Why do you have to remove so much material? A slab like this will almost inevitably twist and cup. Across its width you have vertical grain changing to flat sawn and back to vertical grain. It basically has to cup. The wild grain pattern associated with the huge knots almost guarantees that the slab will be "wonky." That is its beauty. During the course of this project I came to understand that there is an entirely different aesthetic at work here. The cracks and knots are part of the tree's story.
I elected to use Arm-R-Seal to finish the slab, brushing it on the bark and using a cloth on the top. I didn't want the "plasticky" look that you often see, the result of a thick hard finish. Here is the result:
I am very pleased with the result. It is unique and has character. This is about as rustic as you can get short of just using the rough sawn slab as is. It's certainly not for everyone. Welcoming cracks, pitch pockets and knots is kinda weird I admit.
I got the ultimate compliment from the cable guy as I was applying the finish. He admired it and said, "It looks like it belongs in a brewpub." As it happens, I am a big fan of brewpubs and knew exactly what he meant. Douglas-fir is our state tree, it played a central role in our history, it is fundamental to the beauty of our landscape and we like to keep it close. Same with draft beer. You can travel the world but you won't find a beer better than an Oregon IPA made with our own Cascade hops. This table is going to see a lot of it.