G51 Scaling: how to?

[Donkey Hotey]

I looked through my Haas manual last night and could not find a single example of G51 scaling. What I can't find is the syntax. I found another reference to it in here and it looks like G51 P0.5 where P0.5 = 50% scaling for all dimensions after that.

My question is: can I control X, Y and Z independently?

Here's what I want to do:

I have a logo that I want to store as a signature. I want to store that logo in the machine as a program, at a standard size (say 1" for ease of dimensioning). When I'm running parts that will be logo'd, I'd setup a local work offset for the logo's origin and set Z as the top of that surface.

At the end of a program, I'd add the logo with a subprogram-call with G51 scaling and G68 rotation. The reason I want independent scaling is so I can scale X and Y but leave the Z engraving depth the same (0.010").

The only alternative I can think of is to subtract the engraving depth (0.010") from the work offset Z, then engrave down to zero. In that case, the Z depth scaling wouldn't matter.

Any suggestions?

[Geof]

I played with scaling quite a while back and I think I came to the same conclusion; move the Z to counteract the scaling.

The application was almost identical to yours; engraving a tradename on a part.

Now it is done using a macro written by one of my guys; nice thing having employees, it reduces the need to think.

[Donkey Hotey]

It's always good to hear when my noob level of experience comes to the same conclusion as yours, Geof.

I thought I was going to always reprogram that logo in each part. That seemed like a waste. I also couldn't figure out a good way to scale it or rotate it in Solidworks. The subprogram idea with scaling and rotation is so obvious that I don't know why it didn't dawn on me sooner. I just need to get a standard 1" logo in there so the scaling is easy.

Thanks again,

[BobWarfield]

Old thread, but it ranks high on Google if you go looking for G51 examples, so I will comment.

On Haas, you can't set scaling for each axis independently.

I found that out via this Haas slide show which has the syntax:

http://tinyurl.com/haasg51

Cheers,

BW

[Mr. Technical]

Bob,

As one would expect, you beat me to your own source of information!

I just watched the Haas Powerpoint presentation last night, as linked to from your thoroughly entertaining and informative CNC Cookbook blog. As I was reading the earlier posts, I was thinking 'Hey, I may be able to actually help someone', but alas my hopes were dashed! Keep up the good work on the blog!

Ian

[helocat]

OK old thread yes, but great info. G51 would be an asset to me as well for the logo placement. So for z to maintain a correct depth of cut, just edit the tool height offset?

Mark

[Geof]

Originally Posted by helocat OK old thread yes, but great info. G51 would be an asset to me as well for the logo placement. So for z to maintain a correct depth of cut, just edit the tool height offset? Mark

I just had an idea (where is the light bulb smiley?). Don't edit the height offset, use G10 or G52; G10 L1 (or L11) can be used to enter a wear value for the tool length and G52 Zn can be used to give a Z shift of n. The advantage to doing it this way is that you can cancel both back to zero after you have done the engraving.