that's any half-decent fabrication shop!
and they're EXPESNIVE to get resurfaced if you wear them down!!!!!
we use granite because it doesnt tend to warp or change shape much (HOPEFULLY)!!!
but those things are FLAT to within just a few millionths of an inch per foot, usually.
but also its funny that it doesnt matter if the object is a 2 inch plate or a 10 foot frame. all will be judged by the slab.
the head from your shitty lawn mower that you just decked by eye on the shittiest mill with a pretty dull fly cutter????
TO. THE. SLAB.
If you'd like to know more about taking care of the your very expensive surface plate SLAB that every machine shop needs, here's Adam Booth:
a grade A slab can have a total flatness of 1/10th of 1/1000th of an inch. which for reference, is about 30x smaller than a human hair. they give you a slab certificate that details how flat your slab really is after they are done making the slab.
the bottom of the slab has three points that it rests on. these points were set at the factory before the slab was flattened, and these points should not be moved.
setting down your drink or your keys or whatever on the slab is like driving your car through a preschool building during business hours. the slab is for checking flatness, not recreational activities.
dust itself can change how flat the slab is. keep the slab covered when not in use. keep rugs or mats or something around the slab to help reduce dust being kicked up from walking around.
clean your slab before use to make sure it is flat. do not use water to clean the slab. water can soak into the slab and change how flat it is. isopropyl alcohol can work.
anything that gets put on the slab must be put on the slab with the delicate touch of an angel. do not injure the slab.
so yeah i think sex is forbidden on a grade A slab. maybe you can do that on grade B because that shit gets metal shavings all over it.
