I’m pretty new to woodworking, and previously most of my joinery was cut using power tools. But, for various philosophical reasons, I’ve decided that the cherry table I’m building for my parents will have hand chopped/cut mortises and tenons. Having treated myself to a cabinetmaker’s mortise chisel from the Japan Woodworker (man I love that thing, I mean, aesthetically it’s just a beautiful chisel, at least to my eyes) I set about chopping the mortises when, in a real “how could I be that stupid?” move tried to lever out waste from too deep, heard a crack, and with a sinking feeling in my stomach knew it wasn’t from the wood. A jagged piece 0.5-0.75mm long was broken off the tip, which to me seems like a fairly substantial piece.
So my questions now is, will I be able to fix this? I’m not so sure how the laminated steel is layered: is it straight back through to the handle?. I’m thinking that I can maybe grind a millimeter or so (which seems like a hell of a lot of steel) off the entire body until I can get a straight bevel again, then hopefully lap the hollow face back to flatness behind the cutting edge. Has anybody else ever had to do this? Will it work? Jesus I hope so. Thanks,
Jason
Replies
Yep, just grind it back without getting it too hot, and resestablish both the bevel angle you want and the flat directly behind the edge--and don't lever out the waste <g>.
It could have been worse.
Take care, Mike
I take a slightly different line to Mike and expect mortise chisels to be able to lever out waste-- although I suspect he was in part joking as he attached a smilie deal to his response.
Mortice chisels are intended to dish out and receive abuse. Frankly, if they can't handle abuse, it's my opinion that they're about as much use as a chocolate fireguard or an ashtray on a motorbike.
Japanese chisels do seem to have a reputation for brittleness. To beef the thing up, do as Mike suggested and grind out the broken edge and resharpen. However, if the original grinding angle was about 25° you could also try setting the grinding angle to about 30° which would beef up the amount of metal behind the cutting edge. Then, to hone the tip on the sharpening stone, raise the angle a degree or so to about 31°or 32°. Slainte.
Richard Jones Furniture
Richard
I agree with your opinion that a mortice chisel should be designed to take abuse. I would also advocate regrinding, however my recommendation is a 30 degree primary (which is standard for Japanese bevels) and add a 5 degree secondary/microbevel. That will beef up the tip.
Regards from Perth
Derek
Hah--Richard--that's why I have a couple good ol' English oval bolstered mortice chisels, so I can bash 'em and pry...
Well, ok, I also have a few Sorby sash mortice chisels. On those, it is the handles which require a little care and concern. But as I built mostly dimunitive display cabinets, and moderately-sized drinks cabinets, they work well.
From what I have read and discussed with those who prefer Japanese mortice chisels, prying is not a good thing.
Take care, Mike
"From what I have read and discussed with those who prefer Japanese mortice chisels, prying is not a good thing."
For me Mike, if a mortice chisel can't have seven bells knocked out of it, and can't be used to pry out the waste created I wouldn't give it the time of day. Mortising by hand to me has never been a delicate, pinkie pointing, tea-sipping type job.
If Japanese mortise chisels can't handle that kind of abuse I do rather wonder what they are designed to chop? Slainte.Richard Jones Furniture
Hey Guys,This is very interesting discussion for me as I'm at the point of deciding whether to buy a set of Japanese mortising chisels, or the Lie Nielsen set. I have a set of Japanese bench chisels that I use carefully, and a set of old Marples that I beat on. Both are great, but I don't really want two sets of mortisers.Tom
Tom
I've heard great things about the Ray Iles Oval Bolstered Mortice Chisels (available from Tools for Working Wood). If you don't want to spend as much, unhandled vintage versions are quite cheap (e.g. on eBay). Re-handle them yourself, as I have done.
View Image
I do have a few Japanese mortice chisels, but I now find them too short.
Regards from Perth
Derek
Edit: Hi Mike - our messages posted together
Edited 8/22/2006 12:05 pm ET by derekcohen
Hey Derek!
My neighbor has some Japanese mortise chisels I would consider top-notch--but he made them. Not that it will do the thread any good, but he does know of a few brands/makers that he says are very good for morticing and so I'll ask him.
Adam posted on WoodCentral in the last week or so--or was it here?--concerning method of work. In that iirc he doesn't leverage out chips regardless.
I was out in the shop since my last post and thinking about this. I don't think I leverage out much either. I tend to work, like you, in fairly hard woods and leveraging isn't much an option anyway. I tend to work from the center towards both ends, the center getting progressively deeper until it reaches full depth about the time I am defining the extents of the mortice.
Hmm. I'm going to have to pay closer attention about how I make mortices next time as to whether I leverage or not.
Take care, Mike
***edit to add***I just love the handles on your mortice chisels, Derek. Each time I have seen that picture it makes me want to get some more unhandled chisels! Take care, Mike
Edited 8/22/2006 1:12 pm by mwenz
I would quite happily, and have, honed japanese mortice chisels at 40 degrees, for medium hardwoodsand would consider 45 if working exceptionally dense timbers.
My method involves a small bevel at the tip, a grind of 30 degrees might be enough.
Not prepared to follow the single polished bevel which would theoretically give the strongest edge, as it seems slower to re sharpen.
David Charlesworth
Thanks, DC.
I should have actually mentioned mortice chisel bevel shape as well. I don't leave a flat bevel--not conducive to levering <g>.
I do think a secondary [with a slightly rounded transition] does do more than simply strengthen the tip. I think it helps both deepen the whacks as well as thrust the chisel forward slightly as the mortice is deepened and there is an open area in front of it. Which in turn keeps the bevel from riding [and merely pushing forward] as the mortice is deepened. It's an efficiency of the whacking thing.
Well, that's my story and I'm sticking to it...
PS, do you cover chisels, chisel types, bevel shapes etc. in any of the books? I'm teaching another hand tool class in a month and thought I would make up a little suggested reading list. Kind of hard to keep recommending Hayward...
Take care, Mike
Mike,
Yes, there 10 pages on Japanese chisels in my first book, (can't guarantee to have covered every aspect of every chisel type!) Also something about uses in the dovetailing articles.
Book 3, when it arrives will have at least three more articles.
Best wishes,
David Charlesworth
Oh the better ones can take plenty of abuse. But the laminated portion is very hard, and therefore more brittle. From what I understand, it is the less expensive ones which are more affected by both chipping and breakage.
I prefer Western chisels. With those, it seems the trade-off with the less expensive new ones is rolling edges from being too soft.
The Ray Iles, for new ones, seem pretty darn tough and cost effective. If I needed new, I might go for them. If I was feeling wealthy at my greatest moment of weakness--actually plunking down the dollars--it would be Barrs. And if money was tight, it would be the Two Cherries. Just a couple sizes is all that is needed for my work.
But there are a lot of good vintage ones, especially in the land where you live. You know, where Sheffield braces abound, infills under every rock, and where oval bolstered mortice chisels are ground for tooth picks <g>...Ok, just teasing. But the OBC do appear from there quite often on the Bay. And often for decent prices.
Take care, Mike
You know, even though I work in metric I get it screwed up. The piece in question is more like 0.75 cm (0.75mm would be more like a tiny nick). But thanks, I'm glad to hear that regrinding is possible, and I'll put a larger angle on the bevel to try to prevent this sort of thing in the future.
Jason
commiserations Jason...
I won't try to add (or complicate) the honing advise you've had to date.. merely offer a suggestion to avoid a repeat breakage... there's no loss of face in drilling out some of the waste prior to using the chisel. The voids thus created provide an escape route for the chisel to lever waste into at a far lower pressure.
it's a lesson well learned if it prevents a reoccurrence..
Mike Wallace
Stay safe....Have fun
This forum post is now archived. Commenting has been disabled