Making a little slider block out of .250 thick walnut. The final version of this part will be acetal (Delrin).

Cut, sanded to length, and deburred all the tubing pieces. The little short pieces are only needed because the wall thickness of this tubing is .015 whereas the final wall thickness needs to be ~.032. The little pieces will be soldered inside the ends of the longer ones.

Each size of this brass tubing is a slip fit inside the next higher size. To prevent these little end tubes from sliding around while soldering, I used the center punch to peen outward at three positions around the perimeter.