Inline pics to be added later.
I have been printing on a ceramic floor tile with decent results as long as it was warmed first (heat gun). As I didn't want to destroy my only working printbed, I looked around for something similar locally. Nothing was available for polished, flat tiles. There was a special name for the tile I had... basically it means it was polished until 'optically' flat. Reflections are not distorted... really, actually, flat. Refractory? Something like that.
Instead, I found the stone tiles. They were also polished (ground really) flat and were ~1/2in thick. They didn't say 'refractory' or whatever like my tile (which I could have ordered, but had to get a box of), but the reflections from it were not distorted. Good enough. They were also dirt cheap on clearance, and I could screw up 3 times.
For the ceramic tile, I was going to glue 1/4in nuts to the back, wind on those, and then encase the windings in cement. The extra thickness I now had gave me the idea of cutting grooves in the back to make my windings embedded. The back of my tile could be flat then, this should increase heat transfer, and I thought that heating the tile from the 'middle' may help eliminate any tendency to warp.
I wonder if I can cut these? Stone is hard, requires special blades, you need water cooling right? Nope. It was easy.
I had a masonry blade I bought a while back for my circular saw. The arbor also happened to fit my table saw. On it went.
Figured out a pattern which would give me a gap in the middle and a little wider edges. It was start at 1in, then 3/4 apart all the way across, and ending with 1in. I gingerly started to make the first cut, at 1/2 my intended depth. The dust was overwhelming at a few inches in, but it actually cut easier than hardwood plywood minus the blade not tracking at all. I started to get excited that this might actually work, then stopped everything and 'suited up' to be blasted with dust for hours. Respirator, goggles, hoodie tied shut, and gloves held on with rubber bands were donned. I've heard of people getting seriously ill, long term, from stone dust. Silicosis I believe it's called.
Cut the first few grooves at half depth. Was worried about heat buildup causing the stone to crack. Then I got impatient and switched to full depth on the first pass (half way through the tile). I figured, hey... I got 3 more tries if it explodes. It didn't. It cut like butter.
The tile I was using hung off the edges of my base and looked funky. Since this stuff was cutting so nicely I decided to see if I could get a circle out of it. Drew a circle on the back with a pencil, and free-handed some relief cuts close to the line. Then I got a little cocky and tried to free-hand the circle itself. It worked pretty well. The edge of the blade is a good grinder so you don't have to be perfect the first time... just stay on the right side of your line. :)
I needed a groove around the edge to allow my traces to turn around inside the tile. It was cutting so nicely, I decided to just try to free-hand that as well. Turns out free-handing a cut isn't so easy when you can't see the blade. It also tended to 'grab' when I missed the previous cut. The cut I ended up with wasn't useable for winding as it had sloped edges.
I started over.
Did all the straight cuts again, and this time I pre-drilled a hole almost through the tile right in the center for popping in my thermistor later on, and cut the extra slot to run the thermistor wire almost to the hole. Took a bit of plywood, put a pin in it, and clamped it to the saw with the pin located directly across from the top of my blade. Cutting a curve with a straight blade will probably be difficult. This time I took my time. Started with the blade down, turned the saw on, and raised it until it contacted. Rotated the tile. Raised the blade, rotated the tile... repeat this about 15 times and I was through. Not so hard..
Moved the jig over a half inch, and cut the edge groove I needed half way through....Read more »