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jonathan snyder
09-04-2006, 12:22 AM
Hi folks,

I put that bishop dovetail saw to use. I spent some time making practice cuts, I guess I need to do more. I cut my first couple of sets of dovetails this weekend. Here are the pics.

1st pic is my first try
2nd pic, second try
3rd & 4th pics are my 4th set.



46100

46101

46102

46103

I am using a lee vallley dovetail marker and striking knife.
I cut the pins first.

Just out of curiosity who cuts pins first and why? Who cuts tails first and why?

I am having difficulty scribing a clean shoulder line. I suspect it is my marking guage. I'm using an inexpensive guage with a pin. Any suggestions or should I get a guage with a wheel?

Cutting the pins goes pretty well, its the tails that are tough. When I scribe the tails, the knife marks are on the inside of the piece. I then scribe the end grain with the dovetail marker, and try to make my cut folowing those two knife marks. My tails turn out tight on the inside, but loose on the show side (you can see the gaps). I guess I'm not quite getting the angle right.

Any tips or words of wisdom would be appreciated! I have read numerous articles and watched the Tage Frid video.

Thanks
Jonathan

Martin Shupe
09-04-2006, 12:59 AM
I cut tails first, because that is the way Kelly Mehler taught me. He says it is easier that way. I believe him. I am by no means an expert.

As far as marking gauges go, you can get an inexpensive one with a wheel from Lee Valley. A better one is sold by LN, made by Glen Drake. I have used both, and like the Glen Drake version better. Just my opinion. Wheels are easier than pins, in my opinion.

Good dovetails take practice. Layout is crucial, as is cutting to the marked line. Using a chisel correctly to remove the waste is also important. You will get better the more you do them.

Try cutting some tails first, and see if you think it is easier, then decide which way you like best, and don't worry about what anybody else does.

Brett Baldwin
09-04-2006, 2:01 AM
I am also trying dovetails for the first time and so far I am finding that it is easier to fine tune with the chisels than try to hit the lines with the saw the first itme around. Maybe try to leave more on the waste side and pare down to the final fit more gradually. If you pay attention to where youare having to pare away most, you'll know where to saw tighter to the next time. Before long they'll be so tight you'll have to make room for the glue.;)

Alan DuBoff
09-04-2006, 5:01 AM
I put that bishop dovetail saw to use. I spent some time making practice cuts, I guess I need to do more. I cut my first couple of sets of dovetails this weekend. Here are the pics.You always need to do more, but you're well on your way to a nice skill, the ones you've done are very good for your first ones, IMO. I have the first dovetail I cut laying around the shop somewhere. I dated it and saved it.

I am using a lee vallley dovetail marker and striking knife.
I cut the pins first.

Just out of curiosity who cuts pins first and why? Who cuts tails first and why?I find they both compliment each other and it's good to know both.

My un-educate opinion on the matter is that you can get a much cleaner scribe, if you cut the pins first. This is to say that the tails will be marked on the long grain, and the marking knife is much easier to draw in tight.

However, for half blind it's much easier to cut the tails first, so it depends on the style that you prefer to use.

I like Frank Klausz's method which uses little measuring, for practice, it really helped to make me more comfortable cutting them. Also doesn't hurt to try cutting tails first, without marking them. When I think of Klausz, his style is to cut them by eye, because it doesn't matter anyway...the entire fit of the dovetail is how well you cut to your line, on the second piece (be it tails or pins), you need to mark your 2nd piece from the 1st.

For actual projects I prefer to measure them out though. That I would do more like Rob Cosman, with some personal mods.

I am having difficulty scribing a clean shoulder line. I suspect it is my marking guage. I'm using an inexpensive guage with a pin. Any suggestions or should I get a guage with a wheel?Make the tip oval shaped. Use a small diamond stone, (little folding keychain fob thang, about $10 at Woodcraft). Round it over but hone it thin on the diamond stone so it is more like a knife blade running around the tip. The trick is to keep it small enough so you can still get into a corner, but a nice area to cut with. If you have a traditional marking knife with a pin, those can be filed. Sometimes it's good to have the pin, depending on the wood (i.e., hard and dense).

Cutting the pins goes pretty well, its the tails that are tough. When I scribe the tails, the knife marks are on the inside of the piece. I then scribe the end grain with the dovetail marker, and try to make my cut folowing those two knife marks. My tails turn out tight on the inside, but loose on the show side (you can see the gaps). I guess I'm not quite getting the angle right.This is where experience will help. The more you cut dovetails, the more comfortable you'll get at it.

Any tips or words of wisdom would be appreciated! I have read numerous articles and watched the Tage Frid video.His video is funny, heh? He's really against cutting tails first, and says all the methods trying to secure the tails when marking in the end grain are "mickey mouse". He was quite a character himself...;-)

Remember that wood does make a difference also, Klausz's style works as he cuts mostly softwood, so he can pop the waste out with his chisel quickly. You can't do that in hardwood, it doesn't work like that.:D You need to see his video to appreciate it, he really cracks 'em out fast...

But don't listen to me, there more experienced craftsmen in this forum.

Stu Ablett in Tokyo Japan
09-04-2006, 7:50 AM
This post is very timely, I hope that Jonathan does not mind if I jump in on this thread.

I too am trying hand cut dovetails for the first time.

My first attempt did not make the photo cut, as I cut them the wrong way round............:o

The second attempt is here...........

46106

46107

The wood is Beech, maybe a tad hard to practice on?

I got some Luan today, that should be a little bit easier to work.

Does anyone have a good online tutorial?

The reason I'm learning now is that I've been asked to give a demo :eek:

A friend works at an international school here, he is the shop teacher at the school, and his wife is an ESL teacher, she wants me to do the demo during her English class. What the Heck you say...? Yeah, me too at first ;)

Well, she is trying to show the kids that when using English (or any other language for that matter) you need to have the right materials, the right tools and the proper technique etc. She wants me to make one butt joint and glue it, and nail it (I'm thinking of using CA glue for speed) and to make one hand cut dovetail joint, then compare the strength of the two joints, as well as the beauty of the two. This will take place 4 or 5 times in one day, on the 25th of this month, so I got to get better at these joints.

I have all the tools, I made a marking jig, I have good sharp chisels, and a good Japanese pull saw, so I'm just lacking the skills, needed, I hope that comes via practise.

Looking forward to seeing some more tips and trips, and again, Jonathan, I hope you don't mind that I joined in here on your thread.

Cheers!

Alan DuBoff
09-04-2006, 7:57 AM
Does anyone have a good online tutorial?I like to suggest:

George Huron's video (http://www.springharvestfww.com/dovetails.htm)

and

Phil Lowe's video (http://www.pem.org/luxury/furniture.html)

So many different ways, no right way, IMO. Well, yes there is, the right way is the way that works for you.

Stu Ablett in Tokyo Japan
09-04-2006, 8:41 AM
Thanks Alan, those are great!

they sure do make it look easy :rolleyes: :)

Mark Singer
09-04-2006, 9:53 AM
Johnathan,
You are off to a great start and practice is really all you need. If you sharpen the pin on the marking gauge to a knife like point rather then round it will track better. Then angle the gauge slightly as you pull. I used to cut pins first for for years and sometimes I still do. I think it is easier to scribe rom the tails...so I now cut tails first. I think you are just cutting too close to the line and if you cut a bit "fatter" and pare or rasp to fit trying by tapping and parring the shinney spots the dovetails will tighten. Your sawing looks very good! This is a big problem for many...you have that well under control. The tips in my Tutorial on Mitered dovetails may help...the same pointers apply to through and half blind dovetails...

http://www.wkfinetools.com/tUsing/ms/miteredDovet/miteredDov.asp

harry strasil
09-04-2006, 11:02 AM
Jonathan, for your first dovetails those are fine, now its just practice, practice, practice to refine your technique.

I actually use a veneer slitter gauge to mark the depth on my dovetails.

You might be holding the saw too tight or the set may be more on oneside than the other on your saw.

I always start my dovetail cuts at about a 45 degree angle as its easier for me to follow on one side of the line that way. I also make a small notch with my marking knife in the waste so as to get the saw started in the right place.

I use a square scantling and 2 to 4 clamps to hold the pieces from moving when marking the pins from the tails.

I use one of two marking knives to do the marking, the top one is an old design and the bottom one is my design I call a split birds tail marking knife, both are only sharpened from one side so no slanting of the knife is needed to get an accurate mark.

http://img.photobucket.com/albums/v81/irnsrgn/wood/markingknives2.jpg

Keep up the good work.

Jr.

Maurice Metzger
09-04-2006, 1:46 PM
The reason I'm learning now is that I've been asked to give a demo


Stu, isn't that a great motivator?

Jonathan and Stu, both your dovetails look great for first tries. I'm jealous, as I've been too busy lately to cut any.

For through dovetails I usually cut the pins first, but that's because I usually make the pins smaller than the tails as I like the way it looks. It's easier to mark the larger tails after cutting the pins.

Mark Singer posted a small but very important point a while ago - don't hold your dovetail saw too tightly. The loose grip will give you better feedback when you get off the line, as the saw tends to bind. Junior (Harry) also mentions this above.

Maurice

Stu Ablett in Tokyo Japan
09-04-2006, 2:01 PM
Harry, did you make those knives yourself?

Can I ask how thick the steel it?

Thanks for the tips and pointers, I have to go out of town tomorrow, so I don't get in any more practice.

Cheers!

harry strasil
09-04-2006, 2:14 PM
the birds tail is an old hand saw blade, the old style one is made from a 2 man saw blade.

Stu Ablett in Tokyo Japan
09-04-2006, 2:34 PM
Thanks for the info Harry!

Cheers!

Alan DuBoff
09-04-2006, 2:42 PM
Thanks Alan, those are great!

they sure do make it look easy :rolleyes: :)Stu,

It is actually pretty easy, once you get the hang of it. It all really gets down to the precision after you mark. I happen to believe it's good to practice, just cut dovetails. Wether it be for a project or practice, get some wood and start cutting them. Grab some scraps and have at it.

Others will tell you that they don't believe you should practice, that it's a waste of time, just build projects and the more you cut the joints the better they'll get. This is also true.

These are two different school, and I've seen Chris Schwartz mention he's also of the belief that practice is good. All of our milage varies, I happen to prefer some time with practice myself. In fact, doesn't hurt just to get a board, mark lines on it (straight and angled) and practice cutting to the line. I've done this will all types of various saws and it's helped me not only to learn my tools, but get more comfortable at cutting to the line.

NOTE: When you add in a western style handsaw, one that you can sharpen yourself, you can start to see the difference between a dull and sharp saw. Since your in Japan, I won't harp on that, as I know you have Japanese saws. There is something to being able to sharpen your own saw, and to touch it up before you work. I highly reccomend this to folks, it really helps people grow their skills, IMO.

Frank Klausz has a style he uses for drawer construction where he uses soft pine for the sides, and doesn't measure things, just does it all by eye. This is an excellent way to practice, IMO, as it frees you from thinking about or getting bogged down with measuring devices and details. All of that obfuscates things, IMO.

Remember, there is not one single way. There is not one way fits all, do what is right for you and what you feel comfortable with. It's always best to have an open mind rather than feeling that everyone should do things your way. This happens all to often on the inet.

James Mittlefehldt
09-04-2006, 5:51 PM
For what it's worth here is my opinion. I have tried at various times to cut both pins and tails first I cut tails first now.

Not sure if it is the only reason but one reason for doing it this way is that the harder line to cut are the tail lines, as they are angled. Since the first part you cut be it pins or tails serves as a template for the second part, then this makes more sense. The second part needs to be much more dead on accurate, so by doing the harder cut first it should insure success.

When I lay them out, I use a Veritas wheel marker by the way, I use Rob Cosman's method of doing the layout for the tails. ie set a pair of dividers to the approximate width you want for pins and tails walk it across the end of the board to be cut. When you have a width you are happy with mark out where the pins are to be. I use a square to make straight lines across the board I don't mark lines down the side to the line just on top.

With the lines marked, I then tilt the board in the end vise using a dovetail gauge to set the angle, then cut half the lines for the tails. then I tilt it the other way and saw the other half, this way you merely have to saw a straight line not an angled line, honest.

After that I set the pin board in the vise at the height of a plane on it's side and lay the wood across the wood and plane, mark out the pins, cutting them and chopping out in the manner of choice.

I should also add that I use a Pax dovetail saw filed rip. I also prefer to make much smaller pins than tails as I like the way it looks.

Hope that was of some help.

James

Mark Singer
09-04-2006, 9:39 PM
I agree that designing a layout of pins and tail spacing is very important once the dovetail technique begins to solidify. On drawers start wit a half pin at the top and bottom and try varying the width of tails and pins...there are many good examples here of such work on SMC

jonathan snyder
09-05-2006, 1:18 AM
Thanks for the kind words and encouragement!

Stu, Glad you jumped in, we will have to trade progress reports!

Thanks for the tip on filling the pin on the marking guage, I will try that.

I'm trying to hold the saw loosly, I picked that tip up from Harry, sometime ago. I guess I need to spend more just practicing time cutting to a line.

I will try to cut the tails first and see how it goes. As that is the harder cut, I guess it makes sense to do it first , even if Tage says its "Micky Mouse"

I went fishing today, so no time in the shop. I'll try another set again tomorrow!

Thanks again folks
Jonathan

Alan DuBoff
09-05-2006, 5:45 AM
I will try to cut the tails first and see how it goes. As that is the harder cut, I guess it makes sense to do it first , even if Tage says its "Micky Mouse"Remember, no matter what he thought, it's what you think. I personally mark tails first when I cut the joints for a project. I haven't practiced the Klausz way in a while, nowdays I mostly mark tails first. I don't find it mickey mouse myself, and find that having a marking knife that will slice the end grain helps, opposed to using an awl for instance.

If you cut pins first, an awl works good for marking the long grain.

Hans Braul
09-05-2006, 7:26 AM
Great post! I have been using the LV magnetic dovetail guide. It's a wonderful device that essentially makes it impossible to saw crooked. I know, it's kinda cheating, but so is a ruler (a good eye should really be all you need isn't it?) or a shooting board (can't you just plane straight by eye?). It still requires great care in chiseling and fitting, but is more likely to produce good results on the first try. With the guide, the choice of whether to cut pins or tails first is moot - both are marked at the same time on the ends of the boards (no need to mark the whole dovetail). I found it is critical to get a nice clean scribe line. I sharpened my pin to a knife edge and that seems to work.

Cheers
Hans

Stu Ablett in Tokyo Japan
09-06-2006, 2:46 AM
OK, I've been getting some more time into this, and the results are coming.

The biggest thing that I found I was having trouble with, was my accuracy.

I made up a striking knife, much like the one that Harry showed (thanks again for the info Harry!), I used part of an old hacksaw blade I had kept. The handles are ash, and I glued them on with CA glue, as I could not drill a hole in the steel.

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Works very well!!

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I also made a little square as well, as the large machinist square I have is a little heavy and hard to handle with the smaller pieces of wood I'm using for the demo.

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A dovetail angle gauge as well.

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The "Mirror" trick works well too.

I really found that changing to the Luan, and getting much better at marking things accurately, made a huge difference!!

cont............

Stu Ablett in Tokyo Japan
09-06-2006, 2:57 AM
............ OK, here are the results.........

46293

46294

46295

Well, does that look any better!

I've still got to do a ton more, so it becomes imprinted on my muscles, I figure another couple of dozen sets in the next few days, and I should be well on my way to having a handle on this.

Next I need to make a box, not just a corner!

Thanks for the help!

Cheers!

Alan DuBoff
09-06-2006, 3:51 AM
Well, does that look any better!I think they look great. Are you happy with the results? Nice tight fit, can't ask for more than that, IMO.

Stu Ablett in Tokyo Japan
09-06-2006, 4:19 AM
I think they look great. Are you happy with the results? Nice tight fit, can't ask for more than that, IMO.

Of course not ;)

But I'm working on it.

One of the things I need to work on is the time it takes, first ones took hours, now I've got it down to 20 minutes or so, need to make that even faster. It is a matter of cutting out unneeded steps and having a step by step in my head.

Cheers!

Mark Singer
09-06-2006, 7:37 AM
Stu,
Very nice! Speed comes with time......results are more important and yours are looking good! I would spend a little time laying them out and make the pins smaller than the details to add definition and scale... but really nice...

Stu Ablett in Tokyo Japan
09-06-2006, 7:57 AM
Thanks Mark, I guess I need a thinner chisel!

Cheers!

tod evans
09-06-2006, 8:23 AM
jonathan and stu, you guys are both doing great! handcuts are my favorite... i`m a tail first kinda guy....tod

Mark Singer
09-06-2006, 8:25 AM
For dovetails I use 1/8" , 1/4", 3/8", 1/2" , pin sockets

and 1/2" up to about 1 1/2 " for tail sockets

Stu Ablett in Tokyo Japan
09-06-2006, 8:38 AM
For dovetails I use 1/8" , 1/4", 3/8", 1/2" , pin sockets

and 1/2" up to about 1 1/2 " for tail sockets

Got that in Metric ;) :D

Thanks for the info!

tod, why does it not surprise me you'd go after the tail first.............. :rolleyes: ;) :D:D

Cheers!

Bob Oehler
09-06-2006, 11:53 AM
Like others have said you are off to a great start. I cut pins first on through and Tails first on blind. I have used the Frank Klaus method and it works. Maybe some time I should try tails first on the through dove tails and see how I like that.

Keep up the dove tailing and practice, practice, practice.

Take care
Bob Oehler

jonathan snyder
09-06-2006, 9:32 PM
Stu,

Those look GREAT! I cut another set last night, tried the tails first. I was not at all pleased with the result. I need to give it another shot though, I din not have much time and I rushed a bit.

I was thinking about trying the mirror trick, I guess I'll give it a try.

Jonathan

Stu Ablett in Tokyo Japan
09-07-2006, 3:12 PM
Jonathan, I've already found that the mirror is just a "Check" for me, I only look there to make sure I'm close to the line.

I decided to make 4 corners and a bottom on the last run............

46375

46376

46377

Sorry about the lousy pics, cell phone again........

That was fun, I'm just about set to do the Demo, and I have two more weeks! :D

I'm going to make up a kit of all the tools I need to do this, and I'm trying to think of a few things I could add to make the kids laugh, or at least smile :rolleyes:

One thing I'm going to go looking for is one of those "Snakes in a can" things, I figure I'll hand it to a kid and say....."Can you help me and open this....." should get a laugh or two :D

Cheers!

jonathan snyder
09-08-2006, 1:25 AM
Stu,

It looks like you have been cutting those all your life. I am envious!! I Have not had a chance to cut anymore, but I did pick up a small mirror today.

I started on a murphy bed this evening (no dovetails required)! I plan to practise more this weekend. I'll post a pic if I get any as nice as yours.

Hope you demo goes well, im sure the snake in the can will be a big hit.

Jonathan

Alan DuBoff
09-08-2006, 1:36 AM
Stu,

Looks good! Toss a lid on it, line it with cedar, and store those big stogies inside, instant humidor.:cool:

Stu Ablett in Tokyo Japan
09-08-2006, 2:58 AM
Stu,

Looks good! Toss a lid on it, line it with cedar, and store those big stogies inside, instant humidor.:cool:

Thanks Alan, but this one is already gone, my wife took one look at it and said "Oh, I have the perfect use for this......" and walked away! :eek:

GONE forever, I fear!

I want to get it back just for the demo, to show a completed unit...... I guess I could make another one;) :D

Jonathan, all it takes is practice, my skill (God knows) are nothing special, but if you get the time, and practice, you can do it for sure!

Cheers!

Jeff Craven
10-26-2006, 6:12 PM
My first dovetails: :D
http://img281.imageshack.us/img281/2066/dovetail2jl2.jpg

http://img118.imageshack.us/img118/3483/dovetail1ll1.jpg

Does anybody set the marking gauge less than the thickness of the wood & plane it down till both surfaces are even? That is what Ian Kirby's book recommends.

When I started cutting the tails, I cut on the wrong side of my pencil line, making one of my tails smaller than the other, I guess I was too excited to make some cuts with my new/old saw that I wasn't paying a lot of attention. Another question: The saw seems to be filed for cross cutting, when I get it refiled, should I ask for rip teeth?

http://img270.imageshack.us/img270/6240/jacksondovetailsawai9.jpg

Alan DuBoff
10-26-2006, 7:41 PM
My first dovetails:Nice job, looks good.

Does anybody set the marking gauge less than the thickness of the wood & plane it down till both surfaces are even? That is what Ian Kirby's book recommends.I sometimes will do that but will caution you that if you are using hardwood, you can end up making work for yourself by doing so. Leave too much and you'll be planing it down, so if you do that I would suggest a minimal amount.

Another question: The saw seems to be filed for cross cutting, when I get it refiled, should I ask for rip teeth?Depending on the tpi, it might not be a problem. Your saw looks like a 12" small tenon saw, or some might refer to it as a carcass saw. It looks like a Jackson, with an open handle, but tought to tell for certain in the pic, maybe it's a disston. Either way, those types of saws were typically about 12-14 tpi. The courser the teeth, the more difference you will see between a rip and a crosscut.

I reccomend rip for cutting dovetails as you're cutting with the grain most of the time. There are several cuts when you create a dovetail, and the end pins typically need to be cut across the grain, so a crosscut is preferred in that case.

Bottom line is that you can use either, but the majority of cuts are with the grain, and again, this all depends on the direction the board you're using is oriented. So, is this a trick question? There's a lot of variables to what type of saw to use, and size is completely a personal thing. Some folks prefer larger saws, and others prefer smaller saws. Wether for control, ease of use, effeciency, etc...everyone has their own reasons.

I use a pair of small joinery saws (http://wenzloffandsons.com/saws/adu/adu_0002.jpg), or what some would call dovetail saws. I like to refer to them as joinery saws because they're made for cutting joinery on stock up to about 6/4, and possibly 8/4, but 8/4 is starting to push it on a saw with less than 2" of depth. It really depends on what type of stock one uses, IMO, and I often work with 4/4. For very tough hardwoods, I wouldn't go more than 6/4 with my saws.

Keep cutting more dovetails, use the saw you have, but just keep cutting them and you'll get better at them. The more you do it, the easier it will get.

These were cut with those saws, very hard purple heart (can you say purple cement) and hickory. Both of these are pretty hard woods. The purple heart was milled down from flooring I have and is possibly some of the hardest wood I have in my shop right now. On paper the hickory is harder, but I can assure you, that is NOT the case. This picture was also before cleanup, and you can see the hickory tails are just a tad proud.

http://www.SoftOrchestra.com/woodworking/tools/bench_renovation/small_closeup.jpg

Jeff Craven
10-26-2006, 8:08 PM
Thanks for the advice, I'm really enjoying reading this forum.

It looks like a Jackson ... Yep, it's a 10 inch Jackson w/ 13 tpi. Right now it is my only backsaw, but I'm on the lookout for some more. Would you use a higher tpi for crosscuts than you would for rip cuts? I'm just trying to figure out what size saw to look for next.

Alan DuBoff
10-26-2006, 8:42 PM
Yep, it's a 10 inch Jackson w/ 13 tpi. Right now it is my only backsaw, but I'm on the lookout for some more. Would you use a higher tpi for crosscuts than you would for rip cuts? I'm just trying to figure out what size saw to look for next.Sometimes a slightly coarser crosscut was offered in the same size, so a 14 tpi rip saw may be the equivilant. I have a 12" open handle Jackson (http://www.softorchestra.com/woodworking/tools/saws/handsaws/jackson12/index.html), and a 8" open handle Jackson (http://www.softorchestra.com/woodworking/tools/saws/handsaws/jackson8/index.html), not sure what tpi they are off the top of my head, but I know the 8" is definitely rip, and it's about 14 or 15 tpi. The 8" is very close to what folks refer to as a dovetail saw and has a slightly thinner plate (why I saw it's close to what folks refer to as a dovetail saw).

Hah! Those gallery buttons are screwed up, ignore that, but I can count 15 point to the inch, so 14 tpi, I think that's how it works...(that's for the 8"). No ruler on the 12"...:( Hard to tell what the 12" is, but I think it's rip.

Funny, I don't have all of my saws on the web, but do have those Jacksons.;)

Chuck Stanford
10-27-2006, 12:16 PM
Pins first, because you can use the marking implement of your choice. I use a pencil. If you mark tails first, and like small pins, then you have to use a marking knife when marking the pin board. You have no choice. I don't like not having choices, do you? If you mark pins first you can still use a marking knife on the tail board if you wish. Regardless of which you do first, the first half of the joint can always be marked out with a pencil.

I find it easier to mark pins first on large workpieces for carcase work as well.

Your dovetails look pretty decent. Just keep practicing.

Hank Knight
10-27-2006, 3:15 PM
Jonathan,

If you're having trouble keeping your chisel vertical when you're chopping, try this:

Use a piece of thick stock as a chisel guide block; 5/4 thick is fine. Joint one edge straight and square. Glue a piece of sandpaper to the bottom to keep it from slipping. Saw the pins or tails and then clamp the block on top if your workpiece, I.E. sandwich your workpiece between the guide block and the bench. It's also a good idea to place a piece of plywood or masonite under the work to protect your bench. Make sure the square edge of the block is lined up exactly with your depth mark. Rest the back of your chisel against the block while you're chopping. It will keep your chisel vertical and lined up with your depth mark. Works great. I find it easier to chop half-way through, turn the workpiece over and finish from the other side. This gives you a nice clean base line on both sides with no blowout.

I cut tails first on through dovetails and pins first on half-blinds. I don't know why except I learned that way. On half-blind dovetials, most of the work goes into cutting the pins, and I find it easier to pare the tails to fit the pin sockets rather than the other way around. As you can see from the responses, this is a personal preference thing.

I mark with a knife, then run a pencil down the knife mark and erase the pencil line. There will be enough carbon left in the knife mark to give you a nice crisp, easily visible line. On dark wood I use white chalk for the same effect. I also cut mine with the ends of the pins and tails a little proud, say 1/32. It's easier for me to plane down the ends than to plane down the whole side of the work. This method gives you a little added benefit: when you plane down the ends, you naturally crush and deform the end-grain wood fibers a little. This can hide some minor gaps between the pins and the tails.

Your efforts look great, much better than my first ones. Keep working on it. Dovetails are not as hard as they look and it's not hard to get good looking ones with a little practice.