more 5 axis post-processor questions

[smiffy]

Hi guys, this is my first posting so please be gentle.

I am configuring a 5axis post for a vertical machine with a tilt/rotary table. My question is do I need to turn top_mapping on to be able use the post for multi-axis positioning work (3+2).

 

 

Thanks Guys.

[DavidB]

Welcome to the Forum Mr Smiffy (finally)

 

[Steve Biehl - Cimquest Inc]

'top_mapping' ???

 

Are you on V9.1Sp2 or MR0304?

Are you starting with the MPGEN5X_FANUC or _MILLPLUS post?

 

They do 3+2 and true 5 after getting the axis vectors set correctly. Do a search for '3+2' and '5 axis' on the forum.

 

BTW Welcome to the forum.

[gcode]

I may be totaly wrong here, but I don't think

a tilt/rotary 5X can even use the top/mapping features.

I've worked on several posts, both titling table and tilting head and never messed with the top/mapping stuff.

Its an expensive add-on for most machine controls, and none of the machines I've worked with support it.

The post will work fine if you leave the topmapping stuff at their defualt settings.

 

Welcome to the forum!

[DavidB]

#Assign axis address

str_pri_axis "A"

str_sec_axis "B"

str_dum_axis "C"

 

#Toolplane mapped to top angle position strings

str_n_a_axis "C"

str_n_b_axis "B"

str_n_c_axis "A"

 

This is what question is refering to.

[gcode]

I come by this knowldge 3rd hand, so take it for what its worth

 

On a typical tilting head machine, project a 2D toolpath onto an irregular plane. The posted code

will be several hunded K worth of tiny G01 moves.

 

With machines that support plane mapping, the post can output a preperatory gcode, a plane

definition and the 2D contour as a typical G01

G02 G03 manreadable and editable toolpath.

 

I can't imagine a tilting table 5x machine doing this cause the spindle is always perpendicular

to the X and Y axis.

 

I know you can ignore the topmapping stuff and get a useable post cause I've done it.

 

I've found the easiest way to work up a good 5X post is to get PROVEN gcode running properly on

Vericut or Predator VCNC. Once you know that Vericut/Predator is properly simulatiing proven code, you can crash your virtual 5X machine all day long trying out new post modifications.

 

 

edit: Glen, Step in here and save me before I get my foot totally stuck in my mouth

[crazy^millman]

Welcome ot the forum. I am thinking you do not want to use top mapping but have your post set-up to work like a normal 5 axis machine. The idea is that is you have a part turned with a face towards X- and your A axi faces that way and b is at -90 that way then when you program that face with your cplane the post would turn the A axis and thenthe b axis to make the part face straight up thus your G code would be just like written for regular just needed to get the axis to the right place. If you do axis mapping then you really defeat the purpose of the post by putting everything where you want it with the indexer moves. With a machine where the head moves that is a different ball game and if the machine has automatic compentaion then you get a set length to use in the post and then the machine will make up any difference from that like to output the correct code.

 

HTH

[smiffy]

OK. Thanks everyone. Currently we are running SP2 and I am starting with MPGEN5X_FANUC. What I did was create simple profiles in the top, side and front views and then another at an angle of 30 degrees and used the cplane and Tplane to produce the toolpath. To test my primary and secondary settings I posted each operation one at a time to view the indexed positions and they look correct. However, when I post all the operations together instead of getting an index, for example from A0 B0 to A0. B90. I get the following:-

 

G0 G54 G90 X-20. Y-10. C0. B0. S5000 M3

G43 H1 Z60. M8

G1 Z0. F650.

Y10. F1300.

Z10.

G0 Z50.

( SIDE VIEW )

B5.

X-23.222 Y6.667

Z45.556

B10.

X-26.444 Y3.333

Z41.111

B15.

X-29.667 Y0.

Z36.667

B20.

until the final move which is correct.

It looks like the "brk_max_ang" is taking control.

 

Try to toolpath a line in the top view then a line in the side view. Post them both together using the default MPGEN5X_FANUC post and you will see what you get.

 

Thanks again

[gcode]

smiffy check out this thread

It shows the correct settings for a rotaty table on a tiltling axis

 

 

Another 5X post thread

 

Its counter-intuative, but with a rotary on a tilting axis, the rotary is the primary, even though it is the driven axis.

 

A post wizard explained it to me once, but it went right over my head

[DavidB]

Mr Smiffy have a look at the Misc Values box on the toolpath.There are a lot of different intergas and reals.

 

I tryed also turning the WCS off and just use C/plane and T/plane in the toolpath it self but same result.It does not index the geometry for 3+2 programming it looks like 5-axis code.

[DavidB]

Mr Smiffy if u turn debugging on this is where its getting the Rotations??????

 

pmx0 p__26:1213 74

 

Good Luck

[MIL-TFP-41]

have a look here in your post

 

code:

---

brk_mv_head : 0     #Break the 5 axis moves to remove gouge

brk_max_ang : 0 #'brk_mv_head' maximum angle move, applied if chordal

#calculation angles moves are greater (negative disables)

skp_rdnt_ck : 0 #Skip 'brk_max_ang' redundant angle check

---

I am just guessing that your brk_mv_head is set at 1.

 

make sure that you are using the latest version of MPGEN5X, it is on the Mcam 9.1 SP2 CD. Also make sure that you update all of you .dll's with the latest & greatest.

[Don S at Barefoot CNC South]

Hi,

What machine and rotary are you using, I just created a 5 axis post using the same generic as you maybe I can help you out with rotation and limits.

 

Don S

[DavidB]

Don S,

 

I put the pics of the machine on the FTP site under all_pictures.picture 019 and 020 dated 6/7/04.

 

 

[DavidB]

Mr Smiffy have a look at this in the post:

 

brk_mv_head : 0 #Break the 5 axis moves to remove gouge

brk_max_ang : 5 #'brk_mv_head' maximum angle move, applied if chordal

#calculation angles moves are greater (negative disables)

skp_rdnt_ck : 0 #Skip 'brk_max_ang' redundant angle check

 

brk_max_ang : 5?????????????????????

 

[smiffy]

I have looked at brk_mv_head and it is set to 0. The machine is a Hitachi Seiki VK45 with the 'A' axis rotating around the Z axis and the 'B' axis tilting around the Y axis, which is limited to -20° and positive 110°. The settings I have which appear to be correct are.

 

str_pri_axis "A"

str_sec_axis "B"

str_dum_axis "C"

 

#Toolplane mapped to top angle position strings

str_n_a_axis "C" # original a

str_n_b_axis "B" # original b

str_n_c_axis "A" # original c

 

#Machine rotary routine settings

mtype : 0 #Machine type

 

rotaxis1 = vecx #Zero

rotdir1 = -vecy #Direction

 

 

rotaxis2 = vecz #Zero

rotdir2 = vecx #Direction

 

p_nut_restore #Postblock, restores original axis settings

result = updgbl(rotaxis1, vecx) #Zero

result = updgbl(rotdir1, -vecy) #Direction

result = updgbl(rotaxis2, vecz) #Zero

result = updgbl(rotdir2, vecx) #Direction

 

saxisx : 0 #The axis offset direction?

saxisy : 0 #The axis offset direction?

saxisz : -90 #The axis offset direction?

 

primary

pri_limlo : -9999

pri_limhi : 9999

#Set intermediate angle, in limits, for post to reposition machine

pri_intlo : -9999

pri_inthi : 9999

 

#Set the absolute angles for axis travel on secondary

sec_limlo : -20

sec_limhi : 110

#Set intermediate angle, in limits, for post to reposition machine

sec_intlo : -15

sec_inthi : 105

 

By the way gents the post version I am using is MP9.10

[gcode]

Are you getting good code??

 

BTW

MPV9.19 is avaiable for downlaod from this website.

It is always a good idea to keep MP.dll current.

[crazy^millman]

Smitty you have a big problem with your settings.

code:

---

primary

pri_limlo : -9999

pri_limhi : 9999

#Set intermediate angle, in limits, for post to reposition machine

pri_intlo : -9999

pri_inthi : 9999

---

Here is where you are going ot have your biggest fit with anythign you try to post. The post need to know there are limits to the place the index angles can go the setting in the sec section are where the post will try to do the work the prim are where the post looks to for it abosulte drop dead stops. If you get an alrm on your machine at -20.001 then the prim need to be -20 and the other sec set at -19. so that you give the post a buffer so to speak to do thing where it needs for calucations to switch the part to another place ot start ot remachien the area where it left off. I ma thiking you might have a dgree or 2 past -20 before you get an alram so that would be the limits at prim. Take a look here and see if this helps you along can not say it is a fix but in my humble opinion could be cuaing you some trouble.

 

HTH

[DavidB]

Millman:

The primary can rotate 360 degrees any direction any number of times.The only limit is on the secondary rotary axis.

 

[jplecan]

Hi Smiffy,

I did what you said to post all the operations at the same time instead of individually on a part of mine, and saw the same thing. What DavidB said about brk_max_ang being set to 5 made sense so I changed that to 90 and since all of my toolpaths were less than 90 deg apart , it got rid of all the 5 deg increment rapid rotary moves.

 

Jim

[smiffy]

Thanks Jim,

 

I have changed the same settings and it appears to fix the problem.

[crazy^millman]

Ok well was not sure so yeah would not matter.

 

All in helping others some times you get it right and soemtimes you get it wrong but atleast I make a effort.

 

Good luck and looks like you got it going your way.

 

[jplecan]

Ron teh Crazy Millman,

Your contributions to this forum are very much appreciated. The fact that you have put much effort into getting a working post for a Thermwood gives the rest of us encouragement to try getting it to work for our own applications.

Everyone's responses to the recent 5 axis post questions have been very informative to me, and I will continue to offer my "best guesses" if I think they will help.

 

Jim teh "this is a great forum"

[crazy^millman]

Yep just the way I feel about it also. To error is human to not try is in my mind not being the person I am. I get great satisfaction out of helping others have since the Boy Scouts. I always look at it this way I can others and others help me and to give back what I gotten from guys here is just all part of it.

 

If you an spefic problems or thing you are working on just post it up. Another thing guys if you by chance are sending me emails and do not zip up your emails I just found out it is getting tagged a virus if a post or something along those lines. If you have sent me something and I have not responed did not figure this out till today. I apoligze if anyone did and I did not get back to you please try me again as a no attachment then we can see about getting the attachment.