"indexing" a part on the table to work on both sides?

[myxpykalix]

I'm thinking about trying to make a sign for a friends farm here and basically i want to take an odd shape frame make a circle in the middle put "Dogwood" on top of circle. Put "Hill" on bottom of circle. Then cut out center and insert a "litho" of a dogwood tree in circle. Then i wanted to put an outside ground lite behind it to lite it up (lite will be back far enough not to burn it). A couple questions. Has anyone done anything like this with corian with any good results? Would i somehow have to darken even more the dark regions to compensate for the brighter light? I think i can resolve the lighting isssue with a different type of light.
Also when i have an odd shape sign I wanted to cut the circle out of the center but i wanted to turn the sign over and rabbit out a recess around the circle to insert the corian like a round picture frame. How can i "index" the part on the table so that when i run the rabiting file it cuts exactly in the right place? thanks

[drodda]

The corian should work good for this. I would do a few tests for the contrast as viewed from your prefered distance from the sign? I.E from the street driving by or from walking by at night.

As far as the rabbit for the corian. I always cut the rabbit out first while the blank is still square and then i turn it over and place it back into the scraps used to align it the first time to get it exact. Then I cut the rest from the front and it seems to work great.

Hope this helps,

[scottcox]

I'll answer the second half to that. Drill at least 2 holes (say at 2,2 and 22,22 on a 24x24 project) in your table or jig, then in the back of your workpiece (at 22,2 and 2,22) as you do your rabbit. Insert dowels, flip it and you know exactly where you are to cut the front.

[phil_o]

I have made a number of mirrors and picture frames. If you set up your work with the 0,0 origin at the center of the workpiece you should be able to flip the work and accurately locate the rabbet cut.
I used the Shopbot to cut a large grid on the table. The grid lines are spaced at three inch intervals. I draw center lines on my workpiece and locate the center at any convenient grid intersection on the table, for example 15,9. Then it is simple to move the router to 15,9 and begin my cut from that point.