Technique for half-blind dovetails

[Daniel Rode]

I took out the router dovetail jig, blew off the dust and made a test joint. After looking at the results (that I used to think looked OK), I packed it up for sale.

My hand-cut dovetail skills are still pretty green. I've had some practice with through dovetails and I can make them reasonably well. I tried a half-blind for the first time this weekend.

I need to make a pair of 2 1/2" high drawers with QS white oak fronts and clear pine sides. The layout I want features 3 tails, 2 3/8" pins and 2 1/4" half pins and a 3/16" web.

The tails are no problem. I'm happy with where I am marking out the pins and sawing the 45 degree cuts. Removing the waste is where I've had some issues. With heavier half pins or softer wood, I can use a card scraper placed in the saw cut to finish the line all the way down. Place an un-sharpened scraper in the cut and whack it with a hammer. Cleaning out the remaining waste from the sockets is pretty easy and fit well.

However, I want to use 1/4" or even 3/16" half pins and oak is hard and brittle. Even with support from a clamp, I'm getting splitting almost every time. The simple answer is to hog everything out with a chisel or maybe drill out some of the waste to speed things up. I've practiced this some as well. Although it's slower, I can do it well enough without breaking anything. FWIW, I don't own any skew or fishtail chisels but I seem to be able to get the corners clean without them.

Is there any other tips I should try for clearing the waste from the sockets? I'm more interested in repeatable quality that speed. I can take as much time as I need :)

[Joe McMahon]

After marking the pins, cut the edges on a diagonal up to the lines with your dovetail saw. Then take a card scraper, put it into the saw kerf and tap it down, straight into the joint. When you are done, you should have the opposing two edges completely cut. Now all you have to do is chop out the material

[Daniel Rode]

That's the part that is spiting breaking the half pins. Thin half pins and hard, brittle oak are apparently not a good match for the card scraper trick.

After marking the pins, cut the edges on a diagonal up to the lines with your dovetail saw. Then take a card scraper, put it into the saw kerf and tap it down, straight into the joint. When you are done, you should have the opposing two edges completely cut. Now all you have to do is chop out the material

[Judson Green]

I took out router dovetail jig, blew off the dust and made a test joint. After looking at the results (that I used to think looked OK), I packed it up for sale.



Ha! I'm almost exactly in the same place. Started just last week practicing hand cut dovetails. Maybe its beginners luck but they don't look too bad. Will probably be selling my jig too.

[Tom Vanzant]

IIRC, CS drilled/bored out much of the excess, then pared to the mark. Derek Cohen used a router to do the same in Jarrah, but has also used the scraper trick. Some scrapers are too thick and cause splitting even when backing up the half pins with clamps, so thinner is better. As Jim K says, YMMV.

[Mike Henderson]

Half blind dovetails are easier than through dovetails because very little shows - much less than with through dovetails. And dovetails are so strong that you can do a few things to give you a better fit without greatly affecting the strength.

My suggestions:

1. On the back of the tail socket, make sure you cut inward a small amount so that when you put the tail board and the pin board together the tail is not held out.
2. You can over cut the pins everywhere they won't show. So along side the pin, you can cut inward which will make your tail socket wider in the back than in the front. Only the fit at the front will show.
3. Along the bottom of the tail socket, you can cut downward a small amount. The main thing is that you don't want a hump or an upward slope at the bottom of the tail socket because it will push the tail out and mess up your fit.

I have a tutorial (http://www.mikes-woodwork.com/Half-BlindDovetails.htm)on my web site on how to make half blind dovetails.

Mike

[Pat Barry]

Half blind dovetails are easier than through dovetails because very little shows - much less than with through dovetails. And dovetails are so strong that you can do a few things to give you a better fit without greatly affecting the strength.

My suggestions:

1. On the back of the tail socket, make sure you cut inward a small amount so that when you put the tail board and the pin board together the tail is not held out.
2. You can over cut the pins everywhere they won't show. So along side the pin, you can cut inward which will make your tail socket wider in the back than in the front. Only the fit at the front will show.
3. Along the bottom of the tail socket, you can cut downward a small amount. The main thing is that you don't want a hump or an upward slope at the bottom of the tail socket because it will push the tail out and mess up your fit.

I have a tutorial (http://www.mikes-woodwork.com/Half-BlindDovetails.htm)on my web site on how to make half blind dovetails.

Mike
Mike - that tutorial is great - we should have it as a Sticky for easy reference. Maybe an Admin can help with this??

[Jim Koepke]

I took out the router dovetail jig, blew off the dust and made a test joint. After looking at the results (that I used to think looked OK), I packed it up for sale.


Will probably be selling my jig too.

Wait, you mean people will actually buy those things? My conscience might bother me for selling mine to an unsuspecting buyer.

Derek Cohen also has some information about cutting half blind dovetails on his site:

http://www.inthewoodshop.com/Furniture/index.html

Using the page "find" feature it appears there are 9 items that have "dovetail" in the title.

I am not a great dovetailer, but mine work out okay. Use half blinds in a set of drawers built not too long ago:

283904

On the third draw from the left you can see one of the half blinds.

Burl is a pain to work, but it looks nice.

jtk

[Christopher Charles]

Hello Dan,

I've been doing some wasting out with a DP (though I'm sure it saves all that much time) and then using skew chisels for paring out the corners rather than using a scraper (mostly because I have the chisels, but haven't found a thin enough piece of scraper/sheet metal for the kerf of my dovetail saw). The alternative to skew chisels is a very thin chisel (1/8" or less) to get into the corners. Also, you can leave the pins a wee bit fat--the pine will mash around them for a good tight fit.

Good luck.

[Brian Holcombe]

Mike,

Don't think I've had the opportunity to say this previously, but I refer to your tutorials as a refresher quite regularly, they are fantastic. Between you, derek and SMC I'm spoiled.

[Joe Tilson]

After seeing this I mines for sale too. Sorry Jim, I guess this old man is heartless, but now I need the money to buy the chisels.

Mike, Thanks for the tutorial. Very good, very good indeed.

[Daniel Rode]

I bought mine 7-8 years ago. I used it a few times but I never really got the results I hoped for. Don't get me wrong. It works, I just don't like the the results. The new owner will probably love it :)


Wait, you mean people will actually buy those things? My conscience might bother me for selling mine to an unsuspecting buyer.

[Daniel Rode]

Mike,

I've read both of your DT tutorials several times. (thanks again) That's essentially the way I'm doing them.

The card scraper trick is an addition, but after my 3rd broken half-pin, I didn't think it was saving me much time :)

[Daniel Rode]

I experimented drilling out the waste a bit this weekend. By the time I get the DP setup and drill the sockets, I could have chopped them by hand. If I were doing larger sockets or a large number of them, it would be worth the setup time.

I have a 1/8" chisel and it's great for getting into the corners. Then I relieve the bottom corners of the tails and I'm good to go.


Hello Dan,

I've been doing some wasting out with a DP (though I'm sure it saves all that much time) and then using skew chisels for paring out the corners rather than using a scraper (mostly because I have the chisels, but haven't found a thin enough piece of scraper/sheet metal for the kerf of my dovetail saw). The alternative to skew chisels is a very thin chisel (1/8" or less) to get into the corners. Also, you can leave the pins a wee bit fat--the pine will mash around them for a good tight fit.

Good luck.

[Christopher Charles]

Mike-- Forgot to say thanks and kudos to you for the tutorials as well. I've also really enjoyed seeing all of your marquetry work.

Dan, sounds like you're set on chisels, and I agree about the set up time: only worth it if i'm doing more than ~3 drawer faces. Let us know how it goes.

C

[Judson Green]

Some good YouTube videos too.

Sellers, Bullar and Klausz