Prepping/finishing Redwood Slide

[shutton]

I've been charged with finishing a slice of a redwood log that's initially going to be used as a wedding cake platter, then turned into a small nook table. I have a few challenges, some of which I'm working through, and some on which I'd appreciate some advice.

First off, flattening went fairly well with the belt sander. It's very close, and if I end up using Envirotex for finish, it won't matter.

Crack filling also went quite well. Two applications of 30-minute epoxy did a nice job (some of the cracks were so deep that the epoxy didn't fully settle until it was almost set up). That said, I wish I had "fenced off" the areas the first time, since the epoxy penetrated a bit causing darkening. Just took some extra sanding.

Now, for the challenges I haven't tackled yet:

1. Dark spots in the sapwood. I applied some mineral spirits to get an idea of how it was going to look. Of course, the sap wood soaked it in *fast* (much faster than the heartwood), but also revealed that there are a few unsightly dark patches in the light sap wood (it just looks *dirty*). They don't sand off, and I'm deathly afraid they'll reappear when I apply the finish. Anyone know what they are, and if there's something I can pre-treat them with to prevent them from appearing when "wet" with the finish?
   
2. Live edge. It's fuzzy and flakey. Fortunately, if the mineral spirits and epoxy are a good indicator, the cut edge will seal well (albiet, quite dark). But the sides are another story. If I spray it with thin polyurethane (and I might even splurge on a HVLP sprayer for this), will it soak up the finish and "polymerize" well? Will it backfire? How can I stabilize it?
   
3. The slice isn't perfect. it's about 1/2" thicker on one side. This isn't a problem while it's playing its role as a cake platter (we'll just shim it), but will be annoying when it assumes it's table form. I could just flatten the other side and build a mount with the complementary angle, but I'd rather make the piece perfectly even in thickness. I have some ideas on how to do this, possibly starting off with a power hand planer to pare off the high edge, then flatten it las I did the other side, but I'm open to ideas.
   
4. What did I forget to ask about that's going to cause a, "doh!" moment?
   

-Scott

[AMarshall]

Hey Scott, I just noticed your post from the other day. FYI, you may have gotten more answers by posting in the "Finishing" forum.

Here are my thoughts, though I am certainly not an expert finisher! Ha. I'm assuming you are simply going for a clear finish, not staining the piece.

1. The spots you are talking about are likely blotchiness in the redwood. I haven't worked with redwood before, but I can imagine it's similar to other softwoods like cedar or pine. With all off these, it's a good idea to put on a sealer to prevent blotchiness. The traditional sealer is shellac, but folks have been getting great results with Charles Neil's new Pre-Color Conditioner. Look at this post on The Wood Whisperer site for more info: http://thewoodwhisperer.com/blotch-control-to-rule-them-all/

2. I have had good luck using shellac to stabilize old flaking paint, and this could work well to stabilize the live edge on your slab. I recently was asked to use a reclaimed door to make a piece of furniture for a friend, and every time you would even breathe on the door paint would flake off in large chunks. I put some shellac in a spray bottle (like a windex bottle) and soaked the door until the shellac was dripping off. No finesse involved in that one. The shellac got behind the paint and acted as a glue to reattach it to the wood of the door. I bet this same process could work on your live edge, but of course you should test it first.

Good luck with the rest of the project! Post some pictures if you can.

Aaron

[AMarshall]

Whoops! I forgot #3 and #4.

3. I would likely leave it alone and adjust the base, but if you truly want it evenly thick you may want to think about a router sled. Folks use these to flatten their workbench top all the time. Basically two long parallel beams on each side of the slab, then put a router on a shuttle that spans the two beams. It will take a while, but it will get you there.

4. I have no idea where your "doh!" moment will come from, too bad. Is the slab fully dry? My biggest worry would be that the slab cracks due to drying stresses.

Aaron

[shutton]

Whoops! I forgot #3 and #4.

3. I would likely leave it alone and adjust the base, but if you truly want it evenly thick you may want to think about a router sled. Folks use these to flatten their workbench top all the time. Basically two long parallel beams on each side of the slab, then put a router on a shuttle that spans the two beams. It will take a while, but it will get you there.

4. I have no idea where your "doh!" moment will come from, too bad. Is the slab fully dry? My biggest worry would be that the slab cracks due to drying stresses.

Aaron

You made my day with the router sled idea -- I never considered that. I'll poke around for some design ideas. As it is, I didn't do as good of a job flattening the top as I'd hoped, so I might end up doing something like that when it comes back to me to be turned into a table.

-Scott