Thread: what do you think of my surface plate

i pulled it out and had a look today it seems very rusty and in need of scraping although i am a novice so i would like to know what you guys think.
sorry for picture quality it is from my phone. first pic is the plate and the second is the spot in the middle.

Originally Posted by welder

i pulled it out and had a look today it seems very rusty and in need of scraping although i am a novice so i would like to know what you guys think.
sorry for picture quality it is from my phone. first pic is the plate and the second is the spot in the middle.

Yeah, it'll need to be touched up for sure. Is it simply a sheet of iron or does it have cast in webs under the surface?

Greg

It's webbed on the bottom. This may bea silly question but doestheplate used to touch it up needto be bigger than the plate as I can borrow one. From school but it's thesame size or slightly smaller

Brfore you judge this "book by its cover", clean it thoroughly with steel wool and kero or WD40 - not with sandpaper or a stone.
Once you get all the rust off, have a good look at it from a very low angle, holding a picture or newspaper behind it and see if it reflects evenly. You will be able to see where the ripples or dents are. If you can't see any obvious ones, it may be pretty good.
To rescrape it, you really need another one that you KNOW is flat and use that to blue from. As big or bigger than yours would be good, but if the diagonal of a smaller one is bigger than the longest side of yours, you can make do.
The alternative is to have it surface ground (I did ).

Joe

Thanks Joe I will try kero and steel wool. When you said surface ground I relized the tractor club I am a member of has a huge surface grinder I can use.

Hi Andre,

It's hard to tell from the pictures, but there don't appear to be any dents or dings, just light surface rust, and if you do what Joe suggested as far as clean up, and it looks to be in good condition, you are probably on a winner.

If the surface looks good, I wouldn't rush off and get it surface ground before checking if it's needed, by bluing it against a known good plate.

What size is it?

Regards
Ray

Hi welder,
You'll need a plate sooner or later. Even if the surface grinder is top nick and can make the plate "flat enough" it wont be much good for spotting(assuming thats what you want the plate for).

How did you get around that Joe?

Stuart

Hi Stuart,
Phil ground my old surface plate (you may recall seeing it at the scraping class).
I haven't done anything to it since. I've used it for spotting a few times and it works just fine as it is. As well as the ground angle plates we used for spotting the right angles on our cast iron blocks. The trick is really to use a thin coat of blue, since it doesn't "soak in" or run into any scraped dimples.

Joe

Thanks everyone. Ray the plate is 1 foot by 1 foot 18 inches. The plate doesn't have any dings in it.

Andre,

Another means of removing rust from a flat surface is to use a single edge razor blade. They do not abrade the surface thereby maintaining the accuracy. Good for rust on gauges, squares etc. I read about using razor bades to remove rust from old hand saw blades years ago and became a devotee.

BT

Originally Posted by welder

Thanks everyone. Ray the plate is 1 foot by 1 foot 18 inches. The plate doesn't have any dings in it.

So you mean its 12" x 30" or 1' x 2' 6".

oops it's 12 inches x 18 inches