Is there any easy way to align 4th axis and tailstock on the T-slot plate of my CNC perfectly without touch-probing and releasing and slightly pushing and fastening and touch-probing again for hours?
The alternative would of cause be to touch-probe left+right side of the stock at the chuck and at the tail-end and calculate a G68 rotation for my work coordinate system to match the orientation of the 4th axis in the XY plane.
Test indicator, this is where understanding indication and machine fixturing starts to become required.
It depends what you call easy. I don’t like indicating fixtures myself. It is tedious work. There are some techniques that make it somewhat easier.
I could add a spoil-board and mill 2 perfectly placed pockets (+1 hole for the protruding chuck jaws to rotate through) to place 4th axis and tail stock into. As they are milled, the sides are perfectly aligned with the X axis.
@Marcus_Wolschon You can go that route. I believe that method is called palletizing? Your milled spoil board is the pallet that your work rests on, and is registered with. It is expensive in materials compared to just indicating though.
What would I do with indicating the fixture? The tailstock will never be in the same location twice (depending on the length of the material). This is the type of 4th axis I have (with a larger chuck):
Indicate the Chuck in with a ground dowel with centers. Once that’s done setup your tailstock on centers and indicate your dowel the full length. Dowel should be similar in length to part you are wanting to setup.
I’m not a machinist. I don’t get what you are trying to say.
What do you mean with “indicate the chuck in”?
Mount a “dovel with centers” in the chuck and make sure it’s perfectly centered by rotating it and checking with a dial indicator?
Setup on centers = dovel center and tip of the tailstock shall match. sure.
What do you mean with “indicate your dowel the full length”? I know dovels to not have much length to begin with and that length is fully gripped by the chucks at that point.
All that only seems to make sure that chuck and tailstock are aligned to each other but not that things are parallel to the X axis in Y and in Z dimension.
Yes traverse down the length of the dowel to make sure your travel and part are parallel. Indicator will show you how close or far out the part to travel is.
I get that you are talking abot a different kind of dovel. I know these:
I’m not sure I’m capable to align anything with my hand to 1/100mm or less. What I’d to would be to losely mount the 4th axis on 1 bolt only. Free to pivot. Mount a steel rod in the spindle. Touch the stock near the chuck and run the rod down the length. Pushing the material sideways until it’s parallel with X and the 4th axis thus aligned. Then mount clamps to keep things where they are while fastening all mounting bolts tightly.
http://assets.rockler.com/media/catalog/product/cache/1/image/720x720/9df78eab33525d08d6e5fb8d27136e95/2/7/27179-01-1000.jpg
@Marcus_Wolschon well one of the tricks is to not use your hands. You hit stuff to align it. That’s just how it is done. It is all in the lick you give it. That’s why every machinist has a hammer. I kid you not. Tapping can be rather precise.