No 4th axis: Will Helical Interpolation do this?
Close
Login to Your Account
Page 1 of 4 123 ... LastLast
Results 1 to 20 of 64
  1. #1
    Join Date
    May 2006
    Location
    Illinois
    Posts
    230
    Post Thanks / Like
    Likes (Given)
    88
    Likes (Received)
    38

    Default No 4th axis: Will Helical Interpolation do this?

    Have a job opportunity to mill a series of cosmetic windows into the side of 1.25" aluminum tubing and I'm trying to devise a way to deburr the edges without a 4th axis. There will a total of about 1000 windows so I would prefer not to do them by hand.

    The windows are purely cosmetic and the tolerance is very broad. The customer says the main hole can be cut with an end mill through-cut. But to deburr the edge, I need to follow the edge of the finished profile with a chamfer or ball nose. That is where I'm having difficulty.

    Machine is a Mycenter0 with a Yasnac MX3 control.
    It does have helical interpolation but I have very little experience with it other than tapping.
    Also, I've wondered if changing the plane selection, (G18 or G19), would help.

    I've attached a representative image that shows the window in two different shapes. The tilted parallelogram is the shape I would prefer but thought I may have to go with the rectangle if my only option is to use G18 or G19.

    It seems to me there has to be a way to do this since I'm not trying to hold tight tolerances. In fact, the chamfer doesn't even have to be uniform...it just has to knock off the sharp edges.

    Any help would be appreciated!
    gm.
    Attached Thumbnails Attached Thumbnails tube.jpg  

  2. #2
    Join Date
    Feb 2007
    Location
    Aberdeen, UK
    Posts
    3,475
    Post Thanks / Like
    Likes (Given)
    1213
    Likes (Received)
    1296

    Default

    Are you programming by hand or with cam?

  3. #3
    Join Date
    Jun 2012
    Location
    Michigan
    Posts
    4,567
    Post Thanks / Like
    Likes (Given)
    4165
    Likes (Received)
    2722

    Default

    You don't need a 4th axis for that part.

  4. #4
    Join Date
    Sep 2015
    Country
    UNITED STATES
    State/Province
    Ohio
    Posts
    1,062
    Post Thanks / Like
    Likes (Given)
    634
    Likes (Received)
    1025

    Default

    I think I'd just buzz around the inside and outside edges with a lollipop mill.
    Delete the radius off your model and use the sharp edge to generate your code. You can use either the rectangle or trapezoid shape but the rectangle could be forced to convert to G18/G19 to save on code.

    Either way, you're going to have a lot of code to make the edge breaks look halfway descent, so you may want to consider making it a sub-program written in incremental.

  5. #5
    Join Date
    Sep 2015
    Country
    CANADA
    State/Province
    Ontario
    Posts
    92
    Post Thanks / Like
    Likes (Given)
    43
    Likes (Received)
    35

    Default

    Usually for weird shaped chamfers like this I will just surface it with a ballnose endmill.

  6. #6
    Join Date
    Aug 2016
    Country
    ALAND ISLANDS
    Posts
    1,393
    Post Thanks / Like
    Likes (Given)
    43
    Likes (Received)
    96

    Default

    hy

    ... finish toolpath is planar
    ... you compute for each point the height on the cilinder
    ... maybe aproximate the 90degrees at corners with 4*[90/4]degres arches

  7. #7
    Join Date
    May 2006
    Location
    Illinois
    Posts
    230
    Post Thanks / Like
    Likes (Given)
    88
    Likes (Received)
    38

    Default

    Quote Originally Posted by Mtndew View Post
    You don't need a 4th axis for that part.
    I didn't think that it did, but I can't figure out how to simultaneously circularly interpolate the Z-axis while linearly interpolating the X and Y.

    I'm comfortable doing subroutines with looping etc. and could do this with very small linear Z-movements. I just thought there must be an easier way.

  8. #8
    Join Date
    Sep 2015
    Country
    UNITED STATES
    State/Province
    Ohio
    Posts
    1,062
    Post Thanks / Like
    Likes (Given)
    634
    Likes (Received)
    1025

    Default

    Not sure what you mean.
    Chamfer the radius on the inside corner of your pocket?
    G3 XYZIJ Simple 90 degree helix move

    Or chamfer OD of the tube?
    G18/G19 (depending on orientation of the tube)
    G03/G02 (depending on which side of pocket) X/Y (depending on part orientation) I/J, K
    G17 (back to X-Y plane)

  9. #9
    Join Date
    Dec 2011
    Location
    Whitehall, MI
    Posts
    565
    Post Thanks / Like
    Likes (Given)
    116
    Likes (Received)
    139

    Default

    I don't think it will be a "helical" move, but a 3d toolpath with alot of XYZ moves is what it looks like to me. I think you could get a ballnose to trace the edge and look good.

  10. #10
    Join Date
    Sep 2015
    Country
    UNITED STATES
    State/Province
    Ohio
    Posts
    1,062
    Post Thanks / Like
    Likes (Given)
    634
    Likes (Received)
    1025

    Default

    Quote Originally Posted by brian.pallas View Post
    I don't think it will be a "helical" move, but a 3d toolpath with alot of XYZ moves is what it looks like to me. I think you could get a ballnose to trace the edge and look good.
    Probably, but I think you could fake it with a helix and still look descent.
    Especially if he's hand coding it.

  11. #11
    Join Date
    Feb 2013
    Country
    UNITED STATES
    State/Province
    Idaho
    Posts
    650
    Post Thanks / Like
    Likes (Given)
    132
    Likes (Received)
    703

    Default

    That's a piece of cake in Mastercam with the 3D Chamfer tool path. I think it would be exceptionally difficult to program by hand or with conversational programming due to the simultaneous Z moves. Additionally, the program must take into account the changing diameter of the cutter as it either heels in or heels out as the Z plane changes. Here is a sample program of a .020" 3D chamfer on a .5"x.5" pocket on a 1" diameter tube using a 1/4" 45 degree spot drill with a .050" tip clearance. (XYZ Zero in the center of the pocket, top of the tube).
    part1.jpg

    (T5|1/4 SPOT DRILL - 0.25|H5|D5|TOOL DIA. - .25)
    N100 G20
    N110 G0 G17 G40 G49 G80 G90
    (1/4 SPOT DRILL - 0.25|TOOL - 5|DIA. OFF. - 5|LEN. - 5|TOOL DIA. - .25)
    N120 T5 M6
    N130 G0 G90 G54 X.22 Y0. S6000 M3
    N140 G43 H5 Z.3
    N150 M8
    N160 G1 Z-.051 F75.
    N170 Y.0529 Z-.0538 F35.
    N180 Y.1052 Z-.0622
    N190 Y.1557 Z-.076
    N200 X.2197 Y.1632 Z-.0802
    N210 X.2185 Y.1711 Z-.0847
    N220 X.2145 Y.1852 Z-.0943
    N230 X.2081 Y.1979 Z-.1042
    N240 X.1995 Y.2091 Z-.1141
    N250 X.1892 Y.2183 Z-.1232
    N260 X.1833 Y.2221 Z-.1273
    N270 X.1772 Y.2253 Z-.1308
    N280 X.1707 Y.2278 Z-.1337
    N290 X.1639 Y.2297 Z-.1358
    N300 X.1535 Y.2311 Z-.1375
    N310 X-.1535
    N320 X-.164 Y.2297 Z-.1358
    N330 X-.1708 Y.2278 Z-.1336
    N340 X-.1772 Y.2253 Z-.1307
    N350 X-.1834 Y.222 Z-.1272
    N360 X-.1946 Y.214 Z-.1188
    N370 X-.2041 Y.2037 Z-.1092
    N380 X-.2116 Y.1918 Z-.0992
    N390 X-.2169 Y.1783 Z-.0894
    N400 X-.2186 Y.1711 Z-.0847
    N410 X-.2199 Y.16 Z-.0781
    N420 X-.22 Y.1557 Z-.076
    N430 Y.1052 Z-.0622
    N440 Y.0529 Z-.0538
    N450 Y0. Z-.051
    N460 Y-.0529 Z-.0538
    N470 Y-.1052 Z-.0622
    N480 Y-.1557 Z-.076
    N490 X-.2197 Y-.1632 Z-.0802
    N500 X-.2185 Y-.1711 Z-.0847
    N510 X-.2145 Y-.1852 Z-.0943
    N520 X-.2081 Y-.1979 Z-.1042
    N530 X-.1995 Y-.2091 Z-.1141
    N540 X-.1892 Y-.2183 Z-.1232
    N550 X-.1833 Y-.2221 Z-.1273
    N560 X-.1772 Y-.2253 Z-.1308
    N570 X-.1707 Y-.2278 Z-.1337
    N580 X-.1639 Y-.2297 Z-.1358
    N590 X-.1535 Y-.2311 Z-.1375
    N600 X.1535
    N610 X.164 Y-.2297 Z-.1358
    N620 X.1708 Y-.2278 Z-.1336
    N630 X.1772 Y-.2253 Z-.1307
    N640 X.1834 Y-.222 Z-.1272
    N650 X.1946 Y-.214 Z-.1188
    N660 X.2041 Y-.2037 Z-.1092
    N670 X.2116 Y-.1918 Z-.0992
    N680 X.2169 Y-.1783 Z-.0894
    N690 X.2186 Y-.1711 Z-.0847
    N700 X.2199 Y-.16 Z-.0781
    N710 X.22 Y-.1557 Z-.076
    N720 Y-.1052 Z-.0622
    N730 Y-.0529 Z-.0538
    N740 Y0. Z-.051
    N750 G0 Z.25
    N760 M5
    N770 G91 G28 Z0. M9
    N780 G28 X0. Y0.
    N790 M30

  12. Likes doug925 liked this post
  13. #12
    Join Date
    Aug 2016
    Country
    ALAND ISLANDS
    Posts
    1,393
    Post Thanks / Like
    Likes (Given)
    43
    Likes (Received)
    96

    Default

    try 4+4*3+2+2=20 lines

    4 : for the sides : 2 constant Z + 2 variable Z
    4*3 : 4 corner arches * 3 segments each
    2 : in & out movement in XY plane
    2 : in & out movement among Z axis

  14. #13
    Join Date
    Nov 2002
    Country
    UNITED STATES
    State/Province
    Texas
    Posts
    3,242
    Post Thanks / Like
    Likes (Given)
    1818
    Likes (Received)
    800

    Default

    As said prior, this is just 3D profiling (plannar) OR you could extract the edge of the pocket where you need to chamfer. Offset the shape by the 1/3 the tool radius. This is your centerline path of the tool.
    By moving the entity in Z- you will increase the amount of chamfer your chamfer mill will generate.

    Doug.

  15. #14
    Join Date
    May 2006
    Location
    Illinois
    Posts
    230
    Post Thanks / Like
    Likes (Given)
    88
    Likes (Received)
    38

    Default

    Thanks for the feedback Brian and Booze.

    And yes, I'm hand coding this.

    A 3D toolpath is what I thought it would need as well and I didn't know if there was a g-code that would allow me to move the X&Y and one feed rate while simultaneously moving the Z at a different feed. That would be one way I could see doing it without having to make a bunch of small discrete moves.

    The second way I thought was to use a helical motion but, again, I still consider myself a novice on a lot of this and am not quite sure how this.

    To answer your question Booze, the goal is to relieve the sharp edge of the window on the OD of the tube.

  16. #15
    Join Date
    May 2006
    Location
    Burlington, North Carolina
    Posts
    379
    Post Thanks / Like
    Likes (Given)
    418
    Likes (Received)
    143

    Default

    Would tumbling work?

  17. #16
    skywalker4 Guest

    Default

    there is a real nice deburr tool made just for this.
    ezburr.com, or jwdone.com both make nice products.

  18. #17
    Join Date
    Sep 2015
    Country
    UNITED STATES
    State/Province
    Ohio
    Posts
    1,062
    Post Thanks / Like
    Likes (Given)
    634
    Likes (Received)
    1025

    Default

    On the internal pocket corners, the Z is going to change non-linearly as you complete the arc.
    Smaller Z moves per XY at the beginning, larger Z move per XY at the end. There isn't a G code to do that.

    Best I could suggest is to look at your solid and explode that radius into lines and inquire the end point at the beginning, middle and end of the arc.
    Program 2 helix moves.
    G01 XYZ (beginning of arc)
    G3 XYZ IJ (middle of arc)
    G3 XYZ IJ (end of arc)

    You should be able to get a reasonable looking chamfer.

    Or post the size of the pocket, inside corner radius and tube OD and I'm sure someone would be willing to run it thru their CAM and post the code.

  19. #18
    Join Date
    May 2006
    Location
    Illinois
    Posts
    230
    Post Thanks / Like
    Likes (Given)
    88
    Likes (Received)
    38

    Default

    Thanks Booze. That makes a lot of sense.

    I've ordered some scrap tubing to play with this weekend. We'll see how it looks.
    gm

  20. #19
    Join Date
    May 2006
    Location
    Illinois
    Posts
    230
    Post Thanks / Like
    Likes (Given)
    88
    Likes (Received)
    38

    Default

    Quote Originally Posted by aj View Post
    Would tumbling work?
    Thought of tumbling but it would degrade other features that require a tighter tolerance.

  21. #20
    Join Date
    Jun 2012
    Location
    Michigan
    Posts
    4,567
    Post Thanks / Like
    Likes (Given)
    4165
    Likes (Received)
    2722

    Default

    Quote Originally Posted by gmoushon View Post
    And yes, I'm hand coding this.
    Why??
    If you have 1,000 of them to do, why not find a shop with a CAD/CAM program and pay them $100 to write a quick program for you? It would take them 15 minutes tops.


Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •