Fourth axis on router

[simso]

Okay, well after much dilly dallying and revisions, its finally done and fitted. Had to wait for some new couplings which arrived today "yay"

My first version was super smooth, roller bearings, laser cut parts direct mounting of motor etc, but becuase it was so smooth and easy to turn it actually chattered a bit in use. Also the direct mounting was no good becuase there was no ridgity.

This time I used a rotary table that has a 90 to one ratio, so it meant one turn of the input shaft and the rotary table turns 4 degrees, my stepper turns 1600 times per external revolution, so it was rigged as 400 steps = 1 degree of movement "compared to version 1 4 steps = 1 degree", so now it has ridgity to the gazoo.

Ive still got to do up a simple first program run cut, maybe just some dowel with some spiral writing around it, but currently it works perfect manually commanding it

[rodm]

Nice work Steve.
Greg posted a link to a program called Wrapper which converts linear to angular or the other way around. Anyway it works so hunt that one down.

[simso]

Well for those that are contemplating an a axis, heres some pre warning for you,

The first hickup I have is the z axis doesnt clear high enough with a cutter in the router, it needs to be able to go higher to clear the 200mm chuck fitted.

For me to fix this, I had to strip down my Z axis. Cut 2inches of my ballscrew and 2 inches of my z sled and then re-assemble, took about 2 hours of stripping and lathe work to get it going again.

Okay next hickup was I wrote up a simple g code facing program and ran it, after running the program my piece of wood was 30.2 mm on one end and 29.7mm at the other end 150mm away. So this means the a axis needs to be fine adjusted and shimmed to obtain a dead accurate axis in realtion to x and z.

So all shimmed adjusted run a few times and wolla 26.85mm on one end and 26.85mm on the other end

So this has now re-interated to me, that if you are going to setup and fit an a axis it is like x y and z it is to be permanently mounted, not as I had envisiged a removable axis.

This weekend Im going to do a first run program and see what I can make. But in the mean time heres some setup pics

[simso]

Z Sled trimmed down to clear A axis and chuck

[simso]

And side view of an even cut front to rear, my overlapping / passing was kept to a minimum to speed up process

[simso]

Wow, for those that dont have an a axis, its a must. You can make anything. I carved up a few basic jobs today and blew away my own expectations.

My current limitation is lack of 3d drawing programs and post processors, My current goal is to be able to mount a block of wood onto the a axis and then have the xy and z carve out a 3d shape like a horses head etc.

I have visual mill, which appears to be able to post process 3 dimensionally, still having problems but I know its my end thats the problem, but struggling to find a competant drawing package to suit my need, shame vectric dont make one, everything else they do is pretty sweet looking.

[rodm]

Sounds good Steve.
Mach3 support six axes so should not be a problem there. Problem is the drawing and converting to Gcode as you say. Also to get full 3D you will have to articulate the router - you are four fifths of the way there :2tsup:

[simso]

You know rod, I reckon one day that will be a project for me. Articulated router, how cool would that be

[simso]

Heres one of the test jobs I did yesterday, standard square box section from bunnings. Did a bit of engraving down below and then I routed in 30 degree increments the guts out of the block.

Would actually work as a pretty good bedside lamp on a larger scale "the slotted wood that is" drop a light bulb inside and let it glow out of the rebates