Hi Everyone ... I’m back at it again with my latest Marquetry project … ready to blog a small section for you to chew upon! This is where I left off, leaving you all in suspense ….
..... because now I’m going to delve into the mysterious, but not very complicated wonders of sand-shading!
This is my set-up for sand-shading. There’s a hotplate, which I block up for some air space between that and the board everything sits upon. The round cake pan holds silica sand ... and silica sand is easily obtainable at pet stores! That is the granular stuff that is liberally sprinkled on the floors of bird cages … and just may come in a box label ‘Bird Gravel’. It is NOT in powdered form, and please avoid powered silica (used in the making of glass) as the dust from that could lodge in your lungs and cause you future grief!!!
My layer of sand in the cake pan is approximately 1” thick … set to medium high heat and left there throughout its use. When I’m finished sand-shading I just pull the plug on my hotplate. Once you start playing around, you’ll find out what temperature works best for you. When that happens, you too will want to leave that ‘perfect’ setting alone! My hotplate comes with an on/off switch which remains left in the ‘on’ position. I don’t know how many times I used to fret far from home base, wondering if I turned that darned thing off before leaving. Of course I always turned it off … but far better now, I make a conscious effort to watch myself pull that plug … it’s harder than merely flicking a switch. I’d rather tell myself loud and clear to pull the plug … do it … and then stop worring about burning down my workshop!! But now (of course) I worry in wonderment over actually having pulled that plug!! It’s an age thing I think … my mind wanders and skitters off in all directions! Ah … back to sand-shading …... where was I? Oh yes … I also have a cake rack set between the burner and pan. Believe it or not, if used constantly … the bottom of that pan will eventually burn out! The cake rack seems to have solved that little issue.
Unless you feel the urge to continually burn your finger tips by using a small pair of tweezers to hold the veneer piece over this hot sand … I strongly suggest investing in long handled pinchers (dear old Dad-the-Locksmith gave me this one you see in the picture!) and a long handled spoon.
Now, with the silica sand well heated, we’re ready to do some sand-shading!
It’s as simple as that!! You decide just where you want to scorch the veneer … because basically that’s what you are doing. The controlled burn has to be just enough to go through the veneer so its effect won’t be removed later on during the process of scraping and sanding your completed work smooth before applying a finish.
There are several motions used to sand-shade veneer: In this picture I’m just scorching the edge. In doing that, I just hold the veneer against the bottom of the pan and move it along the edge where desired.
If you want to scorch beyond the edge ….. you just fan the veneer back and forth through the hot sand until you arrive to the desired effect. Be careful though … it doesn’t take long!
If you want just a mild shading in a central location ….. you scoop the hot sand onto the spoon and in a series of fairly quick motion … pour the sand from the spoon onto that area, and just a quickly and smoothly … tilt the veneer until the sand falls back into the pan. Repeat that process until you’re satisfied with what you see.
If trying to scorch an inside curve ….. you can either scoop the sand onto the spoon and run the inside edge over that pile … or scoop the sand into a pile in the pan to do the same thing.
And of course you are going to practice first … right?!!
I prefer to work the design and sand-shade at the same time because along with sand-shading, comes shrinkage. Intense heat has that effect on veneers! Going back to the first photo in this blog, you’ll notice I’ve patched the background Rosewood together with the template for the decorative motif.
I quickly came to the conclusion that my finger power isn’t what it used to be!, and hand-cutting through my cardboard template isn’t as much fun anymore … so I’ve used the scroll saw, then taped the multiple pieces of the motif back together again … placing that into the background. Why? ... because at various points throughout the process of working the motif, the edges will butt up against the background edges (wood meets wood), and there is where you want to cut most exactly for a good fit.
Notice the gap between the Poplar veneer used for the motif, and the cardboard template? … now imagine waiting until you’ve cut out the entire motif, then tackled the sand-shading. You would have lots of gaps to deal with! Some veneers shrink much more than others … Poplar seems to be one of those shrinking violets!!
There … now you can actually see something! Remember there are 4 sides to this box! The rest of the decorative motif pieces have been sand-shaded at the same time, and will be eventually pieced together … and placed into the other 3 panels.
I’m going to leave you stewing as there are pressing matters to attend. But when I return, you’ll see more sand-shading and the window approach to working this design. Thanks for peeking in and checking up on me!! All questions and comment are indeed welcome :)
Until next time, I’m sure there will be a moment to ponder the technique of sand-shading over a lovely glass of Merlot!!!
-- Elaine in Duncan