[RJoubert]

Hi All,

I desperately need some BobCAD V23 advise. I’ve got a very basic lathe module on trail and I made a simple part to test the tool nose radius comp on a profile that I’ve attached. I'm using a 0.8mm radius tool for roughing and a 0.4mm radius for finishing using system comp on. I’ve found the following problems when machining the part:

1. The 2mm radius is not right, it is a fair bit smaller.
2. The chamfer is bigger, about 2.3mm instead of 2.
3. The corners of the chamfer are rolled over and I need sharp corners.

I have no CNC experience, but the guys on the shop floor, who program all our other work manually, says the code is wrong? I struggle to believe this, it just doesn't make sence that a simple profile can be coded wrong.

Any comments or fixes?

Many thanks

[The Engine Guy]

Hi All,

I desperately need some BobCAD V23 advise. I’ve got a very basic lathe module on trail and I made a simple part to test the tool nose radius comp on a profile that I’ve attached. I'm using a 0.8mm radius tool for roughing and a 0.4mm radius for finishing using system comp on. I’ve found the following problems when machining the part:

1. The 2mm radius is not right, it is a fair bit smaller.
2. The chamfer is bigger, about 2.3mm instead of 2.
3. The corners of the chamfer are rolled over and I need sharp corners.

I have no CNC experience, but the guys on the shop floor, who program all our other work manually, says the code is wrong? I struggle to believe this, it just doesn't make sence that a simple profile can be coded wrong.

Any comments or fixes?

Many thanks

The TNR comp system has always been messed up in BobCAD, the easiest "fix" is to turn all the "comps" off in BobCAD and just set and use the TNR and tool offsets in your machine control, your guys on the shop floor will be correct, listen to them

Regards
Rob
:rainfro::rainfro::rainfro:

.

[RJoubert]

Having looked at various other threads on the topic it seems that BobCAD is actually wrong (well, temperamental) when it comes to profiles and radii. Still struggling to accept this as in my book it is the most basic of requirements for a lathe CAM package.

Will try with the system comp off but the supervisor did say that it still looks dodgy.

[Waynno]

Sorry, Delete