Recently, I bought a semi-professional #7 jointer plane, which doesn't mean much by my country standards, since we get Chinese rip-offs that are sold under famous brand names (and prices). Nevertheless, it was the best I could get and afford.
Naturally, this jointer needs a lot of work before it can be used. One of the sides is at a perfect 90° to the sole, however, the other one is at about 87° to the sole (meaning that the sides are not parallel). If I'll ever have to use it on shooting board, I'll use the good side.
However, the big problem is that the sole is nowhere near flat. The shape is concave along the length, and somewhat across too. I have a calibrated granite block, so I placed some 60 grit sandpaper on it, crossed the sole with marker, and then started "planing". After 5 hours (not exaggerating) of sanding, I gave up, because I'm nowhere even close to flattening it - there's just way too much material to remove.
Here are the photos of the progress of flattening, taken about once every hour.
As you can see, at first, the progress was good, but as I went on, the contact surface increased, meaning there's more and more steel to grind. By the end, I realized this is going to take forever, likely longer than that.
Even though the marker pattern indicates that the ends and the sides of the sole have been flattened, placing the jointer against flat granite revealed that the ends are still way too high. I have no idea why the sandpaper didn't fix the ends - maybe it isn't pressed against granite well enough, springs up, and follows the concave shape of the sole?
Anyway, I'm looking for an alternative way to flatten that sole, because doing it traditionally is neither accurate, nor fast enough. My arms are killing me already from all that grinding. I would appreciate any suggestions you guys might have...