Tips for new facetors

[Badge]

Thanks for the advice Pat. I'm using 3000 pre polish and then 100k polish atm. Is 100k too much? I do have some 14k I can use instead. And that stone has a pavillion of 42.5 degrees approx. because the SRB design for the 64 index had 42.1 degrees. The protractor on my machine is probably way off because trying to get 45 degrees for the table is closer to 46 than 45.
I'll try to find the pic from Jeff Graham.
The material I'm using is sub standard. Full of tiny flaws and black streaks and doesn't polish as well as the 2 sapphires I have cut so far but it is as you say good for practise.
The one below is better than the SRB above but you still need to get the right angle to get any glimps of a sparkle. And I spent hours polishing it.
Long way to go yet, but I'm enjoying the time spent learning.
Cheers.
Badge.

 

[Badge]

I found the pic and the article from Jeff Graham Pat. He was using the red boulle where I am using the blue rough cut sticks but had the same pitting.
This one I did with a similar if not same red material as he used and as you can see I'm a long long way behind.
But he makes some comments that made heaps of sense regarding synthetic sapphire. Learning the art of polishing appears to be the hardest part of faceting. But Dihusky did warn me. He was right as usual.
Cheers.
Badge.

 

[Pat Hogen]

The secret to corundum, of any persuasion, is 3k > 8k > 100k but do not use too much of the 100k on your lap, smear it and clean it and watch your results. You can go up and down with 100k, as in too much and not enough, so keep your eyes pinned to what is happening. 4 drops of sewing machine oil around the lap, drop a little 3k powder into each drop of oil, smear around in circles with your finger, use a cosmetic pad just to wipe the lap, and use little pressure. Then move on to 8k and finally 100k using the same procedure. At the 100k point you can just rub your stone across the non-moving lap and have a look at your result, that should tell you how to proceed with more or less powder. You may be using diamond lube sticks but the process is the same. Time is your friend!

 

[Badge]

Natural sapphire seems so much easier to cut and polish.
Still not easy but I'm getting the hang of things more now. The remarks from both Pat Hagen and Dihusky about less being more when polishing is well and truly accepted now. And keeping everything clean seems to be helping more too. This small 1.1 carat sapphire (it started as 2 carats) which I lost off the dop doing the 19.8 degree cuts and replaced on the dop somehow turned out OK. A fairly good polish imo.

I've just received a couple of pieces of topaz in the mail and I'm sure Dihusky is the man who knows his way around topaz but if anyone else has any tips I'd be happy to take them. There seems to be a few layers on each piece. I take it the table facet should be horizontal to these layers? I'm not jumping into them just yet, because I'm sure topaz will have it's own difficulties that need to be researched.

The 1.1 carat stone.

 

[Dughug]

"There seems to be a few layers on each piece. I take it the table facet should be horizontal to these layers? I'm not jumping into them just yet, because I'm sure topaz will have it's own difficulties that need to be researched."

Badge it sounds like you are describing the cleavage plane. I would recommend that you offset the table facet to be 5 degrees off the cleavage plane. If you align the table facet to the cleavage plane which like the pages in a book will peel off if you cut and polish on the same plane.

The best experience you can get with topaz, or any other stone for that matter, is just do it and learn what works for you.

 

[Badge]

Thanks Dughug, I've spent some time looking into faceting topaz and the first thing that came up was to offset as you described. Suggested offsets were anything from 5 to 15 degrees, so I went the average and just finished dopping my first piece at 10 degrees (or as close as I could to 10 degrees). I have two pieces so if I'm off too far I'll try 5 degrees for the next one.
I didn't even know those layers were called cleavages so I've learned something already.
Cheers.
Badge.

 

[Badge]

Well I think I like topaz for cutting and polishing. So far.
My first attempt below on a very thin stone and I was worried I wouldn't have enough stone left for the crown but snuck in.
The photography still isn't as good as needed but there aren't too many flaws to find.
I think .

More time spent next time on the pavillion I think. Not happy with it because it looks clearer/more transparent than I think it should. The original stone was very clear anyway but I think it needs more sparkle.

Baby steps.

Cheers.
Badge.

 

[Pat Hogen]

Well that is a good go Badge, congratulations. You may want to consider a design like Sunburst, Portuguese or Scintillator, because of the extra angles in the pavilion it will brighten up and remove that empty space through the crown. Closing the crown angles with a smaller table will assist, as well. Good stuff!

 

[Badge]

Thanks for the advice Pat Hogen.
I was trying for a smaller table but ran out of stone.
I did read quite a bit about cutting topaz and what I read was fairly confusing. The critical angle is 37°?
Most designs have pavillion and crown angles more acute ( or is it obtuse? ) than 37°, ie 42° 52° etc.
If the stone is wide and I use those angles there is no way I can fit that design. So I'll look at the Sunburst, Portugese and Scintillator designs to see if I can fit the other piece in.
I only have the 64 index atm otherwise I'd try the Princess cut. That's one for down the road.
Thanks again.

Cheers.
Badge.

 

[Badge]

I started this topaz before taking the faceting machine into Matt Young for a total "FIX".
Pat Hogen I know you have seen it.
An astounding difference to just about everything I have been doing. No more grating the teeth over why the facet doesn't line up to polish is just great. Matt does such a good job and so quick with returning the machine.
Since returning from my trip to The Gemfields the only use it has had was to finish this stone. In the coming weeks I think I'll be trying it out a lot more.

Cheers.
Badge.

 

[Badge]

My other partly finished project now all done ( a corundum boulle chunk I did earlier that was just too rough). Tomorrow I can begin with some of the rougher sapphires from Rubyvale/Sapphire. I don't trust my faceting to do the good ones so they are going to be cut elsewhere, I suppose Lamberts in Thailand. Unless someone has a better idea like a local. The zircons as well with one of them probably large enough for me to cut but isn't inclusion free.
I was told to ask for the better quality stones to be cut to Australian standards, I suppose that means to the correct design and not just cover the pavillion with facets? If so I'll be asking for that with a few for sure.
I'm really starting to enjoy this faceting. But not to the point I'd risk good stones until I'm more confident.


Cheers.
Badge.