Did you mean 36" by 72".??
Oops. Yes inches not feetDid you mean 36" by 72".??
Thanks John, I have also carved soap stone with a foredom and dremels with burrs. This will be done at 12000 rpm in a CNC spindle.. the carving runs for each slab will approach 12 hours... so never carved soapstone 12 hours non stop..ScottArt,
Besides doing woodworking, I also carve stone. I carve alabaster, soapstone and marble...the first two are semi-soft stone, whereas Marble and granite are very hard.
Plaster, as rayk2 points out, is very soft. I have specially hardened steel chisels and gouges for my stone work.
For plaster, you can easily use a standard woodworking chisel and/or gouge, since the plaster is soft. You can also buy rotary burrs that will work well to grind away at the plaster. I have a tool from Foredom Tools
( Foredom Electric Co. ), that has a motor , flex shaft and bits. But you can buy a flex shaft that will attach to a standard drill, where you can attach burrs to it. Just Google it...
Sounds like a pretty big piece to be working on, even if it is 3 ft x 6 ft...that's allot of carving and dust !!
Good luck
John
Thanks Ray, Yes the dust collector and masks will be on full time. Do you think carbide will stay sharp for a 12 hour run?Plaster is really gypsum (calcium sulfate dihydrate) and on the Mohs Hardness scale is pretty soft - slightly greater than talc. Dihydrate means there are two molecules of chemically bound water contained within the mineral. This means that the plaster does a pretty good job of minimizing heat since the chemically bound water tends to act like a heat sink.
United States Gypsum (USG) used to have a product called Rayite Machinable Media. Not sure if they still make the product but it was specifically made to be machined.
At a minimum use carbide cutters. It's the dust that can be annoying so hopefully you have a dust collection system.
I really don't know if the cutter will last 12 hours - it depends on all the typical machining factors - depth of cut, speed, heat generation etc. Stick486 is also correct in the a typical shop vac being used as a DC will probably not like bring on for 12 hours.
If it were me I would break the machining into segments that allow for the cooling of the machine components.
20 hours a day????? Dang HJ you need to take a break.I run my Ridgid vac sometimes for up to 20 hours a day, and it keeps on running. But I do have it hooked to a Dust Deputy.
ha ha, just got to thinking...With a long finish cut --- set it all up and go to bed.
Or if the cut will run late a nap on the sofa til it's done. And then set it right back up first thing in the morning.