Good Morning! I'm new to using CAD models. I only used them in class. I created a manual plane, line, point alignment to make the model aligned with the machine. The problem I'm having is when I change my alignment or workplane, my points are no longer aligned with my model. They are offset and mess up my dimensions. Do I need to continually redo the manual alignment to keep everything where it should be or am I missing something else? Thanks in advance!
I don't do manual alignments. If I was doing a manual alignment, I would always fallow up with a DCC alignment right afterwards. Measure the same features just in DCC and make a DCC alignment. When you start dimensioning, recall that same DCC alignment or If there are specific datum callouts, align to those and do your dimensioning. Hope I said this ok. My words make sense in my head. They don't always make sense when i write them down.
Are you making sure to use program mode to select the hit points on the model when making the manual features? Other than that, I'd do like
ThePudds said and use a DCC alignment with auto features. That way you can select them directly from the model so the machine will correlate the two.
There are other ways like read point alignments. Stick with what your doing. Once you nail this then look into other options. ...... Yep, you need to take the points ON THE MODEL. Or , you can force them there by changing nominals. Correct, you must have some type of alignment for the machine to finds the part
First, lets address your original question. Before you even begin programming, you should "square" your model in PC DMIS' "Graphic Display Window" to how it will be sitting on your CMM in real life. You'll notice that once you import your CAD, the trihedron will be facing a particular direction. If you want to change that, you can do one of two things..... 1) You could move the origin/orientation of the origin in the CAD's native software BEFORE you import it into PC DMIS. That way, all you have to do is import it and BOOM comes on your screen the way you need it. This is the easiest way for beginners. 2) Import your CAD into PCD. Then, go into "Operation/Graphic Display Window/Transform". Use this window to translate/rotate your model. Hit "Apply + OK" when you're done. Now your model will be the correct way on your screen and you can begin programming. In training at Hexagon, you didn't have to worry about this because the models they used all had the model already squared up from solidworks.
Regarding finding the part with no manual alignment, there are many ways to do this. You're right, you do have to tell the machine where the part is..but that doesn't have to be accomplished with a manually probed alignment! In my experience, I have found that the more I allow people to manually probe stuff, the more likely I am to have stuff break/have bad things happen. External fixture alignments are used at my company. My operators don't have to touch the jogbox for 80% of my programs. They load the part onto a fixture and it goes on it's own. People also use "readpoint" alignments, they're fairly easy to set up and are a good starting points for beginners to make their programs more advanced.
Without a manual alignment, how does the machine know where the part is?
For what I do when programming, I use Readpoints and Readpoint alignments. I move the origin myself by doing what
DAN_M says above, type READPOINT into my code, auto populates, then I change my theos to 0,0,0, then I align just the read point to X,Y,Z origin. Which changes the machine 0,0,0 to where your probe is located. I generally use a circle when doing this because then i can measure the circle from the readpoint, align to the circle and go from there realigning when i need throughout the program. Sometimes a simple ABC_Align works great. Some of our weldments that we do have such big tolerances and they move so much that i have to align to every little feature just to find the next. If I'm working on a machined part an ABC_Align 9 times out of 10 works every time. Very seldom on machined parts do I have to align to specific features to find the next.
I think I'm going to have to start a new program since I wasn't always working in program mode. As my program is now, everything works perfectly fine and all dimensions are good until I change from A0B0 to A52.5B90. Once I do that, I can't select points from the model. It either shows them in incorrect placement, like hits going through the circle, or if it looks correct, when I execute the circle, it crashes into my part.
If the orietation of the CAD is correct. Change the features nominals used in the manual alignment. Those noimnals are in MACHINE coordinates and they need to be in relation to the TRIHEDRON that is on the cad when its imported.
