jamesp
Cave Dweller
Member since October 2012
Posts: 36,165
|
Post by jamesp on Jan 1, 2013 21:27:37 GMT -5
$29.95 for 4 inch-fits 4.5" angle grinder. $49.99 for 7 inch for large angle grinder 50/60 grit diamond.
|
|
itsandbits
freely admits to licking rocks
Member since March 2012
Posts: 825
|
Post by itsandbits on Jan 1, 2013 23:29:52 GMT -5
links? :<)
|
|
herchenx
Cave Dweller
Member since January 2012
Posts: 3,360
|
Post by herchenx on Jan 2, 2013 0:50:08 GMT -5
|
|
herchenx
Cave Dweller
Member since January 2012
Posts: 3,360
|
Post by herchenx on Jan 2, 2013 0:50:51 GMT -5
James I'm always happy to show my ignorance, so what would one do with these diamond cups?
|
|
itsandbits
freely admits to licking rocks
Member since March 2012
Posts: 825
|
Post by itsandbits on Jan 2, 2013 1:52:29 GMT -5
thanks John I was just wanting to make sure we were looking at the same thing I was thinking of because I buy a diamond grinding wheel locally but it is smooth 320 grit the same size. I think my cost is about 12. can. but these ones look a lot more agressive and would be good for large flat stones like counters i think.
|
|
|
Post by Rockoonz on Jan 2, 2013 2:51:58 GMT -5
That's what it's for, large flat surfaces. Say if you had a large Petwood slab or something too big for a genie Lee
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,165
|
Post by jamesp on Jan 2, 2013 7:27:26 GMT -5
Sorry for being ambiguous.I pre grind stones before tumbling.Most of these corals were very jagged and broken with a hammer.The pre grind saves 4-8 weeks in the coarse grind process.The ones toward the end of the photos that are tumbled were in coarse grit for about 10 days.I could not have gotten some of those that rounded in 3 months.I can pre grind them quick with that diamond cup.I use a 4 and 1/2 inch $29.99 Harbor FReight angle grinder w/the 4 inch cup.Tie wrap the grinder to a board or something so you do not have to hold it.I can pregrind 5 pounds in 10-30 minutes.The cup lasts a long time-even dry.Best for agates and tougher matl. www.flickr.com/photos/67205364@N06/sets/72157632093236746/with/8216273458/
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,165
|
Post by jamesp on Jan 2, 2013 7:44:30 GMT -5
This wheel has lasted me years.I used this rig to flatten the bottom of 3-8 inch agates so i could glue them to a base.And for pre shaping before tumbling.Lots of dust and watch your loose clothing,fingers at 10,000 rpm angle grinder speeds-PLEASE.Grind outside...
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,165
|
Post by jamesp on Jan 2, 2013 7:50:59 GMT -5
|
|
|
Post by johnjsgems on Jan 2, 2013 9:32:13 GMT -5
They are made to use with wet angle grinders. You can use them for contouring also but not steep curves as they are flat. For contouring (depending on how soft the matrix is) you need a lot of water and very light pressure (like floating over the surface) or they wear out fast.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,165
|
Post by jamesp on Jan 2, 2013 10:02:03 GMT -5
Hi John Happy New Year to you.These are for dry use.Look at the Harbor FReight link above and click on one of the wheels.In the specs it says for dry use.I bought my 4 inch wheel about 5 years ago. They were $80 dollars then.The oversea clan has of course brought the price down.I must have 3-400 hours dry use on this wheel and about that many are still left on it.They are acceptable for use on a standard 4.5 inch angle grinder,but can definately be used on an expensive water center feed 4.5 inch angle grinder and should really last a long time. My power bill for running my big tumbler has gone down a lot since i shortened the coarse grind so much.This new fandangled technology was developed with the advent of granite counter tops.Harbor sells a dust hood for this monster dust maker too.
|
|
|
Post by mohs on Jan 2, 2013 11:19:35 GMT -5
interesting thread guys Now this what I got from an industrial yard I think these cups go on a hydraulic table for polishing granite counter tops The guy gave me this wheel for free as an experiment I was hoping to attach it to my Lortone see if it would do some grinding but I have to get a bushing the hole is metric and I don't have a reducing bushing...yet to experiment anyway its a 5" wheel 1" thick the Yard as a whole box of various grades/grits I was thinking it would be a good purchase to use on angle grinder? what do you think? Attachments:
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,165
|
Post by jamesp on Jan 2, 2013 11:55:16 GMT -5
Is it diamond?It does not seem to be.If it is not diamond it may not cut agate well.
|
|
herchenx
Cave Dweller
Member since January 2012
Posts: 3,360
|
Post by herchenx on Jan 2, 2013 12:28:40 GMT -5
Thanks James and all for explaining. That would certainly be cheaper on a pre-grind that my galaxy diamond wheels! The dust would be an issue though, and here it is cold enough in the winter that I don't want to be standing outside for any length of time!
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,165
|
Post by jamesp on Jan 2, 2013 13:17:50 GMT -5
John,i agree.Colorado cold is cold!That grinder is one of my favorite devices.It kind of revolutionized my tumbling.
|
|
|
Post by mohs on Jan 2, 2013 23:39:01 GMT -5
well I think it diamond, james no one in the Yard really knew what they were use for
but my intuition tells me they are diamond I won't really know till I spin it
but they had about 40 of these wheels and the various ones were marked 120, 220 330, 400, 600 ect... and they were different colors to
hope they are S/C diamond and if they are I'll buy them if I get good deal I can incorporate them in some fashion...no angle grinder ?
|
|
|
Post by johnjsgems on Jan 3, 2013 9:00:46 GMT -5
No reason you can't use dry wheels wet. They make them dry so workers can touch up bull noses and other things in someone's house without a flood. The flat wheels and cut off wheels Barranca carries (green colored frames) are all rated dry. They really last a long time wet and no dust to kill you.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,165
|
Post by jamesp on Jan 3, 2013 10:55:08 GMT -5
The diamond matrix is 5 MM thick on this 4 inch wheel John.Maybe 3/4 inch wide.Since pre grinding tumblers i have worn a saddle about 2 MM deep.It give a great curve for rounded edges.I took some of your advise by soaking the stones in a water bath next to the grinder and dipping the stone every grind stroke.It greatly reduced the dust.And wear.That is one tough grinding wheel.If it was turning slower and had finer grit i could preshape cabs for tumbling.50 grit and 10,000 rpm chips as much as it grinds agates...A 200 grit on an 1800 motor would be killer shaper for finer work let the tumbler do the finish done.Have you seen this type wheel in 200 grit mountable to a walmart grinder 3600 rpm is fine i would buy now?
|
|
|
Post by johnjsgems on Jan 3, 2013 11:00:30 GMT -5
I have not seen any cup wheels with 200 grit. They are all for shaping so usually 50 grit or so. The BD flat grinding disc is listed as "fine" but it is 120 grit. It is also rated dry.
|
|
jamesp
Cave Dweller
Member since October 2012
Posts: 36,165
|
Post by jamesp on Jan 3, 2013 13:47:04 GMT -5
Thanks for that info Mr John.I looked at a lot of diamond cups and the 120 is the finest i could find too. I have one on another machine.I will give that one a try if i can figure 5/8 11 conversion to 1800 motor shaft of some sort.It would also be great for more delicate pregrind on tumblers(less chipping).Dang,i wish Barranca had a 200.They sell great quality.
|
|