My local engineers where I've had a few pieces laser cut were quite happy with sketchup files, they imported them into their Autocad program no problem but they prefer Autocad files when the designs are quite complicated, if you intend having some CNC work done by an engineering shop I would ask them what formats they prefer before buying a CAD program.
I've always used AutoCAD to produce files for laser cutting. Are you a student by any chance? Autodesk have their full catalogue of software packages available for free for students.
Video link Just be aware that SketchUp doesn't draw circles as circles, it draws them as a circular segmented polyline.
I'd say you need software that can export to .dxf, as it's the closest thing to industry standard in CAD software. I know SketchUp can be exported to either .dxf or .dwg, can't remember which off the top of my head, but I think there are issues with how it handles curves. When I've exported from SketchUp into AutoCAD in the past, the curves end up being made-up from a series of straight lines, whereas native curves in AutoCAD are proper curves. I think this can cause issues when it comes to CADCAM because instead of a curve being a single line, it'll be made up of hundreds, if not thousands of small lines. This is of course very inefficient and will at best slow things down, at worst I suppose it could result in jagged curves if the segments are too big, or cause other issues if there ends up being tens of thousands of separate lines for the CNC to cut out. Maybe there's a way to export from SketchUp which alleviates this, or maybe there's another free/cheap piece of software which handles such things better, I'm unsure. I've never needed to look as I've always got AutoCAD installed.
The correct answer here is that any CNC specialist should be able to accept CAD drawings from any one of a number of industry standard applications including AutoCAD, SolidWorks, SolidEdge and even PTC Pro/Engineer (now Creo Elements/Pro). The actual answer is that you'll have to contact the machinist to see what format they can accept drawings and models in to create tool paths for their machines. I have designed and modeled in all of the above now, and SolidEdge is the one I keep going back to. Any water jetting, CNC milling, CNC lathing or laser cutting I've had done in the past few years from three different companies was modeled in SolidWorks and sent to them as a .PAR file. The only exception to this was when I had a prototype part manufactured from a SolidEdge model when I was still at university. As far as I know (speaking from very little "on the factory floor" CAM experience) from any file type they are able to create the tool path required for their individual CAM based machine in CAM software, or if it's an older machine in the case of the CNC lathes at my local turning plant, generate the required G-code to feed into it. I don't think any of the applications I listed are incompatible with any industry standard CAM software, so you have a lot of choices. I know you've mentioned that you're modeling something in SketchUp and what I'm about to say is practically blasphemy around here, but I installed it once long before I learned to use any other application and only ever designed one PC side panel in it (which never got manufactured ) before installing Pro/Engineer which I was introduced to at school during a course ran by a visiting college lecturer. I picked up anything I know about AutoCAD whilst working for a commercial refrigeration company one summer, was taught Solid Edge at university and went to a night class to learn SolidWorks somewhere in between. In any of those places I mentioned, when asking about SketchUp, I was advised to stick to the industry standard professional software because it was more easily worked with by anyone and everyone when it came time to get any sort of machining done. I know that doesn't help you much now though, sorry Is it a particularly tricky part? I wonder if I could model it in SW for you or even convert it from a SketchUp document to SolidWorks?
