dshanpnw
fully equipped rock polisher
Member since December 2020
Posts: 1,149
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Post by dshanpnw on Dec 12, 2021 10:02:53 GMT -5
Hello everyone, I think the best way to ask this question is to state my purpose. I want to face polish sppecimens such as, Owyhee and Biggs jaspers, several types of agates, Laguna, Coyamito, and Brazilian, all for display. And, I would like to start cabbing. Would a cabbing machine such as the Kingsley North Cabber 6" or 8" do both? What is a belt sander best used for, such as the Covington 4 station expanding drum unit? I know a flat lap would probably work very well for the face polishing of specimens. So the real question then is this, could I use a belt sander for both face polishing specimens and cabbing, or would a cab machine be best for both purposes? Thanks for any help and advice.
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Post by Rockoonz on Dec 12, 2021 10:44:58 GMT -5
When I was introduced to cabbing in the 70's in a jewelry shop in my high school, they had 2 double belt sanders for cabbing. I think they were Nelson machines custom made for schools. I have one of the longer Covington machines that I set up right before we moved, hasn't been run other than test run before I crated it, and it's waiting for me to finish our kitchen upgrade so the cabinets and counter will add to the wet bench space.Having the flat platen behind part of the belt for flats, and the unbacked of the belt to flex for domes worked as far as I remember. Changing belts and re-centering them is more time consuming than expandos though, and multiple expandos with minimal belt changes would be best if you want to do one at a time.
If your specimen slabs are a lot wider than the wheels on anything there will be issues doing flats on a cabber if the wheels are so close together that you can't avoid hitting 2 of them, for relatively large slabs a wet angle grinder with a set of polishing discs for stone countertops and a table surface the slabs will stick to is also a possibility instead of a cabber, and prices can be reasonable enough to possibly get that and a cabber. I have been promised a contour grinding and polishing class from a new friend who I am doing saw repair for, so the grinders that have been gathering dust may be going to work soon.
I like flat laps but really only use them for specialized jobs, and a cabber with a 1/4"-20 threaded hole at one end of the shaft can easily mount a disc for quick and small flat jobs as well, in a limited space or money situation.
Your available space and funds are a big factor, moving heavy gear around is a literal drag.
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dshanpnw
fully equipped rock polisher
Member since December 2020
Posts: 1,149
|
Post by dshanpnw on Dec 12, 2021 12:02:49 GMT -5
When I was introduced to cabbing in the 70's in a jewelry shop in my high school, they had 2 double belt sanders for cabbing. I think they were Nelson machines custom made for schools. I have one of the longer Covington machines that I set up right before we moved, hasn't been run other than test run before I crated it, and it's waiting for me to finish our kitchen upgrade so the cabinets and counter will add to the wet bench space.Having the flat platen behind part of the belt for flats, and the unbacked of the belt to flex for domes worked as far as I remember. Changing belts and re-centering them is more time consuming than expandos though, and multiple expandos with minimal belt changes would be best if you want to do one at a time. If your specimen slabs are a lot wider than the wheels on anything there will be issues doing flats on a cabber if the wheels are so close together that you can't avoid hitting 2 of them, for relatively large slabs a wet angle grinder with a set of polishing discs for stone countertops and a table surface the slabs will stick to is also a possibility instead of a cabber, and prices can be reasonable enough to possibly get that and a cabber. I have been promised a contour grinding and polishing class from a new friend who I am doing saw repair for, so the grinders that have been gathering dust may be going to work soon. I like flat laps but really only use them for specialized jobs, and a cabber with a 1/4"-20 threaded hole at one end of the shaft can easily mount a disc for quick and small flat jobs as well, in a limited space or money situation. Your available space and funds are a big factor, moving heavy gear around is a literal drag. Hello Rockoonz and thanks so much for the reply, it's very helpful. Start from ameteur and work my way to professional, Superb! I was just going to edit and rephrase my question to be, what is the best method to face polish flat surface specimens such as Owyhee and Biggs jaspers, a belt sander or cabber? You definitely answered the question about polishing larger surfaces on a cabber; hard to maneuver them on tightly spaced wheels. I'm not going into a professional business or selling, just a personal collection, but I want them to be as perfect as possible. I'll bet I can sand the larger agates on the disc at the end of a cabber shaft fairly well. So, I think I have made a reasonable decision to go with the cabber and an angle grinder if necessary. If the specimens start becoming seriously spectacular then I will think about a belt sander. Thanks so much. |
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Post by perkins17 on Dec 12, 2021 12:31:20 GMT -5
dshanpnw by belt sander, do you mean expandable drum belts? I use one of them for my cabbing and can say with high certainty it is better for flat surfaces than a traditional cabochon making machine. If you get deeper into the hobby, you could use it for cabbing as well, which is also fun. Hope that helps!
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dshanpnw
fully equipped rock polisher
Member since December 2020
Posts: 1,149
|
Post by dshanpnw on Dec 12, 2021 14:42:37 GMT -5
dshanpnw by belt sander, do you mean expandable drum belts? I use one of them for my cabbing and can say with high certainty it is better for flat surfaces than a traditional cabochon making machine. If you get deeper into the hobby, you could use it for cabbing as well, which is also fun. Hope that helps! Hi Perkins17, yes, I did mean expandable drum belts, and using it for flat surfaces is my exact intentions. It certainly does help to know that you do use them. Thanks so much. |
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Post by perkins17 on Dec 12, 2021 15:24:49 GMT -5
dshanpnw by belt sander, do you mean expandable drum belts? I use one of them for my cabbing and can say with high certainty it is better for flat surfaces than a traditional cabochon making machine. If you get deeper into the hobby, you could use it for cabbing as well, which is also fun. Hope that helps! Hi Perkins17, yes, I did mean expandable drum belts, and using it for flat surfaces is my exact intentions. It certainly does help to know that you do use them. Thanks so much. Of course! Glad to help. I don't use mine for flats much but it works great for cabochons. I use a 15 inch vibratory flat lap for large flat surfaces but it won't produce as good of a shine. |
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Post by Rockoonz on Dec 12, 2021 18:55:33 GMT -5
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dshanpnw
fully equipped rock polisher
Member since December 2020
Posts: 1,149
|
Post by dshanpnw on Dec 12, 2021 22:29:46 GMT -5
I have looked at that one also and it would be great for some of the projects I have, but a cabber would be needed for most of the others. Thanks so much. |
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