Arron
8th November 2013, 10:09 AM
I'm trying to solve a long-standing problem that I've had with marquetry. If you look at the attached image you can see what I'm doing. I've dyed the red and green veneers myself as I cant buy dyed veneer locally and am unwilling to buy overseas due to postal charges. The dye doesn't go all the way through, but I've come to accept that as the best I can do under the circumstances. It causes a problem when I go to sand the face of a veneer, which I have to do to flatten and remove any glue or rubbish on the face. A very light sanding actually improves the look of the dyed veneer - gives it a kind of faded antique look. However sand too much and the pale timber starts to show through - as you can see with the lowermost leaf. The problem that arises is when I need to sand aggressively to remove congealed glue on the surface. I hate sanding veneers hard at any time, but its especially bad when I find myself sanding through the dyed surface layer and exposing the poorly coloured stuff underneath.
So why do I have to sand it hard - because I'm using PVA glue in a press, and the glue is forced up between the joins in the marquetry and spreads out across the surface.
I use quite a thick layer of glue - why? well too much glue is insurance against the opposite happening (a thin layer might leave some spots a bit dry, with subsequent failure). I could use less glue, but I've refined the method over a number of years and I don't want to change things and risk bond failure.
I also don't want to change glues. I could use hide glue, but although it solves problems it brings more of its own (too bigger issue to go into here).
I wont use contact glue.
I also don't want to use a scraper to remove the congealed glue from the surface - I'm never confident using a scraper across marquetry. Also, I have injuries to my hands that mean I'm not really able to use one - not aggressively anyway.
I have to admit one thing I haven't tried is coating the surface of the marquetry with shellac before glueing it up. Maybe this would seal the veneer and stop the glue setting on it, and after pressing the glue would be easily scraped off and then the shellac sanded off? I haven't tried it because each trial is time consuming and I'm over purchasing and trying things that don't work in this instance, so maybe someone else who's tried it or something similar can advise and save me some time.
I should also point out that the face is covered with contact paper before being put in the press. This is to prevent stuff (typically iron scrapings from the mechanism of the press) getting onto the face of the veneer. I don't think this is relevant, but maybe it is.
I have also read that overseas one can buy PVA glues which are specially made for this problem. They are thickened with something so they don't bleed through. They can be bought from veneer suppliers in the US but I assume they cant be posted. I have considered mixing my own but its pretty daunting - I don't want to make something which seems to work but fails some way down the track.
So I guess the ideal solution would be :
1. a way to prevent the glue squeezing through the gaps in the marquetry (aside from smaller gaps).
2. or a way to prevent the glue that is squeezed out between the gaps in the marquetry from bonding to the surface.
3. or a way to painlessly remove the congealed glue before giving the whole thing the very lightest sanding possible.
cheers
Arron
292566
So why do I have to sand it hard - because I'm using PVA glue in a press, and the glue is forced up between the joins in the marquetry and spreads out across the surface.
I use quite a thick layer of glue - why? well too much glue is insurance against the opposite happening (a thin layer might leave some spots a bit dry, with subsequent failure). I could use less glue, but I've refined the method over a number of years and I don't want to change things and risk bond failure.
I also don't want to change glues. I could use hide glue, but although it solves problems it brings more of its own (too bigger issue to go into here).
I wont use contact glue.
I also don't want to use a scraper to remove the congealed glue from the surface - I'm never confident using a scraper across marquetry. Also, I have injuries to my hands that mean I'm not really able to use one - not aggressively anyway.
I have to admit one thing I haven't tried is coating the surface of the marquetry with shellac before glueing it up. Maybe this would seal the veneer and stop the glue setting on it, and after pressing the glue would be easily scraped off and then the shellac sanded off? I haven't tried it because each trial is time consuming and I'm over purchasing and trying things that don't work in this instance, so maybe someone else who's tried it or something similar can advise and save me some time.
I should also point out that the face is covered with contact paper before being put in the press. This is to prevent stuff (typically iron scrapings from the mechanism of the press) getting onto the face of the veneer. I don't think this is relevant, but maybe it is.
I have also read that overseas one can buy PVA glues which are specially made for this problem. They are thickened with something so they don't bleed through. They can be bought from veneer suppliers in the US but I assume they cant be posted. I have considered mixing my own but its pretty daunting - I don't want to make something which seems to work but fails some way down the track.
So I guess the ideal solution would be :
1. a way to prevent the glue squeezing through the gaps in the marquetry (aside from smaller gaps).
2. or a way to prevent the glue that is squeezed out between the gaps in the marquetry from bonding to the surface.
3. or a way to painlessly remove the congealed glue before giving the whole thing the very lightest sanding possible.
cheers
Arron
292566