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1  Stone Talk / Moderator, Hummingbirdstones ( Robin ) / Rough on the bench and slabs off the saw (general minerals board) / Re: Burned by baked carnelian? Bummer! on: April 06, 2016, 05:48:10 pm
All the Brazilian carnelian rough I have bought has probably been baked also. 90% will have the outer color rind (1/2in deep is common) orange and the inside will be gray. There is 10% though that has orange all the way through.

So heated this way by mother nature or man? Who knows for sure except the people mining it.
2  Lapidary Shop / Moderator, Catmandewe ( Tony ) / Cabbing And Grooving Machines.. Projects / New and Used Reviews / Re: Need info on the Graves Preformer on: April 06, 2016, 05:41:38 pm
I just received my Graves Preformer in todays mail.  After inspecting it, I am slightly disappointed in the motor assembly.  I purchased the motor since it was almost half the list price and if I would buy it later the shipping was almost $20.00.  I assembled the preformer and attached the motor.  After turning on the motor I found the motor shaft unscrews off of the dop shaft, an easy fix with a setscrew but I would have thought this should have been corrected way before this. Also the on/off switch is flaky, not a crisp switching. The spring clip used to hold the cam against the stop is too small to easily attach to the motor pin.  Also, if using the motor, you have to completely disassemble the unit to change cams.

The performer itself seems well made although it does not easily lend itself to being mounted on the left side of a verticle wheel.  The cam engagement is set up for operating on the right side and if you mount it on the left side you will not be able to adjust the pressure down into the wheel during the grinding process.

My recommendation, if you plan to purchase the performer, don't invest in the motor unit unless you plan to make the same shape cab in quantity.  If you plan to change the cams for different shape cabs, you are better off using the manual version.

Since the assembly is mounted on the right side of the wheel and your wheels rotate top down they use a motor with a clockwise rotation. The idea is to have the motor rotation running against the cutting wheel rotation. If the rotation is going WITH the wheel rotation then your cutting will be drastically slower.

The problem of course is when the threading on the shaft adapter is incorrect and allows the spindle to unscrew.
To fix this I use a set screw (like you mentioned) to prevent it from unscrewing.
3  Lapidary Shop / Moderator, Catmandewe ( Tony ) / Cabbing And Grooving Machines.. Projects / New and Used Reviews / Re: Need info on the Graves Preformer on: April 06, 2016, 05:20:05 pm
I start on an 80 grit hard wheel and then progress down to a 250 grit hard for final sizing. I'm sure it will take some adjusting to get the sizes down to an acceptable dimension.  Currently I am using Dop wax for the dops, but with a brass Dop, I expect to be using epoxy for the small cabs and was wondering if there is a good method of releasing the cabs from the Dops.  I plan to be using heat, either boiling or a torch first but would like to know of any reliable method as a plan "B".

http://www.finegemdesigns.com/doppingmethod-fgd.htm
4  Lapidary Shop / Moderator, Catmandewe ( Tony ) / Cabbing And Grooving Machines.. Projects / New and Used Reviews / Re: Need info on the Graves Preformer on: March 28, 2016, 01:54:39 am
It doesn't do domes just the perimeters.

If you can get it to work by hand then the motor should also work.

Are you cutting 4mm and 6mm rounds or are you cutting ovals? Also very small cabs are tricky since you will need very small dops. 4mm might be borderline small unless they are rounds. Rounds are the easiest to do.

Post a photo of your Genie machine. My unit works and I can clamp it to my Covington 4 wheel vertical machine.
There is a mounting bracket that comes with the preformer but there has to somewhere on the cabbing machine frame to clamp or attach to.

Note: This preformer will not cut symmetrical ovals when mounted to a HORIZONTAL lap. But this doesn't appear to apply to your situation.

Also there is a limit to how elongated a cab you can cut in some dimensions. Very long thin cabs might not work on this machine.
5  Stone Talk / Moderator, Hummingbirdstones ( Robin ) / Rough on the bench and slabs off the saw (general minerals board) / Re: Blue Jadeite deceptions on eBay on: March 24, 2016, 10:09:04 pm
Very common occurrence.
And of course they never altered the picture, so must be the light-source and or monitor. 
Happens on every platform including here on forums and FB? dont get me going. I'm fed up with looking at Fire Agate for exactly that reason.

By the way, must be something wrong with my eyes, but, except for your last shot showing light within the jade, I can't see any blue in any of the stones shown.

Trust me this piece is blue:

6  Stone Talk / Moderator, Hummingbirdstones ( Robin ) / Rough on the bench and slabs off the saw (general minerals board) / Blue Jadeite deceptions on eBay on: March 24, 2016, 11:17:36 am
Pretty much self explanatory. This problem is a plague on eBay and the internet.

https://www.youtube.com/watch?v=JSdb1XCwEIY





7  Stone Talk / Moderator, Hummingbirdstones ( Robin ) / Share Our Finished Cabochons and General Cabbing Questions / Tutorials / Re: Old stock Holley on: March 23, 2016, 04:41:53 pm
It's the same reason they call purple Namibian Chalcedony Namibian Blue Chalcedony.

Maybe since there are far fewer actual blue gems than purple gems suppliers believe they can make more sales by calling their purple gems blue.

Note: Also most (if not all) of the Mt. Airy Blue Chalcedony is also really purple.

8  The Gathering / Our Place / Re: Why are images here not working recently?? on: February 21, 2016, 03:58:59 pm
Get a cheap hosting package at nearlyfreespeech.net and then post your images from there using img tags.
9  The Gathering / Our Place / Re: Light Tents/Light Boxes - Anyone Use One? on: February 21, 2016, 03:56:06 pm
I tried it and didn't like the results. Not using these systems allows reflections which shows off the high polish on my gems. Diffused light gives results that are rather blah IMO.
10  The Gathering / Our Place / Re: Recommendation for a Camera on: February 19, 2016, 11:59:26 pm
Canon PowerShot G3 4.0 MP. I bought a replacement for mine on eBay (used) for about $75.

Simple easy to use and takes good photos of gems and jewelry. I use a tripod and SoLux lighting with mine.
11  Stone Talk / Moderator, Hummingbirdstones ( Robin ) / Share Our Finished Cabochons and General Cabbing Questions / Tutorials / Re: Kingman Black Matrix cabs on: February 15, 2016, 02:17:55 pm
I really like good stabilized kingman. Here is a beauty I just bought on eBay:

http://www.ebay.com/itm/WRG-High-Quality-TURQUOISE-Rough-Kingman-Arizona-Mine-Stabilized-2-8-Ounce-/401067335819?_trksid=p2047675.l2557&ssPageName=STRK%3AMEBIDX%3AIT&nma=true&si=OQEuH4484uqXKa9MGgHY0sRbSik%253D&orig_cvip=true&rt=nc





Kingman Red Matrix turquoise.
12  Stone Talk / Moderator, Hummingbirdstones ( Robin ) / Rough on the bench and slabs off the saw (general minerals board) / Warning new purple "jade" from Bolivia on: February 15, 2016, 11:52:11 am
This appeared on eBay and I bought a piece.

Cuts like butter in my trim saw so I checked hardness.
It is scratched easily by lapis. And it won't scratch lapis.
Therefore hardness estimated at 4-5 MOHs max.
Specific gravity was 2.93.

eBay seller claimed the rock was sold to them as jade.

Then I got an email from the supplier of the eBay seller. Their claim:
"it is a combination of nephite, lizardite and fluorite."

So they believe it is OK for them to call it jade.



13  Lapidary Shop / Moderator, Catmandewe ( Tony ) / Miscellaneous Shop Talk / Re: Anyone have a handle on cutting Lapis? on: February 12, 2016, 07:33:20 pm
Surprisingly I have found Poly-Al F to be almost universal for many stones.

Two links to check out:

http://www.hayneedle.com/product/polyalfpolish.cfm

http://www.diamondpacific.net/polish.html

Note: If you ever see any old cream colored Raytech 100% cerium oxide buy it or message me. This was the best cerium I've ever worked with.

14  Lapidary Shop / Moderator, Catmandewe ( Tony ) / Miscellaneous Shop Talk / Re: Anyone have a handle on cutting Lapis? on: February 12, 2016, 01:00:18 pm
Don't use Cerium Oxide for lapis.

Thank you....Why is that?

Because it doesn't work as well.
15  Stone Talk / Moderator, Hummingbirdstones ( Robin ) / Share Our Finished Cabochons and General Cabbing Questions / Tutorials / Re: Kingman Black Matrix cabs on: February 11, 2016, 03:59:47 pm
I doubt it's quartz actually but maybe someone else here knows what the white matrix is composed of.
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