Quick Chips: Restoring a sine plate, Part 9
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- เผยแพร่เมื่อ 2 มี.ค. 2024
- In which we are armed with backlash compensation, a properly dressed wheel, careful measurements, and a sense of humor. We nail down the critical dimension we were chasing, and put this part to bed. At least for functional ground surfaces.
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Nicely done. Sensei.
Hi Spencer, nailed it.
Kinetic Precision is the name and precisions the game....
Regards Kevin
enjoyed….success 🎉
Outstanding Sir. I'm still learning, and never really thought of using incremental on my micrometer. I'm still so used to storing the data on my Ti-83 when I do the math.
HUGE Win
👍
This series is super interesting for anyone who does anything with surface grinding. this inspired me to check the backlash of my J&S, knowing that it is equipped with linear scales to compensate for backlash, among other things.th-cam.com/video/-zDKMdv1C0U/w-d-xo.htmlsi=mcShgTUFpN0pfwAK
Thank you, sir!! 👊
@@KPNH i assumed your Okomoto has no linear scales? Am i right about that? How do they achieve the accuracy? By ballscrews? Regards Antoine (The Netherlands)
@tantancnc Yes, ballscrews on Z and Y.
Your joe block stack up looked shakey at best. For that kind of mesurment two sets of blocks should be used. Not a good idea to just add a block on top of another. Such a nice grinder should be complamented with a nice square set that you can bolt together.
You betcha'!!
Believe me I fully understand trying to get something as close to exact as possible. I'm cursed with that perfection and accuracy fixation myself. But just to put this project into a real world perspective. Depending on the steel alloy, it's generally accepted in round numbers that steel expands or shrinks at roughly 6.5 millionths per inch / per degree. So for just the 5" roll spacing on that sine bar, your looking at around an expansion or contraction rate of that 5" of roughly 32.5 millionths variation with every single degree it increases or decreases in temperature. There is something to be said for having confidence in your almost exact 5" spacing at least within it's usable accuracy level though.
But unless your shop is set up about like Moore Tools illustrated in there Foundations of Mechanical accuracy book for almost perfect and stable temperature control, your way past what can be reliably used or even measured with any real certainty with the metrology equipment your showing. Then there's the same thermal changes in the gauge block stack etc. And the gauge blocks themselves aren't even 100% stable just due to changes over time even if there never used. Mitutoyo advised me that for steel gauge blocks, it's possible to see up to 1 Um of length change per inch up or down over any one year period. I am still impressed with what you managed. But as constructive criticism, in my opinion the whole series was drawn out much too far. Maybe extend the video length a bit, edit a bit more for the less important, and down to one or two videos.
Thanks for taking the time to communicate all that!