Tien
off to a rocking start
Member since June 2016
Posts: 17
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Post by Tien on Jun 20, 2016 0:57:51 GMT -5
Hi All,
I'm brand new to the forum here and am hoping to get some feedback. I started rockhounding back in July of last year and since then I have learned to cab and facet. However, I am having issues with scratches on my cabs. I bought some used Cab King wheels from the local rock club in Vegas. The. Wheels were working great but I sent the 280 and 600 in to Johnson Brothers Lapidary to be resurfaced as they were both worn down through the resin on some parts of the wheels.
I got them back and I can't work the scratches out of my cabs for the life of me. It seems that the newly resurfaced 280 & 600 are leaving scratches that I can't work out with my used, but still good 1200 wheel. I know resin wheels need to be broken in but I'm not sure how much breaking in is needed. I ran them against a slab for 30+ min each. How much breaking in is needed? Could it be that my 1200 is worn down to the point it is cutting like a 3000 and its too big of a jump from the new 600? Should I send my 1200 in to be resurfaced too? Members of the rock club told me Johnson Brother's Lapidary was good for resurfacing, but I have seen mixed opinions from others online. Unless their quality is truly bad, I don't want to have to get them resurfaced elsewhere or have to buy new wheels...this hobby gets expensive fast lol!
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NDK
Cave Dweller
Member since January 2009
Posts: 9,440
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Post by NDK on Jun 21, 2016 9:37:52 GMT -5
I'm gonna bump this because I know someone here can answer your questions.
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Post by johnjsgems on Jun 21, 2016 9:55:32 GMT -5
We were doing a club show once and the club was demonstrating cab cutting with one of their Genies. JB owner asked them if they wanted some more free resurfaced wheels to try (he previously gave them two to try). They declined. They buy many Diamond Pacific Novas from me each year and say there is no substitute. Sometimes you do get what you pay for.
That said, 1200 is more of a pre polish. All visible scratches should be gone before you get to 1200. Your 280 should remove all the scratches from shaping with your 80 and 220 hard wheels. It usually is first wheel to wear out as it is doing more work then other Novas. Even maybe finishing small flat removal. You should see no deep scratches after 280. 600 removes 280 scratches only. A magnifier could be helpful. If you see deep scratches you need to back up a step or two. It is not uncommon to hear of Chinese diamond powder being not accurately graded so you can get wayward larger particles that make wheels or powder basically not usable. Johnson Brothers should stand behind the wheels if tey are not working. Good luck.
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Tommy
Administrator
Member since January 2013
Posts: 12,663
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Post by Tommy on Jun 21, 2016 12:14:20 GMT -5
My one experience with JB was very negative so I won't go too far into that. I use Nova wheels exclusively and you definitely get what you pay for.
On the subject of scratches I would echo what John said - after the 600 wheel all flats and scratches need to be gone. Anything other than a brand new 1200 isn't going to do much for you removing scratches. After finishing on the hard wheels up to 220 the heart of the process for me is three soft wheels 140, 280, and 600. One secret trick I use on harder stones - smooth agates etc. is I temporarily jump from 600 to my final polishing method and this will make any scratches I missed stick out like a sore thumb. I repeat this as often as needed 280/600/polish until I'm happy then move on to 1200 and finish it out.
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Tien
off to a rocking start
Member since June 2016
Posts: 17
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Post by Tien on Jun 22, 2016 17:42:37 GMT -5
Thanks for the responses! I like the 600 to polish idea. That will help. I did some testing on glass. The 600 worked out all of the scratches from the 280 but it left deep scratches itself. I ran it on my used 1200 wheel and it did nothing. The scratches remained even after nearly 10 minutes on the 1200 wheel! I then tried a brand new 1200 resin belt and it did work out the scratches but it took a very long time.
I called Yogi at Johnson Brothers and he was very helpful. He said to send in the 600 he resurfaced for me and to send in the used 1200 wheel. He would test both of them and would fix the 600 if it was contaminated. He also offered to resurface the 1200 for me free of charge as a courtesy. I'll post the results here in a few weeks after I send the wheels and get them back.
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The Dad_Ohs
fully equipped rock polisher
Take me to your Labradorite!!
Member since September 2012
Posts: 1,860
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Post by The Dad_Ohs on Jul 13, 2016 19:44:48 GMT -5
What did you use to break in the wheels?
We just changed the wheels in our club and I did the breakin with a chunk of Brazilian agate...
basically I make sure there is plenty of water on the wheels before I start and them jam the material against it.... I say jam because a light touch isn't going to work... it needs some pressure to conform to the shape of the slab, and I move it side to side along the wheel for about 1 minute. after that I washed the wheel down with a squirt bottle of clean water and a toothbrush, dumped and cleaned the pan and did the next wheel the same way... the outer layer of stuff they spray onto the wheels, even new wheels will come right off and contaminate all your wheel, especially on a genie which reuses the water in the tray. I did the same thing on my cab king except I used a hunk of seam agate as I had to do all the wheels (rez wheels are a pain to break in!!)but it works like a champ now and most of my stones look great at only 3000 grit instead of 14k.
Hard agate and plenty of water followed by a thorough cleaning seems to be the key for me.
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Tien
off to a rocking start
Member since June 2016
Posts: 17
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Post by Tien on Jul 26, 2016 13:28:34 GMT -5
I used a slab of agate and broke them in much longer than 1 minute.
So Johnson Brothers resurfaced the 600 for me and resurfaced by 1200 free of charge. It was nice of them. The 600 that came back IS better than the first one, albeit still very aggressive. I simply have to work the stone on the 1200 for a long time to smooth out the scratches from the 600. Maybe this will get easier as the 600 gets more use. The good news is that I can finally polish my stones and Johnson Brothers was accommodating.
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Post by johnjsgems on Jul 27, 2016 12:12:29 GMT -5
An old trick back in the old days was to sand one direction and turn stone 90 degrees for next step. That way you can tell what scratches you are dealing with. Also spend longer on each earlier step before moving up. In the silicon carbide days they said to sand as long as needed and then another 10 minutes. Diamonds are faster but same principal.
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The Dad_Ohs
fully equipped rock polisher
Take me to your Labradorite!!
Member since September 2012
Posts: 1,860
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Post by The Dad_Ohs on Jul 31, 2016 16:55:49 GMT -5
An old trick back in the old days was to sand one direction and turn stone 90 degrees for next step. I still do that but instead of switching grits when rotating the piece, I keep it on the same wheel and turn it 4 times before moving on. This way the scratches on the piece on non-directional and easier to remove with the next wheel, which is done the same way all the way to 14k.
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Greg Tidwell
off to a rocking start
Member since August 2016
Posts: 5
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Post by Greg Tidwell on Aug 18, 2016 16:14:14 GMT -5
Our club uses JB resurfaced wheels. I have noticed a problem, pretty consistently, with the 1200 wheels that we get back. Things cut grooves, even in hard materials. So I usually press much lighter and take more time. That usually does the trick.
We have also had two or three wheels fail in quick order. JB always fixes the problem.
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Post by orrum on Aug 18, 2016 17:05:53 GMT -5
Good trick John!
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