Est. 1998 — 27 years of woodworking knowledge
Adam's chisel technique
John Hoffman
>A little advise please. I have been trying Adam's shoulder chisel technique to make a mortise. Been practicing in pine and can not avoid tearout which does not make a nice mortis wall. Only scored one side like Adam suggested and am wondering is this just one of those need more practice situations or is there more to it that I need to know?
Thanks
Re: Adam's chisel technique
Joe Rogers, Northern Virginia
>John...My guess is the choice of wood. Pine is extremely hard to work across grain and tends to crush. It has very different hardness early and late wood. This could account for your difficulties. Try a hardwood and compare your results. If the results are the same try refining your sharpening process.JR
Re: Adam's chisel technique
Brent Smith
>John...As Joe said,it's important to have a properly sharpened chisel for this technique.
But,it also takes a lot of practise to get it working right.Try using walnut as a practise wood.It's hard enough not to crush and easy enough to work.
Brent
Re: Adam's chisel technique
john in KS
>Where can I find the article on this technique? Is it in a book I have to buy or can it be found online?
Thanks,
John
I don't get it
Adam Cherubini, NJ
>Hi John,
Sorry you are having trouble- not sure I understand what the problem is? Using a proper mortise chisel (one with tapered sides through the thickness)you simply pare material away. The first cuts are a series of shallow cuts into the wood, not a long pare. You shouldn't be getting tear oput or anything like tear out.
Beyond that, you may have to accept what you get. I'm not sure what your expectations are. Pine mortises nicely, in my experience. Using this technique, my side walls are about 10 times nicers than paring the walls vertically, which sometimes "log rolls" grain out. But the final result doesn't look machined or anything. Probably not as nice as a hollow chisel mortiser (not sure as I've never used one).
If you are still having problems, send me an e-mail.
Adam
Re: I don't get it
Pam Niedermayer - Austin, TX
>Hollow chisel mortisers do produce pretty nice sidewalls, but the bottoms are ugly in the extreme. And then there's all that extra sharpening (two tools instead of one) and the limited availability of sizes. And then we get into cross vises and various jigs. All in all, a major waste of time and money.
Not sure what you mean by "paring the walls vertically." If you mean paring the sides after chopping, there's no requirement for doing this. In fact, I never do, always go with the main chisel cut and let the rest take care of itself.
Pam
Re: I don't get it
Joel
>There are two reasons for intentially leaving a tiny amount of material for paring after chopping the main mortise:
1) it's easier - no need to worry if the mortise chisel is in exactly the right place- you can hold the chisel at the handle and position it quickly and chop even faster. The paring operation is trivial and takes seconds.
2) You can create mortises to whatever exact width you want - so it's easy to do mortise or tenon first (whichever is faster) and gauge the mortise exactly for a vacuum fit (not for the 1/16" interval of tool width) (which is overkill but when I studied if a mortise wasn't smooth enough in the joint to go in an out with a pop - I had to do it over again). not important really for blind mortises but for though mortising you want that perfect fit easily and quickly. But you do want a pretty good even fit for all mortising - escpecially if you use hide glue - liquid of solid. For deep mortising theres an even bigger benifit.
Finally - it's actually historically accurate. It's how Moxon describes his mortising. First chop like a demon to depth and then pare for exact sizing. Figure with a little practice 3/4" mortises in oak- including the paring - under 3 minutes per (faster I guess if you do it all day for a living).
Also in just thinking about it - you don't need particually sharp mortise chisels which means less maintance on the tools.
note: I am working on transcribing the mortising section of Moxon into modern English and type - I'm about 1/2 done should have it available in a week or two - maybe three. He talks about layout, chopping, paring and then doing the tenon. It's actually a description on housebuilding - in general he never talks much on furniture, where the joints are smaller and easier.
Softwood vs. Hardwood...difference? I dunno.
Luke Herzberg
>John, I work mostly with fir and it is really critical with this technique to pare in the grain-friendly direction, just like planing. It dislodges great heapin' chunks of wood pretty quickly to pare the wrong way. Because of the high variation in the hardness of the wood as you pass through grain line, I find it helps to define the mortise sides with the chisel until you are at sufficient depth (could be 1/8" or better)that it will guide itself. Otherwise, the grain can skate you right out of your pencil (or even marking knife) line.
I also find myself holding the chisel in a variation of Adam's stance, with the left hand in it's usual place, but the right hand turned inward, palm up, and the butt of the chisel more in the center of my chest than on the shoulder.
YMMV...
Scott in Douglassville, PA
>All in all, a major waste of time and money.
Maybe for you, but
Like I said, YMMV - I prefer to spend my time on planing and tweaking joinery, so it works for my habits, and was decidedly not "a major waste of time and money".
Scott, loving the smell of narrow blanket generalizations in the morning
Re: YMMV...
Pam Niedermayer - Austin, TX
>Sure, mileages vary. I loved the hollow chisel mortiser first couple of times I used it, then started running into some issues. So I replaced it with a Barnes foot operated version which uses bits that look like mortising chisels.
Pam
Note: I haven't actually used the Barnes yet, it's waiting for the new shop.
Re: I don't get it
Pam Niedermayer - Austin, TX
>Don't know, Joel, too much dribbing and drabbing for me. I prefer going with the chisel size, makes layout and fitting trivial.
Pam
Here you go ... *LINK*
Clay C in Miami
>John,
It's in the 'Hand Tools' part of the 'Articles' section right here on WC!
Direct link below ... though, if you didn't know to look there, you're missing out on lotsa good stuff - go, and wander through the articles. Every time I refer back to one, I end up spending a half-hour reading new ones.
Cherubini On Mortising
The Barnes: Is it one like this? *LINK*
Greg B�tit
>Does it have a hardwood spring?
Barnes mortiser
Ya gotta *love* the feet!
Greg B�tit
>
Maybe a dumb comment, but...
Bill Houghton, Sebastopol, CA
>How's your sharpening technique? Softer woods like pine call for VERY sharp chisels, because the cellular structure is weak enough that you can crush the wood fibers more easily. I recall reading somewhere once that paring end grain on pine is an ultimate chisel-sharpness test.
Thanks Clay!!!!
John in Ks
>
Re: I REALLY don't get it...
John Aniano, somewhere in central NJ...
>Hi Adam,
Has anyone asked you this question about your mortising technique? - I have no doubt that it does indeed work, but then why are there so many "pig sticker" chisels around with unbelievably massive handles? If you were simply paring the mortise with minimal hammer blow pounding, why then the need for an oversized bolster and handle?
I've seen you demonstrate this technique when you spoke at the CJWA (say, when will you be speaking AGAIN at one of our meetings??...) a few years ago. I can't disagree that the method works, I'm only questioning aspect of the tools that doesn't seem to jive with the technique.
I recently used a 1/4" wide pig sticker chisel in what I�ll term a "massive pounding mode" to cut six blind 2.5" wide mortises in pine, and none took me much more than 5 minutes each. Each pounding took the blade maybe 3/8� deep into the pine so I only had to go about 4 rounds per mortise to get to the depth I needed. Yes, the sidewalls were not "crisp" but, hey, they held the tenons very well and that's what counts. I found that the ~30 degree blade held up well without needing sharpening and the fact that the blade has a curved �bezel� seemed to make the cuts easier to do. Maybe it�s my imagination, and not having seen the original Maxon text, I always thought that these tools were meant to be pounded. They certainly work in that mode�
One more thing, I�ve watched T. Odate make wonderfully crisp mortises using the Japanese version of mortise chisels and he uses a �pounding� method � maybe not the �massive� version I employed�
Just my $0.02 worth, and sorry for questioning�
John
Re: The Barnes: Is it one like this?
Pam Niedermayer - Austin, TX
>Not exactly, it looks like the one below from the 1896 catalog. Couple of issues since the previous owner had attached an electric motor (still foot activated), may have to find/make a couple of parts.
Pam
Mortise chisels and bolsters. Drifting OT. Long.
Angus Barclay, in New Zealand
>I'm not Adam but I'll chime in with my very limited experience of successfully using his mortising technique . . .
Question 1 - Why do so many pig sticker chisels have massive handles?
Question 2 - Why the need for an oversized bolster and handle?
Answer 1 - The technique worked for me partly because the handle on my pig sticker is so large and shaped the way it is. The very large butt end of the handle with its slightly rounded edges distributes the pushing force across a large area of the hand and allows use of considerable pushing force without any discomfort. The slight tapering of the handle fits the hand very well. The oval cross-section of the handle allows easy and accurate alignment of the chisel (and resulting mortise walls) by feel without needing to eyeball the timber or the tool.
Answer 2 - I have no idea why the bolsters on pig stickers are so large.
Pure guesswork: A pig sticker's large bolster transfers force from handle to blade and stops the tang being driven into the handle and splitting it. Ferrules seem an inferior design to do the same thing (but probably cheaper to manufacture). Sockets avoid the issue by making the handle try to split the blade instead but likely cost more than bolsters to manufacture. Witherby, Buck Bros, Swan, Bergs, Stanley etc had to make and sell these things for a profit and all three ways of connecting handle and blade have pros and cons from design, engineering, manufacturing and marketing angles. Huge bolsters probably aren't needed to cope with the forces generated when not using a mallet, so maybe their size indicates that pig stickers really were designed to be whacked sometimes. Or maybe they were just a marketing gimmick that became as sucessful as the bedrock plane frog. However, it is interesting to note that some mortise chisels with relatively smaller bolsters than pig stickers back up the bolster with a ferrule too. This belt and braces approach could indicate that bolsters really do need to be large to be effective on their own - maybe even the size they developed into on pig stickers.
regards
Angus Barclay
(recent convert to Cherubuni mortising technique)
Re: Mortise chisels and bolsters. Drifting OT. Lon
Joel
>I happen not to agree with Adam's reading of Moxon and I belong to the whack it has hard as you can school.
THe reason the bolsters have to be so big is that when you drive a mortise chisel 3/8 or more into wood (oak) and pull the strongest part of the handle is in the wide dimension of the oval handle - which is why they go to the trouble of making an oval handle - comfortable yet strong and easy to align in your hand.
But pulling on the handle transfers all the force to the tang and bolster. If the bolster was smaller the handle would have less to push against, force would have less to distribute against, the wood would get presses in, and you would start getting play in the tang and the handle would eventually fail.
THose guys of 200 years ago knew what they were doing - if you mortised all day - which they did - you develop really efficent tools.
