Forums Beginner Questions Trouble with laps?

  • Trouble with laps?

    Posted by Kensington on April 1, 2017 at 3:02 pm

    I’m attempting my first “solo” stone on all new equipment. I have brand new 260, 600, 1200 and 3000 diamond toppers from Kingsley North.

    My first attempt was a citrine. It seems all grits have really left deep scratches into the stone. I’ll probably have to end up re-cutting.

    On one of the larger flat facets, I went from a 600 to a 3000 just to see the results (since I’m going to re-cut). The 3000, which I assume would be my pre-polish, didn’t provide any polishing effect that I was expecting. In my instructional class, the instructor’s 1200 did a great pre-polishing job, it was probably well worn.

    Should all these laps and the cerium oxide Lightning Lap I have, be broken in with some scrap quartz before attempting a stone?

    Thanks in advance.

    Kensington replied 7 years, 1 month ago 4 Members · 5 Replies
  • 5 Replies
  • Alan Balmer

    April 1, 2017 at 3:59 pm

    It might help on the toppers, but I’d use a hard stone, like CZ or synthetic corundum, rather than quartz. Not too much, because the toppers will wear quickly. Personally, I wouldn’t use toppers for anything but roughing, and 3K metal bonded laps, in particular, have a reputation for causing problems.

    The Lightning Lap should not be broken in with anything other than normal polishing. Once you successfully get past prepolish, you’ll probably find it’s working fine. If you continue to have problems, Marsh is a helpful guy. Look for information on the website,, first, and contact them if you have more questions.

    • Kensington

      April 1, 2017 at 11:38 pm

      Thanks for the feedback Alan. I did test the CeO2 LL on a spot of the citrine and it did give a decent polish, but just glazed over the deep scratches. Sounds like that’s the least of my worries.

  • Mary Rafferty

    April 4, 2017 at 10:19 pm

    Your experience with the toppers sounds similar to what I found with two I ordered for our club’s machine. Discussed in another thread

  • gemmakermz

    June 7, 2017 at 9:42 pm

    hi i used to make the diamond laps in the 70’s and found, then and now, the 3000 grit is useless unless your working with maylee stones ( less than 25 points 1/4 ct. where you have small facets. i’ve been cutting since 1965 and still doing. i use what ever coarse wheel for the size of stone i’m cutting but use only a good 1200 grit for final shaping before going to polish. usually you really don’t have to break in cutting laps just don’t let their faces touch another face for cross contamination. not sure what polishing lap your using, i see all kinds of laps out there and some that people are having trouble using. i have for 40+ yrs used only a pure tin lap that we made at crystalite, if you can find an affordable one its recommended. does your machine have a variable speed?? too many times the polishing problem is too fast speed. its not letting the polishing agent to remain in contact to stone surface long enough. i have an ultra tec and a raytech and they have a variable speed. using a tin lap with a VERY slow speed and using 50,000 diamond powder i use an very low water drip, just enough to make a thin mud on the working area of the lap and not enough to cause the mud to be washed off. i find this usually polishes about everything. i’ve been useing my laps for yrs but dont score them like some people say to. the most scoring i’ve ever done is rubbed with fine steel scrubber lightly. mike zinski

  • Kensington

    June 13, 2017 at 3:31 pm

    Thanks for the comment Mike. I have a Facetron. I’ve completely avoided the 3000 grit topper (it is quite useless). I’m using a 600 & 1200 topper, with a pre-polish with a D-Lite 3000 mesh. Polishing has been good with Lighning Lap Cerium and Aluminum oxide toppers.

    I haven’t been brave enough to buy/use a metal lap with diamond powder yet.

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