What do you really get for a $350 desk top engraver ?

i remember that movie and the part you are referring to lets hope my acorns are not that problematic and i find a use for them before i end up frozen in a block of ice

this is a tool path simulation screen shot with fusion 360. just to give some perspective of how small these features are the depth of this undercut section is only .03 deep and the design in the undercut section is only ,015 in height and the radius on these features is only around .008. i see some small sections that are to small to get into but for the sizes i am working with i would say it's getting pretty darn close to 100%

 

All in all i was happy with what the machine could do. looking at a picture of a small tool and holding one in your hands is two different things  

one thing i did notice with this machine is that surface finish drops on the more complex cutting moves on say a angle cut or circular cut. i have been trying to pinpoint the cause of this but i am still looking, it's not horrible but it could be better. my first thought was machine resolution or belt tension, i tried a finer resolution which might have helped a tiny bit and did some tweaking on the X axis to get the belt tighter to try that today to see if that is the problem?
at first i thought it might have been a rigidity related issue but after playing around with finished passes quite a bit i ruled that out after noticing the straight cuts were really good. i would think a tandem axis is going to be more rigid with 2 bels and motors opposed to the X axis with a single belt and motor. i think tests have proved this for me. i can actually get a .06 stepover around ,5 deep with the side of the cutter on the Y axis but get into problems if i get that aggressive with a cut on the X axis.

one other observation is the closed loop steppers being a huge benefit to having something work well in the end. i would also say over sized motors are good way to go too. food for thought Tommy if you build one   

I tend to do oversized everything, my Plasma machines can do 55 to 68 meters per minute but limited to 18-24M/M, 16 and 20mm round supported rails on the gantry and 30mm round supported rails on Y, etc.
The only things i still can not find here in the sizes i would like are cables and belts.

if i were to do it over again i would have doubled the size of the motor on the X axis in relationship to the size of the Y motors. i skimped on the power supplies and should have spent a little more for 48V rather than 36V too. wider belts might not have been a bad idea as well as long as sharp bends don't kill the life as a result.

this was a R & D type project for me and i had no idea what to expect but i'm happy to pass along my finings. the machine does well for what it is and i am just nit picking on little stuff. But regardless i tiny machine like this could be a time saver for you i think.