rémy a écrit : sam. 24 août 2019 12:59
Olix a écrit : sam. 24 août 2019 11:52
Ma Martin Junior est totalement mate, c'est beau (je trouve) et ça résiste mieux aux coups éventuels !
Je me pose la question sur ce procédé "huilée". Y a t'il un bouche pore avant cette finition ou pas? Difficile de savoir.....
Il y a plusieurs camps sur cette question. La plupart des guitars "huilés" utilisent un "poly blend", donc un mélange de l'huile avec du polymère, qui sert à boucher les pores (comme Tru-Oil par exemple).
Les huiles "pures" sont assez déconseille pour une guitare acoustique. Le bois s'imbibe de l'huile et donc ruine une partie du son, qui devient un peu étouffé. Puis, chaque petite rayure va directement dans le bois et abîme l'instrument. Et attention: c'est irréversible! Une fois le bois imbibé de l'huile il y a aucun moyen de le faire sortir... Si au final cela ne convient pas - faut changer l'instrument
L'essentiel c'est de bien, mais vraiment bien préparer la surface et mettre assez de très fines couches, les luthiers en mettent entre 4 et 20+ pour obtenir l'aspect qu'ils désirent. Les plus il y a des couches, le plus la finition devient légèrement ambrée. Beaucoup de monde utilise une fine couche de gomme-laque pour fermer les pores pour éviter que l'huile pénètre le bois.
Ici un bon avis (en anglais) des étappes pour une finition avec Tru-Oil, et même lui utilise toujours une base de gomme-laque (shellac):
The key to a good TruOil finish, just like most, is good surface prep.
The difference is you can and should go much further in the surface prep, up to at least 400 grit, I use 800 grit for tops and other non-porous woods, instead of stopping at 220 grit. TruOil does not have the adhesion problems that lacquer does on surfaces smoother than 220.
Twelve coats is a minimum, usually 20 or 30 are required.
I seal the pores with shellac, and then sand back to bare wood.The pores don't have to be completely filled, but a couple of coats of shellac will seal them so that it only takes half as many coats of TruOil to fill the pores, and the initial coats dry faster. Be sure to sand back to bare wood, any shellac on the surface will show in the final finish. You can also leave a coat of shellac over the entire surface if you prefer the way that looks. TruOil has close to the same refractive index as wood, so you can see "into" the wood. Shellac leaves a slightly veiled look under TruOil. You can and should go much smoother in your prep work with TruOil, at least 400 grit and maybe as high as 1000, depending on the wood. Some finishes have adhesion issues on that smooth a surface, but TruOil works fine and sometimes that additional smoothness brings out more of the figure.
I warm the oil before applying by holding the bottle under hot running water for a few minutes so that the oil is warm to the touch, I'm guessing 110°F. On your forefinger place a drop of oil about the size of the white prosperous on a wooden kitchen match. Lay your finger on the guitar and make tiny circles as you expand the circle let your finger return to the spot you started as that will be where the largest amount of that drop will stay. You will tell by the feel when you need to get another drop of oil on your finger. Before reloading take your finger pad and rub everything you've applied in the direction of the grain. Just takes a moment. While your doing this turn the instrument as you investigate the surface. You're looking for uglies. I have a magnifier glass on my work station that has a bright light. I use this light to bounce the rays off the finish showing me any imperfections. Reload and continue to make those tiny circles. You're actually pressing the oil down into the pores of the wood. Continue making these tiny circles until the instrument is completely covered. There should be no runs sags etc, if you've wiped it all down good with your finger. Remember the thinner the coat the nicer the finish. Takes awhile in the beginning but as you get more and more coats. It takes less time to apply and almost no time to dry.
Don't try to build up enough thickness to go through the grits after it's cured, go through the grits with your sanding between coats. This is dry sanding only, if you wet sand TruOil, you're asking for witness lines.
Every on 3 or 4 coats, let it dry 24 hours and sand out all the shiny spots, working your way through the grits from 600 to 1000. That is, 3 or 4 coats and sand with 600, 3 or 4 more coats and sand with 800, etc. If you sand through it's no problem, you're putting on more coats anyway.
Warm the oil for the final few coats, and get it on really thin and smooth. Let it cure for a month and you're done.
) et le model qui m'intéresse est vernis celle que j'ai la est mat. Donc ma question est, mieux vaut une guitare vernis ou mat, enfin cela à t'il une incidence sur le son? je me doute que le vernis protège l'instrument mais est ce la seule utilisation? 
![:]](./forum_guitare_fichiers/smilies/8.gif "Dan.San"){kind=small}
