Off Topic–How I Prepare Files for the CNC Plasma Cutter

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It’s a hobby that I don’t have much time for, but I usually find myself doing a project with Hubby’s shop equipment right around Christmas time. This year it’s a key-holder plaque.

I start with a concept. We’re in Minnesota and fishing is the deal. So I’m thinking a fish jumping out of the water. It takes several passes, but I finally get something I like. (it’s #3)

Hubby says you need a Walleye if you’re fishing in Minnesota.

Google images supplies the Walleye and some Water. I bring the images into Paint.NET (free download from here) And I use layers ( google search for tutorials here) to be able to arrange the pieces to my liking. I’m thinking I’d like to keep the water effect down through the key hooks too.

Now that I have an image that will work, I need to get it into vector format so that I can use the CNC plasma cutter (thank-you Darling Husband) to cut it out of sheet metal – that will be the canvas to be painted on.

I’ll trace that bitmap image from Paint.Net in another freely downloadable program: Inkscape (get it from here) AND – you can get this for the Mac too. (here’s a google search for tutorials on tracing in InkScape)

So, when I got this traced, I can save it from InkScape into a format that is supported by the CNC Plasma Cutter’s software for import – that is .dxf. I DELETE the bitmap, leaving only outline and save it as .dxf. ( tutorials for this too)

There are some few things to remember with the traced image. For example, holes for nails or any holes which will be cut out of the metal need to be cut out first, before the outline of your image. So when the holes are cut out there is a solid backing. This means the instructions for cutting them need to be at the beginning of the file (known as Z-Order). The way I accomplish this is simple. When I’m done I select the outline – cut it (Ctrl-X) to my clipboard. Then paste it back into it’s former position (Ctrl-V). Note: do this after the bitmap is removed ( all you’ll see is outline, no fill) that makes it easier to tell if you’ve selected the right object in the document to bring the ZOrder into line.

Making sure it’s sized properly – I use scrap metal for the blank sheet metal placement. And the stickers will be printed same size too.

I put my new .dxf file onto the data stick and head out to the shop. Have the CNC machine do it’s magic. GRIND off all the rough edges, Paint the sheet of metal. Then what I do for my prototype is print a sticker of the bitmap and stick it on. The clear coat for prototype is clear contact paper.

Here's the finished prototype– it will have to be hand painted. Good enough for proof of concept.

This is one of them finished - nice little keyholder beside the back door, maybe.

You can get one at Wild Prairie Creations. Or just go and check out some of my friends handmade creations there.