wrote in message
...

Ideally, the center of mass of the boat should be just ahead
of the axles, just enough to give you the tongue weight you're shooting
for. All else being equal/unchanged increasing the tongue length will
increase tongue weight by the amount of extra material in the tongue.

That's true, the tongue weight will increase by the weight of the
added material. (Actually, as Steven pointed out, some of that
added weight will also be supported by the whels.) But most
of it is nearer to the ball, and most will be supported there.

BUT, the weight of the added material is very small
and I believe can essentially be forgotten about. In our
example, an extra 3 feet of tonge would be maybe 20 lbs
of material. When we're looking for a tongue weight of
400#s, thats nominal.

What is ALSO true is that that longer tongue (all else
staying the same) moves the end of the tongue farther
away from the pivot point (axel). A longer arm (tongue)
gives more leverage. It would be easier to lift that
tongue off the ground or up off the ball. There would
be "less tonge weight".