Forums Beginner Questions Table cutting

21 replies, 9 voices Last updated by tucsonbear 4 years, 2 months ago
Viewing 7 posts - 16 through 22 (of 22 total)
  • Author
    Posts
  • #2707

    scottwkelley
    Participant
    @scottwkelley

    Thank you so much. So far my machine has been accurate as far as I can tell. The left to right is good. After using the marker I found sweeping the lap brought in the top and bottom evenly and also helped me with a better polish. I hope I never find myself having to use the cheat but I understand better now that it will be for the left to right mis aligned. Taking the time to make sure everything is true before the first cut is as important as the CP being perfect.
    My facets are improving and my meets are coming in true and with better precision. Loving it.

    #2725

    scottwkelley
    Participant
    @scottwkelley

    Hello all,
    Well the table cutting is improving and I have another question and this stone is teaching me something.
    The cut is Kristine Apex a antique square cushion. When I got to the table I laughed and did not believe what it said. 5 degree’s. What? The reason I laughed is because of all the angle setting to the 100th. I rounded off and called it good. Like making it 47 degrees.
    Well this is what I experienced when cutting this table. I found that I had to almost round the table by cheating the front to back to meet the points while not moving the right to left at all. I believe the 5 degree is meaning to center the middle of the table to allow the 5 degree to the front and negative 5 degree to the rear/back. When I did this the meets came in with little to no frustrations.
    Is this a good example of cheating but purposely having to be done?

    #2728

    Alan Balmer
    Keymaster
    @alanbalmer

    There’s a reason this was a Master’s stone 🙂

    Sounds like you did good. As long as you make the meets, there’s no shame in using the cheater or making minor adjustments to the angle, which is what you’re calling cheating front to back.

    This is what’s called an “apex crown”, by the way. It’s not really a table. Angles that low can be very tricky to cut.

    Some years ago Glenn Klein waged a campaign to eliminate the words “cheater” and “cheating”. You might find this interesting:
    Get Rid of Cheater

    #3277

    gemmakermz
    Participant
    @gemmakermz

    i see many answers all very good, yes you have to use those cheaters, everyone does i have found when cutting and polishing a lot of people do so swinging the stone from center to side. if you make sure your head and mast is aimed straight to the center of the cutting wheel and finish you cuts straight at the center of the lap you rill have less to cheat. a lot of the laps are a bit higher in center than on the edge even though their machine to not be, this causes an anglure cut on my ultra tec is rare that i have to cheat the table. mike zinski

    #3405

    scottwkelley
    Participant
    @scottwkelley

    Thank you for the help. I figured it out and feel silly. But after going back and reading Jim Perkins manual he talks at the end of fixing stuff. What I was not doing was taking the table down far enough to meet the last facet running through the top crown facet, then going back and bringing in the meets. After doing that things are getting a whole lot better and the crowns are looking magnificent to me now. As a student I find these problem solving issues to be a draw for me to figure out and master.

    Attachments:
    You must be logged in to view attached files.
    #3421

    tucsonbear
    Participant
    @Tucsonbear

    You guys are making me feel ancient. I bought a Graves Mark IV back in 1980, and I’m still using it. It’s modified into a nice bench top with a washing machine motor. For years now, I’ve been wanting to get the 1/10° angle mod, but as it means sending my head back to Graves for probably a couple weeks, I manage to keep putting it off. The cheater is pretty straightforward, and I can eyeball the angles close enough. Learn to “cut a little, and look a lot”, and you can head problems off before they become headaches. I’m deaf now, so I don’t bother listening, but learn to get the feel of the quill when cutting. Learn to use your height adjustment to make your meets, and you don’t need a dial indicator. Use your eyes, and learn your adjustments!
    Most problems with tables are caused by under or over cutting the girdle or star facets, use your eyes to make these as perfect as possible before you get to the table.

    #3422

    tucsonbear
    Participant
    @Tucsonbear

    P.S. back in the day, they used to cut fairly decent stones with a jamb peg. Cheating was easier then!

Viewing 7 posts - 16 through 22 (of 22 total)
  • You must be logged in to reply to this topic.