Design question. Miter or dovetails..

Re: Design question. Miter or dovetails..

Derek Cohen (in Perth, Australia)

Virgil, I could argue for mitred dovetails, which provides both the look and strength, but the answer may lie with what looks better to you. A butt-jointed mitre is cleaner but needs help in remaining tight. Biscuits help here. Dovetails do not come apart.

Regards from Perth

Derek

Re: Design question. Miter or dovetails..

Virgil Johnson

If I do the miter it will have segmented splines since the base is 9" (228.6mm) wide. While I was raking the leaves (something a Shaker probably did not do)earlier I was thinking a miter was more difficult back in the day when it would have had to have been sawed "spot on" without the aid of a miter gage and the luxury of a table saw equipped with crosscut blade. The guy simply banged out his umpteenth dovetail joint after the morning prayers and milking.

Re: Design question. Miter or dovetails..

Bill Tindall, E.Tn.

The problem with a dovetail down there is that it will attract attention to a place that doesn't deserve attention. In much Period furniture this joint is mitered.

Re: Design question. Miter or dovetails..

Don Stephan

It is possible the Shakers would have had 45 degree shooting boards.

Re: Design question. Miter or dovetails..

Virgil Johnson

Good point and taken to heart. I cut the miter about 30 minutes ago. I like the way it looks.

Re: Design question. Miter or dovetails..

Bruce, a MN Galoot

There’s still time to put a spline in that miter and make an extremely strong joint.

Re: Design question. Miter or dovetails..

Virgil Johnson

The spline is a project for next week. I was thinking of biscuits but my old Freud plate jointer is not up to the task. It was never a top shelf tool for regular biscuits slots but for this joint it is totally worthless.

Re: Design question. Miter or dovetails..

Yonak

Virgil, could you put blocks behind instead of messing with splines or biscuits ? It's only a base, right ? You'll be attaching it to the top ?

To add to Yonak's suggestion...

David Yoho

I've done several of these types of bases before where the corners were mitered. To reinforce the corners I have applied "blocks" to the inside as high up as the point where the case will sit down inside the base. These glue blocks can be simple square ones, triangular strips, or several triangular blocks that are glued and tacked.

I took this idea from all the old furniture I worked on. It worked for the old guys so it should still be good enough today.

There is room for blocks.

Virgil Johnson

Just for overkill I was thinking of both a segmented spline and 2-3 glue blocks on the inside. The spline will help for alignment if its cut accurately.

Re: There is room for blocks.

Barry Irby

I have made several blanket chests and toy boxes with similar feet. Also repaired a few. My solution is to make a leg inside the corner that supports the chest and the bracket feet are purely decorative and only hide the legs. That way the legs are vertical grain and take the load and the bracket feet don't quite touch the floor and don't get broken when the chest slides around. Vertically, its a cross grain connection so allow for movement.

Corner blocks details

Bill Tindall, E.Tn.

As I mentioned earlier corner blocking a mitered base frame is a common feature of Period furniture. In these cases the case sits on these corner block posts which extend a small amount below the frame.

The potential problem is a cross grain joint of post to base. Once way around this deficiency is to build the post from alternating grain orientation layers, 3/4", or thereabouts.

Size the mitre joint before glue up.

Derek Cohen (in Perth, Australia)

Hi Virgil

One strategy is to size the mitre joint before glue up. To size the joint, mix your white or yellow glue 50/50 with water, and then wet the end grain. Leave this to almost dry, then spread your full-strength glue and clamp together. The sizing seals the end grain, and the joint will not be glue starved - which is generally why end grain glue-ups fail.

Biscuits would help reinforce but are not needed if you then add corner blocks.

Regards from Perth

Derek

Second this

David Yoho

I learned this idea years ago for gluing end grain joints and it works well.

+2 On Corner Blocks

Ron in Sterling, CT

I have made a half a dozen blanket chests for children and grand children. They all contained corner blocks. They make the mitered corner joints rock solid with no splines. As Bill says it is important to alternate grain direction for control of stock movement. Good Luck.

Ron

Re: Second this

virgil johnson

Likely I'll use Old Brown Glue simply because I like the open time. I'm experienced with sizing with yellow glue. How about OBG.? . any tips with liquid hide glue sizing?

Re: Second this

David Yoho

Most of the time I've done this it's been with liquid hide glue. Great thing about LHG is should something happen after the initial coat that distracts your attention too long and it dries, the next application will instantly bond to it.

No real tips to pass along on this. The "sizing" application doesn't really need to be thinned but you can if you want. What I've always done is apply the hide glue to both surfaces and rub it in with my finger leaving behind a thin layer on the surface. Let it dry and then apply the hide glue like normal before clamping. Add the corner blocks and you're good to go.

dovetails would have been tirival in original

Bill Tindall, E.Tn.

For those that have not become proficient at making hand cut dovetails this joint might appear difficult. It's not. For someone that makes them regularly a dovetail joint joining two pieces at right angles is trivial and functional. Even I dovetail the back bracket foot with a half blind in this kind of base construction because it is easier than a miter. With look removed from consideration dovetailing the base described is both strongest and easiest to execute.

Two means of case construction with a base

Bill Tindall, E.Tn.

In Period case pieces I see two options. A box is dovetailed together and this box (containing drawers and or doors) sits on a base as you have shown. The base is typically mitered and corner blocked. This construction is superior because there are no cross grain issues among case, base and applied moldings. And, the dovetailed box keeps the case sides flat which enables tight fitting drawers.

A second option is to run the side of the case to the floor with a cut out for what ever profile there might be on the side. The base molding is then applied to the bottom of the case using care to not constrain the seasonal movement of the case side by the cross grain molding. There are less steps involved in this construction and it can work well if done with care. I have used it on several case pieces.

Re: dovetails would have been tirival in original

Yonak

Bill, your third sentence : "For someone that makes them regularly ...." is all-telling.

Miter cut and glued.

Virgil Johnson

Earlier I mentioned I decided to miter the joint and here is the outcome. Not too difficult to cut the joint but clamping was a pain during glue up. I can see the advantage of using dovetails over a miter. Dry clamping was a breeze since there was no glue to act as a lubricant and make the parts slide. I sized the joints first and a bit later applied a second coat of glue and proceeded to clamp. Even though I heated the glue it gelled before I could get the clamps on and would not compress easily making a slight gap in the joint. Possibly I used too much glue. I did not panic since I knew that hide glue bonds to itself so I disassembled the parts scraped off the glue that was not set. I waited till my wife got home and she helped with the second attempt.

I sanded the area behind the base and applied some finish behind the joint so the glue would not stick and I would be able to remove the base for finishing.

Re: Design question. Miter or dovetails..

Philip F Duffy

In my amature/novice level I often use a saw-cut or 2 thru the dovetail joint and find it reinforces. It that must my imagination? Or useful? In my case it seems to be a happy alternative to dovetails. Philip

Question

Bill Tindall, E.Tn.

would be able to remove the base for finishing.

Unsure how you are building this case that would involve removing the base for finishing. This approach likely made assembling this joint more of a challenge than would typically be the case. Typically one section of this miter is either permanently fastened to the case, or to a base that the case will then set on with a molding applied to make the transition.

The mitered pieces get installed one at time, always butting against the mating piece fixed in place. The first section, typically a side, gets butted against the front piece which held in place by clamps. When the fit is good it gets permanently fastened to the case side or frame side. Then the front is installed, butted against the side that is now permanently fastened to the side. Finally the last side is fitted and fastened on.

Doing these joints on at a time enables adjustments to the fit to get it perfect before permanently fastening.

If you fitted this base piece to the case with out any of it permanently fastened to the case I'm impressed you got the fit you wound up with.But it was a difficult means to an end.