|Project by splintergroup||posted 11-17-2015 06:43 PM||1750 views||13 times favorited||13 comments|
These were a bit more involved than I planned, but still fun.
White Oak, some quarter sawn, some rift sawn. Ammonia fumed finish covered with maybe 4 coats of “Tung Oil” wiping varnish, sanded smooth between coats. I quote the “Tung Oil” since this product has none in it, but I like it anyway. The shades are amber mica. The copper panels are FR4 copper clad printed circuit boards I etched with the Celtic “Tree Of Life”. The patina is sawdust soaked in a standard vinegar/salt mixture, then sprinkled over the boards for 18 hours.
I’ve made these before, just not with the enthusiasm I had after seeing Tom's creations
I never could get the lamp shade “just right” and working out the angles and cuts before making a simple prototype is very time consuming. These shade dimensions have a lot going for them. The overall angles and dimensions do a good job of centering with an off-the-shelf socket cluster. They also efficiently use a standard (30”x18”) sheet of mica, which can be pricey.
I made these lamps as prototypes so I could nail down the dimensions and cut procedure. Normally I don’t obsess over dimensions but the angles and alignments here are critical. The panels slide into 0.060” slots which must align exactly on four separate parts. Normally I think of cutting a single slot, then chopping off the individual parts. Can’t go wrong with consistency there right? Well the problem is crosscutting through the slot causes the splintery Oak to flake off inside the slots. I could avoid this by placing a temporary filler strip into the slot, or just cut the slots afterwards (I choose the latter).
QS White Oak is expensive. I make my own by using the edge of an 8/4 Oak slab that is plain sawn on its face (and by definition QS on its side) to complete the column. The shade and base pieces are done the same way with 4/4 stock.
All in all, 64 individual wood pieces are needed to create one lamp. That is a lot of sawing, sanding, and finish prep work. Things like the shade pieces each require routing a rabbet for the mica. That is a lot of small part routing which I did by hand, but I have a jig in mind for next time.
Cutting the angles:
The shade angles and half lap joints are easily cut (40 degrees) with my miter gauge and stop block. Consistency here is key. The bevel angle between the shade panels ends up being 23.05 degrees to get a tight miter. I set my saw to this angle with one of those digital tilt gauges. This is the first time I used one to set up a bevel on my saw, very handy and consistent, although I don’t know how much error there is between what the gauge claimed and what the angle really is. There is some wiggle room here. You can make a cut, check the fit, adapt and cut a thin sliver off again.
With the saw angle set, a jig makes cutting this awkward angle easy!
Upper End Details:
The upper cross shade supports, what Tom called “Corbels” were mortised into the column. Tom used screws to attach these in his version, which looking back was a smart move. Much simpler and much more likely to sit flush. Cutting the tenon on these parts (with a 2 degree slope) is fraught with traps. Reworking my order of operations between the router template to cut the shape and setup for the tenon is due for a review. Too much time wasted on setup for the tenon with these prototypes.
The lamp cluster uses a threaded shaft extending fully to the top of the shade where it can securely hold the shade in place. The ugliness is covered by a short section of copper tube (patinated of course).
Tom apparently has his shades just resting on the corbels. Overall this is very secure with the corbel notches, but knowing what it is like to live in a house with a cat made me think otherwise….
The threaded rod holds everything in compression. This allows me to avoid gluing the top piece of the base unit in place. I can easily swap out the copper parts if needed.
Copper Base Panels
These are becoming a “trademark” of things I make. Growing up as a kid, I was into electronics and made my own circuit boards. That knowledge came to use when thinking of what I could use to dress out the base. The process is left for another posting, but aside from buying the copper panels and photo resist paint, everything else requires common household products. My materials and process deviate a bit, but here is a good rundown on the process
When I get time to experiment, I’ll try the resist laminate films. Should be cheaper and easier.
The patina makes the copper work. Variations on copper patinas are endless, however I am “comfortable” with this version. It is consistent and responds well to being top coated (spray poly) to prevent flaking, etc.
I like fuming White Oak. I produces a nice color but best of all (for me) is the color penetrates the surface. I hate stains that rub away on sharp corners when I scuff between coats of finish. Fuming goes deep enough to avoid this. Dying penetrates well and has an infinite choice of colors, but tends to fade when exposed to sunlight.