As I wrote previously, I had a relatively easy time surfacing the first side of my big slab but anticipated that it might move with 3/8" of thickness removed and continued drying. Boy was I right. It cupped and twisted significantly. It's really not that surprising because the slab probably had a ton of weight on it as it was air drying for over a year but, with that gone, the slab was free to move. We've had very hot dry weather here so, even with the endgrain covered with paraffin, it's drying fairly fast.
I had turned the heavy slab over to the rough side, so I decided to work on it first and got an unpleasant surprise. The now much dryer slab was decidedly more prone to tearout. Cracks had opened up and these tended to widen with anything but straight on planing. With all of the twists and turns in the grain, especially around the big knots, planing with the grain was impossible. I sharpened my planes very carefully but nothing I tried could avoid deep tearout. Finally I just let it tearout and then used a belt sander for final surfacing. Not very satisfying, but it worked. I was able to avoid all but one dip with the belt sander. The slab is currently 2 3/8" thick so I have removed 3/4" of material!
Douglas-fir is obviously not the ideal species to make a table slab from because it is so soft and prone to tearout. However, this is what we wanted--it is after all the Oregon state tree--so we just have to accept its challenges. I've come to understand that a 37" wide live edge douglas-fir slab with lots of knots in it isn't going to resemble fine furniture and that this is part of its aesthetic. Now that I look at these slabs in pubs and restaurants more closely, I see that they are all that way.
I almost went over to the dark side. Surfacing this slab clearly showed why the standard way is attractive. If you build rails along the sides of the slab and then make a sled for a powered router to ride in across the slab, you can get a flat slab with little or no tearout and not a whole lot of hard work. I didn't do this, but it was at the cost of many hours of hard work and a slab that isn't perfectly flat, although it's close. Once I get this side done, I have to turn the slab over and do the other side again.
This project has turned out to be far more challenging than I thought it would be. Just about everything I thought would work didn't. Looking back, I should have done more research. So, in the interest of saving you from my fate, I am going to go over some things I learned in the next few posts.