Do away with manual alignments - use Readpoint

I do too many one off's / prototype work , don't mind doing manual aligments . I still add a DCC aligment after to take out the human eliment.

I'm pretty much in the same boat. Not much in the way of fixtures, or decent "fixturing" components at the present time.

It's actually possible to go straight to DCC alignment and also not have any fixtures at all, you just have to be a little creative and use a few functions as they were not intended lol.
I have ours set up so you just need to place the part generally in the center of the table (in the orientation shown on the drawing of it), but it doesn't matter if its crooked or not square at all.
Next the probe just kicks to A45B0 and 0.25 inches from the table and scans until it, for lack of a better term, runs into the part. (Although I recommend lowering the speed to measuring). You can then easily write an algorithm for it to figure out where your part is and align itself. This will add time to your measuring, but if your smart about it should only be around 15-30 seconds at most.
This is especially helpful when you have 100 different parts and would need to disassemble fixtures and rebuild them everytime.

I've only been programming for about 1 month, Level 1 training only. What is the best alignment option if I always use the same fixture bolted to the CMM? I don't have a CAD model of my part. I check axel shafts so manual align is a cyl & a plane. I don't want to have to do a manual align every time & I not going to level 2 training till later this year.

Look for threads that discuss readpoints. Using a readpoint, the operator merely has to move the probe to a certain feature. You align the readpoint as 0,0,0 and then fo straight into the DCC alginment.

You also could write a program that aligns the fixture. Save that alignment as an external alignment.
Then, recall that alignment at the beginning of your part programs. Then run a DCC alignment on the part.
Works like a charm!

Readpoint is all fun and games till you try to run the program on the other side of a dual arm CMM.
Wish I would of thought about that about 10 programs earlier!!
Had to put manual alignments in again....

We use "yes/No" comments at the start of a program, asking the operator if a manual alignment is needed. This leaves it up to the operator if one is needed or not.

Using MeasureMax software I have used a datum from a Rayco plate to start programs with and I have also used the calabration sphere as my starting xyz origin. Just recall datums and go. Now I am back (gone from programming for 8 years) and am struggeling with alignment using PC-DMIS Cad++.

I hear a lot of conflicting ideas on how one should go about using read points, which leads to much confusion on which technique is correct. We use read points at my place of work and always used with CAD, and of course the read point, manual alignment or all in DCC mode. But, can anyone of you PC Dmis Gurus tell me with any degree of accuracy if read points are possible without the use of CAD and if so how would someone go about doing such?

Sometimes we get old parts with no CAD and a program has to be made and I feel that read point alignment could be very effective if it is possible. I only know if the use of such with CAD but desire to use it without CAD. So, if anyone out there could please give me some DEFINITIVE answer. I do not mean to come across so skeptical but it seems that every CMM person I have asked on different sites cannot agree on the "One best way" to use the read point without CAD. Mostly what I prefer is to G+CTL to set a readpoint then 0 out X, Y, and Z as origin (in CAD), usually inside a circle with find center on. Then I do create a plan using Auto Plane (radial), and a small line in X or Y to rotate to.....then the DCC Alignment to the CAD models FCF & Datum call-outs... So to be a little more definitive myself... can I do read points as explained above and if so would I create the read point prior to going into DCC mode or in DCC mode, which means my manual alignment would also be in DCC mode......Any info would be helpful and appreciated...

CMMGUY13

A readpoint is just a tool in your toolbox. There's no 'right' way to use it. It is intended as a positioning tool. I can tell you that I use readpoints to reduce operator input. Rather than a rough plane for Z and a rough hole for XY position, a readpoint can get you close enough to go to DCC and then inspect automatically those features which might have first been done manually. Voila, you just saved your CMM guy from manually taking 6-10 more hits on every single part he inspects. Your end goal is to measure the features necessary for the final print alignments as soon as possible, and do so with a stable alignment. How you use readpoints to get there is up to you.

How do you make a readpoint without using CAD? we use mostly CAD and do read points but does anyone know if it is possible to do read points without CAD...If so how?

How do you make a readpoint without using CAD? we use mostly CAD and do read points but does anyone know if it is possible to do read points without CAD...If so how?

1) plan your inspection method

2) plan how you will setup your part.

3) plan where you want the probe to begin

4) move probe to beginning point and press CTRL-G

5) write your program from here