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carla
 #1 
Hello all. This is my first time on here. Glad I found you. My question is "how can I tell when to replace the Nova Wheels on my Genie"? What I want to know is what to I look for on the wheel. I am new at cabbing. I know i will see a difference in the cabs themselves of course but I want to know what the wheel will look like when it is worn.
I also want to know how hard I am supposed to be pushing on the rubber backed wheels. I am afraid that I have been pushing to hard and have worn my wheels out faster as a result. When they told me I can push hard on those last wheels I took it to heart and being a very heavy handed person I now am wondering if I have been overdoing it. My eyesight is not what it used to be and is getting worse so I don't trust just looking at the cabs. I use my machine a lot since I am making cabs to sell. I make about 6 to 8 a week. I just don't have anything to compare my use with as i cannot get to my club any more. I appreciate your help...
dave t.
 #2 
Hi Carla - Welcome to the wonderful world of cabbing! That is a realistic question and about the first most common inquiry as to 'when' your wheel or band is wearing out.

One of the most common events of a new cabber is to be a little impatient and not knowing just how good in shape your grit is; just bear down on the wheel. Unless you have training by an 'experienced' cabber the basis of what is normal does not surface until you gain more experience.

Essentially; the rule of thumb is to let the wheel do the work without extreme pressure. If you are finding high pressure is needed; you are either not grinding out all of the scratches from the twice previous grit, or else your grit is worn down. Of course this is assuming your water drip is sufficient to clean up the wheel during grind.

A lot of variances at this time come into play.
What material is your grit? silicon carbide or diamond
What material are you grinding? agate, corundum, quartz, ?

Of course diamond is the overall grit of choice. S/C will wear down faster and have to be replaced. I have found that on my bands, after they have worn down to the point of not feeling anything on my fingernail while running dry, I can stop, dry the band, apply a coating of Vaseline and thin it down with a razor blade, apply either a minor dot of dry or paste diamond around the wheel, smooth it out with a razor blade and then take off again after applying a smooth stone to embed the diamond during a 'dry run-in'.

You would be surprise how much nicer the grind then is. Of course use the same grit sizes as were on the band previously! I always go to diamond following a silicon band as it lasts so much longer.

As for solid wheels or discs, I have heard of folks applying an epoxy and then embedding diamond. But after several years of cabbing and faceting I have never needed to do this. On cabs I stay with bands after shaping in with a cheap corundum grinding wheel and followed by a 100 grit diamond. From there I use the bands with great success. My most common stone is agate, of which varies a lot in Mhos depending on its Momma & Poppa. LOL

Hopefully this will help ya out. There is a lot to learn in the lapidary processes with a lot of variables. As everyone else states, do whatever it takes for your needs.

Good grinding, dave t.
Joe D.
 #3 
Carla,

The Genie wheels will last a long time with the use you mention. I make thousands of Cabs before mine need to be replaced. The metal ones seem to be indestructible and have lasted me over 12 years so far. The other "Nova" type wheels, with the cushion like backing, don't last me but 5 to 8 years. If you buy replacement wheels make sure to get genuine replacements from the manufacturer. The other makers put out junk that won't last long at all. The replacement wheels have poorly bonded material that will tear and wear prematurely. Diamond Pacific still makes the best wheels for the Genie. I have worn out a replacement wheel in 2 months and swore at them at by Diamond Pacific brand. Generally, in my experience, any material under 7 on the MOHs scale will build up on the wheels. If you cut harder material then there will be no appreciable buildup.

The harder the material you work on the longer it generally takes to get those tiny scratches out. Also the darker the material the more the scratches show up when the material gets dry and you are looking to do something with them.

You can buy "Dressing" sticks but I have been using an old piece of concrete brick for years that works better then the dressing sticks. You just run it around on the wheels for a few minutes and it reveals the new Diamond and abrasive material, almost like new. It works for the saw blades also.

Joe D.
Jack Cole
 #4 
Carla;


The one most impotent part that has not been said,


reverse the wheels so the back ramp that builds up is cut down to expose the old diamond.

and to save the wheel`s life time. only use Obsidian to sharpen the diamonds cutting face.


Jack
Joe D.
 #5 
If you use the Genie wheels properly and work from one side to the other there is no uneven wear of the Diamond surface. This is the proper method to make cabochons anyway to keep from making cupped or uneven cabs. You should never leave the object in one place that you are working on the wheels.

Obsidian will never sharpen Diamond since it's exponentially softer. The idea is to remove the build up of softer material that clogs up the Diamond and keeps it from doing it's job. The reason to "Dress" the wheels and blades is to remove build up and expose the Diamond that is bonded to the wheel. You are not really exposing new Diamond unless you remove old Diamond first. The normal use of the equipment in the proper manner removes some Diamond over time. When you run out of Diamond, you need new wheels.

Joe D.
phil
 #6 
Dave t..

Please explain "bands"??? Do you mean cotton belts on an expanded wheel or ???

Thanks!
Phil
dave t.
 #7 
Bands - yes, various woven material with some sort of coating in order for the grit to adhear to them. They slip over the expanding wheels and can be exchanged easily. dave t.
Phil
 #8 
Thanks Dave T.

When you change them, how well does the expanding wheel need to be cleaned or not at all?

Do they make them for 6 inch by 1.5 inch drums? Who sells them? I've never seen them locally, although I read some posts here about charging some cotton ones, etc.

Thanks again,
Phil
dave t.
 #9 
Phil - http://www.kingsleynorth.com/skshop/search_results2.php?catID=814 Just wipe down the expanding drum, it shouldn't be dirty. dave t.
carla Olsojn
 #10 
OMGosh!! I should have joined one of these a year ago!! But this is the simplest I have found - so here I am. Thank you so much for all the answers and info. I will be reading and coming to understand all of it and come back with more questions, no doubt. I just wanted to thank Dave, Joe, Jack and Phil. My lordy I am in info heaven. See yall soon...Carla
Phil
 #11 
Thanks Dave!

Welcome Carla!
Phil
 #12 
Looked at Kingsley... those are silicon carbide.. I thought you were referring to cotton type belts that you charge with whatever grit you wanted...

Thanks!
Patty Halas
 #13 
Just received new replacement wheels for my Genie. So happy! But forgot how to take OFF wheels. What tool do I use???🙋🏼
Mike Streeter
 #14 
Patty,

Click on the following link for the Genie's manual:

http://api.ning.com/files/SejDF0kW9biHZTAcCT2RNlPsCX2rvw8uZy5TWoKLof3GhHmITWYLEJdlyosxnnif7X*qgaP*CXMEL0*DtbfnrxMDlrOu8CxC/GenieManual.pdf

I suggest that you download and save a copy of the manual for future use.

Good luck!

Mike
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