Woodworking Talk banner

Sliding Dovetail Breadboards End

13K views 11 replies 7 participants last post by  crosley623 
#1 ·
I am working on a coffee table top that is made up of 5/4 hard maple measuring 24" x 48". I would like to add a breadboards end but in lieu of going the traditional M T joint I was thinking of going with a sliding dovetail across the width just to give it that extra little touch of a visible dovetail. I think the best was to complete the female end on the breadboards is on the router table, but does anyone have any suggestions for how best to cut the male end on the table top piece?

Thanks
Andy
 
#2 ·
Anytime I do something like this, I like to use the same bit on both pieces. That way the angles match up.

But, I think trying to hold a table top on end on a router table will be difficult. but, making a tall fence might help.

You could cut the shoulder for the dovetail on a TS, then use a guide and rabbet plane to finish, or, a dado blade, tilted to the correct angle.

I'm sure someone here will have the best way to cut the male dovetail.

I will be watching this one.
 
#6 ·
Cutting the male portion of the sliding dovetail on the table top is a perfect use for a horizontal router table. That is, if the top is nice and flat. Cutting the female portion on the BB end is a little more difficult since the plough will fill with debris. You can't really remove some of the waste first with a saw or straight bit since the dovetail bit will then grab the work and self feed, losing control. Sliding dovetails need an exact, continuous fit that allows space to get it together. Nothing worse than getting a sliding DT half way and then it gets stuck.

The traditional method of a stopped T&G breadboard end reflects a lot of hard learned knowledge. You have to remember that as humidity changes, the top will either stick out beyond the BB ends or be shy of them, often a fair amount. That DT isn't going to look so good in those situations. Considering this and the difficulty in making a sliding DT that fits well, I think I'd learn from those that have been there, done that and stay with tradition. It will make for a much more solid BB end.
 
#11 ·
Two answers here....

I am in the process of making some TV Trays with bread board ends and I'm using the stopped mortise technique.

As for the sliding dove tail. Cut the mortise first on your router table. Hog out the majority of the material first with a straight bit before using the dove tail bit. Use a feather board(s) to keep the stock against the fence.

For the tenon part I would use the table saw and a dado blade. The fence controls the length of the tail. The angle of the dado controls the alignment of pin to tail. The height of the blade controls the fit of the sliding dove tail. Multiple passes can be used to sneak up on the fit. (If you saw is Left Tilt, you may need to put the fence on the left side of the blade.)

If you don't have one, this may be a good time to purchase an angle box.


There is one more consideration. The bread board end is intended to keep the top from warping however, room must be allowed for wood movement. (I'm sure that you knew that.) The traditional method of bread board ends is to glue the center and then pin the bread board end to the top. With a sliding dove tail it is going to be impossible to glue the center only and pins are certainly going to be required.
 
#8 · (Edited)
I would go with a stopped T&G, that way anything that gets exposed either way will be a square edge. You can allow plenty of movement room on the ends without it showing. Drill your pins, remove the BB end and elongate all but the center one or two holes, 1/4" each way. With a T&G you can make a deeper groove and tenon than you can with most dovetail bits, which will add great stability for the BB ends from tipping down. The tongue/tenon can fit tight in thickness. After all, you can't make that sliding dovetail tight or you'll never get it together unless you taper it, absolutely perfectly. Absolutely perfect and woodworking don't often go together so I avoid that challenge, there's no money in it, just heartache. Which is where I think you are headed with a sliding DT BB end.
 
#9 ·
I appreciate the info, i will go with the T&G roughly 3/8" thick by 1-1/2" deep. I will be sure to post some pics when finished.

One more question, when you drill for the pegs do you normally drill through both sides and peg the top or just from the bottom and through the tongue.
 
#10 ·
You can do the pegs either way depending on whether you want them to show. Square, contrasting color pegs can be interesting and hint at the joinery used. There can be seasonal changes in thickness and the pegs may stand a little proud of the surface. When I said elongate the holes, I meant on the tenon only, not the BB end.
 
#12 ·
Well I spent all day yesterday routing out the mortise on the bb end and cutting the tenons on the top. I ended up going with 3 tenons that are 4" x 2" with a 1" continuous stopped tenon. I made a jig to route the mortise and a jig to route out all of the waste for the tenons. The only problem that I ran into was that my router bit is not long enough to route out the 2" deep mortised for the actual tenons so I had to resort to the old drill and forstner bit.
Now all I have left is paring away the tenons for a good fit and drilling out for some square pegs, I have a few chunks of zebra wood that may look cool.

Thanks again for all of the info and I will be sure to post some pics when complete.
 
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top