A Point About Trammel Points: Sheet Metal Hack

Trammel points have their place in the shop. I'm not going to actually use them for what is normally their intended purpose, but I WILL give a description of a job they can be used for in a pinch. The whole point of the video is to show how to make multiple marks on multiple pieces of duct halves without using a folding rule, circumference rule or tape measure. It's all for speed and efficiency of movement in the process of laying out multiple pieces of duct halves.
For their intended purpose, trammel points are unbeatable. That function is laying out radius fittings of any size, but especially they shine in the large radius department. You know the ones....the ones that the standard dividers won't stretch out far enough to create the arc. Another layout they are perfect for is for the fabrication of round chimney caps.
Today, two home made trammels are shown then a much shorter version is shown for a different intended purpose and that is repetitive motions of a specific measurement while laying out multiple sections of duct of the same dimension.
Enjoy....