The Rear Legs
Note: When I talk about the many parts of this chair, I name them as if I were sitting in the chair.
Out of all of the chair’s parts, I won’t say the rear legs were the most difficult to create, however they were certainly the most involved. There are so many different things you’ll need to perform in order to complete these two very important parts.
The very first thing I did was to trace and cut out a paper copy of the full-sized rear leg pattern found on Mr. Rodel’s plans. Once done, I then transferred that paper copy to a scrap piece of half inch plywood. This would be my final template for all rear leg blanks.
Make sure you make your plywood template at least 2 or 3 inches long on each end!! That extra length comes in handy later when you screw the template down to your rear leg blank. Plus you’ll want to make sure that your template is as close to perfect as possible.
One very important note. There’s an area on the front edge of the rear leg that needs to stay extremely flat throughout the entire creation of the rear leg. This area is where the side stretcher meets the front of the rear leg. The side stretcher comes straight out from the front face of the rear leg parallel to the floor, so it’s extremely important to remember to keep that area very, very flat and (eventually) perpendicular to the floor. I call this flat spot the “stay away zone”. You’ll see in the photo below that I’ve marked the “stay away zone” with upper and lower pencil marks on the rear leg template. These same two marks then get transferred to each of the rear legs.
As mentioned in the “Introduction” part of this class, I chose to laminate two fairly wide pieces of cherry for the rear legs. Each piece was approximately 8 inches wide and 50 inches long.
If I happened to have a strip of yellow sap wood running down the full length of two pieces, I made sure to butt those sappy areas together before glue up…giving me more “good looking” cherry to lay out my rear leg pattern outlines.
Before tracing out the rear leg patterns onto my wide blanks, I created one straight edge on the blanks using my table saw and/or edge jointer. This created a great place for me to lay the pattern for the “stay away zone”.
(I never touched the “stay away zone” again until it was time to lightly sand the blade marks off just before final assembly time.)
Once the pattern was traced onto the blank, it was off to the band saw to cut the first rear leg from the blank. I simply stayed just outside my pencil marks. You can faintly see my “stay away zone” marks in the photo below.
After cutting out that very first leg, it was back to the table saw to create yet another “stay away zone” on the remaining part of the rear leg blank. And so on…
Now’s the time to ask yourself a very important question. How are you planning on finalizing the shape of your rear legs…on the router table, or sanding your way down to the final pencil line with an oscillating spindle sander?
Originally, I decided that I was going to finalize the shape of my rear legs on the router table using a very tall top-bearing straight bit along with the plywood pattern affixed to the rear leg.
Keep in mind that my rear legs were made from two pieces of cherry glued together. This introduced the problem of wood grain running in all sorts of directions. On two or three of my legs I was unpleasantly shown what a very tall router bit can do to wood grain going in two different directions. Not a pretty site. Off to the scrap pile they went. :(
I also quickly discovered the horrible aftermaths of what happens when your template is not affixed to the rear leg blank in a secure fashion. See photo below.
So the bottom line is…if you’re using solid cherry for your rear legs, then the router table way is probably your best bet. It sure makes a beautiful, clean rear leg once you’re done. (Just make darn sure that your template is not only screwed down, but also taped down in many places with double-sided carpet tape.) In the photo below, this was not quite good enough. I should have used more tape.
If you’re going to laminate two parts of wood together for your rear legs, then I’d highly recommend that you choose not to go the router table way. I ended up finishing my rear leg blanks on the oscillating spindle sander. See “Caution” below.
Caution: Remember back when I mentioned those three famous words? Consistency, consistency, consistency. This is NOT a consistent way to complete your rear legs. I found out the hard way that no matter how careful I was on the oscillating sander, I do believe I ended up with at least 10-15 different sized rear legs out of the 40 needed. Not much of a difference…but enough to bite you in the rear later.
My remedy? I laid out all 40 legs and then did my best to match them up with a twin as far as size and shape. Once done, I’d mark each pair with a matching letter. (See photos below.)
And the pile of rear legs grows… (You can really see those “stay away zones” now.)
Once all of your rear legs are shaped to their final outline, it’s time to start thinking about making your mortises…and there are a few. Three on the inside face and two on the front face.
To help layout the upper two inside face mortises, I laid out my subassembly consisting of upper and lower back stretchers and the back splat assembly. I positioned this subassembly onto my rear legs, and then marked the exact centers of each tenon onto the rear leg. This step assured me that this subassembly would drop right into place at glue up time.
(If you’re not quite ready to glue up that subassembly, you can cheat a little by marking your mortise locations like I did in the 2nd photo below.)
Seeing that I have one of Leigh’s mortise and tenoning jigs, it was a no-brainer as to how I was going to create my mortises. I did, however, have to make a crude clamping jig for the rear legs. The two wimpy little clamps normally used on the Leigh were far from adequate. You have to keep in mind how much wood you’re plowing out for these fairly large mortises. (In the next photo you’ll notice that I now have 3 very strong clamps instead of two wimpy ones that came with the Leigh jig.)
The following two photos show my mortising setup. Note the wedges used behind the rear leg in the second photo. This is a “must do” step to keep things safe during the creation of your 3 inside face mortises.
This is what happens when you don’t have your legs securely clamped. I actually had a much worse episode than what you see in the photo below. This leg was salvageable. The other one was not. Very, very dangerous things can happen if you don’t have things securely in place!!
And, of course, what shop would be complete without a new toy. Obviously you’ll want to make your mortises just a bit deeper than the length of your tenons, so this one has just a little ways to go.
I won’t go into any more detail about how to create the mortises. This is just something that you have to sit down and plot out very carefully. Don’t be afraid to write notes near each mortise reminding you which mortise is this deep and that wide. It really helped me keep things straight throughout the mortising stages.
As for the little mortise for the lower stretchers, (the one on the front face of the rear leg near the floor), go back to my “Front Legs” chapter to see how that mortise is created.
It’s time now to move on to tapering the outside face of each rear leg. For this I once again built a very crude jig. You can find many different variations by Googling “leg taper jig”. They all work great. I built mine to accommodate both left and rear leg taper cuts.
I started out with a scrap piece of MDF. I glued and screwed a runner to the bottom of the MDF, and then ran it through my saw to cut the blade edge of the jig on both sides of the table saw blade.
From there I mounted two pieces of scrap plywood that I used to hold my two clamps.
And finally I mounted two moveable chunks of MDF that allowed me to move the leg to where it precisely needs to be during the cut.
Make sure you orient the leg in your jig so that the inside mortises face the center of the jig. See photo below.
In the photo below, note that the top of the rear leg is positioned closest to your body. It sits in the notch made in the piece of MDF closest to your body revealing a 1/4 inch hanging over the outside edge of the jig. At the far end of the jig is the second moveable piece of MDF that allows you to set the exact “starting point” of the cut on the outside face of the leg. So the tapered cut starts just above the “stay away zone”. This jig worked fantastic for me!!
I’ve since had to build another taper jig seeing that I replaced my old Delta 10” Contractor’s saw with a 3HP 220V SawStop. (Very Sweet…with a capital “S”.)
The last step to the rear legs is the creation of the pyramid-shaped tops of the rear legs. I must admit that on my very first chair, I chickened out and bypassed this step. So yes…I have an oddball in the family of 10 chairs.
An important note to know is that all four faces do not meet the top of rear leg at a 90 degree angle. During the creation of the pyramid top on the front legs, things were quite simple seeing that the four faces meet the top at a 90. This easily centers the peak on the top of each front leg. Not so on the rear legs.
Enter my savior. There is a gentleman who happens to be a member in this fine LumberJocks.com family who was so very kind to share his steps on how to create the pyramids on top of the rear legs. I owe such a huge “thank you” to a Mr. Marc Rosen. Marc emailed me simple steps and great photos showing exactly how to perform these steps.
Up to this point, you have a whole lot of hours invested into your rear legs, and by chopping the tops of the rear legs off flat is an easy task to perform to move things along much more quickly. However, please don’t make that horrible mistake. Go for the pyramids. I cannot tell you how many people comment on that wonderful bit of detail. Marc…thank you so much for sharing your talents!! I owe you big time.
With that said, please allow me to pass Marc’s wonderful and easy tips on to you.
Note: Before I start, I must mention that I made one minor change to the pyramids on our chairs. The plans call for a 22.5 degree pitch. As mentioned in my “Front Legs” chapter, I chose to go with a lesser degree angle of 11 degrees.
This final step of creating the pyramid tops to each rear leg is the part that I lost many, many nights of sleep over. I tend to over-think things way too much, so here goes.
As mentioned earlier, not all four faces of the rear leg are at a 90 degree angle to the very top surface. The inside face is definitely 90 degrees to the top of the leg. The front face is either 90 or very darned close. The outside face we know quite well is not 90 degrees seeing that we shaved some of that face off in an earlier step. And finally, I discovered that the back face is about 2 degrees off at approx. 88 degrees.
Before receiving Marc’s great notes and photos, I laid awake countless hours thinking about how in the world I was going to get that peak to meet in the very middle of that pyramid with all of the mentioned variables.
(I’m hoping that Marc will jump in with some comments in regards to the next steps below to clarify whether or not I needed to do what I did differently compared to his pyramid creation. Plus, the more I look at his photos, I think he just might have done the same thing that I did. Just not too sure at this point.)
Confused yet? It should become clearer in a moment.
Set your table saw blade at the angle you desire (11 or 22.5 degrees) and at a height that is high enough to make the cut. In my case the blade was set to 11 degrees. Make sure you’re using a sacrificial fence!!
Set up your miter gauge at 2 degrees clockwise. See next photo. (This is where Marc’s notes and mine just might differ. But once again, I’m not too sure about this. Marc???)
Place the rear left leg onto your miter gauge so that the outside face is facing down (inside face with mortises facing up) and the back face is up against your miter fence. The bent part of the lower leg should be pointing towards your body. This should put the very top of the rear leg “flat or square” up against your sacrificial fence.
The next photo shows that 2 degree clockwise setting in a little better fashion.
Make your cut. (Take it very slow to eliminate tear out.) This cut should start your pyramid cuts by cutting the outer quadrant of the pyramid. That would be the 1/4 of the pyramid facing the left outside edge of your left rear leg…as you’re sitting in the chair.
Once you’re done with the first cut, reposition your miter gauge back to zero degrees and flop your left rear leg over onto its opposite face so that the bent portion is now facing away from your body.
Make your cut. (Again, take it nice and slow.)
You should now have your first two pyramid cuts complete. One on the outside edge of the top and one on the inside edge of the top.
I apologize for not having photos of the next two cuts, but they’re fairly simple.
Return your table saw blade to 90 degrees straight up and down. Leave your leg right where it is for now, but turn your miter gauge at 11 degrees clockwise. (Or 22.5 if you choose to do so.)
This next cut will create the part of the pyramid found on the front of the leg top. Once done, simply rotate your miter gauge to 11 degrees in the opposite direction (or 22.5) to complete the final side of the pyramid. No need to move or reposition the leg. Leave it right where it is.
IMPORTANT NOTE: You may want to sneak up on these two cuts. I found that I couldn’t rely 100% on my table saw fence any more.
As always, try all of the above steps on a bad leg. And yes, I know you just might have one. :)
And as mentioned in the “Front Leg” chapter, a little 400 grit sandpaper takes away any minor boo-boos.
See you at the next chapter…
Dale “Gramps” Peterson.
-- If at first you don't succeed...DO NOT try skydiving.