Tonight I turned off all the power tools and decided to take the plunge and try chopping a mortise or two to learn how to do this by hand. I’ll have to admit I’m in awe of you folks that do this routinely. In a little over a half hour I got a 1/4″ x 1″ x about 3/4″ deep mortise cut in a piece of scrap hickory I had lying around.
The question is, once you mark out the mortise and lightly start the cut vertically around the perimeter, when you start actually chopping out the interior, do you just lever out the waste without chopping down on the cheek side of the mortise? Hickory was the closest thing at hand when I got this compulsion for self abuse so I suspect I should practice, to start with, on something like …. uhmmmm balsa wood? (grin).
I can see where a much *much* better set of chisels would be a worthwhile investment as well.
Replies
It depends what kind of chisel you are using, Dennis. If you are using a bevel edged chisel designed for light trimming, such as dovetail clean outs, mortising is not so easy. Mortice chisel have a thick heavy blade, and the deep sides are self guiding in that they guide the cutting edge perpendicular to the scribed cheek marks as you chop deeper.
With this type of chisel (mortice) and with some practice, you should be able to belt out a mortise of the dimension you described in about four or five minutes-- when used effectively. These big chisels are wood eating bruisers. Traditional woodworkers do not use them daintily, and they whack them hard with heavy mallets to slice through the grain, and they lever out the waste forcefully.
You normally don't start by defining the perimeter with the chisel. It fits between the mortice gauge lines which were set by using the chisel to space the two pins. In traditional work, the mortice is cut first-- because the chisel is a fixed width, and the tenon is cut to suit.
One reason for at least a small shoulder at each end of the tenon is to hide any indenting or bruising at each end of the mortice that might be caused by the chisel as you lever out the waste. Slainte.
Website The poster formerly known as Sgian Dubh
So the cheeks of the mortise aren't scored at all then. The first time I tried whacking the chisel down parallel to the grain and of course I split the end of the board.The cheeks seem to be pretty rough. Sorry to sound like such a dweeb but does a mortising chisel tend to leave a cleaner surface on the sides of the cut, then?
And no, I've never been accused of being 'dainty'. (grin)
Next step is to buy a good mortising chisel and start again.
Thanks for the reply............
Dennis in Bellevue WA
[email protected]
Dennis, others have given good information, but here are the basics of hand chopping mortices. Let's assume it's a simple four sided frame where all the parts are of equal thickness and width.
1. Start by truing up your timber. Flatten and mark the first wide face trued up with a face side mark. It looks like a pigs tail where the end of the tail goes towards the edge to be straightened and squared-- see 2 below.
2. Straighten and square one narrow edge to the just flattened face, and mark it with a face edge mark. It's a V where the valley of the V roughly meets the end of the face side mark.
3. Square and true the other face and other edge from the first two as at 1 and 2 above. (All this work can be done with hand tools or with powered tools, such as saws and planers.)
4. Cut the tenoned parts to the required length-- include shoulder to shoulder length, plus the length of the two tenons. Cut the parts to be morticed a bit long-- The overhanging horns are removed after assembly.
5. Set the parts up on a flat surface as you plan to assemble, with all the face side marks facing up. Mark each corner, A-A, B-B, etc..
6. Take the selected mortice chisel, and use it to set the gap between the pins of a mortice gauge.
7. Now with the pins of the gauge set, find the centre of the timber to be morticed by adjusting the stock on the shaft of the gauge-- to find the centre, use the stock of the gauge from both faces of the trued timber until pinprick points coincide either side of centre when pressed into the timbers edge with the stock of the gauge used from either face-- I hope that makes sense, ha, ha.
8. With the mortice gauge set, mark the position of both the mortise and the tenon by running the gauge stock only against the face side of the wood, i.e., the face with the pigs tail marked on it. If you're a bo'hair out of centre, the parts will all line up because all the face side marks face the same way, i.e., in this case, up.
9. A bit I'm not going to get into here because I want to get to the chopping, and blah, blah, but next mark in the relevant shoulder lines of the tenons and length of the mortice.
10. Chop out the mortise with a mortise chisel. Put the part down on the bench, and maybe cramp it down. Stand straight on looking along the length of the scribed in lines defining the width of the mortice. Hold the blade of the chisel between your fingers and thumb at about the middle of the mortices length, bevelled edge away from you so that the cutting edge spans between the scribed in mortice width lines. Whack the end of the handle with a mallet to create a chip. The chip will sort of break up towards you.
11. Move the chisel back away from you about 3-4 mm, span between the lines again, and whack it again. Keep chipping away from you until you get near the end of the length of your morice.
12. Now turn around, and do the same from the middle of the mortice again towards the other end of the mortice.
13. Lift out all the chips just formed. Start in the middle of the mortice again, and you'll find that the chisel is guided by the existing shallow mortice, bevel side away from you again, and whack it, create a chip, step back a bit, belt the thing again, and so on, gradually deepening the mortise you started.
14. Keep on deepening the mortise this way, but you'll find that eventually you can use the chisels flat back to pare down to the lines that define the length of the mortice too.
15. Okay, so, you've cut the mortice, and now all you have to do is cut the tenons with a tenon saw to suit, and because all the marking was done rigorously from only the marked face side-- the pig tail side, the wide faces will line up at assembly.
16. This is a short summary only, but more than long winded enough, but I hope you get the general idea.
17. I see that mortice chisels can be got from Garrett Wade-- Sorby brand, and they also offer swan neck chisels which are handy for cleaning out the bottom of mortices. I'm sure there are other suppliers too, such as maybe Lee Valley? Both companies have web sites which I'm sure can be found easily enough, and if you take a look, you'll see how square and stout mortice chisels are, and because of their squareness and stoutness, you'll probably be able to picture how they are self guiding once you get a bit of a start chopping a mortice.
18. I haven't used a mortice chisel seriously in maybe 25- 30 years to chop a mortice, so my suggested methodology as outlined above might be a bit rusty, but once you've had to do it time after time as I used to have to do, it's kind of like riding a bike. Anyway, sorry for the long post, and forgive any speeling (sic) mistakes, bad grammar, repetitions, etc., for I'm not going to run this past the spellchecker before I post, ha, ha. I'm in a hurry. Slainte.
Website The poster formerly known as Sgian Dubh
The method of using a brace and bit to cut a mortise is described in "The Complete Woodworker" ed. Bernard E. Jones, Ten Speed Press, as "the coach-builders' method" of cutting a mortise and is briefly described as an alternate method to the method described above. The "Complete Woodworker" is something like "The Ididot's Guide to Woodworking," circa 1910. The Ten Speed Press edition is a paperback reprint that looks like it had an American edit at some point.
The brace and bit method works for me because I don't have any "pig-sticker" mortise chisels at the moment. Sometimes if I get in a hurry, I use forstner bits and a jig on the drill press. At the last resort,...uggghhh,...a jig and the router. Sometimes I wish I had a dedicated mortising machine, just like some of Norm's machines, ha ha.
Dennis I've cut a few mortises by hand and enjoyed doing so, but I've learned I can have just as much fun if I drill out most of the waste and pare out the finished mortise. It's all about having fun, right!
God Bless
les
I'm an admirer of all types of hand work, Les, from woodworking to blacksmithing. Thus I decided to embark on an effort to make things, from time to time, with the approach that electricity hasn't been invented yet. I thought about drilling out the mortise but my technique with a brace & bit is worse than my chisel work.
I realize that quality hand work only comes with years and years of practice - I don't expect to produce collector quality stuff any time in the near future. But now that I'm all but retired, I'm running out of time (grin)
Thanks for the reply. Learning is the fun part - the end product is merely a bonus.
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Dennis in Bellevue WA
[email protected]
Ditto to what Les said about removing the waste by drill (or brace and bit).
If you want to stay with hand tools (i.e. you're listening to music or an audio book), life doesn't get much better than a box of pre-WWII Russell Jennings double twist auger bits with well-sharpened spurs, and a Miller's Falls "Parsons" brace. You can use that to remove most of the waste in the mortise and clean up with bevel-edged bench chisels.
Recently I tried making mortises by using a forstner bit on a drill press, then chiseling out the waste. I found that even with a very sharp chisel (when I tried cutting the hair on my left forearm the hair on my right forearm also fell out), the cheeks of the mortise got all splintered out inside the mortise, i.e., the chisel wasn't just slicing the wood but was mostly tearing it. It was very frustrating for someone trying to use more handtools. I ended up cleaning up the mortises on the router table, which was effective but dusty and LOUD. I still can't figure out what I was doing wrong, if anything.
I can't either, pal. If I had the expertise, I would tell you the secrets. My system works for me in softwoods like pine, redwood and douglas fir, and fairly soft hardwoods like cherry, poplar and walnut.
I get my chisels as sharp as possible with sandpaper to 2000 grit. Sometimes I try honing above that with diamond paste on MDF. Sometimes, if the moon is right and the spirit takes me, I will say the magic incantation, tap my heels together, and do the last bit of honing with and 8000 grit Japanese waterstone dressed with the Naguro paste. As I'm doing this, I say the only Japanese phrase I remember other than "Domo arrigato gozaimus" dating back to a Japanese girlfriend I had in San Diego fifteen years ago. The phrase translates as, "I have to go to the bathroom."
I know I got the chisel sharp if I cut slice the mortise square just by kind of standing over the mortise and leaning down onto it. I slice off just little slivers of the waste at a time. I try to avoid having to tap the chisel very much with the mallet.
Hope this helps. Good luck.
You apparently chop mortises better than you speak Japanese. The phrase you quoted means "thank you very much." BJ
I was working on some Christmas present projects in December involving both mortise and tenons and handcut dovetails. With two bandaids on fingers from chisels that tried to go ballistic, lots of chips and shavings all over the shop and a motley and mongrel assortment of dulling ebay-bought chisels, I was starting to feel incompetent at just about everything. It's a shame that the Japanese are too civilized to have some really good curse phrases - could've used 'em. Presents came out all right, though.
Hi Ed ....
Duhhhhh on me! I tried using the brace & bit but chucked a forestner bit in it instead of one of my grandads old Irwin augers. Chances are they're not the quality of what you suggest but the idea of drilling holes with the same tools he held in his hands ....
I'll try that next. Drilling is definitely an option with a hand-held non-electric drill.
The biggest problem I'm having, given my limited tools (quality wise and appropriate to the task) is the 'cleanliness' of the mortise sides, bottom and end.
Practice, practice, then practice some more.
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Dennis in Bellevue WA
[email protected]
You definitely need a mortise chisel for this to be practical: Mark out the mortise with a mortise guage set to the width of your chisel. Clamp the workpiece to the bench so you can sight down it lengthwise. (It's important that the chisel not tilt side to side) Sit a square upright on the bench nearby for a visual reference. Set the chisel between the cheek lines, clobber it with the mallet, and lever out the chip. I don't have any hickory, but I cut the size you mentioned in oak, and it required about 20 whacks, and a little clean up with a paring chisel to get it right. Took about 5 minutes. Nick
The cabinets I'm considering building have ash frames with panel infill. For the sake of doing it, I want to do the mortise/tenon thing. That's what got me interested in hand chopping the mortises primarily since I was even having a time of it getting my router, table saw and whatnot properly set up to do the job by machine. Thus I've been practicing with the ash since my initial efforts with the hickory. Ash seems a bit easier to work than hickory.
Every suggestion and all the reading and illustrations I've seen say nothing about cutting down the cheek sides of the mortise - I guess this just 'happens' when you've got the right chisel and lever out the waste, eh? Asked the question before but I'll invite you to add your perspective. I don't get a very clean surface on the mortise cheeks this way. We generally pare the cheeks to some degree when we're done then fit the tenon to what we end up with?
Pretty basic stuff here - appreciate your feedback.
Thanks.
...........
Dennis in Bellevue WA
[email protected]
Dennis,
I guess I'm a bit of an iconoclast even among hand tool users...
When I chop a mortise, after laying out with my mortising gauge, I deepen the layout lines with either a sharp chisel or a marking knife, and then use the mortising chisel to remove a thin piece from within the lines. I don't remove much, I try to make a trench that's an eighth of an inch or less deep.
The reason? Certainly not because I have to define the edges; as others have written, a heavy mortising chisel will produce a mortise with straight sides. Primarily I make a little trench so I can more easily register the chisel on the first pass; and to a much lesser degree, to reduce the odds that I will splinter the edges of the mortise.
To reiterate: you don't need to define the edges if you're using a mortise chisel. I do it my way because I've found I chop better mortises quicker. The sides of my mortises are straight from the beginning, which means I don't have to do any paring on the sides to true them up; and that means I can use the existing gauge setting to saw the tenons.
Alan
Dennis,
A few weeks ago I had to cut about a dozen mortices in some Doug Fir. Now I don't know technique from a hole in the wall, and I did not have a motice chisel..and the mortice was about 1.5x2.5x2.5..ie rather large. The first mortice took about an hour and the last took about 10 minutes. I kinda started in the center to get to the desired depth and then pared back to the lines...a little at a time...last mortice fit on the first try. My theory is ya gotta make space for the chips for the chisel to do its thing...
Thanks, BG -
My practice sessions would suggest that what you describe is the appropriate technique. I get a cleaner end result by working from the middle out.
Broke down this afternoon and tried drilling a row of holes with a forestner bit in the drill press. It actually wasn't a lot easier except that with a freshly sharpened chisel I could just about pare down the cheeks with proper body english alone without using a mallet.
I'm off to work on our new place up north for the long weekend and won't be able to get back to my practice sessions until next week. Will definitely invest in some proper chisels by that time!
...........
Dennis in Bellevue WA
[email protected]
Alan -
I think your approach is advisable for beginners like myself. I find cutting a line around the mortise (outlining it) is a big help in maintaining proper size and controlling what subesquently happens.
I'm still working (practicing) with my cheap chisels just to get the feel for things so until I get a decent mortise chisel (or three) I'll not worry too much about the 'finish' inside the mortise. I still reserve the right to come back and whine more thereafter, though (grin)
Thanks for taking the time to assist... It's amazing what I can accomplish even with three thumbs.
...........
Dennis in Bellevue WA
[email protected]
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