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Post by rmf on Jul 21, 2024 11:44:38 GMT -5
I know there are a number of you that cut a lot of cabs so I have a diamond question about your process.
First some diamond info. Plated wheels cut very fast for the first 100 - 150 cabs (I am referring to my 8" wheels) then they slow down to their normal speed for the bulk of their life then slow down again towards the end. Sintered wheels tend not to do this because the diamond is held in a metal matrix which only allows about 40% of the diamond to be exposed at a time. (So there is no real break-in period they cut like new out of the box till the diamond is gone.) This is why the equivalent of a 60 grit plated wheel is a 30 grit sintered wheel. Plated wheels have 95% of the diamond exposed for cutting right out of the box but as the wheel is broken in diamonds are ground down/removed so the wheels slows down. On a sintered wheel you get much thicker layer of diamond in a matrix but requires a coarser grit to get the same effect as the plated wheel due to how the diamonds are exposed. Nova type wheels tend to act more like a sintered wheel in the diamond is held in a plastic matrix and as such makes a more polished surface on the cab that an plated or sintered hard wheel.
So my questions are:
1. Are you using the default wheel configuration from the grinder manufacturer (like diamond pacific with 80 grit and 220 grit plated wheels and 280, 600, 1200, 3000 Nova wheels) or are you using other wheel configurations?
2. Will you share the wheel types you like to use if it is different from the default config above?
3. If you are moving from a sintered wheel grit to a soft plastic wheel where do you make the transition to the soft wheel? (between 220 and 280 like the example above)
4. When you make the transition from hard wheels (Plated or sintered) do you use the same grit to start in the plastic wheels or just jump to the next grit? What I mean by this question is that I am experimenting with a 600 grit sintered wheel. I am still using a 600 grit Nova wheel after to get a better finish before I go to the 1200. Have you experienced the same need?
I have been experimenting with a number of wheel configurations trying to optimize my cutting. I originally was looking for a sintered equivalent of an 80 grit plated wheel. This appears to be a 40/45 grit sintered wheel. I have not tried this yet it is just what my data is telling me and at $500-600 per wheel testing gets expensive. The 30 grit sintered is = to a new 60 grit plated both in grinding and in chipping. The 60 grit sintered wheel cut like a 120 grit plated wheel. currently I am using 30g, 60g, 140g 280g, 600g sintered, followed by 600g, 1200g, 3000g Nova wheels then go to conventional oxide polish for agates and true jaspers. other stones I go to 8000g nova. So at the transition from sintered to Nova I am using a 600 grit of each type to reduce my grind time on the finer grits.
I appreciate any info you can add from your experimentations. TIA
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Post by opalpyrexia on Jul 21, 2024 13:15:10 GMT -5
1. DP Genie Plated: 80, 220 Nova: 220, 280, 600, 1200, 3000 ... followed by Pixie Nova: 8000, 14000 |
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Post by rmf on Jul 21, 2024 13:20:31 GMT -5
1. DP Genie Plated: 80, 220 Nova: 220, 280, 600, 1200, 3000 ... followed by Pixie Nova: 8000, 14000 Thanks for the info. I am assuming you only polish with diamond since you go to 14k |
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Post by Starguy on Jul 21, 2024 13:47:27 GMT -5
The only deviation I’ve made on wheels was to replace 220 hard with 600 hard. It’s a little (not much) slower than 220 but when you get to the soft wheels, you make up the time almost immediately. I like this progression because it makes it easy to see coarse wheel scratches plus’s the 600 hard grinds much faster than you would think. Since it’s a hard wheel, it still leaves little faceted lines on the surface but the first sanding, (soft) wheel takes care of them easily. Since I can see the coarse wheel scratches easier than 220, It seems like I don’t end up backing up as often.
I’m guessing it won’t last as long as a 220. That’s my $ 0.02.
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Post by opalpyrexia on Jul 21, 2024 15:14:03 GMT -5
1. DP Genie Plated: 80, 220 Nova: 220, 280, 600, 1200, 3000 ... followed by Pixie Nova: 8000, 14000 Thanks for the info. I am assuming you only polish with diamond since you go to 14k Yes, just diamond. One edit: no 280. The Nova 220 replaced it. |
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rockinrenn
starting to shine!
Member since December 2023
Posts: 37
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Post by rockinrenn on Jul 21, 2024 15:22:23 GMT -5
Machine #1 - Plated wheels 60, 220, 300, 600 Nova 280, 600, 1200, 3000. Machine #2 - 8000, 12000, 50000 & 100000. The 600 plated is wonderful for scratch removal.
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Post by rockjunquie on Jul 23, 2024 7:08:57 GMT -5
You wanted abrasive, so here I am.
I use all diamond. 60 sintered, 220 hard, 220 soft, 600, 1200, 3000, 8000, 14000, 50 and sometimes 100. I have no issues going from 220 soft to 600 soft.
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Post by Rockoonz on Jul 23, 2024 10:24:49 GMT -5
The public shop at the Glendale Adult Center has 7 or 8 genies, and a couple are set up with non conventional wheels. I wish I had the time to get a membership and play with the different wheels to explore possibilities for our shop.
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Post by rmf on Jul 23, 2024 19:13:05 GMT -5
rockinrenn so when you leave the 600 plated wheel you go to 280Nova and then proceed on to the 600N and remaining soft wheels? I have been wondering about that transition rockjunquie & opalpyrexia I have been using a 220 soft after 220 hard but am looking at making a change to hard wheels down to 600 then proceeding to soft wheels. I am hoping to improve speed and reduce long term cost.
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Post by opalpyrexia on Jul 23, 2024 20:32:22 GMT -5
rockinrenn so when you leave the 600 plated wheel you go to 280Nova and then proceed on to the 600N and remaining soft wheels? I have been wondering about that transition rockjunquie & opalpyrexia I have been using a 220 soft after 220 hard but am looking at making a change to hard wheels down to 600 then proceeding to soft wheels. I am hoping to improve speed and reduce long term cost. Looking forward to an update when you feel that you have cabbed sufficiently to arrive at a conclusion. |
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lapidary1234
spending too much on rocks
"If you like rocks you can't be all bad!!" ~ old timer quote
Member since October 2021
Posts: 293
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Post by lapidary1234 on Jul 25, 2024 15:49:49 GMT -5
This is a topic I've wrestled in my mind for awhile and spent quite a bit of money experimenting with (hobbies aren't cheap lol)
You touched on some real good points that I made a mistake with.
Before I purchased my sintered wheels I asked in ALOT of places about the grit equivalency and the majority of answers I git were to go one grit size lower for sintered so I got a 60 grit sintered wheel in hopes it would cut like an 80.
My 60 grit sintered cuts more like a 120 or 140 even if I had to guess. It definitely cuts slower than an 80 grit galaxy. Everyone told me a 30 grit sintered would leave to many chips so I listened. That was my mistake but I had never used sintered wheels. I should have got a 3p grit as my intention was for a long lasting bulk removal wheel. I ordered a custom 8x3" so it was ERY expensive. I figured if it lasts for 20 years it would be worth it.
It is a great wheel, it just doesn't do what I had wanted it to. Also, and this is the big thing, the 8x3 is much wider at the bore so it barely fits on my raytech expandable drum machine. I actually found a used star diamond gp8 for a steal of a price and I will eventually mount the sintered wheels on it as the wheels mount between the bearings and have better support (that wheel weighs over 17 lbs).
I've also been warned against putting sintered wheels on a genie due to bearing stress and the older genies with 1/4hp motors are underpowered to begin with for how much weight they spin.
I also bought an 8x3 180 grit sintered to perform like a 220. This one seems more in line with my expectations but it really probably cuts like a 240 or finer.
Now on to your question about unconventional wheel setups...
I was still really looking for something for bulk removal. I decided on a 60 grit textured wheel from kingsley. These are much more affordable than sintered wheels and it cuts incredibly aggressively! Now I've heard that while textured wheels cut faster that they also wear out faster. This remains to be seen as I just got it recently. But all in all I'm incredibly impressed with how it performs!
The one caveat regarding "off brand" wheels...Even with all possible combinations of spacers available the wheel just wouldn't snug up when bolted on. I ended up using a rubber washer similar to an oil pan bolt gasket. This worked but I decided to mention it to kingsley as it was like 1/64" too small. Kingsley said diamond pacific does that intentionally so you have to use their products.
I currently have my 60 grit textured wheel in place of the 80 galaxy. Someday I will get another right hand spindle and put the 60 textured along with a 60 nova, and 140 nova. Just not ready to spend the money yet.
As far as dropping back down in grits, I have been using endplates lately and I will go on a metal lap to 150 and then drop down to a nova 140. Sometimes I've gone to a 320 metal lap and drop down to a 280 grit nova. This works nicely and helps get rid of the scratches from the metal wheels/discs.
I have read discussions about going all the way to 600 metal (skipping the 220) but in my experience the 600 doesn't actually get rid of the deeper scratches, just makes them smaller. I know others swear by it, that's just my experience.
Hope I've answered your questions if you made it this far!
Cheers ~ Josh
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rockinrenn
starting to shine!
Member since December 2023
Posts: 37
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Post by rockinrenn on Jul 25, 2024 15:58:42 GMT -5
rockinrenn so when you leave the 600 plated wheel you go to 280Nova and then proceed on to the 600N and remaining soft wheels? I have been wondering about that transition rockjunquie & opalpyrexia I have been using a 220 soft after 220 hard but am looking at making a change to hard wheels down to 600 then proceeding to soft wheels. I am hoping to improve speed and reduce long term cost. I usually skip the 280 soft wheel if I use the 600 hard wheel. It mostly depends on the stone and whether I'm pleased with the results at that point. Hard stones may require the 280 for scratch removal. |
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lapidary1234
spending too much on rocks
"If you like rocks you can't be all bad!!" ~ old timer quote
Member since October 2021
Posts: 293
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Post by lapidary1234 on Jul 25, 2024 20:19:46 GMT -5
rmf, In response to where I make the transition from sintered to soft wheels.... I have the sintered wheels at my workshop (not home). Again as I mentioned earlier I have a 60 grit and a 180 grit sintered. The other machine I have there has two 8" expandable drums. I use "agglomerate" silicon carbide belts with it. I usually transition from the 180 sintered (which cuts probably like a 240-280 in reality) to a 240 grit sc belt or sometimes to the 400 sc belt. There is a good chance the 240 sc belt is a coarser grind than the 180 sintered but its hard to tell. Most of the time the jump from the 180 sintered to the 400 agglomerate sc belt works well. I also posted a question/comment somewhere about a disclaimer I read in the MN lapidary supply catalog that said something to the effect of sc belts performing much different than diamond. The exact quote is: "Diamond belts cut much faster than silicon carbide belts. Also please not that the finish is different on the two types of belts. As a rule of thumb a 600 mesh silicon carbide belt produces the same finish as a 1800 mesh diamond belt." Regarding this I'm not sure i agree in my experience. Yes diamond definitely cuts faster and makes less mess. Is the finish really that different? I'm not sure, I get an excellent finish using sintered wheels and silicon carbide belts but to be totally transparent I can only get the agglomerate belts up to 1200 grit so I have bought a 3,000 grit diamond belt. I guess I "technically" finish with diamond. The last sentence in the quote is the one I have a hard time believing. That a 600 grit silicon carbide belt cuts like an 1800 diamond. This has not been my experience. Occasionally I start to get a shine on my genie after the 1200 diamond stage. I have not started seeing a shine after the 600 silicon carbide belt. If you're trying to match a sintered wheel with an 80 grit electroplated wheel I think you're probably close with thinking 40-45 grit but possibly even go with a 30. Baltic Abrasive (where I got my sintered wheels from) told me they can do any grit requested. If your goal is bulk removal id definitely recommend a 30 grit, but like I said earlier the textured wheels will really chew through material!
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Post by Rockoonz on Jul 25, 2024 21:12:20 GMT -5
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Post by rmf on Jul 26, 2024 10:43:22 GMT -5
lapidary1234 Thanks for that response. when I moved to diamonds a long time ago it was very disappointing that (hot water agates like Brazilian and Lake Superiors) I did not get the finish i expected at 600 grit diamond. as you say 600 diamond and 600 SiC do not produce the same finish. I had to go finer on diamond to get equal results, as you said. What I have found is that on hot water material as referred to above there is a shine that begins at 600(Nova) but on the Paint Rock Agates (cold water formation) you do not get that same sheen until you get to 1200(Nova) by the time you get to 3000(Nova) you can't tell the difference in finish. I have a Baltic Abrasives 30 Grit sintered wheel and it cuts 13% faster than a broken in 60 grit plated wheel. I did not have a brand new out of the box 60 grit plated hex wheel to test for comparison but I had a Galaxy Hex that I had ground 500-700 stones on mostly as a material hogger so it was cutting about average for a 60 grit plated Hex wheel. I expect that if the 60 grit was New it would equal the 30grit sintered close enough you could not measure. After my initial testing of the 30 grit, I have been roughing out preforms on the 60 grit hex to use it up, it is worn down enough now that it nolonger chips when grinding agates. My original plan was to never buy another wheel since the Sintered costs within a few $$ of what the plated wheel costs. I have not heard other sources share what you said above and it agrees well with my exp as well but I did not have some of the info you shared. Thanks!!!
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lapidary1234
spending too much on rocks
"If you like rocks you can't be all bad!!" ~ old timer quote
Member since October 2021
Posts: 293
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Post by lapidary1234 on Jul 26, 2024 15:14:42 GMT -5
Yep, thats the kind I used. The ones I have have a little wider rubber but are 1" bore! |
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rocknrob
has rocks in the head
If Costco only sold slabs in bulk...
Member since May 2024
Posts: 611
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Post by rocknrob on Jul 27, 2024 12:03:53 GMT -5
This is VERY enlightening although I don't have a cabbing machine yet. This is particularly why I'm starting to sell slabs in order to buy one  . Right now I've got a progression of between 60-180 hard and then I use the 220 sponge lap to smooth out the facets if there are any. I have been going through the progression of 320,600,1200 and then 3000, finishing on 15,000 but I'm getting a slightly hazy shine on my final cabs. Or at least the ones that are hard enough to take a good shine. I was thinking of inserting a mid grade polish before going to the 15,000. I've got the paste for it, just need to apply it to one of my felt discs. |
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lapidary1234
spending too much on rocks
"If you like rocks you can't be all bad!!" ~ old timer quote
Member since October 2021
Posts: 293
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Post by lapidary1234 on Jul 27, 2024 14:21:55 GMT -5
This is VERY enlightening although I don't have a cabbing machine yet. This is particularly why I'm starting to sell slabs in order to buy one . Right now I've got a progression of between 60-180 hard and then I use the 220 sponge lap to smooth out the facets if there are any. I have been going through the progression of 320,600,1200 and then 3000, finishing on 15,000 but I'm getting a slightly hazy shine on my final cabs. Or at least the ones that are hard enough to take a good shine. I was thinking of inserting a mid grade polish before going to the 15,000. I've got the paste for it, just need to apply it to one of my felt discs. This may sound unconventional but you could experiment with making a slurry using the typical micro alumina polish kingsly or rock shed sells for tumbling. It is typically 1-3 micron (8,000-13,000 grit). I have been using "rapid polish #61 from MN lapidary supply with great results if I want an extra "pop". It is .25 micron (75,000) so stones need to be prepped properly (i take them up to 50,000 grit wheels for this). have. Is a micro alumina polish also. The only other thing that might be leaving them hazy would be jumping from 220 to 320 *might be too large of a jump, typically people go to a 280. Although I think if the issue is from that early in the process you would be left with scratches not a haze. |
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. Right now I've got a progression of between 60-180 hard and then I use the 220 sponge lap to smooth out the facets if there are any. I have been going through the progression of 320,600,1200 and then 3000, finishing on 15,000 but I'm getting a slightly hazy shine on my final cabs. Or at least the ones that are hard enough to take a good shine. I was thinking of inserting a mid grade polish before going to the 15,000. I've got the paste for it, just need to apply it to one of my felt discs.
