How to cut a tapered sliding dovetail joint

[@TheSMEAC]

I don’t have the tools you do and admittedly would have to do nearly all the fine fitting with the side rabbet planes after saw and router work, but even by hand, the process of building out the taper on the batten and in the top would generally follow the same thought path. Anyone can make a taper sliding dovetail that tightens in the last inch; what far more tedious is having the entire batten come into battery within the slot right at the culminating point of final extension. You rock brother! 🫡

[@jaem-xz7dw]

Thanks for sharing the detailed steps. I have seen Ishitani’s video many times but he didn’t go in detail other than a showing a jig. Loved your trestle table build video.

[@briantheprion]

Thank you Jae! His videos are awesome and I find really relaxing to watch but I found it sometimes hard to follow what he was doing since he’s so good!

[@jimrosson6702]

Great video

[@briantheprion]

Thank you Jim! I hope it helps in your current or future projects!

[@regisfourcade7145]

Franchement c'est une super vidéo comme il y en a peu : les images sont très claires sur les points importants et le calcul et les tracés sont d'une limpidité exemplaires . Tu mérites aussi d'avoir aussi des millions de vues !

[@briantheprion]

Merci pour vos aimables paroles. Je voulais montrer mon processus car je n'ai trouvé aucune technique sur KZbin, alors j'espère que vous l'avez trouvée utile ! Thank you for your kind words. I wanted to show my process since I couldn’t find any technique on KZbin so I hope you found it helpful!

[@craigmeaney]

thank you Brian, great video

[@briantheprion]

Thank you Craig!

[@BubbaLeroy]

Very detailed instructions! What is the purpose of the slight taper vs. a straight sliding dovetail joint?

[@briantheprion]

Great question: straight non tapered sliding dovetails are usually used for short segments such as on shelves or bookcases (usually under 10 inches). The problem once you go beyond that is the friction is so great, the parts seize when you try and go to fit them together. This is overcome by introducing a taper. Thanks for watching and commenting!

[@dannogoo]

That's brilliant problem solving. Thanks for the detailed explanation.

[@briantheprion]

Thanks Dang for watching and commenting!

[@kinder-works]

That came out soooooo clean!!! Great job man!! Now I have to go do that 8 times to attach the dividers and shelves for a floating Media Console I’m building for a client out of a matched set of Tiger Maple!! Keep it up man!!

[@briantheprion]

Thank you so much! Keep me updated on the progress!

[@wolframherzog636]

Well explained. thank you

[@briantheprion]

Thanks for watching! What are you building?

[@wolframherzog636]

@ I am in the design process for a little settop workbench

[@briantheprion]

@wolframherzog636 awesome let me know how it goes!

[@crazycdn8327]

You need to make more videos!

[@briantheprion]

Thank you for watching and I definitely will!

[@brettevans3444]

Thank you so much for this! I had a few questions as I've run into a few issues. How much material do you remove on the tapered side for the batten? The lighting at the router table I couldn't see but it looks like you had two marks on the on the tapered side of the batten. I'm guessing the batten marks mirror the infeed of the dovetail dimensions on the table and you move the fence to get close to the outer marks on the batten but not cutting through it. Then the taper jig will automatically cut the proper width of the dovetail on the narrow side. Then how it gets snug is by creeping up on the straight dovetail side on the batten? I think I've answered my own question but just wanted to make sure.

[@briantheprion]

On the tapered side of the batten, once you made that tapered pass, any material you remove to get it to seat should be on the non tapered side since it’s easier to control. In my case my batten had bowed a little bit and so the tape marks the area that was poochy/convex a bit and I was just trying to shave the hump off (I hope that makes sense) ordinarily if you mail your stock and perform this procedure right away, there shouldn’t be any Boeing and the scenario I’m showing is a special circumstance. But you got it: you creep up on the fit on the non tapered side 👌

[@ptrvideo]

Elegant Brian, masterfully done!

[@briantheprion]

Thank you kindly!

[@billcarnell4588]

I would like to see how you sharpen plane irons?

[@briantheprion]

Hi! I might do a video on that in the future but my method is almost exactly how Deneb Puchalski does it on the Lie Nielsen series on sharpening. I do not however use the “ruler trick” on my plane irons. I just do it old school and polish the last inch all the way up to a 16000 shapton. It’s a one in a plane blade lifetime and then I never have to fiddle with finding the ruler and holding it still while sharpening. Also if you put a camber on the blade, it’s easier to get the wire edge off the back with a flat back blade. I hope that makes sense. But yeah I’ll def put a video up in the future if more are interested!

[@mattelias721]

This is a good explainer. However, were you finding the bind zone using feel, sound or both? I personally couldn't hear any differences, but my hearing is shot.

[@briantheprion]

Thanks Matt. I should have clarified in my video that the tapping method in the video is a special case scenario because the batten I had used had developed a bit of a bow in the side to side direction. So it still sits flush and flat on the table but the side to side movement caused me to see where it was binding. Its also a good idea to kind of tap the joint to see if indeed it is binding in one particular section vs the entire length and yes, its a feel thing since the hammer bounces a bit more here as well as sounding different too. Does that make sense? In theory if the piece was straight, all i would have to do to make it seat home is just run the non-taper side against the router fence thus taking a tiny shaving off that side and it would then allow it to slide home. Its confusing no doubt what I wrote but I hope that clarifies things a bit. Cheers Matt!

[@mattelias721]

@@briantheprion That clarifies it perfectly!

[@duster8100]

A very well done video. Where did you get the magnetic dial indicator holder from?

[@briantheprion]

Thanks Duster! It’s made by Mag-Jig

[@dannielrolfe8079]

Thanks for the great video. I’m planning a table build and was not sure how to tacked the tapered dovetail. Quick question, what brass tool did you use to clean up the dovetail?

[@briantheprion]

You’re welcome! I couldn’t find a good video when I was tackling this project so I made this in hopes it would be useful to someone. The tool used to clean up the dovetail is called a side rabbet plane. Stanley made the 98/99 left and right version originally and the one I’m using is made by Lie Nielsen. Hope it helps man!

[@dannielrolfe8079]

@@briantheprion thank you. It’s very helpful. You are very talented.

[@briantheprion]

@@dannielrolfe8079 thank you Danniel that’s kind of you to say. Good luck on the project dude!

[@rolandgdean]

I once had a Woodcraft employee tell me to take my calipers and get them out of my wood shop because operating with that precision was pointless in woodworking...I stopped talking to that guy...lol. I go with the old adage of, "Worry about your pennies and your dollars will take care of themselves." So, I am very detail focused like you seem to be, and YES the material will "move" but the closer you can get to perfection, the better things will be in the end.

[@briantheprion]

Oh man yeah I occasionally run into the “this is woodworking and we’re not machinist” but I’m with you 100% about the pennies adding up for sure! I really think it’s what makes the stuff you make stand out!

[@rolandgdean]

Thanks @@briantheprion , I agree.

[@markchaisson9140]

I always assumed the tapering dovetail cut Ishitani did was built into the jig, but this makes sense.

[@briantheprion]

I believe you're right. The taper he produces when cutting the mortise is set by a wedge you later see him use that he sandwiches on the batten when he cuts the tenon side when it rides against the router fence. The condition to this is that the router sled has to be dead-nuts accurate 90 degrees for the wedge to work double duty if that makes sense. For me at least, I felt it was easier to cut the tapered mortise and measure what the actual reality measurements are and then produce a wedge that can be really fine tuned alone and once I was happy with it, then use it to generate the tenon. Not saying my way is better. It just worked better for me to produce a consistent joint in my hands.

[@mchaisso]

@@briantheprion Rewatched the Ishitani video and now see the reused wedge (wasn't sure where it was built in before). I guess the benefit is the taper should be exactly replicated with his approach. Or at least in theory. Looking forward to more "Ishitani, explained" content, and other projects you produce. Actually I had assumed the batten was tapered a tiny amount and the mortise straight, so that it would be snug on one end when hammered in. Your previous comment about friction makes sense. Very lucky I saw this since I'm about to make a trestle table this summer and this avoided a huge error.

[@briantheprion]

I’m glad you stumbled upon this video to help out on a project you got going on! The algorithm works sometimes lol. Cheers man and let me know how it goes!

[@trevorhayes3204]

@@briantheprion About your comment regarding the wedge working double duty - Are you suggesting that the router sled walls (without the wedge) need to be perfectly parallel in order for the wedge to be accurate in both applications? Just trying to make sure I’m interpreting your concerns here correctly

[@craigmeaney]

Brian, which whiteside bit did you use? I am building a cherry trestle table and would like to use this joint.

[@briantheprion]

HI Craig, great eye. How'd you know I used a Whiteside bit? its Part # D14-75 (14 degree 1/2 inch shank, 3/4 cutting length, 3/4 cutting diameter, 3 inch overall length bit). Best of luck my friend and let me know how it goes!

[@craigmeaney]

@@briantheprion thanks Brian, you mentioned which bit you used in the description for your trestle table video :) I will let you know! I have a bookmatched slab for the top, fingers crossed I don’t screw it up!

[@briantheprion]

Oh man you got this! Ain’t no way you gonna screw up! Just make your layout markings precise and then just tackle each part bit by bit. You got dis!

[@claytonmitchell03]

I rarely comment on videos but your work is amazing! Are you self taught? Either way you deserve far more subscribers and credit for your work!

[@briantheprion]

Thank you so much for watching Clayton and your kind words! Yes self taught in the sense I read about it or watch on finewoodworking and add my own way of doing things. This tapered method other people have obviously done but there are no clear instructions on doing it for this scale on finewoodworking...at least that I can see. Mr. Ishitani is where I was first introduced to this joint but I did it slightly different than him. Im getting the hang of spindle turning especially with the skew but havent started face grain turning yet. Where did you learn how to turn? You produce clean work too. I really like segmented bowl video!

[@claytonmitchell03]

@@briantheprion Hey thank you! I definitely have a lot to learn when it comes to furniture making but strive to be as good as you one day! As far as woodturning it sounds like we took similar paths, I consumed as many videos and books as I could and then lots of trial and error! Segmented turning is so fun because you can really create your shape before it even hits the lathe and it opens so many more opportunities vs greenwood turning. I should do more filming to post on youtube but I hate the editing part... Thank you for your response!

[@briantheprion]

Yeah us tinkerers just kinda figure it out as we go along through trial and error and I think that’s a really valuable skill to have…the mcgyver-ability!