That ‘is’ rock solid construction on those sofa frames, doweling with the right kind of glue is just as strong as biscuits, in my opinion, I still find the best doweling jig for me is those dowel points centers, and a brad point bit, your right about the fir wood, I have to start my brad bit a little cautiously when I drill for a dowel hole, because if I go to fast the bit wants to grab some wood fibers and pull itself in another direction, but once I get a good pilot hole started with the brad point , and keep the drill steady the hole pretty much stays spot on, when I drill to dowel walnut boards, the bit stays pretty steady no bit wandering.
The 2×4 lumber does hand plane very nicely, I think fir wood is a step above pine wood, in characteristics of machining.
When I was shaping those legs I was puting a lot of preasure on the sanding drum around the thin ankle part, and the wood there was as solid as needed, if that was pine boards glued up, I think it would have been close to fracturing, the fir wood seems to be stronger.
Well here is this mornings progress, I was able to get a couple hours in this morning before the sun came up over the trees to take away the shade I was working in.
I first put the table in position on the top, the way it will be in final assembly.
Then marked where I wanted to cut it on the perimeter.
I was going to draw some sort of natural edge like on a real slab, but instead, I seen that the outline of the table frame gave a nice freeform edge, so I decided to follow its shape for the top.
I took an over hang for the ends by gauging like this.
and here is what it shows up as.
Instead of a jigsawn keep to the line cut, I decided to use my roto tool to freeform the cutout.
Make it more rough like.
since the bit is not long enough I coped out the rest.
and the resulting cutout.
Using the dark scrap pine boards on the outside underneath edges , gives a nice dark contrast, to the light fir wood in the table topslab itself.
I need to sweeten up the cuts with my sanding drum and grinder, I’ll do that this afternoon when I can get back in the shade again.