Help please. Dip switches and mach 3 settings

[Radu_Andrei]

Hi. Long time no see.
I.ve only managed to work a couple of days with the cnc in the last 3 weeks, and tested endmill, ballmills, speed, feeds, hardwood, softwood, with and against the grain and so on.
I.m mesmerized by it. :) A lot of fun and a lot to learn. In the end I fould the speed limit for x at 118ipm, and for y at 86ipm. (not bad for a 220 pounds gantry). They can go a bit faster, but I do not like the sound. It.s a bit low with a 17-18000rpm spindle (can.t go lower for long as it is air cooled). Still it seems to be enough to avoid heat or burns. Keeping the stepdown to apx 60% percent of tool diameter seems to work like a charm with all woods.

I bought a pack of stl files from ebay, and they seem great for most decorative jobs, except frames. There are lots of projects which have the frames included in the whole relief, and even if I.m not a fan of it, it looks fine in the end, BUT I also got a few frame designs on their own, and they do not have any joints. I guess it.s fine for mdf, but for solid wood, I wood very much prefer to cut 4 different parts from one piece of wood, alligned one next to another and also cut the 45 angles for each segment.

Reading a bit about this issue online, I found Autodesh Meshmixer (free) and gave it a try. Does not seem very hard to learn, but still need to study a bit.

But as everything with this project, asking here seems to save A LOT!!! of time. So the question is: What software do you use for editing (modifying) STL files?

For example I attached 2 files, with a separate frame and a relief with a frame included. I would like to remove the included frame first, and then cut the separate frame in 4 mitered parts so i can join and attach later. Also because I want it from another type of wood. How would you do it?