Chisel inch or mm Sizes

[Kim Howarter]

Is there any problem or issue with having chisels that are sized in mm instead of inches?

I bought a Woodriver set on sale at Woodcraft that is marked in inches and specifically asked if it was inches and was told that it was. I got it home and measured it with a caliper and found that it doesn't measure to match inches or mm sizes.


Thanks,
Kim

[David Weaver]

No big deal. Just size the chisel to your work.

[Andrew Pitonyak]

I think Dave meant to say size your work to the chisel ;)

So, if you want to cut a 1/4" mortise, well, size the mortise to be the chisel that is closest in size to 1/4".

[David Weaver]

I didn't choose good words for that at all.

Just pick the chisel that best fits what you're doing and use it.

Is the set you got the bubinga handled 8 piece set that has "CHINA" stamped on the back of the blades?

I got those last year as part of an argument, and figured I'd repurpose them for something. They're actually not too bad, and they weren't that bad to prep.

But I have zero practical use for them.

[Sean Hughto]

Yes, there can be a problem depending upon what you are doing or how you work. First thing that comes to mind is that there are instances when you want a chisel that corresponds to the width of another tool - say a blade on a plow plane that you've used to cut a groove.

[Jon van der Linden]

Yes, there can be a problem depending upon what you are doing or how you work. First thing that comes to mind is that there are instances when you want a chisel that corresponds to the width of another tool - say a blade on a plow plane that you've used to cut a groove.

This is absolutely correct. However, knowing that they probably won't match up, why would you design your joints so that they have to match up? Worst case is you use a smaller tool and have to use a little care getting a mortise to match a groove or something like that. You might find it annoying, but this is the way it's been done since the dawn of time... unless you go into large machines and industrial tooling where you can easily match these things up with extreme accuracy.

[Sean Hughto]

However, knowing that they probably won't match up, why would you design your joints so that they have to match up?

Is this a trick question?


You might find it annoying ...

Yeah, it's that annoyance I was suggesting could be avoided if one had standard imperial sizes (or metric) across your whole kit. My 1/4" chisel will indeed match my 1/4" plow blades or 1/4" dado plane blades, or my 1/4 electric router bits, for that matter.

All that said, it's not the biggest deal in the world, but given a choice (and if your methods of work would make it a convenience) have your tools match sizes.

[Jon van der Linden]

Is this a trick question?

Well, yes. Why do people insist on following someone else's method of construction without thinking? Probably the same reason that most people don't design anything but only make copies of other's work. My point is there are many ways to design the construction aspect of things and you should design the construction around what you can do and the tools you have... unless you're looking for an excuse to buy something, an activity that I wholeheartedly support!

When it comes to matching things up I still like using a Martin shaper and Maka mortiser more than trying to line up some stuff with a router, it's just a LOT more accurate and repeatable. In the end it still doesn't accomplish more than you can by hand given thought and attention.

[Tony Shea]

When it comes to matching things up I still like using a Martin shaper and Maka mortiser more than trying to line up some stuff with a router


Boy, I couldn't agree more with that statement. I was recently setting my router up for some, I thought to be, quick mortises for a set of Krenov style saw horses and spent forever setting my router up accuratly for the few mortises I had to make. Not only did it seem to take forever but I also went through a bunch of scrap testing the location of the mortise out. Even after all that setup I still ended up with a couple that were not parallel with the edge of the board therefore needed to make my tenon larger than neccessary to accomodate for weird mortise. My point is that I could've just pounded these out with my 3/8" LN mortise chisel in probably less time than the other process took.

To answer the original question I agree with Sean in that it can and does pose difficulties when chisel widths don't match other tool blade widths. I have experienced this first hand as I own a couple metric chisels and have run into issues with their sizes. The other place I sometimes have issues with the metric size is when centering a mortise on the stock. I can usually get my tools and marks set up real close with some measurements with minor tweaking. Throw the metric chisel in the mix and I become useless as I have no means to measure it. This really isn't a real issue but just a minor inconvienance I run into once in a great while. Very easy to over come it as long as you understand you're using the metric chisel to begin with. I have a number of metric beveled edge chisels and use them a lot without issue. But there are times.

[Jim Koepke]

I think for many uses, it really doesn't matter.

When my intention is to make a mortise, the gauge is set to the chisel and everything falls into place with that.

For cutting dovetails, my practice is to have the waste a little wider than the chisels that will be used.

Cutting dados is a little bit different. Often there will be a need to do a little clean up after using a plough plane or to use a router plane after cutting with a chisel. That is where one will have to use a bit more attention to keep from getting messed up by a mismatch of sizes.

The other problem comes from standard wood sizes. Some plywood is coming in metric sizes, but I do not use plywood.

I have a few chisels that are marked as both. The problem is, 18 mm does not equal 3/4 inch no matter how many things they stamp saying that it is.

jim

[David Weaver]

Decimal inches is the way to go if you're going to be mixing standard and metric.

I wish everything we had was already in metric, anyway, it just makes life a lot easier when you're measuring things and halving them, etc.

Decimal inches works just as well, but fractional - yuck..."what's 1/2 of 27 1/64th" (yes, I can do it in my head 13 65/128, or pretty darned close to 13 1/2 depending on whether it matters, but who wants to do that while you're working wood). So much nicer if everything is short to go in mms, and say stuff like "what's half of 686". No mistakenly reading a 32nd instead of a 64th or 3/16ths instead of 5/16ths, or whatever else.

[Sean Hughto]

My point is there are many ways to design the construction aspect of things and you should design the construction around what you can do and the tools you have... unless you're looking for an excuse to buy something, an activity that I wholeheartedly support!


"buying something" is the OP's point - he stated that he bought some Woodcraft chisels that were sold as imperial and they really were not and asked if it mattered. Presumably the implication was that if it mattered he might return them to get the thing (imperial chisels) that would allow him to design work sequences and practices that took advantage of same sizing.

[Frank Drew]

My first chisels, when I was learning carpentry, were a cheap-ass set from Sears, Imperial sized. When I began to take woodworking seriously I got some other, better, chisels over the years in both inch and mm sizes.

My last, and favorite, set is Japanese and is sized to their carpenter's measuring system.

Maybe by not having all my tools in one system of measurement meant I ran into a problem once or twice, but if so the inconvenience was so minor that I've forgotten all about it. The sizing system wouldn't stop me from buying an edge tool I liked.

[Jim Koepke]

"buying something" is the OP's point - he stated that he bought some Woodcraft chisels that were sold as imperial and they really were not and asked if it mattered. Presumably the implication was that if it mattered he might return them to get the thing (imperial chisels) that would allow him to design work sequences and practices that took advantage of same sizing.

Having just gotten home and being a little tired got me to read all the posts and lose focus on the original poster's question.

If I was a bit more focused, I would likely have responded:

Kim,

Welcome to the Creek.

If you can and that is your desire, I would return the chisels for a refund or credit toward a different set.

The life of a woodworking can be easier with tools all sized to the same standard.

jim

[Jonathan McCullough]

It's been said here before and I'll say it again: if you can't do what you need with either a 6mm chisel or a 1/4 inch chisel, (or a 12mm vs 1/2 inch and so forth), you don't know how to use a chisel. And that's fine. No one is born knowing how to use a chisel. Is your mortise bigger than your chisel? Scoot the chisel over a bit. Is the chisel too big? Use the next one smaller. So many aspects of joinery are going to be test-fitted anyway that creeping up on what you need with either metric or imperial is a moot point if you're going to sand or pare or shoulder-plane that last bit away anyhow. I just can't imagine an instance where it would matter. It's woodworking, not engineering. Evaluating the chisels based on the steel would be appropriate. If they came to someone already burnt, or chipped like glass after several sharpenings, or broke with what you consider to be an unacceptable amount of light mallet-pounding, or bent over with finger pressure like a common nail, anyone would be well within their rights to seek a replacement or your money back. But you'll probably find slight variations in sizing between, and even within brands.

[Wilbur Pan]

But you'll probably find slight variations in sizing between, and even within brands.

Completely true.


Yeah, it's that annoyance I was suggesting could be avoided if one had standard imperial sizes (or metric) across your whole kit. My 1/4" chisel will indeed match my 1/4" plow blades or 1/4" dado plane blades, or my 1/4 electric router bits, for that matter.

All that said, it's not the biggest deal in the world, but given a choice (and if your methods of work would make it a convenience) have your tools match sizes.

If it's that critical of an issue, it's a trivial task to go to your grinding method of choice and change the width of your chisel to match the width of the other tools.

[Kim Howarter]

Everyone,
Thanks for the input. I am going to give this some more thought before I decide, but being told that the chisels are inch when they are neither is the part that upsets me the most.

Here are the measured sizes of the chisels:

.235" = 5.969 mm
.402" = 10.211 mm
.475" = 12.065 mm
.640" = 16.256 mm
.715" = 18.1161 mm
.993" = 25.222 mm
1.269" = 32.233 mm
1.503" = 38.176 mm

I have a couple of other inch chisels that measure within .001" of the stated size. These sizes just don't make sense to me.

[Jim Koepke]

These sizes just don't make sense to me.


They might if one were to take into account the tolerances allowed to lower the cost of making an item.

They appear to have been made to metric sizes for the U.S. market with about 0.5 mm room for error.

The most important part would be if they can hold an edge.

I am not sure of the return policy where you bought them.

jim

[Jonathan McCullough]

Okay, look. What you have there is a good variety of sizes in a value-priced set of what appear from most reports to be serviceable chisels. The medium they are intended for, Wood, is not something permanent in size. It changes with temperature, humidity, and probably age as some parts of the wood oxidize over the years. Your biggest chisel is three one thousandths, or, what, five hairs' difference? from 1 1/2 inches. The question is, can you do good work with that chisel? Well. . . . a poor workman blames his tools, and not a single master joiner had a micrometer until the last century, or, probably, chisels measured to within an angstrom of certainty. Put away the feeler gauges and micrometers. Open up the books. Sharpen up the chisels, and get a piece of scrap pine. Chop it. Pare it. Try to carve your kid's name (or whatever) in it. It's a pleasure and you'll get a feel for the wood. When you have a task that calls for a chisel, take one down and try it. Does it feel too big or big or small for the task? Try the next size up or down. You really won't miss the seven thousandths from your one inch chisel. If you need to take an extra seven thousandths off a different dimension because your chisel is off (and your chisel will always be off, regardless of what you're doing or which chisels you have) just turn the piece around and plane or chisel or router the offending seven thou's away. It's not CNC machining.

[Kim Howarter]

I suppose that the tolerance issue may be the reason but that doesn't mean that I have to like it. Reminds me of working for a pressure washer company that used a 20% tolerance.

I can return the chisels with no problem.

[lowell holmes]

It matters to me. I pretty much use only imperial sizes. I file my plow plane irons to imperial sizes. My router planes are imperial sizes.

I do have a 1/2" mortise chisel that is metric, but I'm thinking about grinding it to imperial.

[Stuart Tierney]

Hi Karen,

Well, I have quite a few chisels and have cut quite a lot with them, including but not restricted to joinery.

I cannot in all honesty tell you what width any single chisel I own is, other than the nominal dimension. I may have measured them at some point, but 90% of them are an absolute mystery to me with regard to their sizing.

I can and have worked to extremely tight dimensions, and used chisels as part of that, and it's never been an issue. I have done work where I did not measure a single thing, and of course, the absolute size of any tool was not important.


To be completely honest, anyone who gets really wound up about a chisel that is 'not accurately sized' makes me wonder what on earth they are doing that requires such accuracy from a tool that, by design, requires no such tolerances.

More important is whether the steel is decent, the tools are finished well enough and that they are as functional as can be expected. If so, then they are fine. If however the width is so critical, take them back and ask for a refund and do it before you try them out.

Me, I'd sharpen them up and see how they go. If good, great! If not, then they'd be going back pretty quickly...


(And I say that as someone who is waiting for the doorbell to ring, because when it does, there will be a few $K worth of chisels on the other side of the door. I'm not going to measure any of them in any way, shape or form. Well, maybe the specially made ones will get a cursory date with a protractor just for the heck of it. That's how unimportant it really is, and the chisels are not even mine, they are going to be scooting all over the globe and I bet that none of their new owners are going to give more than a few milliseconds of thought as to whether they are 'on size' or not.)

I really hope that helps you out, and I would be the very last person to say you would be foolish for taking them back. If you have gone to the trouble to measure them, and been disappointed with what you have found, then that's enough excuse. ;)

[Dave Anderson NH]

The bottom line Kim is that everyone here is correct even though they disagree. It, like many things in woodworking, is both a matter of opinion and is based on how an individual works.

I personally work with western tools and the imperial measurement system. My choice was based on inheriting a large number of family tools all US or Uk made in the 19th and 20th centuries or purchased by me as additions and fill ins. I don't think that anyone can argue against the fact that you can work more efficiently if all of your tools match, but conversely, there is always a way to adapt.

A note to folks here about talking tolerances, micrometers, calipers, etc. While most of us Neanderthals do "one off" work and rely primarily on test fitting joinery, if you did use precision measuring devices you might get a surprise. As an example, the difference between a properly fitting mortise and tenon joint and one that is either too tight or too loose is less than .015", roughly 1/64" in either direction. Some folks even claim the difference is as little as .005" We are doing precision work, we just don't always measure it with measuring tools.

[Dave Ring]

Of course, if you just don't like these chisels you have a perfectly reasonable excuse for returning them.

[Frank Drew]

I do have a 1/2" mortise chisel that is metric...

Now that's a paradox :D.

[Kim Howarter]

Dave, I agree, we all have our opinions. It is up to me to decide how I want to work. Having worked for 30 years in Quality Assurance I have worked mostly in inches, and when measurements were metric, they were checked in inch and converted to mm.

Since I have 4 other chisels (2 @ 3/4" and 2 @ 3/4") I thought the inch versions would be a better choice.

I do my woodwork with a caliper to measure how well my cuts fit, especially when doing a dado, router bit depth, etc. I have to think about it if someone says 16 mm to determine that it is very close to 5/8" at .630.

I will see how these chisels feel in my hands and if I like it I will probably use them.

[David Weaver]

I think you'll find that you can do work fine with them.

If it makes you feel any better, the hand forged japanese chisels vary from their stated size, at least that's what they say when you buy them.

I haven't ever checked mine to see if they match the size they say they are, and the hand forged set that I have has no numerical measurements on it at all, not on the handle or anything.

You just pick up what you want to use and go at it. If the japanese tradition doesn't require perfectly sized chisels, then doing anything other than matching power tool sizes for sport is really not required. There isn't a lack of precision in japanese joinery, for sure.

[Sean Hughto]

This has been an interesting conversation for many reasons, some of which have nothing to do with woodworking. :rolleyes:

There's the "make do" argument: a good woodworker can get 'er done anyway. Well, sure, but the idea of good tools is to avoid making do and instead to achieve optimal results the most effectively and efficiently.

There's the "handwork is both super precise and has no need of measurement nor micrometers" argument. Yes, but those suggesting that on occasion it is nice to have chisels that match the size of your other tools are not arguing that a groove necessarily has to be 1/4 rather than 17/64ths, but instead are simply noting that it is nice when different tools contributing to the effort match (on whatever nominal measurement).

There's the "I've never had need of a match, and therefore, anyone who has is doing something weird or wrong" argument. Versions of this one are common in woodworking threads of all sorts. There are many ways to skin most woodworking cats, and it's very infrequent that one way is the obvious "best" for all woodworkers in all situations. These are merely methods of work and tool choices after all, the "best" that we care about is the result of the use of the tools.

All that said, I certainly concede, as I have a few times in this thread, that chisels sizes are much less likely to be crucial than say combination wrench sizes (how would you like to have to use metric wrenches on imperial nuts and bolts all the time?). Standardization is at the heart of the function of a combination wrench; standardization does not come into play for most chisel work, but it does occasionally, and when t does so, it's nice to have well sized chisels.

An interesting conversation might be some discussion of when in those blue moons that chisel size standardization come in handy. A few that come to mind for me:

When making a frame and panel door, after cutting the grooves in the frame members with my (Stanley 248) plow plane, it's very nice to have a mortising chisel that is the same width as the groove to chop the mortises with - the groove guides the chisel, and making the haunched tenon to both fit the mortise and fill the groove is simplified because you are dealing with only one thickness.

Squaring and excavating the ends of stopped grooves is somewhat more convenient with a chisel that matches the groove or dado width as is paring the bottom of the groove if it need to be deepened.

Chopping a groove on the arch of a tombstone or other curve topped door to match the grooves you've made on the straight members of the frame is somewhat more efficient with chisel that matches the width of the plane's blade.

Note that I didn't say that any of these tasks couldn't have been done with a smaller chisel. All I said was that it was nice to have matches in these circumstances; it cuts down on the extra work of moving the chisel around to get to all the waste.

For what it's worth.

[Jonathan McCullough]

Yes, joinery is a precision affair, but whether you arrive at it with chisels measured in metric or imperial measurements is irrelevant. If you're sticking 1/4 inch chisels in 1/4 inch dadoes, one or the other really isn't 1/4 inch because by definition, an exact tolerance match will not fit. Ever tried to put a 1/8 inch dowel in a 1/8 inch hole? It doesn't fit because you need a tolerance--the dowel has to be probably about .002 inches smaller (or the hole that much bigger) in order to get the dowel in there. The same is true for any material. There are whole books written about tolerances for different materials. How you get something to fit into a 1/4 inch dado is a matter of fitting, of adjustment until something fits. Does your 3/4 inch tennon not fit into your .750-inch mortise? What do you do? Get the 0.751-inch sized chisel from your 1000-piece chisel selection from zero to one inch in one thousandths of an inch steps and redo the mortise? Or do you knock a thou off the mortise with some sandpaper or a shoulder plane or whatever's handy? If your mortise is too big for the tennon, what do you do?You stuff a .003 inch thick plane shaving in there in the knowledge that nobody's going to know for at least forty years, and by then you may well be pushing up daisies. Dudes, you could *bruise* a joint in soft wood by .003 inch just by mangling it with your chisel.

The best thing about metric chisels is that they're often cheaper because people have hang-ups about what size they are. Yes, socket wrenches are different, but we're not talking about socket wrenches. And there again, you're going to have tolerance clearances. Your 1/2 inch socket wrench probably isn't .5000000 inches.

[Sean Hughto]

Ever tried to put a 1/8 inch dowel in a 1/8 inch hole? It doesn't fit because you need a tolerance--the dowel has to be probably about .002 inches smaller (or the hole that much bigger) in order to get the dowel in there. The same is true for any material.

Not so much. Decided to take 5 minutes in the shop to make sure my memory of my experiences was accurate. Photos posted below. It was a perfect push fit. Both parts are hard maple.

Also checked several brands and vintages of chisels from my drawer - LN, Stanley 750, Swan, and Blue Spruce. All matched perfectly and measured the same with my dial calipers.

Just lucky I guess.

[lowell holmes]

It is a Marples registered chisel. The size marked on it (as Marples are marked) states two sizes, 1/2" and 13mm. A mortise chopped with it is a bit loose if I happen to adjust the mortise with my 1/2" LN. It really isn't a major issue, but . . . .

I learned to chop mortises with Marples blue handle bench chisels. So, it really is not a big issue.

When I was making a blind dado with my rosewood plow plane from Japan Woodworker, the iron on the plane was 6mm. That doesn't work well with a 1/4" LN bench chisel. It was an easy fix, filing the iron down to 1/4". The iron in the plane is softer than chisles.

Christopher Schwartz talks about "slaving" your tools, which is matching the tools to the same width.

So, more renown woodworkers than me (who is unknown) worry about it as well.

:)

[Jonathan McCullough]

Okay, this is a bit out in the weeds, but . . . the drill bit is smaller than the dowel plate hole. How do we know? Because it fits inside the hole. "A perfect fit doesn't fit." The dowel fits in the hole in the wood because it wood has plastic properties; the dowel compresses, the wood around the hole expands.

Here's another example. Take a chisel and drive it deep into a piece of wood. If you can't easily get the chisel out, that's an example of a perfect fit. How did it get there? The chisel cut the fibers and moved them away. Why is it a perfect fit? There is no tolerance to get the chisel out; it won't easily move. How do you get the chisel out? move it back and forth until the wood compresses enough to give up enough tolerance to back the chisel out. Could you repeat this experiment with steel? Here's how. One old trick to get closely matched parts to mate is to heat the female part up so that it expands. Put the male in, and let the two cool together.

The point I'm trying to make is that all of your joinery is going to be custom-fit anyway, and in a medium that is elastic. Does any of this really require chisels of exact specifications? I don't think so. Sean gave some pretty good examples of when it would be nice to have a chisel that matches closely. But is it necessary? No. And the thing is, can we think of instances when it's not critical for the chisel to match closely? Yes: Everything else.

The only person I can think of who introduces this sort of precision to his work in a genuinely useful way is Kevin Glen-Drake. He uses feeler gauges to offset mating pieces in dovetails so that the kerf plus a tolerance will allow you (and some experience sawing) to put dovetail joints together right off the saw.

[Mike Henderson]

At one time, I was into buying old American made chisels. Most of them are only approximate to the size advertised - they're either a bit bigger or a bit smaller. And, of course, every now and then I'd get one that was the correct size.

This leads me to the belief that our woodworking ancestors had tools that were not all the same sizes (a half inch chisel was not the same size as a half inch plow plane), yet they worked with them and produced good work.

Quality modern tools are generally the size indicated. For example, a LN chisel is exactly (or within a very small tolerance) the size advertised.

It's all what you want and what you're willing to pay. But you, also, can do excellent work with "approximate" chisels.

Mike

[Joe Mioux]

my favorite chisels are mm,

My 10 mm ((or whatever the closest chisel mm is to 1/2 inch) chisel doesn't care if I am chopping a 1/2 inch (12.7mm) mortise or something larger. ;) It does both admirably.

with that said, I do get bugged a bit converting festool domino slots.... :confused:

[Sean Hughto]

Okay, this is a bit out in the weeds, but . . . the drill bit is smaller than the dowel plate hole.

Wow, that would make it even worse because that very drill bit drilled the "undersized" hole and that very dowel plate amde the "oversized" dowel. But seriously, the tiny amounts of play and the compressability of wood in all these situations pretty much refute your idea that a 1/4 inch chisel won't "fit" in a 1/4" groove. I've done it many times; the chisel will work in the groove just as surely as this dowel slipped into this hole like a piston.



Here's another example. Take a chisel and drive it deep into a piece of wood. If you can't easily get the chisel out, that's an example of a perfect fit.

No, that's an example of the physics of wedges and the compressibility of the fibers of the wood acting to keep the wedge in place. You can get your drill bits out of wood right?

[Jonathan McCullough]

I think we'll have to agree to disagree. I'll refer you to pages 627 - 672 of Machinery's Handbook, 28th edition. You know you're right about the chisel example, it's not a perfect fit, it's a called a force fit. When you're putting a perfectly sized 1/4-inch chisel into a perfectly sized 1/4 inch dado, you are moving the wood over in order to accommodate the chisel. The point is that as woodworkers, we are not operating with such precision as we might suppose, and whether our chisels are .246 or .250 or .254 inches is irrelevant. It's good to have a variety of sizes.

On getting your drill bits out of wood: Do your drill bits not bind in the wood if you stop the bit while it's still in the wood? Mine do. I think a lot of things are happening there. Both the wood and drill bit are heating up and expanding. Some sap in the wood might have some effect. Would a drill bit bind in metal if you drilled slowly enough, and stopped the bit? I'll bet it would: there's zero tolerance. The reason you can drill a hole in something and pull the drill bit out as it's spinning is because the force of the rotation can overcome the newtonian "natural" force of the object pressing against the drill bit. Interesting question.

[Jamie Bacon]

Personally, I'd return them. They are not what you thought you were buying. And I'm in the camp that likes my chisel size to match my plow plane irons, router planes, etc. I guess it would be a little more critical for me if these were mortice chisels, but again, they're not what they were advertised as. Just my opinion on it.

Jamie Bacon

[Jim Koepke]

When I was making a blind dado with my rosewood plow plane from Japan Woodworker, the iron on the plane was 6mm. That doesn't work well with a 1/4" LN bench chisel. It was an easy fix, filing the iron down to 1/4". The iron in the plane is softer than chisles.

I'll consider paying your airfare to come out here and teach me the trick of filing a 6 mm wide piece of iron in to 1/4".

1/4" = 6.35 mm and that is the reason a lot of metric sets in the U.S. have a 6.5 mm wrench.

jim

[Jim Koepke]

Though it is true that one could cut a 3/4 inch dado with a smaller chisel, to me it is much less work to use a chisel that better matches the deminsions of the lumber that is being used.

Yes, we often put things together without measuring. When it comes down to the final fit the closer the sizes of tools come to each other and the material used, the less trimming has to be done to get to the final fit. We may love doing our work, but there is no need to make it more work.

I have a few chisels that are in metric sizes. They are fine chisels. They do not match my imperial size chisels and thus seldom get used unless there is a call for something that is slightly off size.

If I thought I could get a good price for them, I would sell them. Until I have a need for money more than the comfort of not having to box them up and ship them, they will sit among my other chisels waiting to be used or not.

jim

[lowell holmes]

I mispoke. The iron in the plane was probably 6.5 to 7 mm, it was wider than the 1/4" chisel. I don't have calipers that measure in mm. I know that 1/4" = 6.35 mm.

I prefer to have my tools match. No other discussion matters.

I also can tell you that in fabrication drawings, seldom to do you see 6.35mm plate. Plate will be called out as 6mm. Tolerances will allow the actual thickness to vary.

The 13mm chisel I have is greater than 1/2". If I'm not matching a 1/2" dado, it doesn't matter. I really would like for it to match my 1/2" LN bench chisel though.

If your offering me a free vacation, I'll accept though. :)

[Sean Hughto]

Okay. It all brings to mind that Yogi Berra (some say Einstein) quote:

In theory there is no difference between theory and practice. In practice there is.