I have wanted to make an adjustable height support to hold the strong back. There are times when you don't want to bend over, for example while installing a strip, and others when you want to be able to keep your hands in a low relaxed position, for example while sanding.

I usually end up with the strongback at the 35 to 40 inch height. It depends on the particular design for how ideally the height works out.

In classes where there may be a wide range of sizes between students I will sometimes use riser blocks to adjust the working height.

Obviously, this is not an interna-vs-external-strongback issue, but what-is-good-height issue and like I said, it depends on what part of the project you are currently doing.

Ive thought about mounting my work on a scissor lift so I can adjust it up and down, but I haven't worked out a good solution yet. Until then I should really get an adjustable height rolling stool for lower work.