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lugnut
03-02-2007, 01:47 AM
OK, so after reading all the good things about the great buy on ENCO’s 12X18X3 surface plates, I ought one. It arrived today. I must say that an idiot packed it! The box was about 16” wide x20” long and 16” deep. The box was beat all to heck. The UPS guy who has become very friendly and accommodating, (meaning he is more than willing to help and make sure his service is acceptable) would not leave until he was sure that what ever was in that beat up box, and weighed 80 pounds was OK. I still can’t believe they can ship it for FREE so I really can’t compane too much can I?
Now, not knowing one thing about “surface stones”, how do I mount it? It’s going to have to stay on top of my shop table, which is a 1-½ inch thick butcher-block maple table. I have read where the best way to set them is on three legs or feet. My idea is to cut three 1 ½ inch diameter disks from 1 inch polyethylene (which I have a good supply of) and glue them to the bottom of the stone. This will keep it up off of the table so I might use clamps to hold something to the stone, and will also keep it from rocking. And most of all will let me get my fingers under it to lift it if needed. Am I missing something or need to do something different? All Ideas are welcome and needed.:confused:
Mel

SGW
03-02-2007, 06:26 AM
There are no feet already on it? Maybe that's one of the reasons the cost is so low...

There's a whole theory about locating the three feet to ensure minimum deflection of the stone. It's defined in some surface plate standard, which might conceivably be online somewhere -- I have no idea. If I get a chance, I'll measure the locations of the feet on my Starrett 12x18 plate and report back.

Evan
03-02-2007, 07:25 AM
Here is the info you need.

http://www.qcssindy.com/techpapers/surfplatesupport.htm

http://vts.bc.ca/pics/splatefeet.gif

SGW
03-02-2007, 08:21 AM
Good stuff, Evan -- that takes care of the general case.

FWIW, I have a 2-ledge surface plate, and going by the guidelines Evan posted the locations of the feet seem to be based on the larger, top dimension of the stone, not on the smaller dimension under the ledges.

Evan
03-02-2007, 09:43 AM
It isn't critical at all with small plates. Their stiffness is much higher in relation to their mass because of the cube/square ratio. The main thing is to use three feet to provide even support and the idea is that some of the mass overhangs the feet to compensate for sagging in between the feet.

With a plate that size you could also just plunk it on a piece of soft material such as a folded up towel and would never be able to measure a difference.

sch
03-02-2007, 10:32 AM
A friend has two 12x18 surface plates from ENCO, one with a 3"
chunk knocked off the corner in shipping, the other the replacement
with a "Keep the bad one" note sent with it. Packing surface plates
of any size over 12" is an art form not studied by ENCO and several
other lower priced tool companies. The things are shipped in by
container load and handled by forklifts enmass til sold when they
are plopped in a (usually) single thickness cardboard box with a few
peanuts and dumped in the UPS package damaging system. Even
a double thick cardboard box is not going to stand up to a loose 80#
hunk sliding around in a series of 3' drops on conveyor belts. When
the proper packing costs almost as much as the product that is what
you are going to get. It is also why #80 rotary tables and 6" vises
are sent motor freight by Enco instead of UPS though they are well
within the weight limits of UPS. Too much damage to more fragile
bits than (so far) surface plates.

Tin Falcon
03-02-2007, 11:10 AM
It isn't critical at all with small plates. Their stiffness is much higher in relation to their mass because of the cube/square ratio. The main thing is to use three feet to provide even support and the idea is that some of the mass overhangs the feet to compensate for sagging in between the feet.

With a plate that size you could also just plunk it on a piece of soft material such as a folded up towel and would never be able to measure a difference.
Mine is just sitting on a rug on top of a file cabinet. I do not usualy worry about tenths and use it mostly for layout. BTW I have a 12x 18 Grizzly surface plate.
Tin

Evan
03-02-2007, 11:23 AM
If you want to use feet I wouldn't use poly-anything but instead use natural rubber. Three hockey pucks should do nicely and you don't need to glue them to the plate. Just set the plate on them. It isn't going to scoot around.

Go to any decent sporting goods store and ask for goalie training pucks. They are smaller at 2.25" by 3/4" thick and cost maybe $1.50 each.