Author Topic: Motorized turntable for grinding  (Read 47 times)


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Re: Motorized turntable for grinding
« Reply #15 on: February 09, 2018, 04:53:28 AM »
Don't leave the mirror on the tool over night. Yep, when it dries out, it gets stuck. Same thing when you polish. If you're not going to polish, keep the mirror off the pitch. It too will get stuck.Youwill becold pressing before you start to polish, anyway. Leaving the mirror on the lap will make the lap thinner and thinner and you'll have to keep opening up the facets.

Ohh, now i get it. Think Gary is on to something here
I have done this also, that is leave the mirror on top of the tool overnight. Next day they were fused.
I fix this by putting tool/mirror in a tray and fill it with water so it covers both. Then leave it overnight.
Next day they normally can be slided from each other.

Ok, just want to point out one thing about the temperature, Augustus.
For the rough work, hogging out, coarse grinding, fine grinding the temperature just have to be comfortable for you.
For polishing out, not too hot, keep it in the range that your pitch is spec'ed for.

But for figuring, IMO, you _must_ keep the temperature quite even from session to session. Keep the flux down to a few degrees.
And of course still within the temp. range the pitch is spec'ed for.
The reason is that the pitch will work differently at different temperatures. So at one session you might understand how the pitch works the glass.
The next session at a different temperature the pitch works in another way even when you do the same strokes!
This kinda thing, where things go in the right direction figuring-wise and the next it all goes to s****, it can really make you go crazy.

I've been there!
It got me so frustrated that i almost gave up. I was working in my apartment in the summer and the temp goes up'n'down alot. Hot days, cold days and so on...
In the end I put the project on at shelve and left it there for more than a year.
Advice from this forum and other glass-pushers in my country pushed me in the right direction, and suddenly it dawned on me.

CN is awesome, there really some giants in here, really really good and knowledgeable glass-pusher here with decades and decades of combined experience!
Keep asking, listen and learn

But for now, forget about the figuring. Deal with it when the time comes.


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Re: Motorized turntable for grinding
« Reply #16 on: February 09, 2018, 11:25:31 AM »
Lars, lots of good comments. I agree with every thing you said.