Low RPM motor solution... finally!

[laserist]

I forgot to mention that I turned the glass over after cutting 1/2 way through on the outside diameter to avoid the shattered edge that happens when the hole saw punches through the glass...

[buffo]

I forgot to mention that I turned the glass over after cutting 1/2 way through on the outside diameter to avoid the shattered edge that happens when the hole saw punches through the glass...

Excellent advice!

I haven't tried cutting glass with a hole-saw, but I have cut some very thick glass mirror stock using a dremel tool and the brown oxide cutting wheels in the past, and in that case I also worked the cut from both sides. It was incredibly slow going though. Those oxide wheels will heat the glass up to glowing temperatures very quickly, at which point it will crack and the crack will run off in a random direction. So you cut a scratch, then wait, then cut a little deeper, then wait... Then flip to the other side and cut a little bit, then more waiting. Ugh.

I suppose if you had a water-cooled saw it might allow you to speed things up a good bit though. (Again, I've never tried this myself...)

Adam

[laserist]

When cutting with the hole saws I did use water cooling. I wouldn't try it with a Dremel - you'd have glass dust thrown everywhere. (Of course dry glass dust is a whole nother problem!) If I do it again I'll make a leak proof aluminum "pool" fixture to hold to glass on one side by its edges, and with a 3/8 inch stud to clamp the glass on the other side via the hole. My setup last time leaked... Not that big a deal, but annoying. I used some anti slip thick shelf liner under the glass to avoid too much stress.
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[absolom7691]

My setup is as rudimentary as it gets but I was able to get decent results. I also used water cooling, just the hose on a trickle. I cu the glass on a piece of 1/4" plywood. As the wood got wet, the glass was held in place pretty firmly. I just let the hose trickle over the glass and saw. I cut my discs with a cordless drill, so I had to use an acrylic guide to keep the holesaw centered until I had a viable cut groove. I just let the weight of the drill do the work. This is probably all the wrong way to cut these, but I was able to cut 8 discs with no breakage and just a little bit of edge cleanup.

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[absolom7691]

I etched and built a new board for the new drivers. Now that my optical deck will be much smaller, I am redesigning my lumia projector. Will this build ever be finished?? lol

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[absolom7691]

Roger, I cut and etched your board today. I'll do my best to get it in the mailbox tomorrow.

Some pics of my process:
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