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Gadgets, Gizmos, and Dohickeys => Cutting, Grinding, Polishing => Topic started by: sealdaddy on March 29, 2015, 07:18:11 AM

Title: What is there about dry sanding with worn 600 grit SIC
Post by: sealdaddy on March 29, 2015, 07:18:11 AM
Sand paper or wheels that buffs up areas that other wet grits will not?
Title: Re: What is there about dry sanding with worn 600 grit SIC
Post by: Itsandbits on March 29, 2015, 08:04:51 AM
I'm pretty sure it is the heat that glazes it over but am a noob so can't say for sure; kind of works the same on nephrite
Title: Re: What is there about dry sanding with worn 600 grit SIC
Post by: lithicbeads on March 29, 2015, 08:28:09 AM
Other folks think that the water on the wheel makes a layer that hydroplanes the stone. Dry sanding while dangerous is very practical.
Title: Re: What is there about dry sanding with worn 600 grit SIC
Post by: sealdaddy on March 29, 2015, 10:58:10 AM
Other folks think that the water on the wheel makes a layer that hydroplanes the stone. Dry sanding while dangerous is very practical.
What about how it "solves" undercutting or orange peeling?
Hydroplaning would not cause those right?
And why 600, and not other grit surfaces?
Title: Re: What is there about dry sanding with worn 600 grit SIC
Post by: Gergis on March 29, 2015, 11:42:46 AM
With less to no water the grit is more aggressive i believe.
Title: Re: What is there about dry sanding with worn 600 grit SIC
Post by: lithicbeads on March 29, 2015, 05:17:41 PM
Undercutting requires a fast agressive cut but has to be fine at the same time. Traditionally the choice for dry sanding was a slightly worn 100 grit sic belt that is " loaded". To load a belt you dry sand an agate until the belt is totally white . The best cutter I have ever seen could dry sand large quartz crystal flats this way and get an amazing polish just with the one belt. A very delicate touch is needed as well as patience not to overheat the stone. The Richardson sander uses the dry sanding concept but at a very high speed so you need to go to finer grits then with an expendo as you have a lot less control.
Title: Re: What is there about dry sanding with worn 600 grit SIC
Post by: sealdaddy on March 29, 2015, 06:00:15 PM
I agree..."loading" is key
And I'll try loading with agate first.
I have been trying to do that with the material itself.
Thanks~
Title: Re: What is there about dry sanding with worn 600 grit SIC
Post by: lithicbeads on March 29, 2015, 06:23:24 PM
I have always seen it done with agate but that may not be crucial , just that it is loaded. with dry sanding with diamond the good work seems to end when it is loaded so I rinse the wheel and then sand with it as it dries and then sand with it dry until it is loaded and the sanding becomes much less efficient.