Corain S shaped counter top

[toddmaci]

I have a cabinet shop customer looking to cut a corian “S” shaped counter top. He wants a template cut for the top layer. I plan to cut the 2 build up layers on the bot. I drew half the table in Part Works then offset inward by 2.5 inches, then mirrored it. What is the best way to segment the build up area around the edge so I can cut individual pieces. Customer suggested making the segment pieces .125 long ( on both ends) and he would cut to fit. His thinking is if I cut to size there will be a compounded error with glue taking up the space between the pieces so he will cut to fit. Any suggestions on technique would be appreciated.

Thanks,

Todd

[Gary Campbell]

Todd...
I have done this a number of times for marine countertops. I havent seen enough of your mentioned coumpound error to justify adding an eighth to each piece. In most cases, a swipe with a sanding block will remove enough material to allow for glue. Cut the top exact and let him use the top as a template for the edge buildup.

I think your customer, as a non cnc owner, is suffering from a lack of confidence in your machine. He is asking you to perform uneeded operations, adding to your (his) cost. If you add 1/8 to the segments you add to his labor time and cost. Your machine will cut easily to .015" tolerance. Half of the smallest mark on his tape. If he needs it closer than that, tell him to have NASA fax over the digitized drawings.

As you might tell, I suffer no lack of confidence in my machine or my ability to have it do its job. Puff up your chest, grab a cup of confidence, cut him a couple samples and show him you can do the job right.

[toddmaci]

Gary,
Thanks for the response. I do have a sample piece of material to work with. Any suggestions on bit and feed rate.Two passes? I have a 5HP spindle with 2 fein vac hold down and your low profile piping system.

Thanks,

Todd

[Gary Campbell]

I have cut Corian with Single O flutes from Belin, Onsrud and Centurion. All were good, never got the chance to put them against each other. On cutouts that are going to be sanded and routed I have used a 2 pass, conventional 2ips 12K rpm strategy. On Inlays and inside holes, same speeds, but a .020 offset full depth conventional pass and a full depth cleanup to remove the offset.

Play with your move speed to eliminate any chatter from the bit.

[bleeth]

Like Gary I don't believe in cutting buildup parts with "extra" material. I do curved tops on a regular basis and do a lot of the buildups only 1/2" wide if they are not going to get a full bullnose. For a strategy I use straight 1/4" O-flute, cut 1.5ips and turn the spindle at 12K. I stopped using an offset, particularly for small parts, and just do it in 2 or 3 passes (depends on the size of the parts) with the last pass being a skin pass (.06).
Note: a wider buildup is safer. I do lose one occassionaly but there is usually material on the sheet to cut another since nesting a bunch of curved parts tends to waste space anyway.
The first time you cut Corian it's a bit nerve wracking but when you see how easy it machines you get over it quick.

[toddmaci]

Thanks Gary and Dave.