What Did You Buy Today?

[Inferno]

There are a bunch of things I need more, but I just couldn't pass this up. 24 x 24 x 8" Starrett grade A surface plate on a cart with a current calibration and not a mark on it anywhere. It was at a local auction just 25 minutes away and the majority of the stuff was less than five years old. I've seen surface plates locally, but more often than not they're too big or priced ridiculously....this was $300, so not a steal, but seemed fair.

Showing my ignorance, what's a surface plate good for?
I've had a typesetting stone so I know they had uses in the past.

 

[extropic]

Showing my ignorance, what's a surface plate good for?
I've had a typesetting stone so I know they had uses in the past.

Surface Plate wiki

 

[Inferno]

Surface Plate wiki

Yes, I understand their "function" but what do hobby machinists use them for that a decent marble slab can't be used?

 

[Inferno]

I got these.

I drill a lot of 5mm holes and these have worked well for me. I figured it was time to have more than one on hand.

 

[Jim F]

Yes, I understand their "function" but what do hobby machinists use them for that a decent marble slab can't be used?

For a home hobby shop marble works fine.

 

[extropic]

Yes, I understand their "function" but what do hobby machinists use them for that a decent marble slab can't be used?

I consider myself a hobby machinist and I use surface plates for exactly what is described in the wiki.
Real surface plates are not made of marble because it is a relatively soft stone and will ware much faster than granite or cast iron.

Is the flatness of the "marble slab" you refer to certified per ASME B89.3.7-2013?
If some marble slab meets someone's requirements for precision and durability, so be it.

 

[Inferno]

I consider myself a hobby machinist and I use surface plates for exactly what is described in the wiki.
Real surface plates are not made of marble because it is a relatively soft stone and will ware much faster than granite or cast iron.

Is the flatness of the "marble slab" you refer to certified per ASME B89.3.7-2013?
If some marble slab meets someone's requirements for precision and durability, so be it.

I don't make iso 9000 items so, no, my marble slab is not certified ASME B89.3.7.2013

 

[extropic]

I don't make iso 9000 items so, no, my marble slab is not certified ASME B89.3.7.2013

I apologize. My question regarding flatness certification was intended to be rhetorical.
I should have included some emojis.

 

[mmcmdl]

Not a new purchase , but found down in the other house . Couple of insert tools and indicators . Add em' to the pile !

 

[Buffalo21]

I ordered some better ER 20 And ER 32 fractional collets, but not from Toolots!!