Author Topic: Fixture plate repair  (Read 1705 times)

Online steamer

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Fixture plate repair
« on: August 14, 2012, 09:54:17 AM »
Got this 3 sides plate on the "Bay" a while back.   PRECISION GROUND was stated.....seems I've read that before

It really wasn't too bad....but someone had gotten happy with a slip stone as is the case



You will notice the left and right edges are not marked up?   That's probably from the previous owner stoning the block.  The corners go down first as the corners collect the most dings....you have to be really careful with a mark up like this as it may be crowned...high in the middle.   If that happens the mark up will be unstable and mover around....and you can chase your tail trying to get it flat for hours.

To get around this...I started the process by taking the middle only down.   By doing this the bearing area gets drastically reduced and now it will bear on two distinct areas...left and right.   Why do this you ask?   Because the bearing will now be stable and it's a simple matter from there to bring the whole surface down slowly until the whole surface carries.

In the next picture...it appears the marking has carried...but the center area is a little "LIGHTER" than the left and right edges...we're talking less than .0001"....but the plate is stable....and I suspect I'll stone the little bugger a bit as well.......




I didn't take pictures of the next step which was to get the ends square to the large face.   I'll see if I can set that back up and show how to use an indicator stand as a gage to check squareness.  Probably this weekend coming though.....

Dave
"Mister M'Andrew, don't you think steam spoils romance at sea?"
Damned ijjit!