[maldridge]

Hello all! I'm new to the forum and I have to admit, I'm mildly overwhelmed at the number of forums, so my apologies if this is in the wrong section.

My girlfriend loves two things (other than me); NYC and vinyl records. My goal is to make a clock face out of an old record (most likely an extra Sinatra I have lying around) with the NYC skyline silhouette. The top of the record would be cut out to leave the silhouette. I'm in the process of tracing the skyline onto a 12" diameter circle on AutoCAD, but this is time consuming and I feel there must be an easier way to go about this.

Basically, I'm looking to CNC the record, seeing as laser cutting would produce chlorine gas and damage the cutter. I plan on using a lower rpm and feed rate when using the CNC as well as a very small mill, but I have no clue how I can program this skyline into the part. If there is a program that could help with creating the g-code, it would be much appreciated. For reference I've included the image I am using for the skyline and another to get an idea of what it will look like when complete.

[awerby]

Why don't you just trace the line onto the record itself, and use a jeweler's saw to cut it? Here's an example: German Jewelers Adjustable Saw Frame

If you've got a CNC machine, though, that's big enough, all you need is a CAM program to translate the DXF file into a toolpath. Since all you need is a 2D toolpath, one of these free programs should be sufficient: Free CAM Software Just find one that will accept a DXF file as input.

[maldridge]

Thank you for the help! I ended up using CamBam to generate to g-code. Now all I have to do is figure out how to program my part zero into that from the CNC so that it cuts in the proper place on the record.

[aarggh]

Just zero from the center of the record, so it balances either side. You'll need to maybe go over it twice, the second time allowing a fraction of an allowance towards the center, as I suspect when you machine it, you'll end with raised jagged edges. A second pass taking the closest of shaves off, or using a compressor blowing air onto the cutter path will fix that.

cheers, Ian