Need help radiusing a surface

[tim_mcknight]

I would like to take a 3" wide x 20" long x 5/16" thick board and cut a constant 16" raidus the entire length of the top of the board when viewed from the 3" end view. The radius is measured in the 3" direction. I can't figure out how to draw this. Can anyone help? I briefly spoke with Bill Columbo at a "camp" and he said to use the extrude command? Can this be drawn and designed in Part Works or does this have to be drawn in CAD first? I am a NOOBIE so please keep that in mind when responding. Thanks...

[jporter]

Tim, if I am reading this right, first bring up PartWorks and put in your material size and thickness. Then switch to the drawing board and pull down a guide line to the 16" level from the top of your material,(X axis) even if it is out side the material. (May be a negative number). Then bring over a guide line (Y axis) to middle of your material. Where the two cross should be the center of your 16" radius circle. Then go to the "circle" symbol on the drawing board and set the rad for 16 and hit the draw button. This will give you a circle somewhere on the drawing board. Then use the "select" arrow and hi-lite the circle and it will turn red and then select the "move" button and move your circle to where the two guide lines cross and you should have an arc with a 16" radius across the top of your material. Then you will have to hi-lite the circle and select the "node edit" button and "insert a point" and then "cut the vector" at each side of the material where the circle passes the sides of the material. Then hi-lite the unused part of the circle in the "select mode" and hit the "delete" button. You should end up with a rectangle with a vector across the top in the shape of an arc and you can go to the cutting side and pick the "profile" function for that vector and that should do it. Be sure to preview this and see if it works. I hope this helps, joe

[knight_toolworks]

you don't even need the guides. all you have to adjust is the height of the cut. centering will do the rest.
also make the ends hang over by the length if the bits diameter so you get a smooth start and finish.