Quality Secondary Adjustment

Is there a better way/equipment to adjust the secondary than loosening one or more of the three screws and twisting it by hand. There seems to be too much room for error in setting the secondary angle. I have a 12" HOC dob. I envision a setscrew setup forward of the spider with a rotating sleeve through the spider assembly. Guess I haven't bothered to look at enough telescopes to know any better. Any help?

You should not loosen all three screws and adjust by hand.

You should slightly loosen one screw as you tighten (slightly) the other two.

All screws should remain fairly tight through the whole process.

This will give very precise adjustments.

Alex