Skew chisels for dovetails

[Matt Edwards]

G'evenin all,

I've been practicing diligently on my hand cut dovetails. As my skills are improving I'm finding that I really like the look of the narrow pins. I was looking at buying some dovetail chisels to aid in cleaning out the small gap between the tails, they seem to be a little cashy. I'm now planning on spending some quality time at the grinder to make one or two from some duplicates I have laying around. This got me thinking about skews, is anyone using skewed chisels for cleaning dovetails? Any thoughts on the subject, or recommendations?



Thanks!
Matt

[Joel Moskowitz]

skew chisels are the traditional way to go. fast easy and while some people like "dovetail" chisels (myself included) they didn't exist 40 years ago and the great pre-industrial furniture was all done with chisels that were not even beveled.

So skews are the way to go.

you need a pair - left and right. NArrower is better. Fishtail skews are better than straight skews.

If you have a pair of chisels that you aren't using that's the way to do it. They don't even have to be that good a chisel as they aren't used very often and if they are too hard you will snap off the tip anyway.

So grind away.

[Chris Friesen]

For dovetails you want a not-too-long chisel that isn't top-heavy and which has side bevels to give clearance. The old Stanley 750 shape is fine. With something like a Marples you'd want to grind the side bevels and maybe chop off an inch of the handle.

Skews and fishtails can come in handy when cleaning out the sockets for half-blind dovetails since you can't approach it from both sides--but even without them you can do an adequate job just using a narrow chisel.

[Joe Meazle]

I have been using an AI carving fishtail skew. I was given an AI carving set of 6 by my brother several years ago. I am not a carver but it was one of the few WW gifts I have been given that didn't come from a list that I made for family. So I really admire the effort on his part. It is one of the few carving chisels that sees any use in my shop.

I have my eye on that new AI dovetail set. It would not be required of DT's IMHO but it looks like some pretty sweet bench candy. And is pretty reasonable pricewise compaired to some of the specialized DT options out there. Joel didn't even metion it. In fact he even encourged shop made alteratives. In a era that is filled with shameless self promotion I appricate that very much. I think he is one of the only folks selling it. Gald they are out of stock right now my natural gas bill has been outrageous.

Joe

[Tom Henderson2]

If you have a pair of chisels that you aren't using that's the way to do it. They don't even have to be that good a chisel as they aren't used very often and if they are too hard you will snap off the tip anyway.

So grind away.

What is a typical skew angle?

Thanks in advance...

-Tom H.
Ventura, CA

[Jim Koepke]

My skew chisels were made out of some 1/2 inch flat sided Witherby's. They are a bit big for small dovetails.

For dovetails, my most handy chisel for small pins and half blinds is my 1/8 inch bevel edge chisel.

jim

[John Keeton]

I am a real beginner at handcut dovetails, but sometimes I think that may be an advantage for questions like this as I have not settled into anything that has become "my way" of doing it.

I have skew chisels that I owned before trying handcuts. But, they really don't seem to help me near as much as a couple of fishtail chisels I made from some rough chisels I had laying around. Those really come in handy.

And, like Jim, I use the 1/8" bevel edge chisel a lot. There have been various threads on chisel selection, but I can highly recommend the Blue Spruce chisels for dovetails. Very thin side edges with concave side bevels, beautiful workmanship, light, comfortable, and boy do they handle well.

Others will have their favorites, as well.

[Joel Moskowitz]

What is a typical skew angle?

Thanks in advance...

-Tom H.
Ventura, CA

on good chisels - ones that are properly hardened and there is a risk of snapping 15 degrees is fine.

on a shew fishtail - since the fishtail gives you wiggle room 15 is also fine.

on cheaper/ softer chisels also ones that are wider I think 30 degrees is more useful. but anything in between will work and certainly you can start shallower and work your way up.

[John Keeton]

Joel, I think he was asking about the skew angle as opposed to the sharpness bevel. I have seen skews at 20 - 25 degrees. I believe Lie Nielsen are 20 degrees, sharpened to a 30 degree bevel.

I sharpened my fishtails at about 15 - 20 degrees and they work fine. I use them only for cleaning up the corners and paring, so little chance of breakage.

[Matt Edwards]

Thanks for all the replies and great advice! It will be an interesting project I'm sure. The plan right now is to make an assortment, skew, fishtail and dovetail and put them to use. Which ever becomes the go to will be what I buy down the road.

Here's another question. Would an old file, annealed, shaped and re hardened be a decent beginning of a fishtail chisel?

Thanks again!!
Matt

[Joel Moskowitz]

matt,
sure,
but what you want is a pair of fishtail skews, not plain fishtails, about 1/4" wide or narrower and once you make them there will be no point in buying them ever.

[Derek Cohen]

I'm a little confused here. All this talk of skews and fishtail chisels - they are useful chisels but I rarely use skews for anything but half-blind dovetails, and I never use fishtails for anything but half-blind dovetails.

So when Matt writes, As my skills are improving I'm finding that I really like the look of the narrow pins. I was looking at buying some dovetail chisels to aid in cleaning out the small gap between the tails.. what is he refering to?

Both skews and fishtails are easy to make.

I made this fishtail some years ago. The angle is ground at 1:8.

http://i13.photobucket.com/albums/a262/Derek50/Chisels/Dovetailchisel1.jpg

Skews are even easier. I prefer a 20 degree skew. The angle of the bevel depends on the steel - LN and Blue Spruce use a 30 degree bevel as they use A2. If you have HCS or O1, then go to 25 degrees.

Here are a couple I ground ...

http://i13.photobucket.com/albums/a262/Derek50/Chisels/Skewchisels.jpg

In my opinion, the best tool for cleaning out the side angles is a chisel with a sharp side arris. You can grind these youself. The three sizes I use most for narrow pins are 1/8", 3/16" and 1/4"..... you are not going to get a skew chisel in there!

Regards from Perth

Derek

[David Keller NC]

"What is a typical skew angle?"

Tom - A bit of an expansion on Joel's recommendation based on personal experience and talking with David Jeske (Blue Spruce Toolworks). I had a set of David's wonderful skew chisels that were nearly the first he produced. They were ground at a 45 degree angle. As Joel notes, that makes the tips pretty fragile, and I managed to snap off a 1/32nd of the end of both of these.

In talking with David, he recommended grinding them to a 25 degree angle, which I did and have not had further problems with the tips keeping their edge when working in moderately hard woods like mahogany. I would note, however, that I did snap off the very tips of some older chisels that I ground to the same 25 degree angle while working in maple; I've re-ground these to 15 degrees, and while the edge is quite sturdy, it also limits the usefullness of the chisel in certain dovetail geometries (typically, 14 degree tails).

[Derek Cohen]

I have a set of Blue Spruce skews. When I ordered them, about two years ago, from memory David was only producing them in the 45 degree angle as noted. I had mine made up at 20 degrees. After ordering them, LN began making them as well, and they, too, chose 20 degrees.

Regards from Perth

Derek

[Matt Edwards]

So when Matt writes, As my skills are improving I'm finding that I really like the look of the narrow pins. I was looking at buying some dovetail chisels to aid in cleaning out the small gap between the tails.. what is he referring to?



Hi Derek,

What I'm referring to is removing the waste and cleaning out between the tails when the pin is narrow like, say 5/16" at the wide part and barely 1/8" at the other end. I'm guessing that a standard dovetail chisel is what is need for the through DT's. Something a little thinner and alot more tapered from the back to give more clearance from the sides of the tails. I realize (hope :) ) that with more practice the need for this type of clean up will decrease with better technique and skill. Of course the next step in the learning curve will be half blinds, which will most likely bring on the need for the skewd's.

One thing is for certain, (in my case) with dovetails, the more skill with the saw = less work with the chisels.

Thanks!
Matt

[Paul Saffold]

What do you use to grind the skew/fishtail chisels? Do you need to anneal first?

Thanks, Paul

[Jim Koepke]

What do you use to grind the skew/fishtail chisels? Do you need to anneal first?

Thanks, Paul

I have used my Veritas MK II power sharpening system. The blade holders come with a way to mount skewed blades or to make skewed blades from straight ones.

It takes a while to cut them, but no need to do any heat treating if you go slow and do not burn the chisels. In other words, I followed the directions that come with the equipment.

jim

[Joel Moskowitz]

What do you use to grind the skew/fishtail chisels? Do you need to anneal first?

Thanks, Paul

See my article in june 08 FWW for details on grinding.

1 - with the chisel rest square to the wheel grind whatever skew angle you want. - just lay it out with a pencil and grind to the line.
2 - then with the rest still sqaure do any fishtailing on the side you want.

3 set the rest to 25 degrees and grind the bevel angle.till the thinkness in the front goes away. be carefull it is really thin at the tip.

4 - hone by hand to finish.

[Paul Saffold]

Thanks Jim.
I have a bench grinder and a belt sander and was hoping that I might be able to make a fishtail with them. When the yard sales start up this spring I'll pick up a couple of small chisels and see what I can do to them.

Paul

[Paul Saffold]

Thanks Joel. I think our messages crossed. I'll try your method.

Paul

[Derek Cohen]

One could grind a skew (from a straight edge) three ways:

1. A wet grinder, such as a Tormek - but this would be very slow. Not my idea of fun.

2. A belt sander with an 80 grit belt. A good method as the belts run fairly cool. But nevertheless you must use a light touch and dunk them in water.

3. Only use a 3X Norton (if you have the choice) or a white wheel - NEVER a grey wheel, which creates far too much heat as they are not very friable. And always a low grit, such as a 46. The 3X I got from Joel (at TFWW) is the coolest running grinder wheel I have used (I have a 8" half-speed machine).

Regards from Perth

Derek

[Louis Reed]

I use a set of needle files to clean out the dovetails, works great ! You can get a cheap set at HF.

Louis

[Mike Henderson]

Skews for dovetail work aren't used that much - unless you do an awful lot of dovetails. Pick up two 1/4" chisels (regular chisels) from eBay or new Irwins and just grind them to a skew the way described above. You should be able to get away for about $15 each.

Mike

[george wilson]

I have never used skew chisels for cutting dovetails. I can't really see that they are necessary. A comment was made that early dovetails were cut without beveled chisels. They used to just grind away a bevel on each side of the chisel so the square edges would go into a dovetail more easily. The grind was on the sides of the chisel,and angled outwards as they got away from the edge. The edge itself was left square. These "bevels" were usually only about 1/2",0r 5/8" long,and tapered away to nothing,leaving the square edge the rest of the length. I always thought they looked bad,but,they got the job done.

There was a beveled edge chisel found from a known 16th.C. site at Novaya Zemblya(sp?),where some sailors were marooned for some time . Barents,the explorer,died there IIRC. they built a house out of wood from the ship. It looks a lot like a short Swedish type chisel (Shark brand) of today. Actually,the blade itself also tapered a little in width towards the tang. Apparently beveled chisels were not common then.