Surface Plate Resurfacing

[dwall174]

I just picked up a 24" X 18" cast-iron surface plate off of FB Marketplace that's in fairly good condition, but it will need some cleaning up.
There's your typical light surface rust on it that should clean up with some Scotch-Brite pads on my jitterbug pad sander.

Just curious if anyone here may know roughly what it would cost to have a 24" X 18" surface plate blanchard ground?

 

[Nutfarmer]

Even if ground , wouldn’t it have to be scraped in also? Just asking.

 

[extropic]

I can't tell from the pictures. Was the plate preciously scraped?
It may be a well worn layout plate (ground, not scraped) rather than a surface plate.
To answer your original question, I don't know what Blanchard grinding would cost nor, more importantly, how flat it would be after BG.

 

[dwall174]

Yeah, probably if it was going to be used for precision work.

I'm just going to be using it in my home garage for general layout work like marking hole locations on parts.

 

[dwall174]

Was the plate preciously scraped

I believe so.
Here's a picture of the surface plate from the original owner after he cleaned it up a while back.

The original owner stated that he hasn't used it in over a year, so that's why he sold it.

 

[FOMOGO]

I'd clean it up and check it out. I bet it's pretty flat having been scraped in, and for your purposes should be fine. Mike

 

[Ulma Doctor]

Please don’t use a jitterbug sander on your surface plate, you’ll do more damage than good if you’re going to use it as a reference surface.
You’ll need to scrape it in to regain a precise surface , but,
You’re going to need a precision reference to make your surface plate a precision reference .

You may wish to purchase a sufficient granite plate for use as your reference, to scrape in the cast iron plate, but you are always free to do what you see fit

 

[dwall174]

I'd clean it up and check it out.

I plan on doing that this weekend!

for your purposes should be fine.

Yeah, Your probably right!
Basically, I plan on using it to layout hole locations on parts like mounting plates & brackets that will be drilled out on my drill press.

 

[dwall174]

Please don’t use a jitterbug sander on your surface plate, you’ll do more damage than good

I wasn't going to be using sandpaper on the jitterbug, just some fine Scotch-Brite pads & WD-40 to clean up the surface rust.

You’ll need to scrape it in to regain a precise surface

I'm not really looking for that high of precision with this surface plate/ layout plate.

 

[extropic]

It looks like it was precision scraped, based on the full coverage of the markings. ScotchBrite (except White) is abrasive so apply it uniformly all over the surface. After cleaning, I would use a fine diamond lap, or equivalent, to search out high spots resulting from any dings,