What's the price NPC's will give you for this? Some smithing guides have this listed as a synth to do after nodowa, but i'm thinking that the sell back price can't be any higher than 10k, at which price you would suffer horrible loss based on 20-40k darksteel ingots.
Though I'm not totally sure whether this actually stops giving skill+ in woodworking when at 8, which it very well may, I CAN say that if you're intending to make these, lv. 8 woodworking is NOT sufficient.
I only began to truly get consistent results (as in, very few failures) once my woodworking was around 34. So, to sum it up... though the cap might be (might, i'm not sure) only lv. 8 wood, if you're intending to specifically not fail 90% of your attempts at synthing this, get it up to somewhere between 30 and 34.