This is the fifth part in a series on making a moulding plane. You can read the previous posts using these links: Making a moulding plane: Step 1 – The blank, Making a moulding plane: Step 2 – Layout, Making a moulding plane: Step 3 – Making the grip and escapement, and Making a moulding plane: Step 4 – Boring (the Wedge Mortise).
We left off in the last post with the wedge mortise cut and squared up. Now it is time to bed the iron and fit the wedge.
Bedding the iron is fairly straight-forward. The first step is to put the blank iron (which can be purchased from Lie-Nielson Toolworks) into the mouth of the plane so that the tang (the long skinny part of the iron) is against the blind side of the escapement and runs up through the wedge mortise. The first time you do this, the result should look something like the photo below.
At this point, the mouth of the plane should be too narrow for the iron to fit against the bed of the escapement. The next few steps are to use a float to open up the mouth slightly so that the blade will fit against the bed. Opening up the mouth will create a slight angle on the front of the escapement (the breast angle) that is called the “wear”.
Go slow when cutting the wear angle. Only open the mouth a tiny bit at a time and check your progress by inserting the iron after every few cuts with the float. At this point, you don’t want the wear to look like the photo above, You just want the iron to fit against the bed.
Once the iron will fit against the bed, you want need to start the process of fitting the wedge. You will have to have the wedge inserted to make sure the iron is properly bedded. To start, you will need a piece of stock just slightly thicker than the width of your wedge mortise. For a # 6 plane, we are shooting for 3/16″ The wedge should be cut from this stock so that the grain runs down the length of the wedge. The angle of the wedge should be 10º. The wedge doesn’t need to be angled down its full length.
Once you have the wedge blank a little thicker than the mortise, you will start removing a little bit of the thickness at a time until the wedge just fits and takes a little effort to pull out. To remove this material, you can use a finely set smoothing plane, a float, sand paper, or any other method to remove small amounts of material in a controlled manner. I prefer to use my crank-neck float. Remove a little material, test the wedge in the mortise for the proper fit, rinse and repeat.
Once the wedge is the right thickness to get a good fit in the mortise, you will need to work on fitting the angled edges to the bed and breast angles of the mortise and escapement. To do this, insert the iron blank into the plane body as you did earlier when opening up the mouth of the plane. Insert the wedge into the mortise and give it a tap with a wooden, plastic, or rubber mallet. Metal hammers should only be used on the wedge with VERY light taps. Otherwise, you may end up disfiguring or breaking the wedge. Look at where the wedge meets the top of the mortise and check out where it comes out of the mortise into the escapement. When the wedge is well fitted, there shouldn’t be any gaps at the top of the mortise and its front and back edges should be in contact with both the iron and the breast of the escapement. Unless you are skilled or lucky, you will probably have to make some adjustments to the wedge to get this kind of fit. If the wedge fits without gaps at the top of the mortise, but there is a gap in the escapement between the wedge and the iron or the wedge and the breast of the escapement, some material will need to be removed from the top part of the wedge where it seats into the mortise. If the wedge is tight against the iron and breast of the escapement, but there are gaps at the mortise, some material needs to be removed from the tip of the wedge. Ultimately, you will want to keep both sides of the wedge straight, so when you’re making these adjustments, you are really trying to make small tweaks to the angle of the wedge.
Once the wedge is fit, you can check the bedding of the iron. Insert the iron into the plane body and tap in the wedge so that the fit is snug. Check to make sure that the tang of the iron is contacting both the back of the wedge mortise and the wedge. Then check to make sure that the iron is contacting the bed of the escapement. If there are any gaps, which there probably will be, you will have to do some more float work to get the bed good and straight.
One way to do this is to color the side of the iron that rests against the bed with a dry-erase marker. Insert the iron and wedge as described above and tap on the tang of the iron with a small hammer to push it out of the plane. If you look at the back of the iron, you will get an idea of where any high spots in the bed are because the dry-erase marker will have been rubbed away. If you look into the mortise with a light, you should be able to see the high spots because of the color from the marker that rubbed of on them. Use a float to remove these high spots.
Take your time and repeat the process of coloring the iron and testing for and removing high spots until the nearly all of the dry-erase marker is removed. This will let you know that the iron is well bedded.
I will have to put the rest of this series on hold for a few weeks until I get a grinder and the equipment I need to heat treat the plane irons. Once I have those in place, I’ll show how to profile the sole of the plane and the iron.
Until next time. . .