Incorrect size Irons

[Richard Gillespie]

I have two wood planes that have the wrong iron in them. One, a 16" Jack, the mouth opening is 2" and the iron and wedge are 1-3/4" wide. The wedge is so narrow it won't engage the plane body to secure the iron. The other plane is a coffin smoother with a 2-1/4" mouth. It came to me with a 2" wide toothed blade that I think is used for veneering.

When looking for replacement irons for these two planes does the iron need to be the same width as the mouth or slightly smaller?

[Jim Reed]

Most woodies I see like that have about 1/8" to 1/16" wiggle room on each side for adjustment.