This is a project with the Hobby CarveWright little CNC and working within the limitations of a sled system. The concept of a "Peek-a-Boo" board could come in handy with a traditional CNC if the Standard methods didin't work.
I thought this idea of a "Peek-a-Boo" board could be useful if someone needed to line up a engraving plate a 2nd time if standard methods didn't work. In my case with my CarveWright using a Carrier Sled I needed to place a item back on the sled and cut through the first holes... Here is how I did it...
I am working on this big Accountability Board project and in a rush to get the prototype done and submitted I did not think through all the steps and planned to make some up as I went along... It is a sheet of plastic that has 40 slots cut into it then printed. After printing I epoxy a red edge guard around the plastic. Then I was planning to use another sled and index off the edges and cut the slots again in the red guide over the first holes... What I did not plan for is slight differences in the process of hand corner notching the edge guide and the variable thickness of epoxy... So I could not index off the edges...
That got me thinking of other options and I came up with the "Peek-a-Boo" sled.... So I made a sled slightly bigger than my Accountability Board with Hardboard and some 1.5 x .75 strip stock. I used epoxy to hold the strips no nails. I moved my artwork away from the rails slightly and saved it under a new name. I put a blank sheet of plastic or FRP that I use for the Boards and Tags and cut the 40 slots and 2 access holes and made sure the sheet was bumped up against the top of the designer screen and the far right.
I then placed a Accountability Board in the sled and laid the "Peek-a-Boo" sheet on top... With the top sheet indexed on the top and right I moved the bottom Accountability Board playing "Peek-a-Boo" with the holes in the first one... Once I got it, I pressed it down through the big slots and slipped some blue painters tape along the top of the rails and Accountability Board locking it in place. For the slots I told the machine I had a 3/8 inch bit installed but used the 1/8th inch cutting bit. That locks the feed rate into 1st gear for all the holes. I set the depth to .7 to give the bit a chance to go around a few times cleaning out the hole. The Accountability Board rests on about a 1/2 inch of scrap stock. I use PLACE ON END or in my case CORNER and you get the SAME Result EVERY TIME....
This lets me have "Repeatability" and I can now cut the other 79 boards.... Next batch I will set up the Art to print on a blank board with no holes and cut the slots after adding the Red edge guide. I will use the same "Peek-a-Boo" board but just use the bigger open areas and line up on the lines of the printed artwork adding a index mark on the Peek-a-Boo" board.
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