Mortising help needed

[Alex Yeilding]

I'm teaching myself to cut mortises by hand. Made a set of four frame and panel doors, and the M&T joinery worked great. But to keep me humble, the woodworking gods rewarded my next effort differently. This time, the tenons fit well, but when I dry assembled the door frame, it looked like something designed by M. C. Escher! :eek: My mortises, while clean and tight, were NOT parallel to the face of the board.

Any hints for how to assure that I am cutting perpendicular to the surface? I'm sure that much of the answer is "practice, practice, and practice", but I don't want to miss any hints that might make my practicing more productive.

Stock is squared properly; bench is flat; I ganged 4 stiles together, used a handscrew to hold them together and clamped the handscrew to the bench to hold the whole setup while I was chopping. I must have been holding the chisel a an angle when I was chopping. I guess I could clamp a square to the benchtop as a visual reference for vertical.

Anyone have any "tricks of the trade" they use to address this issue. P.S., I don't have a proper mortising machine. I'm not opposed to using a tailed router for this task, but want to develop the hand skills for times when there are very few to cut, odd sizes, etc., that wouldn't be easy to do by router.)

[Mike K Wenzloff]

Hi Alex--sorry to hear about the trials and tribulations!

I do the same as far as ganging them. I use the sides of the stiles to sight down. It's not a very conscious thing any more.

If I cannot stand at the end of my bench (which makes lining up everything) then I run them straight across the bench, or if too long, at an angle across the bench. Point being is my body is in-line with them.

There are times I basically stand to the side of them laid out on the bench, but mainly if the mortises are large ones.

As I cut mortises first, if I do mess one up, I pare it square and I have been known to patch a mortise and pare it parallel to the face. That way I can make that particular tenon to fit.

Take care, Mike

[Steven Wilson]

Alex, instead of having a square around just have a block of wood with square sides to use as a reference (say a 1 1/2" block). You can lay that up near your mortise marks while you start choping and use that as a vertical reference as you start your mortise. After you're in aways you should be able to continue square without reference. It's the same idea as drilling a straight hole without a drill press.

[Pam Niedermayer]

I find standing in line with the length of the mortise to help a great deal, easy to see when I get off square.

Pam

[Bob Smalser]

http://pic20.picturetrail.com/VOL12/1104763/5536778/70921478.jpg

One of the main reasons I find longer chisels so much faster is because they are so quick to plumb.

[Terry Beadle]

Charlesworth outlines in his book a technique using a hand router to surface the faces of the tennons. This is a real help to keep twists out of your joints. Esscentially you get your cheeks close to width but then by laying them flat on your work table and then using a hand router with a same thicknessed scrap, you move the router over the cheeks. There is a slip gauge made to test the thickness of the mortice to tennon fit. I'm probably not explaining it well but it's in his books on furnature making.

It's a goer.

[harry strasil]

For What its Worth, This is a little jig I came up with when first learning to mortice, to keep the mortice hole square.

Its just a piece of 1.5 scantling with square sides with a section cut away to allow the mortice chisel to set square two ways, the bottom drawing shows it clamped on a mortice layout.

http://img.photobucket.com/albums/v81/irnsrgn/wood/morticehelper.jpg

[Pete Bradley]

I use a jig very similar to Harry's. The only difference is mine has a longer elbow. I jointed one side of a doug fir 2X4 flat and then bandsawed it out. Not very neander, but it's been just the thing for hand-chopped mortises and several other tasks ever since. I think Bob's long chisel would probably allow you to go a little faster though since you wouldn't spend time lining up the jig.

Pete

[Charles Stanford]

Like someone else mentioned, just use a spring clamp to clamp a small piece of wood - say a 1x4 piece of Poplar that clears the workpiece edge by four or five inches. Clamp it on a little 'down the line' so it doesn't get in the way of mortising yet is still close enough to allow a quick visual as to whether the chisel is being held at 90 degrees. You'll become accustomed to sighting the chisel position against the guide. It will truly be second nature and WILL NOT slow you down at all.

I've chopped hundreds of mortises and still use a guide. There is nothing like the sinking feeling of knocking together a frame and have it arch up off the workbench like a pretzel. And worse, there is not an easy fix. It takes less than a second to clamp the guide onto the workpiece and of course the guide lasts forever.

[Alex Yeilding]

Thanks, all, for your helpful suggestions.

Will try Charles' idea of clamping a vertical piece to the board being mortised. I had similar ideas, but was "over-thinking it" to come up with solutions that were way too complex.

May also try Harry's and Pete's "jig", although vertical ends of the mortise have not been a problem for me--I save the last little bit of lenth for the end of the process, and finish it with paring cuts or "near-paring" very lightly hammered cuts that are easy to keep vertical.

I need to change my position to get in line with the piece being mortised. I had compromised that to clamp the piece near the front of the bench while avoiding the tail vise.

Still thinking about Bob's advice, and why a longer chisel would help. On this, I was using a Crown Tools 1/4" chisel that is 11" long. I don't like it as well as my old "pig-sticker" 5/16" with a meatier blade and handle, which is 12" long, but I think it is more a difference in heft and handle size and shape than length.

Terry, in this case, my tenons were fine, but I had forgotten that technique from Charlesworth. And now you've got my curiosity up--I don't remember the slip guage to measure tenon to mortise fit. Is that in one of his books? I'll dig out my copy of _Furniture Making Techniques_ if it is there.

Anyway, thanks to all. As expected, no magic bullets to obviate the need for practice, but now my praticing can be more productive!

[Bob Smalser]

...Still thinking about Bob's advice, and why a longer chisel would help.

http://pic20.picturetrail.com/VOL12/1104763/5457882/69859831.jpg


To get yourself started getting a feel for plumb, there is absolutely nothing wrong with drilling out the mortise and paring it to shape. All mortises larger than an inch have to be done that way anyhoo, so drilling and paring is also a required skill. It's easier to use an auger or even a power drill with bevel gages used as guides and keep plumb than it is to hold and strike a chisel. You may get a better feel for it faster.

Bevel gages adjust to 90 degrees too, and are designed to set upright to use as sighting guides. Glory be.

You'll go through pronounced phases or stages in your woodworking, and it helps sometimes to know what they are. Roughly:

You pass the first stage when you have sufficient control to cut square, plumb, and accurately to a scribed line with any appropriate tool. If you aren't teaching yourself to freehand sharpen, you'll needlessly delay the eye-hand control required in achieving this skill.

The second stage is when you can cut on the correct side of any scribed line without spending time thinking about it.

The third stage is when you get antsy about precision and begin fooling needlessly with your tools and machines, thinking they are what's keeping you from rapid progress. Machine tool tolerances done in wood, which moves around with every single change in humidity. Many never leave this stage, because they get hung up more on their tools and than their work.

Stage 4 is when you can consistently assemble cabinet and furniture projects square and plumb with minimal mistakes. You could qualify for a job as a journeyman for pay, and/or reliably sell your work for money.

Stage 5 is where you get much better at fixing your mistakes, the complexity of your projects increases and your efficiency and speed improve. You make more money....or your pieces gain more value in your hands if you aren't selling.

The final stages are when you trust your eyes and your hands more than your tools, although you are still measuring twice and cutting once. Building your first boat to break out of Stage 3 will further your progress toward this level of skill immeasurably.