Limits of a 3-axis router?

[Chris_F]

I'm planning on building a 3-axis cnc wood router, but before I get started, I better find out if it could even do what I need it to.

My question is this: What would be the limits of a 3-axis router as far as what designs could I cut with it?

For instance, I want to cut out a model of a head. Would I not be able to do that because there are places where the drill couldn't reach without rotating? Or could I just do one pass and flip the wood over onto another side and get the rest in a second pass?

[Switcher]

For instance, I want to cut out a model of a head. Would I not be able to do that because there are places where the drill couldn't reach without rotating? Or could I just do one pass and flip the wood over onto another side and get the rest in a second pass?

Look into the new Cut3D by Vectric. Sounds like the Model Slicing, might work for you.


http://www.vectric.com/WebSite/Vectr.../c3d_index.htm





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[wcarrothers1]

I hope to add Cut3d to my collection of vectric software. Although I also need to find some time to play with what I have (machine and software).. Although I'm sure their cut3d will be great to use as Vcarve and PhotoCarve..

I've only had time to give cut3d a quick look but it does look great..
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Should make 3 axis routers be able to cut out things like heads.. But will have to see how easy it will be to align the part up for the different axis cuts.

b.

[Chris_F]

Yeah, my concern was that my model would have undercut areas. Could Cut3D handle that?

[ger21]

You'll have to flip it and cut both sides seperately, and possibly all 4 sides, rotating 90 degree's between programs. Alignment might be an issue, or, you could add a 4th rotary axis which would do the rotations for you, keeping everything lined up.

[Chris_F]

Originally Posted by ger21 You'll have to flip it and cut both sides seperately, and possibly all 4 sides, rotating 90 degree's between programs. Alignment might be an issue, or, you could add a 4th rotary axis which would do the rotations for you, keeping everything lined up.

Got any links to some info on making a 4-axis mill? Would that be much more difficult than a 3-axis?

[ger21]

You take a 3 axis router and mount a rotary axis to hold the work. Similar to mounting a wood lathe on the table. With the rotary axis, you could even get away with 2 linear axis (X and Z) as most inexspensive CAM software doesn't use all 4 axis together. Not a real good picture, but check out the Indexer that ShopBot sells. http://www.shopbottools.com/accessories.htm

[Chris_F]

If I add a 4th axis that rotated the entire object what all would that solve the undercut problem?

What programs could I use if I do go with that idea?

Also, would it be practical if I was working on somthing large?