Mortice chsiels generally

[Anonymous]

I have often wondered why you never seem to see mortice chisels much wider than 5/8" or 3/4" Does any one know why is this? :-s. Apart from those hand made american ones where the maker (I forget his name) retired recently I think he made up to 1" ones??, 3/4" was the widest I saw. Curiousity (no, ignorance!) on my part really

 

[Lord Nibbo]

I have often wondered why you never seem to see mortice chisels much wider than 5/8" or 3/4" Does any one know why is this? :-s. Apart from those hand made american ones where the maker (I forget his name) retired recently I think he made up to 1" ones??, 3/4" was the widest I saw. Curiousity (no, ignorance!) on my part really

3/4" is pretty big, any bigger you would need a lump hammer to whack it with.

 

[Alf]

Yeah, too blooming big to use would make sense. Also, what's the largest practical width of a mortise before it makes for better practice to do a double M&T anyway? :-k

Cheers, Alf

 

[Anonymous]

Try using a 1/2" chisel in Ash. I have to beat mine pretty hard to cut a mortice that wide and would hate to try a 3/4 :shock:

 

[Scrit]

Try using a 1/2" chisel in Ash. I have to beat mine pretty hard to cut a mortice that wide and would hate to try a 3/4 :shock:

Ah! You obviously need a bigger mallet.

Scrit

 

[Sgian Dubh]

Scrit, the proper saying in my circles has always been, "Don't force it! Just use a bigger mallet/hammer/sledge." Slainte.

 

[MikeW]

Yeah, too blooming big to use would make sense. Also, what's the largest practical width of a mortise before it makes for better practice to do a double M&T anyway? :-k

Cheers, Alf

Suppose it depends on what one is trying to make. For instance, a trestle table I once did had a 1" through tenon, but still used a 1/2" mortise chisel to near the gauged lines and then pared to them using large paring chisels.

For myself on non-through tenons, the largest I've done before splitting them into two tenons is 3/8" and there was 3/16" between them and about 3/16" shoulders.

Take care, Mike
who sizes mortises based on his largest hammer and the amount of effort he desires to expend... :lol:

 

[jasonB]

Yeah, too blooming big to use would make sense. Also, what's the largest practical width of a mortise before it makes for better practice to do a double M&T anyway? :-k

Cheers, Alf

I used a 40mm chisel for these But it was an Axminster all steel one driven with a copper/hide 2lbs mallet.

Jason

 

[mahking51]

jasonB,
Nice picnic table! Suitable for a man of my proportions. :lol:

When I was working on the first Harry Potter film they were building one Quidditch Tower for real in 14" Oak beams, all pegged M&T's. The chippies were making very hard going of it with routers burning out all the time so they were mostly done by hand and it became a kind of macho game to see who could drive the biggest chisel. In the end Warner Bros just hired 60 more chippies to move it along a bit. I am not kidding you!
Regards
Martin

 

[Anonymous]

Nice frame jason I never knew you were into that side of wood working
Was that oak, or chestnut you used? What method did you use to scribe and line the timbers did you go off a full size floor rod? Any particular reason why you didnt do english tying joints and dropped the tie beams, or put some braces on the wall plate/posts? Were you restricted by available timber supply for a decent jowl post? Thats a problem Im facing now I probabaly seem like a pestering kiddie asking so many questions but I find the whole framing thing extremely interesting, I build my own shed frame strting soon 8-[

The reason I ask about mortice chisels (thanks for your replys!) is because I often wondered why timber framers havent used bigger ones to do 1 1/2" or 2" mortices rather than use drill auger or bit or boring machine then pare up etc etc
Aparently german framers had to cut a mortice in less than 8 minutes entirely by chisel no drilling first; how do they do that? You must be loking at some sort of hefty strong mortice chisel isnt it? Or was it a 2 man job-one holding the chisel the other striking with a maul?
Do any german woodworkers know about this? I find it extemely fasinating to discover how these things shiould best be done
Cheers Mr Spanton

 

[dedee]

I find the whole framing thing extremely interesting, I build my own shed frame strting soon

Another timber frame project, there really is something in the air.

Please try and post some WIP photos when you get started.

Andy

 

[Anonymous]

Hi dede

Is thetre others who are doing traditional type frames as well?
No disrespect to people who built a shed or shop from 4x2 etc, but with my one I wanted to follow tradition espcially local vernaculur traditions. I was looking inside an old forge today part 1750, part 1795, it looked pretty much like what I have in mind for my project except I'll have some insuation in it (theres no emocticon thingy with a little woodburning stove and a pair of hands rubbing together!!)

 

[Sgian Dubh]

mr. spanton, given what you said (in the post I'm replying to) about building in the vernacular tradition my assumption is that you'll be mostly using either green wood at about 28% MC or over, and air dried wood at perhaps 18% to 22% MC.

My guess is you'll be looking for the joints you create to self tighten due to differential shrinkage in the parts as moisture moves out of the wood. It's similar to the principles used in Windsor chair making.

I'll admit that timber framing is not my particular field but cutting and shaping green wood or air dried wood is considerably easier than working wood kiln dried to 10% (here in the UK) and, in the US, wood kilned more commonly to about 6% or 7%. The drying stiffens and hardens the wood a great deal.

So, if you've got some hefty mortices to work and chunky tenons to incorporate, and assuming you can find some stout wide mortice chisels-- Ashley Isles might be a source, then working relatively wet wood should make life bearable.

Still, as before, to avoid unnecessary force, you still might need to use a much bigger mallet (sic) ha, ha. Slainte.

 

[Scrit]

Still, as before, to avoid unnecessary force, you still might need to use a much bigger mallet (sic) ha, ha. Slainte.

I was taught to use progressively bigger mallets on progressively bigger mortise chisels - partly to impart more force to the chisel - hence my earlier comment. My bigest mallet is a 7in one, but I have seen bigger.

You'll get a greater impact by using a steel hammer, but your chisels will tend to chip out more readily and the end of the handle wil end up cream-crackered in next to no time, even with the "registered" style of handle.

I've seen framing done in the USA and Germany with solid steel chisels like those Jason B mentioned. Tried a bit myself, and as Sgain Dubh says green oak cuts quite easily providing your tools are sharp (and they go black in a matter of hours from the tannin and sap, as do your hands), but in both countries mechanised, hand-powered boring machines have been in use for at least 130 years and power tools are the norm today (commercial pressure, again). For an idea about what the Germans use, take a look at the Maffell web site.

Scrit

 

[jasonB]

Mr Spanton, i'm off to work now but will reply later, possibly worth starting a new thread?

In the mean time you may enjoy this

J

 

[Scrit]

Jason

That's what I call a mallet:

Scrit

 

[Anonymous]

Thanks for your further replies gentlemen
No problem should you wish to start a new thread jason, my fault for getting side tracked anyway :wink:
I reckon what you siad about mallet size scrit is a bit like when you use progressively bigger/thicker screwdrivers for fatter screws? Matching tool size to the job in hand. The mafell site has power tools aplenty but for my purposes I wont need to invest in a chain morticer. Its just that I heard somewhere they traditionally had to be able to chop a big full mortice entirely by chisel in less than 8 minutes before completing a german aprenticeship :shock:
I've seen all metal chisels in France but never thought they were mortice ones as they seemed like bevel edge ones? Youd certainly be able to thwack them and if you got them longer and stronger youd get some good leverage too? Just another thought I wonder if they had anything like a massive swan neck lock mortice chisel to clean out bottoms of drilled mortices?
Have you ever done any windsor chairs/gibson or hedgrow chairs sgian; are you Irish?
cheers Mr Spanton

 

[Scrit]

I reckon what you said about mallet size Scrit is a bit like when you use progressively bigger/thicker screwdrivers for fatter screws? Matching tool size to the job in hand.

Yes, that's right.

I heard somewhere they traditionally had to be able to chop a big full mortice entirely by chisel in less than 8 minutes before completing a German aprenticeship :shock:

Maybe for the apprenticeship, but I'd bet that you won't see that technique being used on a job site. I can recall seeing woodcuts of timber shipbuilding where it looks as though the mortises are being hogged-out with an auger bit first before the chisel is applied.

I've seen all metal chisels in France but never thought they were mortice ones as they seemed like bevel edge ones?

But green wood will need more clearance to get your chisel out - same as bandsaw blades for working green timbers need a much greater set to cut smoothly without stalling in cut

Just another thought I wonder if they had anything like a massive swan neck lock mortice chisel to clean out bottoms of drilled mortices?

Why bother cleaning them out at all? It's not as though they're glues and the dowels are what really hold the joints closed. The only roof I've ever worked on like this was on my last house about 20 years ago. Built 1605 with "Yorkshire greys" (cleeved stone "slates") and not maintained for 40 or so years whicjh meant the slates had to come off, new ridge poles go in and some of the roof timbers needed to be replaced. Both the joints and the bottoms of the mortises were as rough as anything. The mortises were straightish, but not necessarily square or consistent depth! But the timbers weren't straight either with a lot of natural curvature in the larger pieces. The biggest help in straightening things up was the slick which seemed to get used everywhere (two-handed without any mallet - the photo is the nearest I could find):

BTW I was the labourer to a traditional roofer so most of what I did was humping stones, timber, etc up and down scaffolding. The guy I employed (a Pole who'd been here since WWII and had trained in this area) used a 10in or so wide Makita planer to make his flats and cut his tenons with German-style frame saws with fleam teeth (they cut both ways). He used power auger bits to drill his joints (in an oversized electric drill) with all-metal chisels and a lump (club) hammer to clean out the mortises and finally a #10 plane and the slick to clean-up and redimension where needed. And he was really fast, too, but the surprise was how few tools he actually needed and how big they were.

Scrit

 

[MarcW]

For myself on non-through tenons, the largest I've done before splitting them into two tenons is 3/8" and there was 3/16" between them and about 3/16" shoulders.

Take care, Mike
who sizes mortises based on his largest hammer and the amount of effort he desires to expend... :lol:

I saw once a japanese double mortice chisel in David's first book or was it T. Odate and am wondering how it performs. Anybody has worked with or knows where to buy? I checked but without success.

Glad if someone could help,

Marc,

Being aware that this is a very specalized chisel but worth trying it

 

[Derek Cohen (Perth Oz)]

The largest mortice chisel I own is a 1/2".

Using the 1/3 rule, a single mortice/tenon joint would be appropriate for a 1 1/2" wide stretcher (which is Wide). For wider than this, I assume that most would just use a double mortice/tenon joint, which would make this width chisel good for a 3" wide stretcher (which is Huge!).

Regards from Perth

Derek