Replies

1. 
   pzgren | Mar 03, 2006 08:08pm | #1

   Doug,

      For me it falls into the "nice to have" category. If you are already pretty good at chopping mortises by hand, you probably won't need it -- any clean up can be done with a paring or bench chisel.

      If you're not so good at chopping mortises by hand, then you may find it useful, but after doing 20 of them, you'll probably be a lot better at it when you finish the last one....

     Sharpening: you can sharpen them by running the bevel on the top of the stone along the side edge -- works ok/so-so, as long as your stone has a 90 degree edge corner along the side. Normally, I used the flat of a square-edged slip stone; you just have to be careful not to slice your finger(s) up on the newly-honed chisel edge.

      Looking back on it, when I bought a corner chisel a couple of years ago, I was not very good at chopping mortises by hand. It was very useful then, but now that I am better at cutting mortises, I rarely use it. If I had it to do over again, I probably would not have bought one. But....hindsight is 20-20. Still a useful tool -- but, as I said above -- it now falls in the "nice to have" category.

   James

   
   

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   Edited 3/3/2006 12:08 pm by pzgren

1. 
   DougF | Mar 03, 2006 08:45pm | #4

   James, no question, perform enough of a single task and you'll get very good at it.  Thanks for you sharing your expereinces.  I don't mind spending $70 for a tool as long as it performs as expected. 

1. 
   AdamCherubini | Mar 04, 2006 05:06pm | #5

   Not to be argumentative, but I don't think this tool will perform as expected because I think you are mistaken both about this tool and this joinery. Yes they make small corner chisels today. But I doubt they did 100 years ago. So whatever style you are emulating, chances are that style was accomplished with some form of power mortiser. Also, just because they make a tool, say a swan neck mortise chisel for example, doesn't mean that tool was ever used successfully (or needed). The number and size of the mortises suggests you are making some form of mission or arts and crafts. That work was not done by hand which is the point that style. I can't think of a single case of joinery like this in 18th c work when we know for certain things were done efficiently by hand.So again, my concern is that what you are doing is unprecedented and that you are looking for a tool to make a difficult job easier. I think that's a set up for disappointment and frustration. That said, if the money isn't a big issue, it might be worth trying a corner chisel. What's the worst that could happen? But my advice would be to try a test with just your holes and a sharp 3/4" chisel and see how you do. I suspect with a little practice you'll find you won't need the corner chisel. Oh, and the trick to through mortises is chopping in from both sides. The problem you will encounter is laying out the penetration/scribe lines on both side due to the angle. You won't be able to use a gauge. Of course, if your holes were bored super accurately, you might be able to use them to help with the layout. Lastly, don't be afraid to undercut the inside walls of the mortise slightly. Leave the tenons long and chamfer the ends so you won't crack out the far side during installation. There are a couple non 18th c tools I use and really like. One is a japanese flush cut saw. It does a great job of sawing off those tenon ends. (be sure to wedge first).Good luck. I hope it all works out the way you want it to.Adam

2. 
   AdamCherubini | Mar 03, 2006 08:28pm | #2

   A couple things:

   I don't know how you will chop 3/4" mortises in 4/4 stock.  I suspect you're cutting them through the width and not in the edge.  In which case, I'm not exactly sure they are still mortises.  Maybe you should try dowells or something.

   Next, not sure I've seen many square mortises.  Sash mortises are sometimes square or very very small.  But sash are usually made from softwood, not hard maple.  So I'm not sure what you are making, but chances are, people didn't cut mortises in this material with corner chisels ever.  Corner chisels are carpentry tools used to square a corner of a mortise initially cut by boring a hole or series of holes with a framing auger.  They are a specialty tool and not a particularly helpful on in my opinion.  This is a job done just as easily with a sharp framing chisel (which is easier to sharpen).

   So here's my concern:  I suspect you are doing something non-traditional and wishing to use traditional tools.  Usually that's a recipe for frustration.  My recommendation is to either change your design to incorporate traditional joinery, or use the machines originally used to make the sort of item you are making.

   In either case, you won't need a corner chisel.

   Adam

   btw: cutting a square hole at a 10 degree angle with a chisel is one of the harder things you can do with a chisel.  So if (when) you pull it off, be proud of yourself! 

1. 
   DougF | Mar 03, 2006 08:42pm | #3

   This is traditional joinery and the through-mortises are in the sides and top of 4/4 maple stock and not the edges.  The through tenons will be wedged.  While corner chisels may be common in timberframing, they are also manufactured for cabinet joinery, thus my question.  I have bored the 10 degree mortises with a 3/4" bit but cleaning the corners at an angle through 4/4 finish maple is a chore.  Being relatively inexperienced at this type of hand work, although I do keep my chisels well-honed, I was curious if this tools would help me.

3. 
   rporcaro | Mar 05, 2006 08:15am | #6

   Doug,

   IMHO, forget the corner chisel. I think it's just as easy to square a corner with a regular bench chisel or maybe a mortise or firmer chisel. The corner chisel is being asked to knock out a substantial portion of wood and to do so very precisely. I've found that the chisel tends to twist or move out away from the corner as it is being driven. So it ends up being no more accurate than a two step approach with a more ordinary chisel. It probably would work well to square shallow mortises for hardware, but then it's really unnecessary for that too.

   But the biggest reason I have long since abandoned this tool (purchased as an "oh that looks like a good idea" tool) is that is a royal pain in the neck to sharpen. I've found it about impossible to get the two edges sharp, of equal length, and without a little remaining nib of steel at the vertex of the two edges.

   Good luck with the project and I suggest leave the corner chisels to timber framers or whoever. I never miss one for cabinetmaking.

    

    

4. 
   pqken | Mar 05, 2006 02:22pm | #7

   I have a corner chisel, don't use it much because it's a bear to sharpen. Trying to get the stone (or file) snug to the corner without touching the other blade is one of the harder sharpening tasks I've attempted. But then again maybe I'm just showing my ignorance.

5. 
   cowtown | Mar 06, 2006 07:27am | #8

   DougF...

   I cannot see what you need to do from up here, but it sounds like a balustrade encounter I had once upon a time.

   you gotaa cut 3/4" mortices at 10 degrees. If you can do this in the shop, you can purchase  morticing machines which can cut angled mortices. Much more difficult- I never did find one- to find one which will clamp onto stair stringers. Heck, I even mounted a mortice chisel on my 1/2" drill to do this on site, but while it worked in principle, I just couldn't apply enuf pressure to make it work in practice ( ain't exactly overweight)

   Perhaps you cannot do this on a dedicated shop machine, or perhaps you don't want to purchase a dedicated machine. Certainly you could invest a bunch of time like I did trying to find a "site" solution. Maybe you will have more success than I

    

   OTOH....

   The drilling and the chopping angle can be guided by simple guide blocks.

   If you can drill 3/4" holes at 10 degrees, you can actually drive mortice chisels by traditional mallet  and elbow-grease methodology. They ain't designed to do it, and the hammering is bound to mushroom both ends.

   And you may have to accept that you may have to put vicegrips on it and use a pry bar to extract it, if needed, but thats not a problem, at least you know the 3/4" is square and straight.....

   If you accept that this is indeed  a "sacrificial" chisel, the mushrooming at the driven end is a "no-care" situation, the mushrooming of the 4 tabs at the cutting end is almost a certainty and has to be dealt with, particularly if yer sacrificing a low-cost mortice chisel. You keep a cone-shaped sharpener (available through Lee Valley) to hone the inside edges, and you use a simple wet-stone to hone the outside flat again. With E Maple, you may have to do the outside every one or two holes, and maybe the inside every 4 or 5 holes, maybe not even at all.

   I realize that this is kind of a retro-concept, but it has worked for me in the past, and it cost me a whole bunch of time to fruitlessly research the normitic solution.

   Hey, you can always try it on a scrap or two to see if works for you.

   And when yer done, I betcha that mortice chisel, beat up as it may be, ends up in yer chisel drawer for the next time

   Eric in Cowtown