Registered mortice chisels not square.

[Fat ferret]

I use old registered mortice chisels for nearly everything chisel related. The ash handled iron hoop type you can get new from various makers (crown and expensive) but mine are old Marples, Ward, Toga and Sorby I think.

They are mostly fine. Good steel and very strong but I've come across a couple where the blade isn't rectangular in profile. One Marples was a parallelogram and one Toga was much narrower at the cutting edge than the other edge, you know the one with the logo on it. What's that about? Seems like a pretty basic error when they are otherwise well made. Makes for messy mortices and they are unuseable to me.

Obviously I will just ebay them on, after all someone else obviously did but anyone found this themselves or got any idea how this happens?

 

[Jacob]

The trad design is much more subtle than it looks. They are supposed to be tapered in cross section - wider at the face than the back. This taper means that when you lever the chisel forwards a touch it will be loose when you lever it back so you can pull it out more easily for the next cut. If it's rectangular in profile you lose this advantage.
The one narrower at the cutting edge must have been "modified" :roll: and should either be sharpened the other way round or binned.
Another subtlety is the rounded bevel - not only easier to sharpen but also gives maximum leverage if you are trying to clean up the corners of a blind mortice - a design detail you find with other levering tools; claw hammers, wrecking bars etc. A straight claw on a clawhammer is useless.

 

[Fat ferret]

Good point Jacob, the narrower cutting edge could have been ground the wrong way at the factory it's close to a whole mm wider at the back but I have two 3/8ths and always use the other one. It doesn't look modified. Good idea about grinding the other way too, which would fix it unless its laminated which doesn't seem likely, never thought of that.

The parallelogram one is awful though. It's latter day Marples.

Yes I knew about the idea that they should be lightly wider at the cutting edge and it makes sense I haven't checked the ones that look okay and work well but I suspect that's the case with them.

I've tried your rounded bevels despite being taught the other way and being happy with that. I like the idea of not needing to grind. I get your arguments that it might make a better shape for morticing. But for me it takes too long to get a wire edge on the bigger chisels with this method. I'd be there all day with my 1 1/4 hard as anything Marples. So I just hollow grind but stop short of the edge and hone on oilstone. Strop on hand and away I go. Otherwise you have to remove a lot of metal by oilstone which is time consuming. For the smaller ones I have tried your rounded bevel but for 3/8ths or less I can just hone with one bevel right across because there's not much metal to go anyway. I've tried it and it doesn't work for me, if it does for you then I'm happy for you .

Anyway thanks for your reply and good idea about the Toga chisel regrind.

 

[Fat ferret]

I don't need a rounded shape to lever blind mortices clean. I just chop until the waste is small enough to come out by itself and leave a bit of dead space as the glue won't do much with the end grain of the tenon anyway.

 

[Dovetaildave]

Good point Jacob, the narrower cutting edge could have been ground the wrong way at the factory

Ha Ha Ha good one ....
Mebby they could have marketed it as "Underhand mortising"....or even "left-handed mortise chisel" :lol:

Does it have anything printed on the blade (Branding or sizing) that may signify the front/ honing side?

On a slightly more sensible side, when I was in site work back in 80's our head chippy laughed at my hollow grinds and asked me where i'd get it done on site, from then onwards I round beveled as the other chippys did ..........till I became a joiner in a workshop with access to a 8"grinder :wink:

 

[Cheshirechappie]

It might be worth noting that there's a difference - albeit subtle - between mortice chisels and registered chisels. The former come in two forms; the old oval-bolstered mortice chisels - the heavy duty ones with big oval-section handles (sometimes called 'pigstickers' in North America), and the lighter sash mortice chisels, having a blade nearer square in cross-section, and originally intended for lighter work on the the smaller mortices found in sash windows. Registered chisels are not really intended as dedicated mortice chisels, they were intended as heavy duty general purpose chisels having the sides ground square to the front and back - hence the tern 'registered' - it refers to the square sides. They certainly can be used for morticing, though they lack the clearance that the tapered cross-section of oval-bolstered mortice chisels. They were pretty much universally fitted with large, double-hooped handles, the hoop at the mallet end being a reinforcement to allow for abuse with lump hammes and the like. Registered chisels were favoured by the heavier trades; millwrights, railway wagon builders and the like.

Back in the day, almost all Sheffield (and Birmingham - Brades for example) chisels were ground by hand, and it seems that the odd one or two escaped quality control. I'd suggest that the mis-shapen ones are examples of such rogues, and without regrinding the edges, there's not much can be done about it. Most of the registered chisels I've seen were solid tool steel, so regrinding to transfer the cutting edge to the other side would be possible, but a slow old job. Grinding a blade square would also be possible, but would need a light touch and preferably a very wide wheel to keep things straight.

Checking whether a chisel is laminated is quite straightforward. If the blade is cleaned up, it's usually easy to see the join between toolsteel and the softer backing steel (in older chisels, wrought iron is more likely than steel). Failing that, apply a small file carefully. If it cuts any part of the blade easily, that part is soft, and the chisel is almost certainly a laminated one.

 

[bugbear]

Checking whether a chisel is laminated is quite straightforward. If the blade is cleaned up, it's usually easy to see the join between toolsteel and the softer backing steel. Failing that, apply a small file carefully. If it cuts any part of the blade easily, that part is soft, and the chisel is almost certainly laminated.

You can also work the bevel using a fairly coarse abrasive - Norton India "fine" or 120-180 grit SiC work well.

At this level, the different resistances of the hard and soft metal result in a clear visible difference in the ground texture, easy to see.

BugBear

 

[Jacob]

I've had a few old reject chisels marked as such by a line filed through the maker's logo.

 

[swb58]

Whilst on the question of chisels and tapers can I ask a question please? Is there a name for a chisel which tapers from the cutting edge, being narrower at the handle end? Thanks.

 

[AndyT]

Whilst on the question of chisels and tapers can I ask a question please? Is there a name for a chisel which tapers from the cutting edge, being narrower at the handle end? Thanks.

I'd call that a fishtail, especially if the taper was really just at the cutting end. As far as I know it's a pattern only used for carving.

However, a taper along the whole length used to be the norm in the seventeenth century or earlier as illustrated in Moxon and other earlier texts.
It's still favoured in some countries - Rutlands used to sell a line of Chinese chisels which tapered like that.

 

[Trafalgar]

Sounds like whatever registration they have should be revoked. :lol:

 

[swb58]

Whilst on the question of chisels and tapers can I ask a question please? Is there a name for a chisel which tapers from the cutting edge, being narrower at the handle end? Thanks.

I'd call that a fishtail, especially if the taper was really just at the cutting end. As far as I know it's a pattern only used for carving.

However, a taper along the whole length used to be the norm in the seventeenth century or earlier as illustrated in Moxon and other earlier texts.
It's still favoured in some countries - Rutlands used to sell a line of Chinese chisels which tapered like that.

No, this is an equal taper along the full length. 2 3/16" at the edge, 2" wide at the top (5" length). It's a Marples Hibernia

 

[Cheshirechappie]

Whilst on the question of chisels and tapers can I ask a question please? Is there a name for a chisel which tapers from the cutting edge, being narrower at the handle end? Thanks.

I'd call that a fishtail, especially if the taper was really just at the cutting end. As far as I know it's a pattern only used for carving.

However, a taper along the whole length used to be the norm in the seventeenth century or earlier as illustrated in Moxon and other earlier texts.
It's still favoured in some countries - Rutlands used to sell a line of Chinese chisels which tapered like that.

No, this is an equal taper along the full length. 2 3/16" at the edge, 2" wide at the top (5" length). It's a Marples Hibernia

Might be a Sash Pocket Chisel, used in cutting the slots to feed the weights through in sash frames. They tend to be wide, but with very thin blades. Here's one - https://www.pinterest.com/pin/393642823654355334/

 

[Fat ferret]

Sounds like whatever registration they have should be revoked. :lol:

Too right. Had a better look it's trapezoidal at the cutting edge but further up it's a parallelogram! Total waste of time.

Interesting about the different chisel types. Here are mine, they do cut mortices fine. https://flic.kr/p/tQWmQ7 I only really use the 4 bigger ones. Most of my mortices are 1/2", 5/8", 3/4" or 1" so I don't use the smaller ones much but nice to have. I haven't seen the larger sizes in pig stickers or socketed mortice chisels. Do they exist in say 3/4"?

 

[Fat ferret]

Good point Jacob, the narrower cutting edge could have been ground the wrong way at the factory

Ha Ha Ha good one ....
Mebby they could have marketed it as "Underhand mortising"....or even "left-handed mortise chisel" :lol:

Does it have anything printed on the blade (Branding or sizing) that may signify the front/ honing side?

On a slightly more sensible side, when I was in site work back in 80's our head chippy laughed at my hollow grinds and asked me where i'd get it done on site, from then onwards I round beveled as the other chippys did ..........till I became a joiner in a workshop with access to a 8"grinder :wink:

Just Toga Sheffield on the bevel side.

 

[Biliphuster]

I don't use the smaller ones much but nice to have. I haven't seen the larger sizes in pig stickers or socketed mortice chisels. Do they exist in say 3/4"?

I have a 3/4" pigsticker which I had to rehandle. I have seen them go up to 1" but never more than that. Past that point you would probably go with a socket framing chisel, unless you took the sensible option and just bored out the mortice and pared the walls.

 

[Jacob]

Yes I imagine that above 3/4" they would begin to need such a huge belt with such a huge hammer that your sensible option becomes unavoidable!
On the other hand they were quite common in very small sizes down to 1/8" but with the wide blade just like the bigger ones. Bit of a mystery as obviously nobody does 1/8" tenons. My guess is that they were used probably by people making machines, boats, vehicles, clocks and other technical apparatus which used to combine wood and metal in interesting ways. There was a lot of it about.
I've had a go with some and they are very effective in cutting a deep 1/8" slot along the grain. In fact I can't think of anything else which would cut a precise slot which is deep, narrow and with closed ends.

 

[David C]

There were some specialist trades such as wooden camera making which used very fine joints.

Not sure if they were tenons or bridle joints.

Jim Kingshott used to do this stuff.

best wishes,
David

 

[Cheshirechappie]

Oval bolstered mortice chisels were made in sizes from 1/16" (very rare and collectable) to about 3/4" (also quite rare). The commonest sizes seem to be from about 1/4" to 1/2" (which covers the bulk of furniture and joinery work).

Socket chisels such as this one - http://www.secondhandtools.co.uk/ww71en.html - have been around for a long time (Benjamin Seaton had a set in his toolchest dating from 1797), went from about 1/8" to well over 1" - I've seen the occasional 1 1/2" on Ebay. Most are laminated, so beware of really short ones - it's possible to use them past the steeling. They seem to crop up quite a bit on Ebay, and not for outrageous prices, either. Sizes like 5/8" and 3/4" are quite common. Some have hooped handles like the one shown in the link, but most just have a plain, sometimes very short, piece of wood. Sizes do tend to be a bit 'nominal', so something stated as 3/4" might be a generous 1/32" full or bare.

Edit to add - Here's another example (bit better picture) - http://www.jimbodetools.com/7-8-x-15-in ... 43716.html

Marples were still making these in 1938 (well, they were in the 1938 catalogue, anyway!) in sizes from 1/4" to 2".

 

[AndyT]

Here's a couple of action shots of a 1/8" mortice being cut in 3/8" thick stock

(from https://www.ukworkshop.co.uk/forums/post959573.html#p959573)

The chisel I used is a nice delicate thing, but swells to about 1/2" deep. I have a couple of deeper section chisels but you soon run out of room unless your mortice is very long.