I love using wooden planes. I don’t think they’re in any way better than other types of planes. The wood certainly doesn’t know if it was planed by a wooden or metal plane. I just prefer the feel and action of wooden planes. As a result of using them and demonstrating using them through the blog and podcast, I receive a lot of questions about using them and getting old wooden planes to work well.
The first thing to check with a problem plane is that the iron is sharp. The second thing to check with a problem plane is that the iron is sharp. Assuming that the plane iron is adequately sharp, the most frequent problem that new users of wooden planes encounter are that the planes either don’t cut at all or when adjusted for a deeper cut they will only take thick cuts, chatter, skip and jam. Mouth clogging is also a frequently encountered issue. In my experience with wooden planes, these problems are almost always caused by two or three issues that the planes might have. I suggest addressing one of these issues at a time, in the order they are listed, and checking the plane’s performance after addressing each. If you are having problems getting a wooden plane to work well, I’m betting that one (or all) of these adjustments will solve your plane’s issues.
Flattening the Sole
Usually, the sole of an old wooden plane is slightly concave in profile. This causes the plane to either not cut at all when the iron is set to take a light cut (because the concavity lifts the iron off the work), or to dig in and chatter because the iron has to be extended too far out in order to make contact with the board. So flattening the sole would be my first attempt at a fix.
With a jack plane sole flatness typically isn’t an issue. Jack planes are usually set up to take a thick cut. I have never personally bothered to flatten the sole of a jack plane, though I’m not going to tell you not to if you really want to. With a try plane, smooth plane, or joinery plane, however, you want the sole to be relatively flat in order to do fine, accurate work.
Planing the sole with another plane is one way to get there. If you already have a well tuned metal (or wooden) plane, simply planing the sole flat is probably the fastest and easiest method. With the iron backed off but tightly wedged in place, you put the plane in the bench vise, sole up, and plane the sole flat. Take very fine cuts and check the sole frequently with a good straight edge and a pair of winding sticks. The process is no different than flattening the face of any board. When you’re done, you want the sole to be flat and free of twist.
Lapping the sole with sandpaper attached to a flat substrate is another way to make it flat. Be careful with this method though. Lapping a long plane can quickly turn it into a convex soled nightmare if you use too much pressure or too aggressive of a paper. If you make the sole convex, it is a condition that is much harder to correct.
I recommend not going coarser than 220 grit paper. It will go slower, but that just means that things won’t go wonky as fast. Draw lines about 1/4″ apart side to side across the sole of the plane. This will help gauge progress. Make sure your substrate is flat and well supported. Brush the dust off the paper frequently to keep it cutting as evenly as possible, and change the paper before you think you need to. Lapping causes the paper to dull fastest in the middle because the middle area is always in contact with the plane. When the paper dulls in the middle faster, the outside edges of the paper will cut faster than the middle, resulting in more material being removed from the outside edges of the plane than the center. If the plane is currently concave, this can easily be mistaken as removing concavity because in a concave soled plane, the outside edges will obviously be sanded down first. So don’t just rely on the pattern of the pencil marks on the sole to gauge your progress. Check the sole often with a straight edge and winding sticks to make sure you don’t go past flat and make the sole convex.
Use light pressure when lapping. Just enough to move the plane. Believe it or not, if you use too much pressure, you can flex a concave sole slightly back into flat while lapping, so you will think you are making progress when in fact you are simply flexing the concavity out. Then when you check with a straight edge, it will still be concave and you’ll be banging your head against the wall trying to figure out why. The weight of the plane should provide the majority of the downward pressure. You just want to move the plane back and fourth, without putting any significant downward pressure on it. And remember to keep the iron tightly wedged in the plane while lapping to make sure the plane is under wedge tension. Just back it off so it doesn’t project out the mouth. This provides the most accurate surface from lapping.
Re-bed the Iron
In these old planes, seasonal movement over the last 150 years sometimes causes the bed to take on a slightly humped profile. This makes a wooden plane all but unusable. I’ve found this to be a very common problem with these old wooden planes. Addressing this issue usually makes a drastic and immediate difference in how a wooden plane works.
This might seem like a difficult task, but it’s really not. It’s just slow, tedious and time consuming. But I’ve found that almost 9 out of 10 planes have a bedding issue when they are experiencing chatter and issues with not cutting or digging in but not producing a nice smooth cut. To check the bedding, put the iron assembly in the plane and wedge it tight. Turn the plane over and try to insert a thin feeler gauge between the iron and the bed (a thin piece of paper will work too). You should not be able to insert the feeler gauge past the end of the iron’s bevel. If you can, then it means that the iron is not well supported behind the cutting edge and that it is likely flexing in use. This causes bad chatter, skipping and planes that will either not cut when set thin, or will dig in and chatter when set just a hair deeper than when they were not cutting.
Re-bedding the iron is fairly easy, and much easier to see done than describe, so I strongly suggest you check out the podcast I did on re-bedding the plane iron in a wooden plane. All you need is a candle and a file. Basically you soot the bevel side of the iron by holding it in the candle flame. Then put it in the plane, being careful not to disturb the soot. Wedge it tight, then tap the iron a couple times to advance it slightly. Then remove it from the plane carefully and see where the bed of the plane has had soot transferred to it. This is where the iron is contacting the bed. File away the sooted spots and repeat until the iron makes good contact all along the bed right at the contact point of the bottom of the iron. When done, you should no longer be able to get the feeler gauge under the iron.
Address Wedge Issues
As long as the wedge is fitting well, it’s probably fine, unless its tips are catching shavings and causing the mouth to clog in use. Many times, the wedge has shrunk narrower than the mortise, so the tips of the wedge are not in contact with the sides of the wedge abutments. You can see if this is the case by looking into the mouth from the sole of the plane and observing the tips of the wedge. You might need a flashlight to do this. If the wedge has shrunk, you’ll see a small space between the tips of the wedge and the sides of the wedge abutments. These spaces can trap shavings, especially when the plane is skewed, because skewing directs the shaving to the sides of the abutments. To fix this problem, you can glue on a thin piece to either side of the wedge and reshape the wedge to tightly fit the sides of the abutments or you can make a new wedge. Here’s a post I did several years ago on making a new wedge.
Thoughts on Mouth Patches
Some people advocate adding a patch to the sole of a wooden plane to close up the mouth. I’ve never bothered to do this, although I have seen some examples of old planes where this was done. The thing is, I don’t think these old planes ever had or were intended to have really tight mouths. I have seen (and purchased) old planes that were virtually unused and the mouths were not what would be considered tight today by any means. I’ve not encountered a domestic hardwood where I felt a plane with a tighter mouth would have been helpful either. I think a really tight mouth in a wooden plane can lead to clogging do the the wear part of the throat closing in on the shaving. Perhaps a really tight mouth would be helpful in a smoother designed to tackle really nasty exotic hardwoods with convoluded grain. I’ll never know as I don’t use these woods. For a jack or try plane a mouth patch would be a waste of time in my opinion. Even for smoothing, I’ve never found a wood [that I commonly use] that I couldn’t handle with my 55 degree smooth plane and/or a card scraper. So I’d pass on the mouth patch for now.
Wooden planes have way fewer parts compared to metal planes. In addition, none of these parts move (except that whole seasonal movement thing). So in my experience, they are much simpler to troubleshoot and fix than metal planes. Hopefully these tips will help you get that old wooden plane of yours back into prime working condition as well.