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Re: 4th axis engraving ??

PostPosted: Fri Jan 19, 2018 2:40 am
by velvetpig
Hi Vmax549,
I would be very interested as i do 4th axis work- YtoA.
At the moment i have to change over to Mach3 for 4th Axis work.
It would be nice to stay with UCCNC.
Cheers

Re: 4th axis engraving ??

PostPosted: Fri Jan 19, 2018 11:14 am
by Greolt
Interested to see what you come up with.

Re: 4th axis engraving ??

PostPosted: Fri Jan 19, 2018 11:18 am
by velvetpig
That would be great.
I am a new user of UCCNC, I Appreciate the work you and others do to make the changeover interesting.
Testing Plugins and Macros ect
Cheers

Re: 4th axis engraving ??

PostPosted: Fri Jan 19, 2018 12:49 pm
by ger21
CNC Drive has plans to implement the required 4th axis features, they just haven't gotten to it yet.

Re: 4th axis engraving ??

PostPosted: Fri Jan 19, 2018 12:51 pm
by cncdrive
Yes, we do. What I think is missing is selectable constant surface speed over radius of the workpiece and if we want to make it really nice then 4-axis toolpath view.
And yes, we really did not get to it yet, we still working on other things at the moment.

Re: 4th axis engraving ??

PostPosted: Fri Jan 19, 2018 1:16 pm
by Gary Campbell
One thing to think about. While constant speed at the surface is virtually necessary on a lathe while turning. My experience has shown me that it is counterintuitive to wood routing on a 4th axis rotary. Having the rotary feedrate increase as the bit plunges deeper just does not work.

There could be some very minor advantage of feedrate increase on a rotary Z level rouging pass, but running a 3D rotary finish path with the feature enabled appears (to a human) to be the worst option available. Watching a small diameter tapered ballnose slow at the surface and then increase as it plunges deeper appears to be and is wrong. On a lathe the feature provides a constant load on the tool, on a rotary axis it actually makes sure the chipload is never consistent

Careful what you wish for.

Re: 4th axis engraving ??

PostPosted: Fri Jan 19, 2018 3:36 pm
by Gary Campbell
In my rotary work, I did the opposite. Using a viable XY feedrate to determine an equivalent diameter based rotary feedrate.

Using the formula F{(115)*(XY feed)/(DIA)}A or {(360/pi) * (feed) / (DIA) returns a surface feed for the rotary. Note: My experience is based on using Vectric rotary wrapped machining, but the math is the same.

Here is an example showing how a diametrical feed increase would be devastating: https://youtu.be/9bLnP9R7bE0

During the flute cuts you can see that the feedrates are slowed by a slow (10ipm) Z feedrate during the sections that are closer to vertical

Re: 4th axis engraving ??

PostPosted: Sat Jan 20, 2018 7:52 pm
by Gary Campbell
X axis:
Steps per inch 8128
Velocity 300
Accel 50

Sorry, but there is no 4th axis on this machine. But there may be soon, customer is waffling. These settings would be
A axis:
Steps per degree 44.4444
Velocity 36000
Accel 3000

Re: 4th axis engraving ??

PostPosted: Sat Jan 20, 2018 9:44 pm
by Gary Campbell
Not until "the proud new Owner" purchases the rotary fixture

Re: 4th axis engraving ??

PostPosted: Mon Jan 22, 2018 8:28 am
by alex_s
just an understanding question, is this only needed if your CAM can not do full 4 Axis ? or if u want to put an existing engraving on a round stock ?

cheers
Alex