non-circular boring.. Literally - it is boring!

I decided to see if I could create a polygon shaped hole with a little math and a cnc..

 

And now in aluminum!

 

 

Edited By sam sokolik on 31/03/2020 04:16:05

Impressive Sam, now you should be able to make your own socket head cap screws.

Thor

Looks useful. I expect the maths is similar to what is used for single point turning of polygons on CNC lathes with the added complication of a rotating tool.

Martin C

That's excellent Sam, thanks for sharing. I'm just beginning to find out about CNC and it's fascinating what can be achieved.

Brian

I expanded on the work Andy did...

I also am working on the functionality of slaving the x axis to the radius of the polygon... SO you can do things like create a profile for the polygon to follow. So this is a radius into a taper..

That's interesting stuff you're doing, Sam.

Could you post some gcode here please, so I can try it with my PlanetCNC control, which is designed to be LinuxCNC compatible?

I'll get Alan at cncyourmyford to have a look too as I'm sure he'll be interested.

Martin.

This is a simple hal component that takes the spindle posltion from the encoder and calculates where the x/y axis need to be to keep the tool tip perpendicular to the polygon. (well - to the inscribed circle.) This is done in the real-time layer of linuxcnc. So 1000 times a second it reads the spindle postion and calculates the polygon shape. I use currently the digital/analog i/o functionality in gcode to communicate with the component. I think it could be converted to remap to make it more user friendly. I don't have the gcode here at the moment but I think this is the latest hal component.

**LINK**

A hex bolt head isn't exactly a standard.. but..

Nice !!

MichaelG.

Hmm...

Broach this! (the vertical lines are the encoder resolution...)

Comment rev.1

Very Very Nice !!

MichaelG.

Ok - I need to get a higher resolution encoder.. Then The surface finish will be better and I will be able to go slightly faster.... (I might have to bake in backlash comp too.... (x axis has a bit of backlash))

Phase 2 - Better spindle encoder..

Encoder seems to work better...

Comment rev.2

Even nicerer still

... I’m clean out of superlatives now

MichaelG.

I think I get a D for effort...