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Paul Incognito
04-11-2010, 5:55 PM
I tried cutting some dovetails today, the results are pictured below.
This is my first attempt. I had some poplar laying around and figured I'd give it a try.

Things I learned:
Lay out with a knife. A pencil isn't precise enough.
Make sure to touch up the chisel edges before choping and paring.
Chop the outside first, that way if the other side blows out it's inside the box.
Walk away. Take a break if it starts getting frustrating.

Questions:
Is a guide block on the baseline for paring a good idea? I didn't use one.
Is it necessary to undercut the base, similar to what you do with tennon cheeks?
Do you chisel a v groove on your layout lines to guide the saw?

I'd love some feedback.
TIA
PI

Bruce Page
04-11-2010, 6:49 PM
Paul,
Excellent “first attempt”. I am far from an expert but in my opinion, a nice square guide block helps a lot.
I found that a sharp edge on the block really helps to align with the layout line. I added some 180 grit PSA paper to the bottom of the block to keep it from moving when I clamped it down.

gary Zimmel
04-11-2010, 7:20 PM
Looks like you are well on your way with the hand cuts Paul...
I don't use a block for chopping to the baselines. My chisel is guided by the scored line my titemark leaves.
When cleaning up to the baseline I cut half way from the back side and then finishing from the front. This will prevent blowout. If one uses a small square you can see if you have any high spots on the bottoms and if you do one can pare them flat.
Lastly other than the baselines and pin layout all of my other layout lines are made with a pen not pencil.
Great job again on those first dovetails.

Russell Sansom
04-11-2010, 8:09 PM
We're all going to have a different take on your body of questions. Here's mine:

1) I find the guide block attractive every time I see it. Every few years I try it again. But it's just too fiddly and time consuming for me. The biggest problem for a beginner is avoiding wedging the back of the chisel on the very first chop and ending up "behind the line." A guide block will help with that. My alternative is to cut a little guide groove at the baseline. Just a VERY little tap to take out a wedge, then take 3 or 4 shallow wedge cuts a little distance away from the base line. This way that first downward chop won't wedge your chisel back. I think Gorman's notebook shows this pretty well.

2) You actually have to undercut by a degree or so in order to get a fit. Some people recommend only undercutting the center, leaving a "land" of, say, 1/8" .
3) It won't work to cut a guide groove with the grain. On the rip sawing part of the exercise the precision comes from practice and knowing what you want. A great exercise: take a wide offcut of poplar and mark out, say, 15 lines as if you were going to cut a bunch of random pins. Then just practice sawing down to your scribe line. Repeat with tails. A couple dozen repetitions should up your confidence. There simply isn't any substitute for experience.
4) I can't imagine cutting dovetails without scribing the baselines with a marking knife. When you lay out with a knife there is a riddle about cutting all the way across the board on the outside; the part that will show. On some of my practical cabinetry I just let the line show. The options are to cut the mark out line very shallowly and plane it off, or mark only where you are going to chop. Both options have their down side.

Jim Koepke
04-11-2010, 9:28 PM
I tried cutting some dovetails today, the results are pictured below.
This is my first attempt. I had some poplar laying around and figured I'd give it a try.

Things I learned:
Lay out with a knife. A pencil isn't precise enough.
Make sure to touch up the chisel edges before choping and paring.
Chop the outside first, that way if the other side blows out it's inside the box.
Walk away. Take a break if it starts getting frustrating.

Questions:
Is a guide block on the baseline for paring a good idea? I didn't use one.
Is it necessary to undercut the base, similar to what you do with tennon cheeks?
Do you chisel a v groove on your layout lines to guide the saw?

I'd love some feedback.
TIA
PI

Paul,

For a first attempt at hand cut dovetails, those are not too bad. I have been doing them for years and still come up with ones that do not look much better than yours. I keep trying.

I use a knife or a pencil. When using a pencil, it is very sharp. Mechanical drawing pencils are nice, but it is getting difficult to find leads anymore since drafting is mostly done with computers these days. When a knife is used, I often go over the line with a pencil to make it more visible.

One thing that taught me a lot about this was watching Kevin Glenn-Drake giving a demonstration of his Kerf Starter. To allow for saw blade width and all he used feeler gauges and squares to set up the lines. This made the light bulb go on and made me realize that the pencil line when drawing the pin positions from the tails is outside the waste area and should not be cut.

A lot of people find a guide very useful. If it works for you, then it is useful. One of my findings is the bevel of the chisel tends to push the chisel. So I do start to cut a little above the line and then come down. If I do not saw out the waste, then I will chop a trench half way through. A little at the line, then come in from an angle. Repeat this a until about half way through. Then when all the tails or pins are done, the board is flipped and the same is done from the other side. This leaves part of the waste in place to support the waste from the other side when the board is flipped.

You are on the right track of working from the outside in. This leaves cleaner lines on the outside. Cut your tails and pins with the saw and the chisel from the outside.

Once you get used to starting a saw cut you will find cutting guide notches to be extra work.

Some folks like to undercut the base. It doesn't hurt and it is a touch easier. Another little bit of help is to chamfer the inside edge of the tails so the opening will fit a little easier on the pins. Just a little is all that is needed.

I also like to cut both the pins and the tails a bit proud and then plane them down. Work from the outside in to avoid blowing out the end grain when planing. Some are on video with proud pins and tails and hitting them with a hammer to fill in the gaps. Others will saw a kerf along the lines and then glue in slivers of waste. If the slivers match the wood used, it will take a close inspection to find them.

Finally, many find it advantageous to rabbet the inside of the tail board about 1/32 - 1/16. This helps to hide the inside of the joint and also serves as a baseline of the tails to register against the pin board when marking the pins.

Keep trying and let us know how you do on your next set.

jim

Rick Erickson
04-11-2010, 9:57 PM
I tried cutting some dovetails today, the results are pictured below.
This is my first attempt. I had some poplar laying around and figured I'd give it a try.
PI

Wow Paul - superb job for your first dovetails. I would say my 10th attempt looked like those. Great Job.

Questions:
Is a guide block on the baseline for paring a good idea? I didn't use one.
No - this will just slow you down. A nice scribe line should be all you need.

Is it necessary to undercut the base, similar to what you do with tennon cheeks?
A very slight undercut is nice but as others have said don't undercut all the way to the edge. If you do when you go to plane down the sides you may start to broadcast through near the tails/pins.

Do you chisel a v groove on your layout lines to guide the saw?
No V groove is necessary. If you have a good marking knife you should be able to split the line. Pinch the wood with your fingers and ride the saw on the edges of your fingers.

Jim Barrett
04-12-2010, 12:12 AM
I cut my dt's pretty much the way Gary and Rick do...we are all Rob Cosman disciples :)
One thing I would say is use a very light touch when you start your saw kerf...just "kiss" the wood...

Jim

Don Dorn
04-12-2010, 6:07 AM
I've tried the Cosman way because I like those skinny pins. Being a student of Klausz who has done it that way for a few years, the tails first was a tough concept for me. It worked, but there must be something I'm missing because I have difficulty seeing the marking gauge line and am not a fan of trying to line up the wood to make those marks on the pin board. With pins first, I can lay one on the edge of another on the bench.

For some reason, I don't understand the fret saw business. Cutting out the majority isn't my issue - it's only having that little bit left and getting it out without messing up the marking gauge line. I guess I'm so used to chiseling back to the line that it's just a matter of disipline. Like I said, I must be missing something so I simply went back to the Klausz way of pins first, but decided to make them skinny. Same result -

RC certainly has made a contribution to the craft, I'll definetely give him that. Guess this student just has two left feet when it comes to his method.

Paul Incognito
04-12-2010, 6:58 AM
For the advice and the kind words.
I'll keep trying and let you see the results.
PI

Jim Barrett
04-12-2010, 8:36 AM
Don...doesn't matter how you get there...as long as you do :)

Jim

David Weaver
04-12-2010, 9:07 AM
Charlesworth has a good trick for paring to the line without using a guide block. Make your marking gauge line fairly deep on the edges of the board and use that as a guide for your chisel.

Feel what's level to the top of the board by first placing the chisel across the tails, grasp the chisel without moving its incline, keeping it parallel to that, and move it to your marking line and pare.

Obviously, if you have a lot of waste above the line, pare some of it off first before you go for the gold on the marking line.

Once you get used to doing it, you'd actually be able to do a good job with a pencil, just keep to the inside of the pencil line when sawing whatever you're sawing second. The issue, though, is getting a pencil that will mark inside small pins that you'll probably want to do as proof you did the dovetails by hand. I still use a knife, and cut tails first, but I'd probably use a fine point pencil if I could get one that would fit between the pins, because it's easier to mark with - one scribble and no need to check if the line is deep enough and make sure I didn't leave some of it in the tail instead of on the board with pins.

Those look a lot better than my first ones did.

Rick Erickson
04-13-2010, 12:25 AM
RC certainly has made a contribution to the craft, I'll definetely give him that. Guess this student just has two left feet when it comes to his method.

Funny Don. I tried the pins first method and tripped over myself. I just couldn't do it - probably because I learned the Cosman way (with no prior experience) and that was what stuck. I think it takes more skill to do pins first - that's probably why I have difficulty with it :)

Jim Koepke
04-13-2010, 1:28 AM
Funny Don. I tried the pins first method and tripped over myself. I just couldn't do it - probably because I learned the Cosman way (with no prior experience) and that was what stuck. I think it takes more skill to do pins first - that's probably why I have difficulty with it :)

I think the real skill is in being able to keep the pin board square in two dimensions when marking the tails. With a shallow rabbet on the tail board alignment is a bit easier with either pins or tails first.

One of the strangest things happened to me one time when practicing dovetails. My normal method is to cut tails first. One time pins first was tried. They came out better than doing them tails first. Of course, there were no pictures and it only happened one time.

My saw has spoiled me as far as depth of cut is concerned. It has a movable back so the depth can be set. With a bit of care and practice it is not too difficult to stop before crossing the line.

jim

John A. Callaway
04-13-2010, 12:30 PM
The biggest help I have done for myself is getting the videos. We all know the "degree" which i am referring too . ( he is fine with me, I like his methods...but some people are butting heads with him right now )

Secondly would be lighting. Getting a lamp or desk light or something to light up your work. When you can really see what you are doing, you will improve. Specifically, stopping at the line.

Rick Erickson
04-13-2010, 1:20 PM
The biggest help I have done for myself is getting the videos. We all know the "degree" which i am referring too . ( he is fine with me, I like his methods...but some people are butting heads with him right now )

Secondly would be lighting. Getting a lamp or desk light or something to light up your work. When you can really see what you are doing, you will improve. Specifically, stopping at the line.

Good advice on the lamp John. This is a must. Also good advice on the 'degree'. He gets more heat on this site than any I've ever seen.

Don Dorn
04-13-2010, 2:19 PM
I'm not happy having difficulty with the Cosman method - but if I'm doing a drawer or something where strength is the priority as opposed to looks, the Klausz way works best for me. No marking, everything is just by eye and still looks good and I can get a 5/8" pine drawer done from beginning to end between 30 and 40 minutes.

The two things that get me on the Cosman method is simply not being able to see the marks I make through the tail board on to the pin board - they don't seem to show up or if they do, it's just barely a faint line. The other was mentioned before in that when done with the fret saw, there is very little "meat" left and in trying to get it out, end up shoving the marking gauge line deeper because I can't "re-enforce" that line like you normally do before you chop.

Ah well - I'll get it one of these months.

Jim Barrett
04-13-2010, 3:16 PM
Don,
I think cutting dt's is like sharpening...once you find a method you like...stick with it. You'll just get better the more you do it.

Jim

rob cosman
04-13-2010, 3:42 PM
Hi Don, here are a few suggestions from the "degree" guy, I can feel the arrow points being sharpened! Good thing I thrive on controversy. There really aren’t any marking knives available that I like. They are too sharp, meaning the mark left is too hard to see. They are round handled so you can’t tell by feel the orientation of the blade when working in tight places, and the worst ones have such thick blades they are no good for small pins and you lose that "feel" which tells you when you are laying against the side of the tail. I am working with that other notorious company, IBC, on a custom knife patterned after the red one you see in my DVDs. A few more characteristics I will save for the final product. In the mean time you may have better results with the small blade of a Swiss Army knife. Use a bench lamp to shine across the end of the joint, it will drop shadows in the knife marks making them much easier to see. The other thing to try is to shoot the end of your boards with a plane. Much easier to see knife marks in the planed surface over a table sawn one. Now what you need is a good blade and chip breaker in that old plane.....................Just Kiddin!

As for the fret saw work, the tool I consider second to the dovetail saw in executing a great joint is the marking gauge. It should leave a precise, clean and crisp line that will grab your chisel tip regardless of how much material is left on the waste side. The brand I recommend on my DVD has changed, the cutter now has a much more blunt angle and doesn’t cut like the old ones. I now have my own brand and soon we will offer blades that will fit other brands, these have very acute bevels and come sharp ready to go.

One final thought is your chisel sharpening. I have taught thousands of folks dovetailing and the biggest problem I encounter is the sharpening and initial prep of their chisels. If they have flat backs and are truly sharp they will grab end grain at the most severe angle. Check this. Good luck, email me if you don’t want to go public with such a villain!:cool:
Rob, the other Rob

Rick Erickson
04-13-2010, 5:10 PM
Rob, what is the ETA on the marking knife?

Tony Shea
04-13-2010, 6:11 PM
I agree with Cosman in that marking knives really make things hard for me when tansfering cut tails over to the pin board (half blinds) or pins over to the tail board. Most I have tried seem to lack the ability to accuractly get into the confined spaces of the board that is the template. And if they do fit in the space I usually struggle with the feel of the knife against the template board. I seem to like my exacto knife the best for marking but due to the angle of the knife it tends to cut slivers off the template board as I am tranfering marks. But I like the thin blade as it allows me to get extremely tight against the template board and make the mark almost underneath the reference board. This puts my marked line in a place that actually is going to be cut as it ends up in the waste area. I would like to come across the right knife for marking out dovetails someday but will probably have a fortune invested in the mean time. Funny how my least expensive ($3) exacto knife has become my got to knife. I'm still young and have great eyes so the fine line is perfect for my uses. I sometimes chisel my pencil on sandpaper and go inside the knife line to help me see it, chalk would work as well. Another great tool is the wheel marking guage. Creates very crisp baselines for the chisel to register in.

Jim Barrett
04-13-2010, 7:10 PM
As I mentioned in this thread,
http://www.sawmillcreek.org/showthread.php?t=133333
I use my little swiss army knife for marking my pins. It works really good...not too sharp and not to dull. It leaves a nice "v" groove in the wood where I can "attempt" to split it with my dt saw.
Now the blade is a bit too thick for very narrow dt's so I then refer to my exacto knife with ok results. It is a bit too sharp and can grab or cut into the tail I am tracing.
I look forward to Rob's marking knife.
Jim

rob cosman
04-13-2010, 7:11 PM
Hi Rick, Brian says a few months should do it.
cheers
rob

Jim Koepke
04-13-2010, 7:35 PM
Use a bench lamp to shine across the end of the joint, it will drop shadows in the knife marks making them much easier to see. The other thing to try is to shoot the end of your boards with a plane. Much easier to see knife marks in the planed surface over a table sawn one.

Rob, the other Rob

+1 on the bench lamp. If need be, get one of the cheap ones with the scissor arms and make up a block to clamp it or fit it to the bench.

I would never have thought of mentioning shooting the end grain since I never thought of cutting dovetails without shooting the end grain to square it up. Just goes to show what we do without thinking about it.

For marking, I made my own knife from a piece of saw blade. It can fit into real tight spaces and since it is only beveled on one side it is easy to control inside one half of a dovetail.

148102

When a pencil is used, it is usually an old mechanical drafting pencil with a very sharp point and the lead extended.

jim

Eric Brown
04-13-2010, 7:44 PM
Next time y'all get a chance, look at Glen-Drakes kerf starters.
Instead of a knife line or a dull knife groove, just use the kerf starter to make a groove that not only matches your saw blade width but allow the saw to literally drop into where you want to make the cut.

He has a video available that shows it in action.
Well worth a look.

http://play-glen-drake.com/v-web/ecommerce/os/catalog/index.php?cPath=27&osCsid=919901498ebeae1414bb3a48ba85c265

Eric

Jim Barrett
04-13-2010, 8:53 PM
Eric,
I went to the LN handtool event and Glenn Drake was there showing his wares.
I don't know....tried his handsaw and I found it a bit awkward...of course it was a very different feel for me but hey someone else might swear by it. It seemed too "calculated" for me...but that is only me. If someone is using Glenn's methods and is happy with their results...excellent!

Jim

Don Dorn
04-13-2010, 10:58 PM
Hi Don, here are a few suggestions from the "degree" guy, Rob

Rob,

Thanks for interjecting - I will take your suggestions and try them. I hadn't thought of the Swiss Army knife, and will shoot the edges. Fortunately, the chisels are in good shape.

Not sure why I feel the need to master both ways, especially when the pins first way has worked well for along time, but as I said, you really caught my attention with those skinny pins and I should be able to do it in the manner so many of your students have mastered it.

Jim Koepke
04-14-2010, 2:18 AM
Eric,
I went to the LN handtool event and Glenn Drake was there showing his wares.
I don't know....tried his handsaw and I found it a bit awkward...of course it was a very different feel for me but hey someone else might swear by it. It seemed too "calculated" for me...but that is only me. If someone is using Glenn's methods and is happy with their results...excellent!

Jim

I do not use his methods but I did see how they work and adapted the knowledge gained to improve my own methods.

jim

Jim Koepke
04-14-2010, 2:23 AM
Not sure why I feel the need to master both ways, especially when the pins first way has worked well for along time, but as I said, you really caught my attention with those skinny pins and I should be able to do it in the manner so many of your students have mastered it.

What ever way works is fine, but it is also a benefit to try both ways.

It is kind of like being able to write or mark a line with either hand. Sometimes it is just convenient to be able to do it another way.

jim

Tony Shea
04-14-2010, 9:51 AM
I agree that learning both ways is a huge advantage. Specifically with half blinds. I've always learned to do pins first and still continue this method when doing through dovetails, it just suits my style. Once working on a project that requires some half blinds I have come to the conclusion that doing tails first with these is the absolute way to go. It just makes marking out the boards much easier. One would think I would just convert my methods for both types of dovetails to tails first, but I just don't feel natural that way I guess. Therefore learning both methods is def. a huge advantage and once you get confortable with both you can choose which one you ultimately feel the most confortable with.

Scott Stafford
04-14-2010, 11:54 AM
While I don't wish to rekindle any controversy. I think that the hand tool community owes a great deal of thanks to Rob Cosman. He indeed has taught thousands of woodworks, mostly amateurs, that hand tools are indeed very valuable in today's world and many times perform functions that no machine can match.

Without Rob's videos and extensive classes many of us would still be scoffing at hand tools... mostly out of ignorance and intimidation. His influence and teaching has greatly expanded the popularity and awareness of this and other hand tool forums. As an end result I have met numbers of people who share my interest in using hand tools. Many have become close friends. And, I have learned many valuable things from each and every one of them has.

I wish to thank everyone here for all of their postings and input, but if it wasn't for the handful of the hand tool advocates spreading the word in classes and media, many of us wouldn't be reading this.

Thank you Rob Cosman, Christophe Schwarz, David Charlesworth and many more for your continued efforts to educate us. I don't mind paying for it.

Just my opinion. Thanks for reading.

Scott in Montana

Rick Erickson
04-14-2010, 7:03 PM
Well put Scott.

Mark Kosmowski
04-14-2010, 8:22 PM
Very nice work! Keep it up.

Tony Shea
04-14-2010, 8:37 PM
I agree 100% Scott. Couldn't have said it better myself.

Bill Whig
04-14-2010, 9:03 PM
The biggest help I have done for myself is getting the videos. We all know the "degree" which i am referring too . ( he is fine with me, I like his methods...but some people are butting heads with him right now )



Sorry, I must have come in late. Which videos are you referrring to?

Bill

Rick Erickson
04-14-2010, 9:41 PM
Sorry, I must have come in late. Which videos are you referrring to?

Bill

Bill, Rob Cosman sells numerous DVDs on different topics. The ones referred to in this thread are his Dovetail ones. You can find them on several websites (craftsman studio, woodcraft, robcosman, etc.). There are many ways to learn to cut DTs but IMO none are better. If he can teach a stooge like me to cut them I willing to say anyone can do it.

Bob Warfield
04-14-2010, 10:28 PM
I too have Rob Cosman's full set of dovetail videos. I can tell you positively that for me anyway, I learned much more watching a master than anything I ever read about the subject. I see the cost as just another tool that I couldn't live without. After all aren't most of us "Tool Junkies"!
Thanks,
Bob Warfield

Jerry Gerard
04-14-2010, 11:58 PM
Hey Paul

Those first hand done dovetails look great , keep doing what your doing. See ya at the next club meeting .

Regards
Jerry ( First State Woodturners )