A few months ago I tried a Crystalite plated flexible lap in 400 grit and then later I picked up a 600 and 1800 grit Crystalite resin flexible laps. The 400 grit lap is astoundingly aggressive while the others are slow they aren't mind numbingly so. The 400 grit lap also improved the final shine significantly with the loose grit I had been using as did the 600 and 1800 laps.
I'm not sure why this wasn't clear to me before but loose grit, even if coarser, is very non-aggressive. I'd say it is better for polishing but very coarse grit could put scratches in the material.
These laps seem to not be very popular compared to the diamond resin wheels. I will probably replace the 600 and 1800 laps with wheels when they wear out as they seem to have a much shorter lifespan than the plated lap.
Also I've given in and bought a 80 grit diamond wheel. The 100 grit carbide wheel was driving me nuts. First it was slow enough that my mind would eventually wander off and I made stupid mistakes. Second, as it wears down and gets smaller it gets even slower. When it started to take near 2 hours to rough out agates I had enough. Well, let me tell you, that 80 grit wheel is no joke. I roughed out an agate the other day in about 25 minutes. It blasts though quartz. I'm well pleased. A good and bad thing is that it gouges (as coarser diamond grits do). This is good because those gouges tell me exactly where to apply the 220 wheel. The bad thing is I need to leave more work for the 220 wheel because not only does it gouge it also chips, so I can't get too close to the finished size on that wheel.
I had been of the opinion that I'd stick with the 220 grit wheel in carbide as I use it for a pretty short step. But two things have changed my mind 1) I have to leave more work for this wheel and carbide is slow. and 2) I really like having the gouges to show me where I need to work. The carbide wheels leave no scratches and if I've done my job well, I'll not see many facets when I move onto the 400 grit lap. Well, it isn't entirely true that the carbide wheels leave no scratches. They leave scratches that you won't see until the 600, or more often, 1800 grit step.
I don't enjoy repeating steps that I thought done.
Also re-remembered tonight that agates really like a round with tripoli after the 1800 grit diamond. Maybe put a pic up if I'm not too lazy tomorrow.
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Alright this is much later than "tomorrow" but I like this stone a bit more than the one I had in mind.
Wish I put a few more lamps in place. There is some very nice depth to that stone. Filled with black and white shapes swimming around and mixing with a semitransparent coffee colored chalcedony.
I like how my hand as well as the camera shows up in the stone's gloss. As well as the ridges of the paper towel light filters on my photo box.
Really should have gotten more light on it.
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