about to start...zero help?

[Headsmess]

ha ha...i dont want zero help, i want help with zero...

so, just figured out how to setup the slitsaw feature in the toolbox.

i assume that "flute length" is "thickness" and diameter is, well, diameter :p

all good. it gives me a simulation that looks correct.

so, i have a vh4 vertex 4th axis, thats all calibrated right. not too sure on its exact center height yet...manufacturer says 79, some other site says 80... meh, easy enough to figure out.

im just running a sample code through and have had to reverse motion of the 4th axis, thats cool, its always a bit fuzzy, rotational directions. in this case, its sort of critical. funny. never had to worry about it before...much :D

but where i feel i should get verification before i start destroying cutters and swearing is on the initial zeroing of the tool.

i have a feeling that Z should be the "middle" of the saw, ie, if its 1mm thick, clock to the bottom edge then add 0.5...or subtract...meh.

X is irrelevant for now....

Y...this one could be the critical one... the one currently causing slight confusion... from the bit of code im dry running, i guess that zero is the intersection of cutter and blank/workpiece?

i dont zero the center of the tool with the center of my table? is this right?

cus i cant see any offset other than "safe Z" which in this case is more of a "safe Y" move...

[ArtF]

Hi:


>>so, just figured out how to setup the slitsaw feature in the toolbox.
>>i assume that "flute length" is "thickness" and diameter is, well, diameter :p

  Yes, very true. Luckily the graphic looks correct when you get it right. :)


>>all good. it gives me a simulatio n that looks correct.
>>so, i have a vh4 vertex 4th axis, thats all calibrate d right. not too sure on its exact center height yet...man ufacturer says 79, >>some other site says 80... meh, easy enough to figure out.
>>im just running a sample code through and have had to reverse motion of the 4th axis, thats cool, its always a bit fuzzy, >>rotationa l direction s. in this case, its sort of critical. funny. never had to worry about it before... much Cheesy

    Not unusual, I find almost 50% of 4th axis are reversed from convention, youd never notice typically, gear shaving
is rare. :)

>>but where i feel i should get verificat ion before i start destroyin g cutters and swearing is on the initial zeroing of the tool.
i have a feeling that Z should be the "middle" of the saw, ie, if its 1mm thick, clock to the bottom edge then add 0.5...or subtract. ..meh.

  Yes, exactly the way to zero on a slitsaw or saw type shaper.

>>Xis irrelevan t for now....

  Terms like X, and Y depend on orientation.. But for your saw. You zero so the center of the saw is at zero Z..

X, which is typically the axis the 4th axis points upward on, is zeroed in the center of the blank, the width will make it cut
to either side. The Y, ( side to side .. perpendicular to the 4th axis direction) is zeroed centered to the blank.


Y...this one could be the critical one... the one currently causing slight confusion ... from the bit of code im dry running, i guess that zero is the intersect ion of cutter and blank/workpiece?

>>cus i cant see any offset other than "safe Z" which in this case is more of a "safe Y" move...

  Safe_Z will become safe_y for yout. Watch carefully the simulation, the numbers in the DRO's will show the relative output
coordinates, in situations like slit saws the axis listed may be reversed, but the numbers still show relative positions..

  Alos, run in the air first, be critical about what you see. I recommend zeroign on the balnk properly, then jogging your
Y away by an inch and rezeroing...watch what happens to ensure it all looks correct. (Saves killing the blank. :) )

Art

[Headsmess]

thanks art, though... i sorta went ahead and did it anyway...

no cussing :)

no shattered bits of tool steel...

next time, i shall measure my blank first, rather than just grab whatever is handy and guess it wants 24 teeth... i was right, it did :D give or take half a mm. i had to jog in on the Y about 0.45 to get the depth right.

what sets the travel in the X? i know width sets the blank width, but it seems a bit of overkill, moving the tool about 70mm for a 15 mm blank. it tried hitting my chuck jaws! is it simply due to the diameter of the saw? if so, i live with it...

my only lament now is... bring on the eccentric gear shaving! :) that and the roots blower!

[ArtF]

Looks good as a result. :)

  Normally width is a setting not for blank width, but for the amount of X travel.
The distance you have is necessary so the blank clears before rotation, However,
as of last year you can also select "Reverse Tangent", this is handy for a saw as you
can narrow a lot the width as the saw will pull out all the way between flanks.
  This can save you a lot of distance and time. :)

Art
(Nice work, the involutes look good)...

[MJBoluijt]

My first attempt for making epicycloid gear with slitsaw, at first I have chosen maintain high, the teeth were cut off.
But after that all is ok. Modul 0.5 Z 28



Kind regards

Rien

[ArtF]

Rien:

  Great job. Looks good ( other than the maintain height tests. :) ). Looks
like not a bad epicycloidal from a  slitsaw. With all the bugs and changes from last year
the generation of gears from the 4th axis module seems to be getting near bulletproofed.

  Thx for the example..

Art

[MJBoluijt]

Hi Art,

Yes the form seems good, there was one fault in the file, see a part of it here, no F before the 1000.0
Of course that was easy to change.

Regards,

Rien.

(  No Epilog set )

( Gearotic 2.0 GCode Begins. )
( Object Spur  )
( Job will comprise 1 rotations of the rotary axis.  )
( Tools Used:  )
( Rooting: EndMill2mm Tool #1  )
( Wall Straightening: EndMill2mm Tool #1  )
( Tangential Shave: EndMill2mm Tool #1  )
( Blank size for this gear :  )
( Diam: 15.5543 Thickness: 10.000 )
( SlitSaw Posting. Zero to side of blank.  )
( Root Clearance Begins. )
( Tool change to EndMill2mm )
M6 T1
G43H1
M3 S1750
G0 X23.403  Y0.250  Z0.000  A0.000  
G1 Y-1.572  Z-0.000  1000.0
G1 X-23.403  F3000.00  
G1 Y-1.572  Z-0.093  
G1 X23.403  
G1 Y-1.572  Z0.093  
G1 X-23.403  
G0 Y0.250  Z0.093  
G0 X23.403  
( Root Wall Begins. )
G0 Y0.250  Z0.255  A3.214  
G1 Y-1.563  Z0.255  1000.0
G1 X-23.403  F3000.00  
G1 Y-1.563  Z-0.255  A-3.214  
G1 X23.403  
G0 Y0.250  Z-0.255  
( Tangential Shaving Begins. )
G0 Y0.250  Z0.255  A3.214  
G1 Y-0.777  Z0.255  1000.0
G1 X-23.403  F3000.00  
G0 Y-0.000  Z1.306  A11.846  
G0 Y-0.810  Z1.306  
G1 X23.403  

This is my home made A axis, made with a small harmonic drive.

[ArtF]

Nice Drive:


Sorry about that floating 1000, Ill find that error and kill it, I thought I had it before.. :)

Thx
Art

[Headsmess]

oooooh, tell me more about this harmonic drive...like, how much, from where? :)


and how is it on backlash?

[MJBoluijt]

Look here at regular time
http://www.ebay.com/sch/Electrical-Test ... ?_from=R40 and search for Harmonic Drive.

Sometimes there are cheap ones. Mine was $ 130.00 Take care you buy the Harmonic drive and not the harmonic gear.
No Backlasch  my drive  is about 80mm, 50:1
On a radius of 65 mm you can measure some flex when you make radial force, about 0.01 to 0.03 mm
The cross rollerbearing is strong enough for holding a 80mm 3 jaw chuck

[Headsmess]

yep, did the fleabay check and found a few pop up for under $100. yours looks to be of a lot more compact than what i was seeing...

would really prefer a hollow shaft type but hey... what i saw was more in the region of $400+...ouch. matter of luck/patience i guess.

i always liked the idea of making one by using a toothed belt inside out but noone has yet described how i will make an internal pulley with the correct tooth profile!