Thread: I'd like a fourth axis. :)

Hey mate, no idea on what program they are using. Need one for myself, I now have a new 4 axis board and a A axis ready to go

Steve

Steve that looks good.

Can't make out your gearing method though. Or are you going direct?

Any thoughts of a tail stock?

Yeah software is another issue. You can do cylindrical work by tricking Vcarve. Swapping axis names.

Greg

Yes mate, its a direct drive, the picture doesnt show the main shaft that connects the chuck to the motor. I couldnt see any reason for reduction gearing, I havent made up a tail support yet, becuase my first goal was to design and draw some chess pieces like the rook and carve it out first as a trial, after perfecting this I was going to make a tail support and do pool cues, for the father in law and numerous friends requests,

I will take some better photos this weekened

I just worked out what yopu meant regarding tricking the g code program. your talking about programming your y axis to turn your A, never thought of doing that, but that would work a treat for engraving

Steve

Thought from thread title you wanted the 4th dimension.

That being time so you can go back and fix your mistakes, be handy I reckon )

I have been hoping to find a second hand Jet Mini lathe (or equivalent in another brand). Preferably without a motor to use as the basis for a rotary axis. Had no luck so far.

A forum member, Mugwoody, contacted me to say he had some small right angle reduction gearboxes that were surplus and may fit the bill.

He also said, "don't pay me yet, see if it will suit your purpose first" ...... you can't get fairer than that.

I was a bit sceptical that they would have too much backlash in them but thought I would give it a go and see what happens.

So today I turned up a spindle shaft for it. Went with 1" - 10 tpi which is the same as my wood lathe so that I can use existing chucks etc.

Next step will be make up some mounts to take a Nema 23 stepper motor and give it a try.

Greg

.

Looking forward to see how it progresses.

the 2nd video had a 5th axis. where the router rotated on the mount to cut a pineapple. You could even make a 6th and have the router rotate east-west and north-south.

How are things progressing Greg ?

G'day Willie

I'm a bit snowed under at the moment with family stuff and work.

Progress might be a bit slow right now. Need to order a stepper for it while I'm held up.

Greg

Not a lot of progress right now. Work has got in the way. Don't you hate that.

This little 260oz stepper drives it OK but I think I'll go with a bigger one with a little more torque at faster speeds.

Obviously I need to make a motor mount next.

Then I should be able to do some testing to see if it is going to be a good jigger and proceeded with. I'm optimistic.

Greg

Gee Greg,

Wont be long and we'll be seeing videos like the one above posted by you. Looks great. Im in the process of starting to build my own. Going to direct drive it for now until i can figure out how harmonic drives work and where to get one cheaply etc and ill then upgrade to that.

Daniel

I finally got some shed time today so I knocked up a motor mount for the little stepper I pinched of another machine.

Keen to give it a go I clamped it very dodgy like to the table and "What do you know....It goes!!!!!"

Had to dial in 0.225 degree back lash compensation in Mach3. That amounts to about 0.1mm or 0.004" backlash at 50mm diameter.

Too much backlash to live with but the compensation seems to work OK so far.

I've never done rotary axis stuff before so for a test I used a great little program that bloke called Andrew wrote.

See this link, http://vectric.com/forum/viewtopic.php?t=2920

It takes a gcode file that you have created in 2D and converts it to a rotary axis. Works great.

Anyway as you can see in the pics it all sort of worked as expected. Not bad for a first try.

Greg

Hi Greg,
Quote
Sort of works.

I would be really pleased if my first lash up worked as well as that. Now I am going off to waste another hour reading about converting 2D to 3D.

Keep the posts coming.

Wow!!!

That is so cool, I don't know about the not bad part of that

Congrats Greg!