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Chris Henke
03-29-2013, 7:13 AM
Hi all---I'm working on my first workbench, which is in the roubo style and cobbled together from a few different plans. I am still very much a beginner with hand tools and have learned a lot from building and making tons of mistakes on this bench.

The other day it was time to cut the tenons on stretchers between the legs. I recently purchased a pretty nice/pricey tenon saw from LN to help with the job, as I didn't really have any hand saws that were up to the task. The tenons are 4" wide x ~2.5" long x 1/2" thick. My cuts for both the cheeks and the shoulders were pretty bad---not very consistent, and also not to the lines. I tried a few different techniques, including putting the stretchers in the vise at an angle and trying to saw to two lines at the start, then proceeded down each line. But I always seemed to be off on one of the lines when I was tracking well on another. I was also surprised that, when I cut through the long edge of the shoulder to remove the waste along the cheek, I was cutting into the tenon itself---I couldn't seem to cut straight down and get an even cut without cutting into the tenon on either end of the cut. In one case, the tenon was cut into so deeply that it snapped right off when I accidentally dropped the stretcher on the floor!

Any tips? I'm going to scrap these pieces and cut four new stretchers. Thanks for any advice,

Chris

258449258450

Edward Clarke
03-29-2013, 7:29 AM
Cut the tenons off square and use the remaining too short stretchers for practice. That's what I'm planning on doing with the 6x6 spare leg that I have for my own workbench. My original 6x6 was long enough to make five legs so I'll use one to get the technique down correctly.

Adam Cruea
03-29-2013, 8:08 AM
Practice. That's what I've found.

I've also found if I start the saw at 45* or greater and follow the closest line down a ways until most of the teeth that are cutting lumber are below the surface, then drop the toe of the saw into the cheek. I have found this gives the saw something to track and since the tenon saw I use has very little set to the teeth (BA 16"), it won't hop out of the initial cut down the face.

If that's a little confusing, I can post pictures. I'm not sure it's the "right way", but I've learned there's not really a "right way" and "wrong way" in most of this.

Derek Cohen
03-29-2013, 8:32 AM
Hi Edward

I make 6 saw cuts for a tenon cheek.

As Adam wrote, saw diagonally along two lines. Do this for both cheeks. Now turn the stretcher around and do the same on the other side.

Having got this far, simply slip the saw into the kerf at the apex of the triangle you have created, and saw straight (horizontally) in this "guide" until you have reached the baseline of the shoulder. Do the same at the other cheek.

Now remove the shoulders (or do them first - my preference).

http://i13.photobucket.com/albums/a262/Derek50/Joints/Mortice-and-Tenon%20Primer/Sawingtenoncheek_zps85801131.jpg

I had a chance to try out one of Joel's saws at TFWW in January (and bought the saw) ...

http://i13.photobucket.com/albums/a262/Derek50/Joints/Mortice-and-Tenon%20Primer/Joel1_zpsc9490dc3.jpg

Regards from Perth

Derek

Chris Henke
03-29-2013, 10:12 AM
Thanks for the replies, everyone. I guess I just need more practice. Is there a generally accepted order of operations for cutting tenons? Seems like a lot of people start by cutting the long edge of the cheeks, but Derek said that he actually cuts along the shoulders first. Does this make it even harder to ensure you don't cut into the actual tenon?

Chris

Derek Cohen
03-29-2013, 10:25 AM
Hi Chris

I saw the shoulder first because I would rather overcut (if I do) into the tenon cheek (which cannot be seen) than saw the cheeks and overcut into the stretcher itself (which can be seen).

Regards from Perth

Derek

Matthew Dunne
03-29-2013, 10:26 AM
Chris,
I'm a fellow newbie, so take this for what it's worth. I found it extremely useful to practice a lot on scrap, for example drawing 10-20 lines and trying to saw to them. Over the course of days or weeks, I got better. Still not where I'd like to be, but noticeably improved.

Also, you may be doing this already: when I cut the shoulder, I first knife the shoulder line deeply. Then I use a chisel to deepen the line (chisel bevel on the waste side, obviously) and then take out a little sliver, creating a "V" notch with a vertical face on my cut line. I can drop my backsaw into that V notch, and saw down to my line. In effect, the show part of the cut is actually chiseled, rather than sawn. Like you, I cut into the tenon many times before I got sufficiently precise.

I usually cut cheeks before shoulder, but folks do both ways, I believe.

Adam Cruea
03-29-2013, 11:35 AM
Thanks for the replies, everyone. I guess I just need more practice. Is there a generally accepted order of operations for cutting tenons? Seems like a lot of people start by cutting the long edge of the cheeks, but Derek said that he actually cuts along the shoulders first. Does this make it even harder to ensure you don't cut into the actual tenon?

Chris

Like Derek said, due to oversaw concerns, generally doing the shoulder first is advisable.

Now, if you don't care if you accidentally oversaw, I can't see a reason to do one before the other.

Zach Dillinger
03-29-2013, 11:41 AM
If you saw the shoulders first you can split the tenon cheek waste away with a chisel. Much faster than sawing. Assuming you have straight-grained wood.

Jim Matthews
03-29-2013, 6:03 PM
I don't saw my tenons, I split them.

You saw the shoulders, as normal but use a chisel to split off the waste.
Paring gets you down to the desired tenon thickness.

It's counter-intuitive, but I get better control than with a saw.
http://www.youtube.com/watch?v=H3VTOpumi58

Derek Cohen
03-29-2013, 8:01 PM
A good technique, but don't try that unless you are certain the grain is running straight. :eek:

Below, 22" wide tenon ...

http://www.inthewoodshop.com/ShopMadeTools/BuidingaBench3_html_2fde45c5.jpg

http://www.inthewoodshop.com/ShopMadeTools/BuidingaBench3_html_15ae5232.jpg

:) :)

Regards from Perth

Derek

Paul Crowe
03-29-2013, 11:38 PM
Some food for thought in at PBS try here http://video.pbs.org/video/1772025726/ or Google woodwright sawing secrets

lowell holmes
03-30-2013, 10:44 AM
Add this link for Paul Sellers.

http://www.youtube.com/watch?v=H3VTOpumi58

Jonas Baker
03-30-2013, 1:28 PM
Derek, I assume those cross cuts for the tenon shoulders were cut with a table saw? Just wondering, as I don't have a table saw, so it would be interesting to hear how you did those cuts if you used something besides a table saw.

Best,


Jonas

Derek Cohen
03-30-2013, 8:46 PM
Hi Jonas

You are correct. I have a sliding tablesaw, which is great for crosscuts for long and thick hardwood. If I did not use one I would either have rigged up a circular saw on a guide. Sawing it by hand is doable, but comes in third place for a job such as this. Of course you may have no alternative :(

Regards from Perth

Derek

Adam Cruea
03-31-2013, 12:05 AM
If you saw the shoulders first you can split the tenon cheek waste away with a chisel. Much faster than sawing. Assuming you have straight-grained wood.

I forgot out this as it is an option.

When I was making the tenons for my bench, I needed to go down 4 inches, but only had a handsaw with a 2 3/8" plate. I sawed down to the spine of the saw, then tilted the saw until I could get the heel to the shoulder. Then pop a chisel (a wide one) in the kerf left by the sawplate and give it a good rap with a mallet. The waste will pop right off if done right, and there's very little left to pare down.

That being said, this was done in hickory with straight grain (mostly). If I remember right, a couple of time the grain went a little hinky and I ended up with a few strands holding the waste for dear life and it would take too much out of the cheek. Not that it was a problem, because the ripped out cheek was hidden.

steven c newman
03-31-2013, 11:45 AM
I also cut my tenons like that guy from Perth. Except, I use just a coping saw258633I was cutting until the top of the blade was flush with the surface,258634a few whacks with a sharp, wide chisel clears the waste down to the layout line, then a little work to pare it smooth258636rotate and repeat as needed258637Takes MAYBE ten minutes per end of apron.

Chris Henke
04-01-2013, 7:58 AM
Thanks for all the great tips, everyone. I learned a lot from the pictures and especially the videos linked---I will try out the techniques shown for both the splitting method as well as some of the sawing techniques shown by Schwarz. I would like to eventually build one of those saw benches shown in the video with him and Underhill (not to mention get one of those nice panel saws...).

Chris

Jim Koepke
04-01-2013, 1:27 PM
Thanks for all the great tips, everyone. I learned a lot from the pictures and especially the videos linked---I will try out the techniques shown for both the splitting method as well as some of the sawing techniques shown by Schwarz. I would like to eventually build one of those saw benches shown in the video with him and Underhill (not to mention get one of those nice panel saws...).

Chris

Chris, you are surely welcome by everyone who responded. The free sharing of information is what makes this forum so great.

This is a little different than the one in the video but it can be a starting point:

http://www.sawmillcreek.org/showthread.php?146777-Saw-Table-Project

You can customize it to suit your needs by including a shelf in the bottom, runners along the side or any other innovation of which you can dream.

jtk

steven c newman
04-01-2013, 6:47 PM
Just got done sawing tenons on for aprons for a small table I am building.258754I just sawed down until the teeth are just below the surface (easy depth stop)258755Chisel splits off the waste, then it will pare the tenon flat, Repeated until all faces are done258756in my case, that is three sides. Quick and easy.

Chris Friesen
04-01-2013, 7:31 PM
The tenons are 4" wide x ~2.5" long x 1/2" thick. .... In one case, the tenon was cut into so deeply that it snapped right off when I accidentally dropped the stretcher on the floor!

It looks like you're using softwood. Personally I'd go thicker than 1/2" in softwood, especially for a workbench--at least 3/4" and maybe 1". You don't need much of a shoulder for structural purposes, and the tenon needs to take a lot of force. Since you're going into a big fat leg you can have a big fat tenon.