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Gcode tools - lathe extension develop

Добавлено: 08 апр 2010, 09:25
Nick

Gcode tools - lathe extension develop

Questions to discus

  1. Cutting tool parameters
  2. Additional lathe parameters
  3. Lathe's Gcode features
  4. Special places
  5. ...

Desired features list

  1. Special mode for 4axis mills
  2. Automatic flip along axis

Awaiting of realization

  1. Automatic flip along axis

Done

  1. Path calculation
  2. Export path to gcode
  3. Defailt X and Z axis remap

Re: Gcode tools - lathe extension develop

Добавлено: 08 апр 2010, 09:41
Nick
Another question:
How to cut this place? How to determine such special places?
gcode lathe 0036.png (15381 просмотр) <a class='original' href='./download/file.php?id=486&sid=b01d79b76a7d7357a9262392d49fa3e4&mode=view' target=_blank>Загрузить оригинал (31.9 КБ)</a>
By the way, clones can be used to draw bottom part of the path. If you change original's geometry clone will be also changed.

Re: Gcode tools - lathe extension develop

Добавлено: 08 апр 2010, 17:24
alfcnc
Hi !
I think that turning path with angle zone so sophisticated require a four axis turning system.
Whit simple turning machine it's possible to do some case but it's more harder ! That require special tools ! And special nc code.
And we must take care of the geometry of the turning tool ... it's ever more sophisticated.

Can we just in the first state of feature ! Have generation for simple path ! just with no dead angle.
In the first time that's be the user that must becarufull of the angle of his path to don't have problem in cuting his path.

In second evolution we can improve to have tool consideration and special shape generation...

Re: Gcode tools - lathe extension develop

Добавлено: 08 апр 2010, 17:58
Nick
Ok... But before we start let's discuss a little on all questions mentioned above.
It will help me to see the whole picture and I will be able to do further improvements without rewriting the code from the very beginning.

1. What parameters do cutters have? I remember from my school lessons that there are several types of cutters. What are that types, which of them we will use at the first realisations? which won't?
2. What parameters do lathes have?

PS we are about to release a new version. So we are not coding any new functions until release. We've set deadline to next Friday (April 16). Tuis is another reason to to discus the thin places.

Re: Gcode tools - lathe extension develop

Добавлено: 10 апр 2010, 17:13
alfcnc
Hi ! after some search I found this doc.
Resume some parameters of coordinate system and the tool working face of cnc lathe.
coordinate_system_of_lathe.jpg (15339 просмотров) <a class='original' href='./download/file.php?id=488&sid=b01d79b76a7d7357a9262392d49fa3e4&mode=view' target=_blank>Загрузить оригинал (36.16 КБ)</a>

Re: Gcode tools - lathe extension develop

Добавлено: 12 апр 2010, 09:11
Nick
alfcnc писал(а):Hi ! after some search I found this doc.
Resume some parameters of coordinate system and the tool working face of cnc lathe.
We'll have to use G18 code to be able to use G02 and G03 codes.

Re: Gcode tools - lathe extension develop

Добавлено: 13 апр 2010, 12:59
alfcnc
I think that's be nice to have the choice off two major mode.
One mode for native lathe turning ! Classical setting XZ axis and spindle.
And one mode for turning on 4 axis center of type 3 axis milling with a rotational servo axis or a spindle for rotary axis that's is often along X axis.
And perhaps be able to select were the X and y axis and z axis are setting. And then set/unset A axis for adjust to the different case if it's a servo or just a spindle.

I speak off this type of center:
5980multipurposemachine.jpg
5980multipurposemachine.jpg (13.04 КБ) 15322 просмотра
Or with servo/stepper type config... the A axis done the job of spindle on lathe.
But the tool is different because using the milling tool on the z spindle...
sherline.jpg (15322 просмотра) <a class='original' href='./download/file.php?id=490&sid=b01d79b76a7d7357a9262392d49fa3e4&mode=view' target=_blank>Загрузить оригинал (44.34 КБ)</a>

Re: Gcode tools - lathe extension develop

Добавлено: 13 апр 2010, 13:47
Nick
alfcnc писал(а):I think that's be nice to have the choice off two major mode.
One mode for native lathe turning ! Classical setting XZ axis and spindle.
And one mode for turning on 4 axis center of type 3 axis milling with a rotational servo axis or a spindle for rotary axis that's is often along X axis.
And perhaps be able to select were the X and y axis and z axis are setting. And then set/unset A axis for adjust to the different case if it's a servo or just a spindle.
Ok, I'll put in the header in the desired list.

About the trajectory of cutting tool is there any special things?
Can you write a simple algorithm on which cutting is usually made?
Is there any common thing that you cut with cnc lathe?

Re: Gcode tools - lathe extension develop

Добавлено: 13 апр 2010, 15:33
alfcnc
I'll try to give some answer to your question.
But wait a little for found the time.
Thank's.

Re: Gcode tools - lathe extension develop

Добавлено: 13 апр 2010, 16:53
alfcnc
a simple exemple for lathe mode is the one give with emc:
emc_exemple.jpg (15319 просмотров) <a class='original' href='./download/file.php?id=491&sid=b01d79b76a7d7357a9262392d49fa3e4&mode=view' target=_blank>Загрузить оригинал (26 КБ)</a>
nc file:
lathe_pawn.ngc
(2.13 КБ) 1644 скачивания

Re: Gcode tools - lathe extension develop

Добавлено: 13 апр 2010, 18:20
Nick
Let's take a closer look...

If I wrong with something please correct me.
Horizontal lines are major cutting trajectory which cut most of material.
What do diagonals from bottom right to top left do? Is it a penetration trajectory?
And two curvy paths are the finishing trajectory.
What cutter is used to cut this thing?

Re: Gcode tools - lathe extension develop

Добавлено: 06 май 2010, 17:03
Nick
So as we've made a release. I'm coming back to lathe development :).

First step is ready: Generate parallel lines and calculate their intersection with the path.

Re: Gcode tools - lathe extension develop

Добавлено: 07 май 2010, 13:29
Nick
Now I'm thinking adding penetration trajectory.
As I know penetration is not always done with the right (90 deg) angle.

Re: Gcode tools - lathe extension develop

Добавлено: 17 май 2010, 13:08
alfcnc
Yes ! The penetration angle is different with material to cut !
And different with the type of tools...
I think for single point surface the tool angle can be set the more obvious to be able to cut all the shape
when finishing pass.
I've found some documentation about lathe would you that I send you this ?

Re: Gcode tools - lathe extension develop

Добавлено: 17 май 2010, 13:11
alfcnc
root писал(а):So as we've made a release. I'm coming back to lathe development :).

First step is ready: Generate parallel lines and calculate their intersection with the path.
I have download ver 1.6 and try to run the lathe tab... but any result !is the parellel algorithme usable now ?

Re: Gcode tools - lathe extension develop

Добавлено: 18 май 2010, 12:44
Nick
alfcnc писал(а):I have download ver 1.6 and try to run the lathe tab... but any result !is the parellel algorithme usable now ?
No :), it is in the development. I'm thinking about how to make cutting trajectory from this parallel lines and intersection dots?
How should penetration trajectory looks like?

Re: Gcode tools - lathe extension develop

Добавлено: 21 май 2010, 22:57
alfcnc
I think the cutting path would be like this for axial cutting...
lathe_path.png (15150 просмотров) <a class='original' href='./download/file.php?id=521&sid=b01d79b76a7d7357a9262392d49fa3e4&mode=view' target=_blank>Загрузить оригинал (398.29 КБ)</a>
I think for good finishing surface that's be nice to have abilities to define 2 , 3 , or more final path with a different depht
cutting layer to have very thin pass cutting at the near end of the cutting process... this allow the real final path to be a very very thin cutting and this done good accuracy of cutting and better surface looking... (but this depend of the material to cut, wood , metal , plastic). If requires different final cutting parameters and if wanting very high surface finishing quality you must put another tool... But with ceramic carbids tool and some thin pass to the end of cuting the result are often very good for metal cutting. :idea:

Re: Gcode tools - lathe extension develop

Добавлено: 30 июн 2010, 12:39
Nick
I'm sorry for the delay with lathe... I was really busy this time and spent all my free time to write offset function, which will be also needed in lathe to make final fine cut.

But here's some new results! :)

I've made a function which generates paths that could be exported to gcode later. Now I've stopped at gcode exporting. Here some problems:
1. We already have generate_gcode function, but it is focused on generate gcode for mills, not lathes. So I think we will need a new function to generate lathe gcode.
2. What parameters should we add?
3. What axes should we use?

Here are an illustration for the function I've made. How do you think, what must be improved in this function?
0045 gcode tools lathe.png (15070 просмотров) <a class='original' href='./download/file.php?id=543&sid=b01d79b76a7d7357a9262392d49fa3e4&mode=view' target=_blank>Загрузить оригинал (20.28 КБ)</a>
Also there's some different types of subpath:
blue - the subpath have been already cut, go through it at maximum speed
red - cut at depth step (the final path will be cut next steps)
green - cut the path
0046 gcode tools lathe.png (15068 просмотров) <a class='original' href='./download/file.php?id=545&sid=b01d79b76a7d7357a9262392d49fa3e4&mode=view' target=_blank>Загрузить оригинал (25.99 КБ)</a>

Re: Gcode tools - lathe extension develop

Добавлено: 07 июл 2010, 18:42
alfcnc
Hi ! root !

Very nice !

I think to others improvement just for final tool path !
But all it is very good for me.

For final path just be able to set the speed of it and the number
of fine final cutting path...

so I see parameters...

Feed of roughing cut or speed cut...
Depth pass of roughing cut.
Feed of end cut.
Depth pass of ending cut.
I want say that's very nice to be able to have a parameters for reapeat n times
the end cut.. often I do 2 too 3 time the end cut to have a very good surface finishing...
and a paramater to subdivide the end depth cutting path.

Re: Gcode tools - lathe extension develop

Добавлено: 07 июл 2010, 19:13
alfcnc
alfcnc писал(а):Hi ! root !

Very nice !

I think to others improvement just for final tool path !
But all it is very good for me.

For final path just be able to set the speed of it and the number
of fine final cutting path...

so I see parameters...

Feed of roughing cut or speed cut...
Depth pass of roughing cut.
Feed of end cut.
Depth pass of ending cut.
I want say that's very nice to be able to have a parameters for reapeat n times
the end cut.. often I do 2 too 3 time the end cut to have a very good surface finishing...
and a paramater to subdivide the end depth cutting path.
For the Axes setting that's be nice to be able to name the axes same as wanted...
So if i want Z to be done by my X axis... be able to set X ... and if i want
to set Y for X be able to and so on... that's permit to be able to use a mill for
doing vertical milling or others...

I see some choose box like this... default to Z and X but be able to change it...
lathe_choice_of_axes.png
lathe_choice_of_axes.png (6.14 КБ) 15034 просмотра