A new pig sticker, or the hidden costs of walking to work...

[Eric The Viking]

I ground it last night. My bevel measure (notches in a bit of plastic, courtesy Dakota) isn't wonderful, but it was at 30 degrees. I've gone a bit steeper, probably 33. That gets me in the ballpark, and I'll round it a bit (aiming for 35) when I hone it, next time* I've got the big glass plate out for a scary sharp** session, probably next week.

One other plus about a rounded bevel (thanks Jacob!) is the extra meat left behind (the primary bevel otherwise is a chord), but it'll get there with subsequent regrinds - I'm not taking any unnecessary metal away as it's old and nice. I reserve the right to change my mind if it doesn't behave.

E.

*It's tidy-the-house-up week. I'm a man under Authority!

**just because I use wet+dry on glass doesn't mean I can't freehand stuff if necessary, but you do have to be careful not to scuff the paper. It's a quick and easy way of going from coarse to fine grit, and I get on well with it.

 

[Vann]

But there's no rule...

Correct, but people come here for guidance. We don't all have the knowledge you have gained by working with these tools for a living.

...what works is what counts.

But without guidance where do we start? 20°? 25°? We'd loose a lot of good steel before we got to a stable 30° or 35° without edges crumbling.. That's why we come here to get advice. Unfortunately you're so busy pushing your rounded bevels, you forget to give the advice the OPs needs. You know roughly what works, we don't necessarily. Try not to forget that.

Cheers, Vann.

 

[Jacob]

....t without guidance where do we start? 20°? 25°?

30º. Try not to forget that.

If in doubt just stick to the time honoured rule of grind at 25 and hone at 30. This has been repeated by just about every woodwork book and woodwork teacher probably for thousands of years and is good practical advice for the beginner.

NB I'v never had "crumbly edges" myself. In fact I'd never heard of them until people started complaining about LN chisels and A2 steel.

 

[dannykaye]

Never sure what makes a pig sticker, my favourite mortice chisel is a W Marples & Son. Sadly in need of tlc after three years in a box in a shed but... The primary angle is 25 and the cutting edge is 32.5, according to a Richard Keil gauge.

the end of the handle is three leather pads. If anyone has any of this pattern they want to get rid of please PM me as I would like a 1/8 and a 1/2. I could be persuaded to swap for more rugged versions

 

[Peter T]

....t without guidance where do we start? 20°? 25°?

30º. Try not to forget that.

If in doubt just stick to the time honoured rule of grind at 25 and hone at 30. This has been repeated by just about every woodwork book and woodwork teacher probably for thousands of years and is good practical advice for the beginner.

NB I'v never had "crumbly edges" myself. In fact I'd never heard of them until people started complaining about LN chisels and A2 steel.

Ray Iles English Patern Mortise Chisel. ........... English Oak. ..........

Crumbles at 30 degrees, lasts forever at 35 degrees!!

 

[Eric The Viking]

Never sure what makes a pig sticker, my favourite mortice chisel is a W Marples & Son. Sadly in need of tlc after three years in a box in a shed but... The primary angle is 25 and the cutting edge is 32.5, according to a Richard Keil gauge.

the end of the handle is three leather pads. If anyone has any of this pattern they want to get rid of please PM me as I would like a 1/8 and a 1/2. I could be persuaded to swap for more rugged versions

Can't help on the swaps, although the leather pad idea is 'mentally bookmarked'. It's a sort of woody version of a Thor hammer. On which note, I see Axminster sell replacement pads - would be dead handy for mine as the leather is quite shrunken now, but I can't imagine how you fit them - anyone got a tried and tested technique?

Sorry - drifting my own thread! Feel free to do a handbrake turn...

E.

 

[marcros]

have a look for a thread on rehandling stanley 750's. I am almost certain that i have seen a few things on replacing the leather washers. I have some stanley socket chisels that are not 750's (they are defiance I think, marked Stanley D Made in USA) that had the same washers on. They will be rehandled one of these days, when i get a few more.

 

[Cheshirechappie]

Never sure what makes a pig sticker, my favourite mortice chisel is a W Marples & Son. Sadly in need of tlc after three years in a box in a shed but... The primary angle is 25 and the cutting edge is 32.5, according to a Richard Keil gauge.

the end of the handle is three leather pads. If anyone has any of this pattern they want to get rid of please PM me as I would like a 1/8 and a 1/2. I could be persuaded to swap for more rugged versions

Have a bit of a rootle on the dreaded 'bay. Socket chisels come up quite frequently, and whilst I've never seen one as small as 1/8" (just because I haven't seen one doesn't mean they don't exist, of course!), the 1/2" size is quite a regular offering. Prices for the vintage ones are not too bad either - with postage, a tenner should cover it, and you may get change from that. They seem to be common in the 1/4" to 3/4" range, and occasionally crop up larger than that. I did see a 1 1/2" once (went for silly money), but unless you're rebuilding wooden ships or cathedral rooves you'd be unlikely to find a use for it - no doubt a collector snaffled it.

I succumbed to a few (a selection between 3/16" and 5/8"), not yet in service. All are laminated like Eric's, most seem long-lived and very well used. There's a bit of pitting on a couple that might make return to service a bit of a challenge. The handles vary a lot; a couple turned, a couple made by spokeshave judging from the marks. Handle lengths vary between about 3" and 9", not including the socket taper. One has a short length of thick-walled steel tube fitted like a hoop to the mallet end. One is wrapped in insulation tape - someone couldn't be bothered to replace a split handle!

 

[AndyT]

Well, if it's show and tell time for socketed mortice chisels, here's one I bought from the very same place, before I really realised that socket chisels existed and were a bit different; I just wanted one 1/4" wide:

The junction between hard steel and tough wrought iron is easy to see:

I'm not sure if the handle is boxwood or beech:

There's no maker's name so it's hard to date, but I like its balance; it should be good for another century or so.

 

[Peter T]

....t without guidance where do we start? 20°? 25°?

30º. Try not to forget that.

If in doubt just stick to the time honoured rule of grind at 25 and hone at 30. This has been repeated by just about every woodwork book and woodwork teacher probably for thousands of years and is good practical advice for the beginner.

Poor advice again, IMHO. 25 degrees is fine for most chisels but mortice chisels are better with the primary bevel at 20 degrees.

Makes it much easier to drive the chisel into the wood!

 

[Jacob]

....t without guidance where do we start? 20°? 25°?

30º. Try not to forget that.

If in doubt just stick to the time honoured rule of grind at 25 and hone at 30. This has been repeated by just about every woodwork book and woodwork teacher probably for thousands of years and is good practical advice for the beginner.

Poor advice again, IMHO. 25 degrees is fine for most chisels but mortice chisels are better with the primary bevel at 20 degrees.

Makes it much easier to drive the chisel into the wood!

Wrong.
25/20 OK if you only ever poke gently at things (fine paring etc) but if you did any hard work you'd soon have problems!

 

[Peter T]

Wrong.
25/20 OK if you only ever poke gently at things (fine paring etc) but if you did any hard work you'd soon have problems![/quote]

Why don't you read peoples posts before rushing into print?

OK, let's try again -

Mortice chisel -

Primary bevel - 20 degrees, making it easy to drive into the wood.
Secondary bevel - 35 degrees, to prevent the edge crumbling.

All clear now??

 

[Jacob]

Mortice chisel - 30º edge for most things (I suppose someone might need steeper) and rounded bevel. The rounded bevel is nothing to do with sharpening as such, but is for leverage.
A shallower bevel might make it easier to drive in but would also make it harder to pull out, which is also where the rounded bevel helps.

 

[bugbear]

Wrong.
25/20 OK if you only ever poke gently at things (fine paring etc) but if you did any hard work you'd soon have problems!

Why don't you read peoples posts before rushing into print?

http://en.wikipedia.org/wiki/A_Wise_Old_Owl

BugBear

 

[Jacob]

Wrong.
25/20 OK if you only ever poke gently at things (fine paring etc) but if you did any hard work you'd soon have problems!

Why don't you read peoples posts before rushing into print?

http://en.wikipedia.org/wiki/A_Wise_Old_Owl

BugBear

Why do people post at all when they have nothing to say?

 

[Racers]

I don't know why do you Jacob ;-)

Pete

 

[Cheshirechappie]

At the risk of re-igniting controversy, I'm not convinced about 20 degree primary bevels for heavy-duty chisels, even if the secondary bevel is 30 to 35 degrees. Given the amount of punishment, especially levering back and forth, that such chisels are routinely subjected to, I'm inclined to a rather stronger primary bevel, say about 30 degrees. Then, if the secondary bevel is very small (as it will be after a full regrind) there's still enough meat to resist chipping and edge breakage by over-enthusiastic levering. OK, you have to whack it a bit harder - but you're whacking it hard anyway, especially if you're working something like well-seasoned oak.

Generally speaking, 25/30 for bench chisels, 30/35 for heavy duty work, and 20/25 for fine paring. For extra hard or extra easy-working woods, you might ammend these up or down a bit.

 

[xy mosian]

Just how much effort does it take to sharpen a chisel, mortice or otherwise, and alter it if found lacking?
xy

 

[Cheshirechappie]

Just how much effort does it take to sharpen a chisel, mortice or otherwise, and alter it if found lacking?
xy

Well, if you've chipped a big chunk out of it because the edge wasn't strong enough for duty, potentially more than you'd like in the middle of a job....

 

[GazPal]

Just how much effort does it take to sharpen a chisel, mortice or otherwise, and alter it if found lacking?
xy

Next to no effort if using a grinding wheel, but sometimes quite a lot of effort if attempting it all - re major metal removal - via bench stones. It's always easier to sneak up on (Grind down to) a shallower primary angle than find yourself having to re-grind - wasting valuable edge steel - to a steeper angle.

The downside to hollow grinding is the fact you always remove more metal than intended due to the arc ground into the blade. The angle between edge and rear primary bevel transition can be the desired angle, but the resulting under-sweep caused by the grind often reduces/removes too much metal directly behind the edge and leaves you with a weaker edge. Especially if using smaller than 8" diameter vertical grinding wheels and in comparison to flat ground or free handed bevels which retain as much meat behind an edge as physically possible.

I think Leonard Lee rightly mentions something about the above in his book on sharpening.

------------

A 20 degree primary bevel on mortise chisels is a wee bit shallow for my liking, but I do tend to grind in at between 25 & 30 degrees with a secondary bevel between 30 & 35 degrees depending on timber being worked. Chisel and mallet choice, plus good technique and setting out tend to take care of the rest. :wink:

In terms of force used when mortising I tend to err on the side of using a well hefted mallet to drive chisels rather than opt the brute force route, as this simple option lends itself to enhancing the degree of control one has with each blow and greatly reduces user fatigue. Especially if one has a decent number of mortise to chop during a shift/session. It's also much safer and reduces the number of band aids needed during the working year.