I had recently acquired a barely used planer from Sears. It was one of those deals where the price was right and I couldn’t pass it up.
When I first brought it home, I fired it up and ran a few boards through it. It seemed to work great, but I didn’t need it right away, so I stored it under the bench. Let me say right here that when Sears calls this a “benchtop” planer, that’s an outright lie. This monster is heavy. I’ve got to build a stand for it one of these days. But I’m getting sidetracked.
While I was in the process of building the project mentioned in this previous post (where I injured my thumb on the table saw), I needed to plane some 3/4″ curly maple boards down to 1/2″ thickness. (Yes, it broke my heart to see 1/4″ of those boards go to waste as chips.) As I was planing, I noticed that there was a wide, shallow groove along one edge of the boards along the entire length. Since the two boards I was planing were cut from longer stock, I thought that the boards were rough-planed that way and that’s how I brought them home. A couple of shallow passes later it dawned on me that the groove wasn’t going away. “Great,” I thought. I was going to have to tear down this planer to see what was going on.
Fortunately, this planer is designed to make it fairly easy to get to the cutterhead. A few screws remove the dust shroud to gain access to the knives. As I rotated the cutterhead around, I couldn’t believe what I saw. The gib holding the knife in place was bent outwards and the remaining cavity between it and the knife was crammed full of chips. You can see what I mean in the drawing at right. (I tried to hightlight the area in red.) The item labeled ’65’ is the gib. Item ’64’ is the knife. (Item ’60’ is the cutterhead.) Now, what to do?
Figuring that the worst-case scenario was ordering a new gib, I attempted to straighten it. I clamped the bent area in heavy-duty vise and torqued it as far as I could go. That took care of the majority of the bend. Then some carefully placed taps on the leading edge of the gib with a wood block and hammer took care of the rest. Some minor filing was all it took to get a smooth, straight edge. I re-installed the blade and gib and ran a few boards through it. No sign of a “groove.” I was relieved and glad that I was able to repair it.
But the question remains…what caused the gib to bend in the first place? It’s possible that it was like that when I first bought it. But the mystery remains. When I talk to the other guys in our shop, no one can come up with a plausible explanation. Very strange. If you’ve got any thoughts, leave a comment here.