I have yet to get any consistant advice on use of a corner chisel to square up a mortise. I have 3/8″ mortises that will be recieving through tenons. The mortises were cut with a router. I am trying to squaure up the round parts with an Iles 3/8″ corner chisel. I have had mediocre success.
First what is the little protrubance on the chisle edge for? Next one person said I needed a 1/4″ corner chisel. Another person said to use a mortise guage to mark the morises route them and cut out to the lines with a 3/8 mortise chisel. Still another told me to use a chisel and just pare them free hand. The last has been less than stellar. Being through tenons I need neat mortises. To say the least I am confused. I doubt highly I will cut them by hand as I do not have any mortise chisles and they are expensive.
Replies
Bonka,
Not seeing your chisel, I am guessing that the protuberance is at the point or corner of the chisel. It has no purpose, it just "is". It results from the extra metal that is in the corner when the outside sharp or square cotner meets the bevel which often has a slightly radiussed inside corner. The nearer the inside corner is to sharp (no radius) the less obvious will be the protuberance.
Now as to your thru mortises. I'd recommend using a mortise chisel, a firmer chisel, or a common bench chisel to square up your mortise ends, in that oerder of preference. That is, if you have a mortise chisel, use it, if not, and you have a firmer, use that. Barring all else, usewhatever bench chisel you have. The problem with the corner chisel is that it wants to twist as you push it into the cut. A common chisel with its single edge will be more inclined to stay on task, as it were. A mortise, or a firmer chisel's sides are square and unbevelled, so they will key themselves to the sides of the mortise, allowing you to nibble your way squarely back to the end of the mortise. A butt chisel's sides are bevelled back, so you will have to work a little harder to keep on track if using one. You might want to work alternately on the side and the end of the morise, extending the cut a bit at a time. A pair of bench chisels might be easier for you; use a wider one to pare down the side walls, working down til your last paring cut is keying off the routed surface of the sides, and extending the sides, then change to a narrow one and cut off those "rags", extending the end of the mortise, alternate these two actions til you are home. Trying to make the squaring cut at one stroke will generally cause heartburn, by bruising the end of the mortise/breaking the shoulder, twisting out of square, undercutting, or combination of the three.
A scribed (knifed) line marking the end of the mortise will help you by giving you a place to drop the chisel into on that last paring cut. Also, working from both outside faces til you meet in the middle, slightly undercutting if necessary,will give you the best looking results from the show surfaces. A sharp chisel never hurts either.
Ray
I have yet to get any consistant advice on use of a corner chisel to square up a mortise. I have 3/8" mortises that will be recieving through tenons. The mortises were cut with a router. I am trying to squaure up the round parts with an Iles 3/8" corner chisel. I have had mediocre success.
Geez, do you think you will actually get so-called consistent advice? On a forum? Corner chisels aren't an efficient means of doing what you need to--working on the show side of a piece. Heck, they are better suited to timber framing in my view (with the large versions, natch).
You should use the marking gauge or a ruler and marking knife to show you where the corners meet. You should then simply pare to those lines, being careful at the very intersection. You should work in from both sides of the mortise, being most careful on the show side where the tenons come through.
I typically pare from the side the tenon inserts first. I pare down to within a 1/2" or so from the show side. Then I flip the stile/leg or whatever so I can pare more carefully from the show side.
But I never, ever try to square up the show side of a through tenon without layout lines.
Take care, Mike
Thanks for the reply. I have been trying to make mortises and tenons for over 6 weeks. I have a home made jig that I really can't figure out how to use. I bought a Mortise Pal and I cannot figure it out. I cannot understand the directions. I have used an edge guide on a router and that always ends up not acceptable. My problem is I am not mechanically minded. I have to have a person at my side to show me. I sledom get the concept but by rote I can get it. I seldom have a person at my side and have determined that woodworking is beyond my abilites. I have tried for over 15 years to do it but I can see now that I just don't have it. To have peace of mind I will soon be having a sale. I guess this is the straw that broke the camel's back.
Thanks to everyone who has helped me in the past.
If it is "simply" a matter of having guidance, consider saving some bucks to take a class at a woodworking school near your location. They are so smattered around the country, one is near you. Try some of the local colleges to see if one has a woodworking class--they are usually very cost effective.
The fundementals of woodworking are just that, fundementals. With those basic skills a class will teach you, you can build on them with experience. Really do consider it.
It isn't really a matter of being mechanically inclined. It's more rote than anything--just like most skill-based activities.
For what it is worth, perhaps on this project you bit off more than you can chew. Don't fret about it. Scale back the projects, do more simply ones requiring less skill. Through mortises are more time consuming than blind tenons.
Even on this project you can elect to use a shorter tenon and cap the show side. Square up the show side to the best of your ability, make a slightly tapered "plug", a false through tenon that inserts up to your shorted tenon on the rail. By slightly tapering the plug, it will wedge against the pared sides of the show side of the mortise for a tight fit.
Take care, Mike
Sometimes people think that a highly engineered power tool is going to solve the problem in getting precision or reproducibility. And possibly in the hands of a skilled professional it would. Thjere is no substitute for hands-on expeience. I think that learning to cut these joints by hand initially is considerably easier and you will have the added benefit of understanding exactly what the principles underlying the joint are. While handcutting precise joints might appear to be difficult and only for the highly skilled, in fact these processes are just a series of discrete, logical steps. If taken step by step and if you pay close attention to detail, even a beginner will be able to execute a very servicable joint. I know this because I have taught many (1 day) dovetail and mortise and tenon workshops to complete beginners and see this happening all the time.
I just sent for a motise chisel and mortise guage. I am beginning to think this may be quicker once one gets the hang of it.
Thanks
FYI: consider the size of mortise you are going to be making before you buy the chisel(s). Sash chisels are great for smaller mortises. Sorby makes a really nice line of these and you can get them from Tools for Working Wood. For heavier mortises, the registered chisels that Marples makes would be good. And then there are the English pattern mortise chisels which are sometimes known as "pig stickers" (!) which are tanged chisels with very deep cross sections and and great for levering out mortises but not for the smaller ones. You want a chisel that is about 1/3 as wide as the thickness of the stock yoiu will generally be working on (1/4 to 5/16" for 3/4 inch stock for example). You can often find mortise chisels of any type on Ebay for a good price.
Consider the mortise gauge. The very best (and not necessarily the most expensive) are the "wheeled" gauges. Veritas makes a really nice one which is available from Woodcraft and Lee Valley, etc. So does Bridge City and Tite Mark but these are more expensive (but really useful). The scratch pin type gauges need to be modified slightly to work well. The points need to be filed more like blades than points.
Bonka,
Your 3/8" corner chisel would be suitable for a mortise routed with a 3/4" diamter bit. The wings need to register on a flat side of the mortise. The corner does the real work, not the wings. The tool you need, as someone else mentioned, is a mortise or firmer chisel.
Chris @ www.flairwoodwork.spaces.live.com
- Success is not the key to happines. Happiness is the key to success. If you love what you are doing, you will be successful. - Albert Schweitzer
An addition to Bill's last reply - There's an article by C. Becksvoort in the latest Fine Woodworking that demonstrates a rapid way to get square mortises using a forstner drill bit and a square mortise chisel. It's very clever, and it does work (I tried it), though you will need a mortise chisel with square-ground sides (i.e. not a tapered section through the blade, as the reproduction Ray Iles english mortise chisels are).
The Lie-Nielsen socket mortise chisels are made this way, and it's possible that some of the more recent sorby/marples offerings in the sash mortise chisel design are square in cross-section also, but I've no first-hand knowledge.
I have an Iles coming. A man told me years ago that he could be done with dove tails, dados and such with hand tools before I got the jig set up. That sounded like folly to me. Now I can see wisdom to that and other things he told me. I knew about everything back then. Now? Well I have learned to listen.
Thank you.
It's apple and oranges, for one offs the hand tools may be faster than the jig and power tools, a run of a couple hundred pieces the hand tool guy will starve.
If I have one piece to make I'll grab the hand tools and marking knife, a production run... I'll build a jig or fixture or set up a machine. Both have their place.
................................................
You can't wait for inspiration. You have to go after it with a club. Jack London
Yep me also..
As to the corner chisels.. GREAT for making the corner..
I finish up with my 'standard' paring chisels.
There are other reasons to use hand tools. For a hobbyist woodworker, there are considerations of noise, space and danger. That doesn't mean you can't give yourself a severe injury with a sharp chisel, but you're unlikely to lose a hand to a tenon saw.
For professionals that make antique reproductions, there is a matter of authenticity. 18th century colonial furniture made with power tools is very regular and smooth. While it may serve the purpose of storing clothes, providing a nice place to sit, or storage for letters and papers, repros made this way are very much modern furniture, and not much like the antiques they represent.
Good point. The processes are radically different and inevitably lead to significantly different results.
Bonka,
You never said whether you are using a left corner chisel or a right corner chisel. That's why there is no consistent advice.
Actually, consistent advice was banned on Knots two years ago.
Consistent advice is not a good thing. If you get consistent advice, you are more likely to use that advice without thinking, and that can be disasterous.
I have long held that the hardest thing to do on Knots is to be able to know which advice to consider.
My advice, which is the only advice you should take :-)
is that you never take advice without testing it out first on some scrap wood.
May you have a long and enjoyable woodworking life. If you want to do Mortise and Tenon simply, just buy a Festool Domino. No skill required. Just money.
Find someone nearby to show you about M&T. It is easier than reading about it.
Have fun.
Mel
Measure your output in smiles per board foot.
Dang! You never said whether you are using a left corner chisel or a right corner chisel. I thought all I had to do was change hands! BUT your are the scientist!
Were you this easy to get along with makin' rockets?
Edited 9/11/2008 9:42 pm by WillGeorge
Will George,
I wish I was making rockets. I was in Washington , DC, being a bureaucrat. While it is important to have bureaucrats taking care of the rocket makers, I am sure it is more fun to actually make the rockets and satellites. I was lucky to be able to work with some REALLY smart people at NASA, just like I do here on Knots.
MelMeasure your output in smiles per board foot.
being a bureaucrat.. No wonder you are so full of words!
I love it!
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