Heavy, Pink and American. :D

[sc_rufctr]

I picked this up on Monday. I ordered it about 10 weeks ago.

It's a Starrett Crystal Pink granite surface plate (Grade B ~ EPD 80634, 24 by 18 inch)

Granite made somewhere on planet Earth but cut shaped and flattened in the USA... I couldn't be happier with the whole deal.

I priced a similar sized plate made by Mituyoto and it was about $300 more than this one! (Black Granite, cut shaped and flattened in Brazil)



Top of the shipping crate. Note the international compliance sticker for export.



And the accuracy certificate. (It's actually a bit better than what would normally be considered Grade A in flatness)



With my newly acquired Starrett height gauge. (US made)

[trekkor]

What's it for?


KT

[look 171]

I am no machinist, but why granite and not cast iron or steel of some type for this application. Cast iron has a tendency to warp even if it thick like 3-4"? Do the type of granite matter, I know some are harder then others depend on the grain and texture they expand and contract just like anything else.

[sc_rufctr]

According to my own research Crystal pink Granite has the highest Quartz content of any granite so it hardest wearing.
Mitutoyo surface plates are made from Black Granite.

I was looking at a cast iron plate but these rust but can be hand scrapped when needed.

Granite is the preferred choice for a lot of reasons. For instance if you damage the surface it won't mushroom up like an iron plate.

Originally Posted by trekkor

What's it for?


KT

For measuring just about anything very accurately but it also has many other uses like scribing accurate lines in sheet metal.
Tool setting and it's invaluable for copying something for prototyping.
Also with the right scriber you can use it to scratch ceramic or porcelain tiles ready for snapping.

[Jon B]

Originally Posted by sc_rufctr

Granite made somewhere on planet Earth but cut shaped and flattened in the USA... I priced a similar sized plate made by Mituyoto and it was about $300 more than this one! (Black Granite, cut shaped and flattened in Brazil)

Starrett used to mine their own pink granite from a quarry in North Carolina, but I don't know if that's still true.

Yes, pink granite is more durable than black, with a high percentage of crystalline quartz. Very nice, Peter! You need to build a proper stand for it, to support and level it, isolate it from vibrations. What are you tooling up for?

[sc_rufctr]

Jon

I make things ... from customs tools to thermostat housings. I have a long to do list.
I also service and repair vintage cameras, mostly Leica range finders but I recently rebuilt a Pentax from the early 80s.
Sometime I have to make parts because a lot of stuff is NLA... Film usage is still strong in my town.

I'm designing a stand right now... 100% Aussie made steel with levelling feet and an additional storage shelf at the bottom.
I did consider a bigger plate but that would have been extravagant considering the stuff I make.

[Jon B]

Originally Posted by sc_rufctr

I did consider a bigger plate...

How about this one...

[sc_rufctr]

Thanks Jon but that plate wouldn't fit in my little work shop.

Another shot of the crate. Made from what looks like construction lumber certified to be pest/insect free... For customs purposes.

[Tim Hancock]

Hmmm, I have two granite plates that are only about 3" thick that a friend gave me when cleaning out his shop.... I guess they must be worth something.

[wdfifteen]

I love stuff like this. I have a 12x18 black granite surface plate that I've never used. It's just cool to have around.

[lane912]

this could also be used to seismically isolate stereo equipment-
think about holding a transformer perfectly still and how it would work better than shaking it-

[herr_oberst]

Lots of people put their stereo turntables on surface plates.