Circular Interpolation (Multus)

[zooloader]

Hi Guyz,

I had a mishap the other day. Wrote a prg in IGF with some helical milling. When I looked through the created prg I saw what I thought was an unnecessary line of code. At a glance I thought it was doing the flat bottom in the hole twice, so I deleted one of them.
Oops.
G3 I-30 Z-5 will do a full revolution
G3 I-30 will NOT do a full revolution

I've been milling circles for years and years and find it really annoying that I need to prg two half circles to make a whole one.

If the hole bottom is not critical, I put a Z-0.01 in the line.

Why are these Multus machines backwards when coming forwards??

[budgieW]

If the hole bottom is not critical, I put a Z-0.01 in the line.

Why not just add another line. No big deal.

[zooloader]

No Big Deal ??!!

I have never used a control before (Okuma, Fanuc, Fadal, Cincinnati, Mori Seiki, Matsuura, Fagor), that doesn't interpret G3 I-10, as a full circle.

What I REALLY don't understand is why this Multus can do it with a Z value, but not without it!

Where is the continuity?

[budgieW]

The reason it works with a Z value is because helical milling is an option, You must have this helical option. As for 2D arcs All Okuma lathes work in this way, They always have. So do you have experience with all of these controls on Lathes? My experience is that lathe and mill controllers are generally slightly different, Okuma's included.

Still I don't see it as a big deal. The CAM post or IGF just spit out the correct code.

[zooloader]

True, all my experience has been on mills. Except my last job, on an LU15, which didnt need two halves. I cant say that for sure, because I'm not there anymore, obviously. And you sound like you have more experince than I about it, but in the five years working there on the LU15 and an MC40VB, I dont recall being irritated by such a thing.

Still, if it's an option, can someone tell me why there is two formats on the one machine?
If it can do it helical, why not flat? If something has been switched on, or extra calculations being done, why not for all circular interpolation?

[budgieW]

MC40VB is a Mill and mills work differently to the lathes.

There are 2 formats, 1 for helical cutting as this is an option and the other is for flat circles. There is nothing to be switched on or off. This is just how it is.