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View Full Version : Help please - the wedge sticks on my molding plane



Frederick Skelly
04-10-2015, 11:17 AM
Hi folks. I finished my first shopmade "round" molding plane (pics are coming, honest). It works well. The only beef I have is with the wedge. I have to tap it down more than Id like to keep the cutter at the right depth. The, as a result, its a real bear to remove the wedge when I need to adjust the cutter or sharpen it. The antique molders and dados I have all hold firmly but release easily with a rubber mallet applied to the heel. So Im guessing the wedge needs to be tuned a bit? But Im unsure what else I can do.

Both contacting surfaces on the wedge are smooth and flat. The throat is flat. The throat was finished with danish oil. (Probably shouldnt have finished that but didnt realize it till later). Anyone have an idea what I can do to make this wedge grip better AND release better?

Thank you!
Fred

Jim Koepke
04-10-2015, 12:48 PM
Both contacting surfaces on the wedge are smooth and flat. The throat is flat.

One of my molding planes was giving me a problem like yours. It turns out it wasn't the contacting surfaces. There was a bulge in the sides of the wedge that was getting stuck in the plane body.

Not sure if the danish oil could be a cause of sticking. Maybe a little wax on the wedge could help.

jtk

Tom McMahon
04-10-2015, 3:10 PM
If your blade is tapered from the tip you can tap the blade down and take the pressure off the wedge.

Steve Voigt
04-10-2015, 3:47 PM
I would not wax the wedge. If you get any wax at all on the top or bottom of the wedge, it will not hold.

First, insert the wedge without the blade, and make sure it's not binding on the sides, as Jim said.

Second, put some fine (like 220) sandpaper on a flat surface and lightly abrade the top face (the face that bears against the front of the wedge mortise) of the wedge, so you have a clean surface. Now insert the blade, tap the wedge in lightly, then remove and inspect. If you don't see any marks, try again, a little harder. The idea is to read the marks that the front of the wedge mortise is imprinting onto the wedge. My suspicion is that your angle is a bit off and the mortise is gripping only at the top or bottom. You don't need to see marks the entire length of the mortise, but you need them at the top and bottom. If you are only getting marks on one of those, scrape or plane the marks away and repeat until it looks right.

Third, mark the un-beveled side of the blade with a dry erase marker, insert the blade and wedge, and tap the wedge in firmly. Remove and inspect. You want the marker to imprint the wedge in the mortise area, and at the bottom of the wedge. It doesn't have to imprint the whole wedge; you just need two good points of contact. You don't need to mark up the blade above where it contacts the wedge mortise. Anyway, scrape or plane away the marker residue and repeat until the wedge is right.

You may need to go back to step two after you do step three. Take it slow and try to remove as little material as possible with each pass.

Frederick Skelly
04-10-2015, 6:27 PM
Thanks guys! I really appreciate the help. I'll give these a try and let you know how it goes.

David Dalzell
04-11-2015, 5:56 AM
I have never built a molding plane but I have built many block, jack, jointer wood planes. It is important, with these planes to have the right degree of wedge on the wedge. In other words the angle between the bottom of the wedge and the top. I generally use 7 degrees. More and the wedge doesn't want to stay in place; less and it has to be driven in deep and thus is hard to loosen.