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By custard
#1185752
Sheffield Tony wrote:is the splay of the legs small enough that you don't have to worry about the compound angle


Basically yes.

The straight through tapered leg adds to the visual impression of the angle, it looks more "dynamic" than it actually is.

Regarding the joinery, just leave a decent shoulder at the bottom of the apron tenons (say 12mm) and that'll soak up any issues. It's easiest to just treat each side as a separate component, then there are angles but not compound angles. When it's assembled the entire top line needs flushing down so it mates with the top, that's the only time you're really aware of compound angles.

Projects like this are good practise before getting into the seriously compound angles you deal with on things like complex jointed chairs. It's joinery like this that, as my daughter would say, really twists your melon!

Pear-Chair-1.jpg


Pear-Chair-2.jpg
User avatar
By nabs
#1185995
Thanks again for providing the extra information - I thought I had understood, but then I was a bit confused by this comment:

custard wrote:Regarding the joinery, just leave a decent shoulder at the bottom of the apron tenons (say 12mm)


... anyhow, I have tried to draw the joints - is this how it works?


Image

Image


Image
User avatar
By custard
#1186036
nabs wrote:I have tried to draw the joints - is this how it works?


Yes, that is how it works, with a finer leg (say 32mm or less) you can effectively merge the tenon into the haunch and turn the mortice into a "stopped groove", which then makes it a doddle to produce on the router table.

I envy your SU skills by the way, how long did it take you to become that proficient ?
User avatar
By nabs
#1186047
I used it to design my shed/workshop which meant I used it for hours and hours - I had never used any 3d design software before, so possibly they all work in similar ways, but I found it quite unintuitive at the start.

Once I got to grips with the basics then it was quick to pick up the rest (actually there is quite a limited set of tools to learn - and the way they work will be familiar from real world tools, it is just getting used to how to manipulate them efficiently on the computer that is the tricky bit, IMO)
User avatar
By nabs
#1186324
a quick question Custard - if you were doing the joints with hand tools, would you angle the tenon to take account of the splay in the legs, or keep the tenon square and angle the mortice? Or does it make no difference either way?!?
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By custard
#1186329
On this project it makes little practical difference, incidentally that's why I recommend a 12mm plus shoulder at the bottom of the tenon, it's to give you some wiggle room for exactly this issue.

If the splay angle is greater (common with chairs for example) then you get into the problem of short grain weakening the tenon, the normal solution to that is a mortice that's plumb to the mating faces on both sides of the joint allied to a loose tenon.
User avatar
By custard
#1186387
nabs wrote:thanks - I am probably being thick, but why does the 12mm shoulder at the bottom of the tenon help?


One way this can go wrong is if the mortice (or even a dubbed over lip of the mortice) is peaking out from below the apron rail, with angled joinery it's quite easy for that to happen. You might decide to make the bottom edge of the apron co-planar with the top which will trim off a few mill from the inside edge of the apron rail. Or if there's a curve on the bottom edge of the apron rail, in real life that curve can creep back a whisker, which might then expose the mortice. On a rectilinear design you'd normally have a shoulder that's about 6mm, on an angled design make it 12mm and you're bomb proof.