Checking for twist

[merlin1968]

I have a part that they are wanting to check for twist, the part measures 72.5" long. I need to find a repeatable way to fixture and check this part, without changing the free state characteristics of the part. Up for suggestion. We have a B&S with a TP-200.

20190807_124103.jpg

[Matthew D. Hoedeman]

a square bolted to the table to 'datum' a corner, and a straight edge at the other end to stop rotation, push the part against the straight edge at one end and tuck it into the corner of the square.

[merlin1968]

If I had access to a romer arm with scanning capabilities would that be better being non contact

[Ego Murphy]

Before you even begin, nail down the format and units for the vague word "twist".

Is there a print dimension, and is it expressed in inches/mm/decimal degrees/degrees-minutes-seconds/thumb-sized gaps? Is there a tolerance?

If no print dimension, ask the people wanting the data what format they understand.

[merlin1968]

1 degree per foot, max 7 degrees per full length

[Schlag]

You may need some kind of fixture to hold this thing ??? Really you need to check flatness and straightness of a line to come close to what you are looking for ? That looks like an extruded part we made at one time except in plastic ? Or is it an aluminum extrusion and just painted ?