it would be interesting to hear what it sounded like as it is without braces.I only fitted the outer E and e strings. There is plenty of basic guitar character in the sound .Reducing the Bridge Doctor tension made little difference to the sound volume or tone , I brought the top back to it`s flat state again . The effort of twisting the Grub Screw in the wooden block was minimal .I used a plain screwdriver extension bit with no handle (about the thickness of a biro and a similar length ). The twist exerted was between my thumb and first finger reaching inside the soundhole.
A delayed reaction to hearing the sound makes me think it needed to be more instantaneous when plucked. The braces will make that difference I hope. String tension with two strings and the bridge doctor does not alter the top shape .
An adventurous expert luthier might find this setup useful to define what each brace is doing to the sound. An experimental guitar with an open and close soundhole in the bottom bout would make brace changes a lot easier .Something like a screwdown manhole cover would be good .
Intonation generally is far better than when It arrived with a bridge bone that was far too thin . The frets are peculiar . The metal ends have all been shaped to a point. Unlikely to have been a refret job. Most frets stand inside the neck edge and that leaves narrow openings in the wood that are rough on the hand. All easy to correct.

amezcua
Posts: 214
Joined: Tue Oct 04, 2016 9:50 pm

Re: Low end Aria renovation

Post by amezcua » Thu Mar 02, 2017 11:57 pm

I waited for delivery of Titebond 1. Good to know that`s the right one for guitars. I thought hot hide glue for the braces through the soundhole and upside down would be too risky . So clamps or no clamps was the guessing game .
Too much dithering about for a few days waiting for the glue to come. I improvised the fixing method . The longest braces were shaped and I attached each one by using bluetack as a gripper over the back with 2 small bits poking outwards as stabilisers and some to fit between forefinger and middle finger. That gave me a sense of the direction the brace was pointing.The bluetack was near one end to just reach over the crossbar.That was done with the guitar facing downwards and held in one hand..After they were in I reached in to press the centres down. Job done for the longest braces . The shorter side ones will be easier .
If they are not dead symetrical it`s not a disaster . I might add a few short braces in some interesting positions just to see how it works . Using a lamp and mirror when the top is facing downwards is next to useless . I`ll have a look at in the morning .

amezcua
Posts: 214
Joined: Tue Oct 04, 2016 9:50 pm

Re: Low end Aria renovation

Post by amezcua » Sun Mar 05, 2017 1:21 am

The first two braces were perfectly secure and clean. A neat thin glue line along all the edges and at the ends . That was without any clamping with Titebond 1 . Next day I was brave enough to repeat the process. The glueing was not quite so tidy on one. It must have budged sideways as I pressed it down .But they all dried securely . Not as I had planned in my head though . The arrangement of positions seemed a bit offbeat.The first two were meant to be in a fan pattern. One of them was ,on the treble side. The other was dead straight down the middle as near to the bridge doctor as you could get .Second pair I achieved a fan position on the bass side.The last one ended up on the treble side as vertical as the centre one.
It had a full day to set the glue. I put on Savarez medium tensions. The top e string broke at the bridge. I was reusing them .A replacement went in well . The top nylons needed a fair bit of stretching to stay in tune.
The sound really surprised me. I had noticed when tuning how stable the notes were with the tuner. No drifting upwards and confusing me . The top notes have clarity .The lowest string has a good serious Spanish character. Playing a Bach Sarabande was a revelation .Crystal clear chords and just a very beautiful sound.
I`m absolutely chuffed.
Maybe the accidental brace pattern is worth copying. I rounded the tops on the first two .The 3rd and fourth ones were shaped to a point.The bass side angled one was higher at the bottom end and thinner towards the soundhole. I was guessing about the mechanics of how it would flex the top .
Just a total success but it needs some proper dark bindings round the top to replace the daft black paint that overlaps the top edges. It needs more respect than that now . Well done Aria or maybe my accidental braces .

amezcua
Posts: 214
Joined: Tue Oct 04, 2016 9:50 pm

Re: Low end Aria renovation

Post by amezcua » Sun Mar 05, 2017 9:53 pm

The laminated top without braces had very little resonance in itself if I tapped here and there . .The word flabby kept coming to mind. With the bridge doctor taking the strain it left the braces to simply resonate the top free of tensions .That`s maybe why the notes were so stable as I was tuning the strings with the korg orchestral tuner . The top material was (maybe ) behaving in a neutral fashion and allowing the strings to decide on the frequency. My other solid top guitars will most likely be getting some input from their natural wooden stiffness .Some notes on the solid tops start to deviate from the tuner frequency almost as soon as they are plucked .
This Aria has no clunky dead notes like the (my) solid tops have .
The odd one out brace was the vertically placed one near the treble end of the bridge. That might have satisfied my curiosity about the Vicente Tatay braces which are mainly all vertical from the bottom towards the soundhole .

amezcua
Posts: 214
Joined: Tue Oct 04, 2016 9:50 pm

Re: Low end Aria renovation

Post by amezcua » Mon Mar 06, 2017 2:24 pm

First impressions may not be completely accurate so there are a few tiny points I have to put right. There are a couple of notes that drift upwards after plucking . The main one is right at the top of the high e string. One or two others but not enough to be a nuisance . One note produces a nice shimmery effect. That might be when I played a two note chord . It would be nit picking to complain . I like the way the bass notes don`t keep on and on .One youtube guitar with Brazilian Rosewood sounded gorgeous but after a while you just heard those continuous low notes all the time .
Now I will use my capo to shorten the playing scale with reduced string tension for normal tuning .Small hands is always my obstacle . I have a new set of high tensions ready for later .

amezcua
Posts: 214
Joined: Tue Oct 04, 2016 9:50 pm

Re: Low end Aria renovation

Post by amezcua » Tue Mar 07, 2017 7:26 pm

The nut needed checking next and it did seem very untidy .Glue showing around the joins.before removing it I ran a sharp edge around to save anything pulling away . A very slight pressure at the back of the nut made it bend inwards . Tapping it off showed why it was so flexible.There was a hollow slot inside it . About 1/4 inch deep ,full width , testing the depth with the point of a pair of scissors. The plastic is like putty if you use a diamond file on it. The fit was bad .There was uneven glue underneath and mainly on the end of the fretboard. Removing the glue showed a square treble side and an acute angle on the bass side. That left a gap at the bottom.The varnish nearby has managed to creep underneath .The new bone nut was a tiny bit deeper front to back and that disturbed the close contact needed.Cutting and scraping that clear showed how squashy and elastic the varnish was .
The new buffalo bone nut is from China . Are they farming them too? (It`s Water Buffalo and not endangered).
While all the strings were slack I happened to notice I had parked the new bridge bone in the slot upside down . They make a flat groove in the middle as an indicator .I should have gone to Specsavers. { Apparently I had it the right way up but I wanted a straight top and full thickness so it`s now officially upside down }.
So a lot of filing and sanding later the nut and bridge fitted with diluted Titebond --recent information I have read this week ,and I definitely clocked an increase in volume . String clearances are good and the neck is in good shape .
Fortunately I read yesterday that the bridge bone does not need any grooves . I hope that`s true .One job less.
I can`t bear the idea of no grooves so I will make grooves in the lead up curve and end on the same flat top .
The black varnished /painted edges imitating ebony binding will be changed for real ebony soon . The ebony won`t chip away and look scruffy .I have never fitted bindings so tried to find those long rubber bands. There were some reels of elastic tape for not much money ($5) and the cheeky devils tried to add about $50 postage . Right at the end as if I would just push the pay button . They must have worked in a bank .

amezcua
Posts: 214
Joined: Tue Oct 04, 2016 9:50 pm

Re: Low end Aria renovation

Post by amezcua » Mon Mar 13, 2017 12:45 am

A slight horror story as up till now I assumed the guitar had bindings and just a plain wood edge. But the black varnish /paint was all there was.
The paint disguised a short cut in production methods.I had cut away a short section thinking there was an open joint. The end grain of the top had a tough coating of glue or somesuch to make the edge a bit tougher .I have adapted a carpenter`s marking gauge to scribe even lines round the top but that surprised me. So it`s just like a violin purfling job now to fit a nice ebony binding .almost a nice introduction to guitar making for me .More than I had planned but we are developing a good relationship now .

amezcua
Posts: 214
Joined: Tue Oct 04, 2016 9:50 pm

Re: Low end Aria renovation

Post by amezcua » Tue Mar 14, 2017 1:32 pm

Now I have a clearer picture of what a laminated guitar is. This particular one may be very different from other laminated models.The top outer surfaces are made of minutely thin layers of spruce and inside is a much thicker layer at a 90 degree cross direction . The mystery wood has darker bown flecks and if I was to guess I would say it was Rubber Wood. That is found in cheap dining tables and at one time as a tree produced the very important rubber for car tyres etc. When the tree stopped producing rubber it was cut down and burned .Then business pressure found new uses for it .But hey it`s more wooden than Nomex. So a laminate is not always crossed layers of the same kind of wood we admire on the surface .
I am cutting the ledge for an ebony binding for the top now. (By hand tools ). It`s more complicated with so many layers involved. Plus the thin flakey varnish has to be preserved as much as possible. Flakey is the main quality.As the chisel or knife cuts you might see a strip of one inch long separating with no effort at all .
The cutting action needs more care than usual . The easy shaving after a clean cut soon changes to an opposite grain direction . Ultra sharp tools held very lightly seems the best way to do this .As far as possible the cutting movement is vertically into the wood with a short rocking action .A sliding cutting movement would be too dangerous and run off course . Smaller shorter knives and chisels keep it in control . I am almost inventing the right way to do this job . It needs concentration .

amezcua
Posts: 214
Joined: Tue Oct 04, 2016 9:50 pm

Re: Low end Aria renovation

Post by amezcua » Tue Mar 14, 2017 7:23 pm

The tape that I ordered came today . Somewhere I had mixed up sticky type tape and tape to wind around the guitar . A mysterious process that always fascinated me . The tape that came was supposed to be the wind around type. But it`s more like adhesive bandage . No chance of breaking bits off one handed.This needs seriously sharp scissors .So another cotton twill kind is on it`s way . I estimated the length at about 22.5 metres so had to order two rolls . On the bright side I have enough sticky tape to last the rest of my life .That reminds me of my first Casio watch and the battery that lasted ten years . I resented the idea of counting out my life with watch batteries .

amezcua
Posts: 214
Joined: Tue Oct 04, 2016 9:50 pm

Re: Low end Aria renovation

Post by amezcua » Fri Mar 17, 2017 10:37 pm

Today a red card to tell me my binding tape is ready for collection . This is 3/4 inch woven cotton . The tacky bandage -like tape is one inch wide so careful spacing will keep the glue off the cotton tape .I have another reel of fibre glass reinforced tape .There is so little information on the envelope it`s hard to tell who sent it . I seem to be getting sticky tape amnesia with these unfamiliar products . The tacky bandage sticks very firmly and I tried a bit for 24 hours and the varnish is still fine.
This week has been concreting fence posts after the storm last week so it slowed my progress and splintered my middle fingernail . But my nails grow quite fast .

amezcua
Posts: 214
Joined: Tue Oct 04, 2016 9:50 pm

Re: Low end Aria renovation

Post by amezcua » Wed Mar 22, 2017 11:22 pm

The tape that looks like a bandage with adhesive is totally useless for bindings . I shaped the first ebony strip on the violin rib bender . Just as a dry practice run I put the strip in place with the "bandage". The slighest flex in the ends was enough to make it come apart within an hour. Even the unstressed tapes on the sides peeled away from the tape end first. It won`t really stick to varnish .So I used the clear tape with reinforcemnt strips . That stayed in place overnight with no separation .
The ebony has a tendency to run offline when heated and bent . I thought to leave it near the final shape and taped in position for a while and then get it more exact before gluing . Titebond seems the best way but one youtube maker uses a hairdryer to keep the hide glue fluid after the taping . I liked his confidence but he dropped something on the floor so he might have cheated . Also the gluepot was a long way from where he needed it . He had time to wipe and clean as he worked .Quite impressed with that overall .

amezcua
Posts: 214
Joined: Tue Oct 04, 2016 9:50 pm

Re: Low end Aria renovation

Post by amezcua » Sun Mar 26, 2017 12:35 am

Some delays in cutting the channel for the top binding. One was erecting the garden fence after the storm and then learning the subtle arts of laying large travertine tiles in the kitchen . While doing that the tape was holding the ebony strip in position . The groove needed more accurate cutting so I did that today . Most useful tool was a 1/4 inch chisel with no side bevels and held like a pen. But what a difficult and fragile job to be cutting into two laminated surfaces . The side laminations are ,on the outer layer just 1/4 mm thick. Top and back total thickness is 3 mm . But the inner layer of the sides crumbles to dust as it`s cut .And the grain direction is continually changing. If it was a biscuit I would not mention that .The channel will need some glue in it to consolidate what`s there. Too much end grain and fresh air to hold onto a cold strip of ebony .
There is a method of gluing cello plates with hot hide glue.The surfaces are both pre coated with glue and then they are reheated as the parts are connected . As I have shaped the ebony into the curves it can hold it`s position with just 5 tape pieces.
I used a heat lamp on violin bows once to regain the correct camber .That just needed to imitate the temperature in the back seat of a car in the sun .Perfectly safe and reliable. Maybe a preglued strip warmed up with the shaft of a soldering iron would make the warming up more effective. Piano technicians have special heaters to iron the felt hammers . More manageable than a flatiron . What would the drill be ? Glue channel and strip .Put to one side.Then put together with 5 tape strips . Heat sections with soldering iron and apply fresh tape as it melts. No wiping or cleaning needed . Get the binding tapes on (Fast ) and warm again with a hair dryer as you double check the fit.
Is it possible to melt glue through 2 mm thick ebony. Remember the glue pot is not strictly needed at this stage. and no wiping or cleaning. Can you fit a metal (brass ?)feeler gauge thickness onto a soldering iron tip . Over 60 degrees will damage the glue. It could slide in between to melt the glue. Time for some basic glue experiments on offcuts .

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