[Gallen66]

Hello Everyone,

I'm new to this forum. I was on G+, but thrown out after they closed shop. I built my CNC about a year ago and I'm still trying to get the bugs worked out. My machine is a 3-axis (currently) machine with 4 stepper motors, made of 80/20 aluminum extrusion (profile 3030) and driven with ball screws on linear rails. I use an ESS motion controller connected to a PMDX-126 BOB with 4 DM542T stepper drivers and run Mach 4 controller software. Electronics are similar to those of CNC router parts (except for the drivers). I've been having issues with the movements shuddering and staggering during some movements which result in poor cutting. Here's a picture of my machine the results I got while trying to run the V-carve trial cut "Bullshead". I thought, initially, it could either be settings in Mach (i.e. look ahead lines, and exact stop vs Constant velocity mode) but I changed those settings and I still have the same result. If anyone here has some ideas, I'd love the assistance.

[Ntl]

Have you checked the machine for any mechanical problems like binding or undersized stepper motors? Also you should post a video of the machine cutting it would be easier for someone to see if it's something obvious. Also post what your tool path is, cutter size, feed rate, spindle speed and so on. It's really hard to say by looking at a couple pictures with not much other information to work with.

Thanks
Dan

[routalot]

One thing I learned about V-carving lettering is that you need to use a tool intended for engraving and which has a sharp point.An early attempt with a 45 degree tool had areas that resembled the most severely wrong image that was posted and it was because I touched off with the 2mm wide flat tip of the tool.I have since bought one or two engraving tools and that problem went away.

Before blaming excessive cutting depth and consequent machine flexing,can you give more information as indicated above and please include the software used to generate the toolpath.It may be that somebody can advise of a setting that needs adjusting. It could be something as fundamental as using a value for the angle of the tool tip that doesn't correspond to the actual shape.