Reliable old file now cutting features slightly big...

[badornato]

It's as though the machine thinks the bit is smaller than it really is. Madcam creates the code...Is there something within the bot software that is scaling it up? I checked the cutter size in shopbot (and on the machine) and it's correct. One recent change is that I loaded cam on a new laptop/new Rhino install and the first file off started the issue. Now even my old files off old the computer do the same thing.

It's awfully consistant to be mechanical...

This is driving me crazy. Please help me.

[Brady Watson]

Make sure your unit values are correct. Put a tape measure down on the table and check distances.

-B

[srwtlc]

Brant,

The cutter size in SB3 will have no effect on your files generated from a Cam program. That's for the canned routines in SB3. Make sure that when you load a file in SB3 that the proportion for x,y, and z are 1,1,1 in the fill in sheet (they should be as default).

I'm not familiar with Mad Cam, but I would suspect that it might possibly be adding some cutter compensation (offset) to your files at the time of tool path generation

Some setting that got changed inadvertently? Maybe in your tool database?

[badornato]

Thanks for the thoughts...
Brady: I have measured distances as cut vs the model in cad and they seem to be scaled up by a discrete factor (although not a value that indicates one bit size vs another).

Scott: I figured that (SB doesn't care about the bit size) as I have files that include a bit change where I don't have any code telling SB that the bit size changed. Just a new file reference where I changed the size in CAM.
I'll check the proportion as that seem likely (although why it would change...?) MadCam does create offset, but it makes sense and is measureable both in CAD/CAM and when looking at the values in the code.

What kills me is that it's doing it with files I've used many times before...

[Brady Watson]

"have measured distances as cut vs the model in cad and they seem to be scaled up by a discrete factor"

Check your unit values and make sure they are correct!

-B

[badornato]

I'll check them. I see that they are related to the number of steps per in. I get X Y and Z...Do you know what A and B are? I noticed that the A value (916.7324) is not set to the default (733.386) on the software I have here in the office (not the one running the bot).

Also, Seems like the defaults would correlate to a default stepper motor. Should I go w/ defaults or something I should know about my motor?

Thanks! B

[srwtlc]

Are you using a different computer and a new install of SB3 than what you were before? You did mentioned a new laptop.

Like Brady stated, check those unit values! Make sure it's moving what you tell it to. I like to clamp a block to the rail tight against the carriage, zero out that axis, give it a move of 1", 2", 3"...6" and check it with a caliper (my caliper is a 6") and then back to zero to see if the block get pushed any at all.

[srwtlc]

Oops, you posted while I was typing.

Try this thread and see if the chart helps at all. What do you have for motors and pinions?

[fleinbach]

Are you sure the bit is the right size. did you actually measure it? I bought a 1/2 inch bit localy once (can't remember exactly the name of it) and after cutting a file that came out wrong I found that the bit actual cut width was around 15/32