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View Full Version : Thoughts on my first half blind dovetails.



Scott Winners
01-06-2022, 1:04 AM
1. We may be masochists. In all fairness cutting this joint required my total concentration, similar to technical scuba dives when I was a younger man. There is the irony of relaxation when a hobby requiring total focus requires letting go of career stress, but, ummm, yeah.

2. kerfing chisel


Regarding kerfing chisels: I'll probably get struck down by the internet woodworking gods for this, but I have a 6" drywall knife that fits *perfectly* in my Veritas dovetail saw kerf.

Kudos to Daniel. I used my Veritas dovetail saw to kerf up some scrap, and carried it to both team orange and team blue homestores. On the one hand I am willing to believe this is a happy accident and Rob Lee did not intentionally set out to make a dovetail saw that could accept a eight dollar knife for drywall mud as a kerfing chisel, but the more stuff I buy from LV/V the more happy accidents I find. If they start selling powerball tickets from Ottowa I am going to load up. It took me four bites to finish my saw kerfs with the mud knife kerfing chisel, but it got done with no other drama.

3. The Narex bevel edge chisel set are a pretty good value at $20 for the L/R pair. Yes, it takes a while to get the backs flat compared to a more expensive chisel. But that is one and done. Once the backs were flat I freehand hollow ground the bevels on mine to 25 degrees on my grinder, and then used my LN guide (I have the left and right jaw sets at 30 degrees) to put on a secondary at 30 degrees with 30 degree skew and they pare just fine in American Beech. You guys that do this joint a lot know perfectly well I did most of my paring with a regular easy to sharpen square chisel, but the Narex pair were lifesavers for the inside the corners on the pin board- and limit how small I can make my tails because those inside corners in the sockets really did fly in on that last tornado from Kansas. If I end up doing many more of these I will look for a pair of fishtails, or an ambidextrous fishtail, so I can tighten up the spacing a little bit.

4. If Derek Cohen and his wife ever visit Alaska I am going to get him drunk and give his wife enough beer to keep him drunk until they fly home. I have watched about sixteen thousand and four you tube videos about half blind dovetails and finally just typed "IN" into my browser to take me to that website down under where stuff gets done efficiently and effectively the first time. I'll probably cook for that boy too, now that I think of it.

5. I got gaps. But I have consistent gaps and I am sort of in a corner. I have 15 inches to spare on my pictured pin board. I have one scrap of remaining beech at 4/4 rough x 5x 25 inches. The latter is highly figured and severely cupped. I still need drawer slips in beech, 6-10 of them at 11 inches long. I am going to sleep on this thing tonight and look it over real careful tomorrow. I got enough tiny pieces of beech to make sanding dust to mix with epoxy if I choose to glue and fill.

6. I really don't like having knife marks at the baseline between my tails (or my pins) to deal with after the joints are cut. They aren't so bad on the "not show" side, but I am going to buy a giant pack of blue tape next time I see one to see how far my bifocals and I can go.

471118471119

Derek Cohen
01-06-2022, 3:19 AM
Scott, thank you for the kind words. I am very happy to be plied with beer in Alaska. Just send the plane tickets :)

Now there may be a very simple fix for the dovetails in the first picture ... which look quite good generally. The gap on one side of the baseline is the same as the gap at the top of the socket. This suggests that there is some waste in the corner of the socket pushing the tails away. Go back in and make sure it is clean. A slight undercut, if necessary.

Regards from Perth

Derek

Robert Engel
01-06-2022, 8:10 AM
Check the flatness of wood between tails. Hollow out to the center a little.

I think that’s what’s keeping it held off.

The offset is a little thick.

Ben Ellenberger
01-06-2022, 9:13 AM
Check the flatness of wood between tails. Hollow out to the center a little.

I think that’s what’s keeping it held off.

The offset is a little thick.

Yep, making sure the cuts between the tails don’t have a little hump is always important.

Also you want to make sure that the back walls of the sockets are vertical. It helps if you can stand so you are looking down on them as you pare and you can see the angle of your chisel to make sure it is vertical. The first few half-blinds I ever made had gaps, and that’s what caused them.

Eric Rathhaus
01-06-2022, 2:38 PM
Scott - the gaps I see won't weaken the joint. Any modification is just for the cosmetics. You could always fill the gaps with glue and saw dust or drive in a shim.

Eric

Scott Winners
01-07-2022, 1:08 AM
I put a slight undercut on both the pins and the sockets this morning. I spent about an hour on it, and finally just mixed up some rasping dust with JBWeld, epoxied it up, clamped it square and moved on. I have observed a fair bit of shrinkage in the JBWeld two part epoxy. I am going to give it a couple days to cure, and then probably refill the remaining gaps with west system 105 resin using the 207 Special Clear hardener with more sanding dust. And I might paint over it after that.

The offset is a little thick. I don't have a lot of stock left to cover a blowout, so erred on the side of not screwing up.

Thanks for our inputs.

Andrew Pitonyak
01-09-2022, 9:35 PM
I wish my first half-blind dovetail looked that nice. :D

i agree with the possible issues on the dovetail, given that the spaces seem uniform.

Rob Luter
01-10-2022, 7:43 AM
I think you did well Scott. It sounds like the adjustments you made did the trick. I had the same issues on my first set. With some tweaks they fit fine. I wish I hadn't done my first set in Oak, but like they say, what doesn't kill you makes you strong. I'm working on another small drawer now and lessons learned on the oak box are paying off.

https://live.staticflickr.com/65535/49822777937_85aa6417de_b.jpg