I recently picked up a LN 4 ½ smoothing plane and I’m looking to get a larger plane for flattening, either a 6 or 7. I noticed those two as well as the 5 ½ all share the same size blade. This made me wonder about the purpose or capabilities of these particular planes. We all know the longer planes are better for flattening and that makes a 7 better than a 4 ½ for the task. Now seeing that they all share the same blade, and ignoring the weight difference, would a 7 work just as well as a 4 ½ for smoothing?
The point I’m trying to get at here is a buying strategy for planes. Would It be best to go ahead with the 7, then get an addition blade(s) and chipbreaker(s) and put a higher bevel on the blade? This way it could be put in either the 4 ½ or the 7. What about a higher angle frog for tough grain? I assume a higher angle bevel or frog would be necessary for tough grain, but not both? Are the frogs interchangeable between the 4 ½, 5 ½, 6 and 7? When would I want the 5 ½ instead of the 4 ½? When would I want the 6 instead of the 7?
My adventure into hand planes is just beginning and I want to make sure I have a good understanding of the planes before I rush off and pick something else up. Current block/bench planes right now, all LN, AM block plane, LAJ plane and the 4 ½.
Dennis
Edit: got to love the formatting it does with the fractions!