Managed to get all four sections of the top glued up. A bit laborious, but pretty straightforward. Decided to take a suggestion and use some jatoba for contrast.
The plan was to glue up 4 sections of boards. Then I’d flatten each section before gluing the sections together. The rationale was that it would be easier to flatten each section using the powered jointer and planer than it would be the entire top using hand planes.
There were two problems with this approach, both of which I found after the fact. The first problem is that the glued-up sections are heavy and unwieldy. Particularly so for a guy recovering from a fracture in the wrist.
I’m out of the cast now, but the wrist will take some time to fully recover. I discussed physical therapy options with the doc, but when he found out that I build furniture and play guitar, he figured I would get all the therapy I needed.
The second problem is that there is a small but inevitable amount of sag in a board suspended between two points. Even if the board is 2” thick, it will sag under its own weight even before adding the weight of the clamps.
So after glueing the sections, I had four pieces that were all less than flat and had a bow. I was able to run them through the planer to get them mostly flat, but my efforts with the jointer – even using a roller stand to support the infeed – were insufficient to remove the bow. The pieces had about 1/16” gap at the ends. I was committed to a particular board orientation, too, no way I could just flip a section around to have the bows coincide.
On a hunch, I checked with the Sagulator. I calculated that for a 2” thick cherry shelf 4.25 inches wide and supporting 50 lbs of clamps with supports 6’ apart will result in a sag of 0.06”. Oddly, this is almost exactly the amount of bow I had to contend with.
So I took the jointer to the boards. My interpretation of heft and hubris is a 24” long beech & ipe locomotive:
I continued to use the sawhorses I started with. They were fine for glueing up a small number of boards, but really unsuited for being worked on.
Started being a big shaky gluing together two sections:
And very close to dangerous while working on fitting the third section:
Not to mention a really high and uncomfortable planing height. But the shavings were rather long and pretty:
When I nearly tipped the whole thing over, I decided to make a better way to support the slab. Using scrap 1×4s and 2×4s, I built a pair of these:
Adjustable by changing the location of the horizontal piece between the two uprights. Easy peasy. Other than hauling the slab off the sawhorses and onto their new supports.
Finally got the third section fitted and glued:
Adjusted the support height and fitted and glued up the fourth:
Next step is the dog strip
-- Mark Kornell, Kornell Wood Design