Pete.
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- Kent, UK
Big well done to Spencer he's borrowed my gear to work on his 1m square plate. Initial measurements showed that it was in very poor condition equivalent to perhaps grade 4. After several turns of grinding with my larger lapping plate he's turned out a very nice grade 0 surface.
Start of lapping - surface is a mess as you can see the dark patches are low spots.
Progress:
Lapping done, time to measure:
Here are the numbers. Each number is microns, in height above the lowest point. Max height defines the grade of the plate. The other notable figures are 'closure'. This is the software's checking method to validate the quality of the measurement. It's supposed to be within 2.5um or 25% max height, Spencer's clsing figures are well within both of those which means the measurements are very good. The plate is 1000mm square and the 6.46um max height puts it in grade "0"
Here's the 3d graph. The heights are exaggerated remember from lowest to highest is just 0.0064mm. With very little work this could be a "00" plate. A bit og grinding on the G corner, and lapping the line from A to C so that A comes down and C stays where is is would put it into "00" grade for flatness.
Well done mate
Start of lapping - surface is a mess as you can see the dark patches are low spots.
Progress:
Lapping done, time to measure:
Here are the numbers. Each number is microns, in height above the lowest point. Max height defines the grade of the plate. The other notable figures are 'closure'. This is the software's checking method to validate the quality of the measurement. It's supposed to be within 2.5um or 25% max height, Spencer's clsing figures are well within both of those which means the measurements are very good. The plate is 1000mm square and the 6.46um max height puts it in grade "0"
Here's the 3d graph. The heights are exaggerated remember from lowest to highest is just 0.0064mm. With very little work this could be a "00" plate. A bit og grinding on the G corner, and lapping the line from A to C so that A comes down and C stays where is is would put it into "00" grade for flatness.
Well done mate
