bitterbrook
noticing nice landscape pebbles
Always remember STEP NUMBER ONE!
Member since September 2006
Posts: 99
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Post by bitterbrook on Nov 9, 2018 9:22:48 GMT -5
If you've been a student of mine at William Holland, you will recognize these techniques taught in my class... 1) Light is necessary to see what you're cutting. 2) Magnification is necessary to see what you're cutting. 3) Light and face are in the same general area, so you have lots of light on your work and you can see what you're cutting. 4) Cabochon is being worked at the very bottom of the wheel so you can see what you're cutting (OK, so I'm starting to polish... but pretend the cab was at the 280 wheel and in the same place).
Yes, the photo is of me. I am sad today because I am not going back to teach another class until next August!
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Tommy
Administrator 
Member since January 2013
Posts: 12,968
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Post by Tommy on Nov 9, 2018 10:07:46 GMT -5
If you've been a student of mine at William Holland, you will recognize these techniques taught in my class... 1) Light is necessary to see what you're cutting. 2) Magnification is necessary to see what you're cutting. 3) Light and face are in the same general area, so you have lots of light on your work and you can see what you're cutting. 4) Cabochon is being worked at the very bottom of the wheel so you can see what you're cutting (OK, so I'm starting to polish... but pretend the cab was at the 280 wheel and in the same place). There's only one thing missing sir! The older we get the MORE light and MORE magnification is necessary  For me personally I worry about cabbing in my optivisors because I feel it gets me too close to the mineral spray for breathing safety. I tend to only do it when working on a difficult material that I am fight with scratches on. For the most part I favor a set of 1.50 magnification safety glasses. |
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Post by parfive on Nov 9, 2018 10:43:25 GMT -5
Cabochon is being worked at the very bottom of the wheel so you can see what you're cutting I’ll take exception to that description. Most of my cabbing takes place between three o’clock and four o’clock on the wheel. I doubt it ever gets to four thirty, never mind the very bottom of the wheel. Lower half or below the equator, fine, but not at the very bottom. |
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gemfeller
Cave Dweller 
Member since June 2011
Posts: 4,049 
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Post by gemfeller on Nov 9, 2018 10:57:42 GMT -5
Cabochon is being worked at the very bottom of the wheel so you can see what you're cutting I’ll take exception to that description. Most of my cabbing takes place between three o’clock and four o’clock on the wheel. I doubt it ever gets to four thirty, never mind the very bottom of the wheel. Lower half or below the equator, fine, but not at the very bottom. I totally agree. And I also agree with Tommy's observation about magnification and aging.  |
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QuailRiver
fully equipped rock polisher
Member since May 2008
Posts: 1,640
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Post by QuailRiver on Nov 9, 2018 12:04:45 GMT -5
There's only one thing missing sir! The older we get the MORE light and MORE magnification is necessary For me personally I worry about cabbing in my optivisors because I feel it gets me too close to the mineral spray for breathing safety. I tend to only do it when working on a difficult material that I am fight with scratches on. For the most part I favor a set of 1.50 magnification safety glasses. Yeah I know what you mean Tommy. And sometimes the swarf can taste a little funny too. It won't improve the health risks of inhaling the mist but it was once suggested to me that adding a little aged Scotch to the water tank can make it a more pleasant experience.  Larry C. |
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Post by rockjunquie on Nov 9, 2018 12:14:17 GMT -5
Cabochon is being worked at the very bottom of the wheel so you can see what you're cutting I’ll take exception to that description. Most of my cabbing takes place between three o’clock and four o’clock on the wheel. I doubt it ever gets to four thirty, never mind the very bottom of the wheel. Lower half or below the equator, fine, but not at the very bottom. Yup. |
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Tommy
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Member since January 2013
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Post by Tommy on Nov 9, 2018 13:11:12 GMT -5
I’ll take exception to that description. Most of my cabbing takes place between three o’clock and four o’clock on the wheel. I doubt it ever gets to four thirty, never mind the very bottom of the wheel. Lower half or below the equator, fine, but not at the very bottom. I know this isn't what he was talking about, and I'm not sure if I'm the only free-hander here but after I quit using dop sticks all together two years ago, I hold each cab in both hands under the wheel at around the five to six-thirty position for all of the repetitious steps 280-50k. This does NOT include the grinding wheel stages where precise nearly straight-on control is required. I find this position to be much safer on my fingers than trying to go in straight at 3-4 oclock with knuckles and fingertips exposed. |
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Post by Pat on Nov 9, 2018 13:21:35 GMT -5
Agree. I don’t use dop sticks either.
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Post by rockjunquie on Nov 9, 2018 13:41:02 GMT -5
I use green alligator tape where I get bit.
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gemfeller
Cave Dweller
Member since June 2011
Posts: 4,049
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Post by gemfeller on Nov 9, 2018 14:51:49 GMT -5
The only times I cut with dipsticks is when polishing the backs opal doublets and cutting stones with steep girdles and high domes. Every other step, including grinding, I do strictly by hand. I used to have occasional fingerprint loss and minor injuries during grinding but over the years I've cut many tiny opals entirely without dops and have developed a lot of dexterity. I still have my fingerprints and don't have to keep superglue nearby to "bandage" my fingers. That's probably not the best way for beginners to learn cabbing but we all develop our own techniques over time.
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bitterbrook
noticing nice landscape pebbles
Always remember STEP NUMBER ONE!
Member since September 2006
Posts: 99
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Post by bitterbrook on Nov 9, 2018 14:56:10 GMT -5
Sorry, I need to clarify! By the "bottom" of the wheel, I meant, the bottom-most part of the wheel "that I can see." If I draw a line from my eyeball to the bottom visible part of the wheel, this is where I need to cut. Forward of that, or behind that point, I can't see what I'm cutting.   One of my classroom mantras is, "If you can't see what you're cutting, expect appropriate results." |
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Post by hummingbirdstones on Nov 9, 2018 23:29:38 GMT -5
You have not met my husband. He cabs without a dopstick and domes under the wheel with one hand. I can't do it that way -- arthritis is setting in and my fingers "stick" in a position if I'm holding a stone in my hand for too long. Dop sticks for me, but I use all parts of the wheel, depending on what I need to do to the stone.  |
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Post by vegasjames on Nov 10, 2018 2:11:33 GMT -5
If you've been a student of mine at William Holland, you will recognize these techniques taught in my class... 1) Light is necessary to see what you're cutting. 2) Magnification is necessary to see what you're cutting. 3) Light and face are in the same general area, so you have lots of light on your work and you can see what you're cutting. 4) Cabochon is being worked at the very bottom of the wheel so you can see what you're cutting (OK, so I'm starting to polish... but pretend the cab was at the 280 wheel and in the same place). There's only one thing missing sir! The older we get the MORE light and MORE magnification is necessary  And a little Viagra in the water to keep the rock hard. |
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Post by vegasjames on Nov 10, 2018 2:16:18 GMT -5
Agree. I don’t use dop sticks either. I don't either. Never even tried. |
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Post by hummingbirdstones2 on Nov 10, 2018 11:15:01 GMT -5
Yeah, I'll get in here too. Bitterbrook, your diagram for seeing what you're cutting is right on the mark for precision cutting. That's absolutely how I cut the girdle/dome transitions. No sticks, though, except for old-style high domes and tiny bits.
The daughter-in-law of the local college lapidary instructor even commented on the girdles Robin and I cut. We had taken his classes, to socialize with friends and cutters, and he'd even show them to the class. So yeah, that diagram shows how to get precise results. The cutter has to be able to see the exact point where the stone meets the wheel. That ability is diminished if the face of the wheel is in the background. Must be able to see beyond that point to keep it precise.
For hogging off excess material and rough shaping I hardly look at a stone anymore. After a while it's possible to develop a feel for a high spot or a flat. Polishing stages are also less critical - as you alluded to - except for being careful not to roll the edges of the dome.
The re-cut I did on this opal forum.rocktumblinghobby.com/thread/85082/first-opal-parcel?page=1&scrollTo=1019295 was done freehand, and when it was done it fit right into the 14x12 template. Okay - the size was a bonus, but I knew the shape was right. Last part of that one was getting a hump out of the girdle at about 11 o'clock. If you imagine a cam lobe, it's possible to feel a hump or high spot like that by holding the stone firmly in one position and moving it up and down the face of the wheel.
Tommy - your point on optivisors is a good one. If the focal length on a visor is too short I get a sore neck/back from being hunched over without ever realizing I'm in that position. I finally started using bifocal readers combined with a cheap visor with interchangeable lenses that flip up out of the way. Get normal vision and three different magnification options using that combo.
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Post by rockjunquie on Nov 10, 2018 12:08:06 GMT -5
There's more than one way to skin a cat. I dop and I mark the cab on the front. I use that dopped preform to shape on the 80. I use the 80 grit to do all my forming. The 220 galaxy just removes scratches. I got a new and very aggressive 80 grit. I just finished a wafer thin round OJ that came out perfect. So, while I may not do things the "correct" way, I'd say I am doing pretty good. I've seen a lot of ways to cab and I'm sure I do it all "wrong", but I get it done, done right and done fast. I use the wheel between 3:00 and 4:00. Not to argue, I haven't been doing this as long as some of you, but it just goes to show- there is no "right" way.
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Post by hummingbirdstones2 on Nov 10, 2018 12:25:08 GMT -5
Well said, Rockjunquie!
I would never have started cutting if not for what someone told me at a show once. I told him all the different grits and compounds and such seemed really complicated. He told me this one thing - "When you finish a stone, if it's smooth and shiny, you did it right."
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Tommy
Administrator
Member since January 2013
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Post by Tommy on Nov 10, 2018 12:43:36 GMT -5
... it just goes to show- there is no "right" way. Well said indeed. My cabbing methods (dare I say skills?) are constantly evolving. If you had told me two years ago that I'll be free-handing everything, or more recently told me I'd soon becoming heavily dependent on an expando wheel and SiC belts, I would have laughed at the notions. I was the ridiculous dopping 'King' (or was it the 'fool' jester?) at one point - as demonstrated in this May 2016 post - and it was imperative that I break myself of the habit. One day I stopped and truly marveled at how much time I was wasting on unfinished crap. I still have several "Island of Lost Cabs" jars filled to the brim.  |
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Post by rockjunquie on Nov 10, 2018 12:49:07 GMT -5
LOL! That looks familiar. I learned doing it freehand, but because of arthritis, and long nails, it didn't work for me. I may switch back if I ever find a medicine that works, but as it is, I can't do freehand. Which is weird because I know you have arthritis, too, and freehanding is easier for you. Go figure. I guess for me it's like hummingbirdstones Robin says, my fingers lock up. |
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Tommy
Administrator
Member since January 2013
Posts: 12,968
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Post by Tommy on Nov 10, 2018 13:00:22 GMT -5
Which is weird because I know you have arthritis, too, and freehanding is easier for you. Go figure. Yeah, that's a point worth expanding on - it was my sore wrists that first had me searching for a better way. Holding the stick and going round and round took a major toll on my wrists, not to mention the amount of pressure I was using was wearing out Nova wheels like crazy. Now that I've settled into freehanding I've learned how to hold the cabs in a sort of natural position with palms up facing the bottom of the wheel and aside from keeping a firm grip on the cab and rotating it etc., the main motion is generated at the elbow and shoulder. What gets my arthritis flaring up and my fingers beat up and hurting is the initial rough grinding. That has always been a freehand step for me. I never learned to glue a preform to a stick then start grinding for a girdle. |
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