Repair Services

A lot of builders of carved arch top instruments, like mandolins and archtop guitars, use these little Ibex finger planes to carve the tops and backs. (Click the thumbnail images to see larger images.)

I have about four different sizes that I use for carving, and I’ve had to make this modification to a couple of them. I’ve also heard and read of others having trouble with some of the planes not clearing chips properly and becoming clogged. Here is my solution to that problem.

When they are working correctly, these planes will roll up little shavings like these and seldom get clogged. This is the oldest of the ones I have, and it has always worked well. It is the larger of the two in the pictures above.

The smaller one in the pictures above sometimes clogs with shavings because the chips don’t always clear correctly.

When the mouth of the plane clogs, the chips can’t get through and will sometimes tear off and force the user to stop work and manually clean the chips out of the plane. It slows down the carving process and is a distraction.

The problem is this piece. In most planes this is called the cap iron, but these are bronze rather than iron, so I don’t really know what to call them.

Though they look pretty similar in that picture (other than size), there are two important differences. The larger one (the one that works well) is ground and honed on the underside while the smaller one has a rough, cast surface. Also, the larger one has a more gradual curve and sharper edge directing the chips up and out of the plane body while the smaller one has a more blunt edge and steeper curve.

If the cap iron doesn’t fit tightly against the plane iron (blade) there is a chance that chips can get caught in the little gap. Once one catches, the mouth can start to clog.

The first thing I’ll do to improve the smaller one is to hone the bottom surface for a better fit against the plane iron. I’m going to use a “diamond stone” followed by an Arkansas oil stone to hone the edge, and I want to maintain a consistent angle and a flat surface, so I’ll use this little bolt as a honing guide. The threads of the bolt fit in the threaded hole in the piece…

…so I can place the piece flat on the stone and adjust the “guide” so that I’m honing a clean, flat edge at the correct angle. First the diamond stone…

…then the oil stone.

Now both pieces have flat milled surfaces to contact the plane irons.

To re-shape the top surface of the piece I’ll start with a file to get the shape right…

…then use the sharpening stones again followed by a little buffing so the top surface still looks nice and smooth…

…and now has a better curve for deflecting chips, more like the larger one, the one that worked well from the beginning.

Now, with the “cap iron” modified, the smaller plane cleanly shaves curls of wood like it’s larger brother.