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--- projects:crokinole_board:work_logs:work_log_2 [2019/07/03 12:05] – created tjhowse
+++ projects:crokinole_board:work_logs:work_log_2 [2022/01/23 00:22] (current) – tjhowse
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 ====== What I want to accomplish ======
-  * Do some test cuts of some scrap plywood with the router.
+  * Do some test cuts of some scrap plywood with the router,
+  * Build a circle-cutting jig,
+  * See how plywood sands,
+  * Test out the stain,
+  * Test out the varnish.
 ====== What I've done ======
-I want to experiment with a few different factors:
+=== Circle-cutting jig ===
-  * Direction of cut,
+{{:projects:crokinole_board:work_logs:pasted:20190705-124801.png}}
-  * Depth of cut,
-  * Speed of cut,
+I inherited this router from my father in law. It took a moderate amount of WD40 and violence but I got all the moving parts moving. It's quite powerful, and takes 1/2" bits. Some of the attachments are missing but I bodged together the above quickly. There is very little flex or wobble in this system, so it should cut good circles.
-  * Bit choice,
-  * Blowing sawdust away.
+=== Test cuts ===
+I got some old scrap bits of plywood and rounded off one of the ends. I tried a few shallow cuts with a 8mm straight router bit and it was effortlessly cutting through without slowing down or leaving much of a burr. I haven't concluded whether it's better to move in one direction or the other. I imagine as long as the RPM remains high there isn't much of a difference.
+{{:projects:crokinole_board:work_logs:pasted:20190705-125521.png}}
+I did have some blow-out at the start and ends of the cut where one of the internal layers was spat out the side. I won't have this when cutting a circle, because there are no ends. The cut also exposed some internal voids in the ply: knots laminated on both sides. I'm not sure what I'll do if I encounter those when cutting the proper board. If there's only a few I can fill them with sawdust and PVA. If there's lots I might have to go up to marine grade ply to get the finish I want.
+{{:projects:crokinole_board:work_logs:pasted:20190705-125530.png}}
+I ran a great many cuts in different directions with different feedrates.
+{{:projects:crokinole_board:work_logs:pasted:20190707-031415.png}}
+My conclusion is that the direction doesn't matter all that much. Variability in the texture of the ply makes a bigger difference. This said, I generally got the best results moving at about 10-20mm/sec with a 6mm straight bit cutting all the way through 12mm ply, turning counter-clockwise with a clockwise-spinning bit.
+=== Stain test ===
+{{:projects:crokinole_board:work_logs:pasted:20190705-125556.png}}
+I also sanded and stained a scrap piece of ply. I started with 80-grit and ended up with 320 grit, sanding by hand with a sanding block. The surface was smooth but lumpy on a larger scale. I think I need to spend longer with the coarser sandpaper to even out the bumps. I'll be sanding the actual board with an orbital sander, so it won't be so tiring.
+{{:projects:crokinole_board:work_logs:pasted:20190705-125756.png}}
+I dusted the wood off and put a moderately thick coat of stain on and wiped most of it off with a chux after a minute or two. There are some deep scratches from the coarser grades of sandpaper. I think I just need to spend longer sanding with the finer grades to remove these.
 ====== What I want to accomplish next time ======
-  * Build a circle-cutting jig for the router.
+  * Go through a few varnish -> sand -> varnish cycles and see how this scrap piece improves,
+  * Build a wood steamer and bend the edge strips.
+[<6>]