[turbostang]

I am currently using a BP Series 1 with Centroid controls. I am soon to get rid of it for the simple fact that it's X axis is limited to 15.xx" - when I first got the mill it was great and quickly I found out I needed more travel.

So, now that brings me to my next dilema - bieng the hobbyist / fabricator that I am a simple 3 axis CNC is not "enough". I've dreamed up some 5 axis plans (nothing on CAD yet) and it actually seems easy enough to create...but I haven't seen a single build thread on a 5 axis DIY machine. I've searched for ever it seems and can't find anything. Maybe I have bad search terms or something..

So, here I ask.. I am looking for pics, links, videos to some good ol' DIY 5 axis setups..

post away cnczoners!

[mackeym]

I'd like to see a CAD of what you have in mind.

[digits]

Unless you are planning a 3+2 axis machine, I think CAM will be your biggest (or rather most expensive) problem. Getting zero-backlash on your rotary axes might also be tricky though.


There is a nice video of a DIY 5-axis running EMC2 here:
http://www.cnczone.com/forums/showthread.php?t=60243


Good luck!

[turbostang]

I'd like to see a CAD of what you have in mind.

I am not that good at any sort of CAD anything just yet, but wait...

My wife is a programmer, I'll get her to do it for me!

Unless you are planning a 3+2 axis machine, I think CAM will be your biggest (or rather most expensive) problem. Getting zero-backlash on your rotary axes might also be tricky though.

There is a nice video of a DIY 5-axis running EMC2 here:
http://www.cnczone.com/forums/showthread.php?t=60243

Good luck!

The first 3rd video in that thread is a lot like what I had in mind. The rotary portion would be my only concern, like you said, zero backlash would be hard to achieve.

My "design" would be a lot like what you see in the video - except that the stepper for the rotary would be next to the rotary table with the stepper pulley pointing down. The rotary would have a timing pulley attached to the bottom, and of course the timing belt between the two. What kind of lash can you expect from that arrangement?

Otherwise I have 2 more choices.. one bieng to put the stepper on the bottom of the rotory table with direct drive - but there would be a height concern most likely. The 2nd option would be like what is posted in the first video - but on a larger scale. My concern with that design would be the weight of the head and the difficulty keeping it trammed.

Thoughts? Ideas? Suggestions?

[digits]

If you drive the rotary table via the 'handle' then you will have the backlash between the table's worm wheel and worm gear to worry about as well.

If you direct drive it, you will lose the 90:1 gearing advantage that the worm gear gives you - I'd imagine a 200Nm stepper would be rather expensive if it even exists!

What do you plan to mill, and what sorts of cutting forces and speeds do you need?

[turbostang]

If you drive the rotary table via the 'handle' then you will have the backlash between the table's worm wheel and worm gear to worry about as well.

If you direct drive it, you will lose the 90:1 gearing advantage that the worm gear gives you - I'd imagine a 200Nm stepper would be rather expensive if it even exists!

What do you plan to mill, and what sorts of cutting forces and speeds do you need?

It won't be a worked over rotary table if I can help it. That is the kind of info I need though, I am not really familiar with the abilities of the steppers in terms of Nm... and directly driving the rotary portion of the axis would not really be a "good" option because of the height it will take away from Z.

What kind of lash would be realistick from a timing pulley arrangement?

The goal is to use a bolt on 6" 3 jaw chuck. The stepper to rotate the chuck will sit right next to it with the shaft pointing down. A timing pulley on it, one on the bottom of the chuck and a belt in between. All of this will sit on a gantry of sorts that rotates in the opposite plane.

Not sure on the speeds and or forces, but, fwiw, it will be based around a Grizzly G0519 most likely. That should give you some idea.

edit - I don't expect to be cutting anything other than aluminum or 1018 with cutters .625 or smaller. most likely smaller.

[sansbury]

The reason you don't see a lot more DIY 5-axis machines is simple: you have to spend more on software than on the mill to do anything useful.

Anybody who can hack together a CNC mill and use it will be able to build a 5-axis trunnion table-type setup. It's not hard and Mach and EMC2 can both run 5 axes. However, I think the cheapest CAM to run it is MasterCAM, and that's in the mid-thousands. 4-axis is considerably simpler though and you can get into the edges of it with free/low cost S/W and BobCAD has some support for it for real money but I think a good deal less than MasterCAM.

There is a use case for a 5-axis design to serve as basically a fancy fixture, e.g., to mill or drill on 5 faces of a cube. In this case the axes simply allow you to reposition the workpiece for conventional 3-axis milling without having to do a whole new setup using g-codes that can be calculated by hand or determined experimentally. Whether this is worth the trouble depends on your parts and how many of them you make. My suspicion is that it's not, for the vast majority of us, and thus why you don't see more 5-axis machines.

[nateman_doo]

The reason you don't see a lot more DIY 5-axis machines is simple: you have to spend more on software than on the mill to do anything useful.

Anybody who can hack together a CNC mill and use it will be able to build a 5-axis trunnion table-type setup.

^THIS

I could build one... but I have NOOOOO idea how the cam works. It would take me months to probably learn to use a 4th axis, and then the 5th would break me.

[hesham morsy]

5Axis Software 5Axis Gantry Router 5Axis Benchtop Mill
http://www.rainnea.com/cnc

[digits]

That's interesting looking software, but it doesn't look like a complete 5-axis solution to me. I'd really want to be able to simulate a 5-axis tool path before I let it run on a real machine - there are just so many more exciting ways to crash a 5-axis than a 3-axis!

[RalcoBe]

I made a:

3D pointclaw scanner,
converter to solid,
path recognizer,
route generator,
dnc code generator.
All in Labview.

In 5 axis mode, not only the digitizer has to be better,
also the routing generator hast to be completely something else.
I don't see myself construction something like this, nor quickly use existing software who can.

[judleroy]

Check out these links. www.cnc-toolkit.com and www.doughtydrive.com/products.html Good luck.

[diegope]

anybody has any updates on this? we're looking at building a 4/5 axis...but not sure of its feasibility. any body knows of kits out there? thanks, d

[khoac3]

https://www.youtube.com/watch?v=cycKPTyPjEY





A friend of mine spent 3 years on research and making this tiny little machine for his work.