Thread Milling

[nzinoz]

Hello Nick,

I understand what you think, but when the spindle rotate, the sharpened ridge turn and do like my disc.

Your picture is good quality, what do you use for a camera?

++
Lionel

Hi Lionel I use a pentax K10 DSLR 18-125 Sigma lens and 70mm extention tubes .
Here is a photo taken from the end of the cutter to show profile for those who would like to grind their own  the tip to tip Diameter  is 7.3mm

[lloydsp]

Lionel,
I understood what you were demonstrating with the disk-like structure.  It makes more sense to look at the entire revolution of the cutter than only one tooth at a time.

It makes me just INSANE that these manufacturers will not make a straight-shank SPTM with a cutter diameter larger than the shank, and make them LONGER!  Most SPTMs will not cut deeper than about 2X to 2.5X their diameters.

That's one reason I'm so happy with my lathe threading bar solution.  I can go to a depth equal to the extension of the tool, and merely reduce the aggressiveness of cut if things start to flex too much.

LLoyd

[nzinoz]

Neat addition to CamBam, so once again, thanks Andy!!

I can envision the tool path but what kind of 'tool' would you use to cut threads like this? 
Happy Fathers Day to all....

Don

Hi Don just found this on Ebay Australia thought you might like to look for something similar
http://www.ebay.com.au/itm/12Pce-06IRA60-Internal-Thread-Insert-8mm-Tool-Holder-Free-Postage-/271003438956?pt=AU_Hardware&hash=item3f19104f6c

[10bulls]

I've just uploaded a new bugfix release:
http://www.cambam.info/ref/plugin.threadingmop

This just contains a small fix where 'Hole diameter must be > tool diameter for spiral drill' was being
incorrectly reported  for external thread milling.

Thanks Jim  for pointing that out.

[Mike F]

Hi,

I seem to be having some trouble loading plugins. I have seven plugins in the 'Plugins' folder yet only three appear. One of the three is the 'CAD Extras' package but only four of the routines in that package are available.

I just downloaded the thread cutting plugin but cannot get that to appear in the list. I am obviously doing something pretty stupid but try as I may, I just cannot seem to load them.

Any ideas?

Mike

[jim1108]

Any plans on adding cutter compensation to this plug-in?

[kvom]

It's quite easy to get the benefits of cutter comp with this Mop.  Just edit g-code file to add a G41 or G42 to the start of the mop code.  The diameter value in the control's tool table will determine the amount of compensation.  Since you generally need to fine tune to the actual diameter of a thread mill, this is useful for gradually increasing the cut depth at the machine without having to generate the g-code.

I personally generate the code using the manufacturer's specified diameter and set the control's diameter to 0.  Once I get a good thread I'll adjust the Mop's value according to the value I end up with in the tool table.

[jim1108]

Other software inserts the G41 and D# in a small linear move before the arc in for the first cut. It then creates the arc from the last point of the linear move. I guess a work around would be this (manually added underlined text below):

%
( UNTITLED )
S1850
G0 G98 G17 G80 G94 G91 G28 Z0
G28 Y0
( FANUC POST 3/1/18 5:42:01 PM )
( T22 : 0.198 .25-28 THREAD MILL )
G20 G90 G64 G40
G0 Z0.125
M9
M5
G0 G91 G28 Z0
G28 Y0
G90
M19
M01
( T22 : 0.198 .25-28 THREAD MILL )
( ACME THREAD MILL )
( THREAD1, .213 HOLE )
( -0.5 )
( 0.0357 )
T22 M6
G0 G90 X0 Y0 M3 S3200
G43 H22 Z.125
M08
( THREAD1 )
G0 Z0.125
X0.0 Y0.0
Z0.0625
G1 F2.0 Z-0.5

G1 G91 G41 D22 X.005 Y-.005 F1.5
X-.005 Y.005
G90

G3 X0.026 Z-0.4821 I0.013 J0.0
X-0.013 Y0.0225 Z-0.4702 I-0.026 J0.0
Y-0.0225 Z-0.4583 I0.013 J-0.0225
X0.026 Y0.0 Z-0.4464 I0.013 J0.0225
X0.0 Z-0.4286 I-0.013 J0.0 G40
G0 Z0.125
M5
M9
G0 G91 G28 Z0
G28 Y0
G90
M19
M30
%

I too use tool makers cut diameter, but I like to account for wear at the machine instead constantly re-generating the code and downloading it.
I am not at the machine to verify, but I dont see why it would not work the way I added the comp move.
I went G91 then back to G90 so it would not matter where the hole location is.

[kvom]

The Mop generates a move in XY to the center of the hole at the start, and when I tested it seemed to work as the preparatory move (at under PathPilot).  I tested only for a single thread per Mop and for an external thread.

[Garyhlucas]

Using CAM you find that you don't need to use G41, G42 very often.  When I programmed by hand I literally used it all the time.  It would be VERY nice if you could tell CamBam to use G41, G42 in MOPs.  I haven't mentioned it before because I have CamBam on the CNC computer so reposting is very easy, but it would be nice to adjust part dimensions without a repost, or use a different tool size.

[jim1108]

I agree.
My programming computer is at the machine, but I have to download the g-code file to the server over WiFi, then upload the code to my machine with a RS232 cable.
When trying to dial in threads, there is a lot of running back and forth. Then, when the thread mill starts to wear and I need to compensate for it, I have to go through the process again. Hand coding is an option, which is how I used to do it, but we try to eliminate as much of that as possible.

[Bob La Londe]

Hi,

I seem to be having some trouble loading plugins. I have seven plugins in the 'Plugins' folder yet only three appear. One of the three is the 'CAD Extras' package but only four of the routines in that package are available.

I just downloaded the thread cutting plugin but cannot get that to appear in the list. I am obviously doing something pretty stupid but try as I may, I just cannot seem to load them.

Any ideas?

Mike

Mike, Sorry nobody responded to this sooner.  Anyway, this might help.  Since I switched to W10 (never used 7 or 8 for CamBam)  I've had to unblock every single plugin before it will show up.  You might need to be logged in as admin or in admin mode to see it. 

[Mike F]

Hi Bob,

I don't get the same as you. Attached is the screenshot of the properties of my 'CamBam plus 1.0' folder. It shows files as read-only but when I try to change it, the check in the checkbox disappears but returns each time I re-open the properties. I am using the computer as administrator so that should not be the problem.

I don't see any reference to files being blocked.

Mike

[Bob La Londe]

Sounds like it might need to be posted as a help query in the "Other Software" section.  It still sounds like a Windows problem to me. 

[dh42]

Hello

I don't see any reference to files being blocked.

Maybe you have to select the file only as on Bob's picture, not the whole folder ?

http://www.cambam.co.uk/forum/index.php?topic=6294.0

++
David