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Forum topic by bhacksaw posted 05-27-2015 10:06 PM 841 views 0 times favorited 6 replies Add to Favorites Watch
View bhacksaw's profile


163 posts in 1821 days

05-27-2015 10:06 PM

I have my 20 year high school reunion coming up this summer. I was contacted by the reunion committee to see if I wanted to build a bench that my class could donate to the school to be put in the outdoor courtyard where the seniors get to eat lunch. My design was picked as the best (they had to solicit other designs out of fairness) and the budget was approved. I was all set to start building when I got the news that the principal said that the bench design would have to be submitted to the county’s building code office for approval, which could take months. Sooo, no bench. But it’s not a complete wash. I got some design experience (this is only the second original design I’ve created). I’ll save the design and build it someday when I have a yard.

Now, onto the advice. I went with through wedged mortise and tenons for the legs and the lower stretcher, but I figured I would use dowels on the top stretcher because I was worried about having a mortise too close to the edge of the leg. Is this a viable design or should I use through wedges on them, too? Also, I’m thinking that the upper stretchers would NOT have to be glued or otherwise secured to the top seat piece. Is that right?

6 replies so far

View mahdee's profile


3883 posts in 1764 days

#1 posted 05-28-2015 01:17 AM

I would secure the top stretches (aprons) to the bench top using a L shape or figure 8 fasteners. You can make your own wooden L shape ones. Definitely, no dowels for them. A nice tightly fit tongue and groove with provide excellent stability to it. Center stretcher can be eliminated, but it looks good.


View AandCstyle's profile


3052 posts in 2253 days

#2 posted 05-28-2015 01:28 AM

bhacksaw, that is a very elegant piece you have designed and you should be proud of it. I would do the wedged tenons through out just for uniformity’s sake, but that is just my aesthetic. Another option would be to hide the dowels under plugs cut to match the leg grain.

Another consideration will be the selection of a wood to use outdoors. My preference is white oak, but cypress, black locust or cedar will be good options. FWIW

-- Art

View jerryminer's profile


923 posts in 1438 days

#3 posted 05-28-2015 02:10 AM

I keep looking at that top and wondering what will keep it from cupping. Instead of a single mortise in the center, I think I’d be inclined to put a pair of mortises right at the outside edge of the leg.

And I would use M&T, not dowels, on the stretchers.

And I would attach the stretchers to the top.

Does look nice, though

-- Jerry, making sawdust professionally since 1976

View Ghidrah's profile


667 posts in 1219 days

#4 posted 05-28-2015 02:56 AM

I’d keep that design for myself, teens are animals they’ll be all over it like drug crazed baboons. If it survives for any length of time and it ain’t fixed to the ground it’ll probably be stolen. Think heavy duty rustic

-- I meant to do that!

View HazyDavy's profile


20 posts in 1502 days

#5 posted 05-28-2015 03:08 AM

Agreed—it’ll be vandalized and is too nice for that.

View bhacksaw's profile


163 posts in 1821 days

#6 posted 05-28-2015 08:42 PM

Thanks for the responses and the concern for teenage debauchery. I supposed I would have quadruple poly’ed it if it had been installed at the high school.

I’m still wondering about the aprons. I was thinking that if the grain of the top is going the length of the bench, movement would be from front to back and therefore it would be best not to anchor the aprons to it, allowing the movement the freedom it needs. I looked up figure 8 fasteners, but they aren’t meant for pieces that run parallel with the grain.

Also, for the suggestions against using dowel, is it because they would form too weak a joint? Do you think having a 1×4 mortise so close to the sides of the leg pieces is OK?

And finally (for now) I was going to go with African Mahogany for the wood because it has decent rot resistance and doesn’t seem to be too tasty to bugs. Also apparently keeps its color well in sunlight. Are these assumptions (totally untested be me) true?

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