Tuesday, August 26, 2014

Sometimes the camera rests

About a month ago my brother was commenting on this blog and, talking about some of the projects I've posted here, he wondered at my ability to stop along the way and take photos.

Well I don't always remember, and this is a case in point.

Quite some time ago I carved a couple of pieces that I wasn't entirely happy with. Actually that happens quite often, me not being happy with something I've done, but this time I eventually went back to the pieces, and reworked them. Stripping the finish and doing quite a bit of additional carving to eliminate some of the chunkiness and reshape them for better flow.

This is a photo of one of the pieces as it came out the first time I did it.

And here's the same piece after re-carving and the addition of some tinted epoxy in the larger defects to create a little sparkle.

I wouldn't go quite so far as to say I'm ecstatic, but I do feel better about them; for now anyway.

Unfortunately I can't seem to find a 'before' photo of the other piece but I had the same issue with it's original 'form' as well.

But through the process of making them 'better' I didn't think to pick up the camera until I was just about finished,

As in getting ready to apply the finish.

Since adding epoxy to a curved surface such as this means that some sanding is going to be necessary to get the two surfaces, wood and epoxy, to blend, the original nice shiny finish on the cured epoxy is lost. And I know from experience that no amount of sanding and polishing will restore that shine without damaging the surrounding wood.

So the fix for that is to take a fine brush and coat the epoxy with some sort of gloss clear-coat or varnish. Here I've coated the right side of one of the larger patches and the left is still the raw surface sanded to 600 grit. The trick is to use the brush sparingly, to flow the finish on but then just leave it alone. Otherwise you're going to leave surface irregularities, brush-marks, and the more you mess with them the worse they get.

Here's a bit of almost useless trivia. The difference between a gloss finish and semi-gloss, egg-shell, or flat finish is the addition of increasing amounts of little bits of clear minerals, (With pigmented finishes these bits might be neutral instead of clear.) and by little I mean little.

As the finish cures the resins shrink, and as they do some of the little mineral bits get left on the surface, like tiny rocks right at the edge of the water. These rocks are a couple of ten-thousands of an inch in size which is too small to see but larger than the wavelength of light, so they scatter it, the light, and break up the 'gloss' of a purely reflective surface.. The more rocks the more the light is scattered.

A couple paragraphs ago I started with 'almost useless'. Ever notice that a can of gloss varnish will not have anything about stirring before use in the instructions, (Never shaking!! That just introduces bubbles and bubbles are our enemy!) but the can of semi-gloss will?  So if you happen to have a can of semi-gloss that's been sitting on the shelf for a while, (Weeks at least.) and you pick it up very carefully and handle it gently as you open it, the resin sitting on the surface will have few if any of those little rocks in it because they've all sunk toward the bottom. By carefully dipping finish only from the surface the resins will actually cure as a gloss finish.

This is what we locally call Red-Heart Cedar, which is actually a Juniper. But it doesn't matter what you call it, it's a soft wood with a very absorbent grain. To put a glossy varnish finish on it requires coats and coats and coats of finish, as it keeps sinking into the wood. For these two pieces, which I have frankly already put far too much time into, I opted for the natural finish of several heavy coats of mineral oil.

It's really sloppy work slopping the oil on thickly with a rag, so you want to make sure there aren't any other pieces laying nearby that could get splashed because once the mineral oil get on something no other finish will stick. After a few hours the oil will have soaked in, but eventually you get enough into the grain to get rid of that dry look. Then a little buffing with a clean rag and you're done. Relatively quick and easy.

Another couple advantages of mineral oil is that it is food grade so if someone uses one of these for candy or nuts there's no problem, and the finish can be rejuvenated, faster than you can clean the kitchen counter after making chocolate-chip cookies from scratch, with a quick swipe of additional mineral oil once in a while.

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