Finally got the main stringer set for the new stairs — a few observations

I remember doing a 4x10 mono-stringer last year and we needed three guys just to get it on the brackets. Getting those 4-inch thick white oak treads leveled was the biggest headache. If you haven't started drilling for the balusters yet, I'd suggest making a custom jig. I ruined one of my $120 treads becuase the bit wandered on the end grain, and I still regret not being more careful with the drill press setup.

That floating landing setup is a smart way to keep the window clear. I did somthing similar with a concealed header in the wall framing for a 48-inch square landing. One thing I learned the hard way was checking the deflection after the drywall was up. Even with the steel bolted in, the weight of a person hitting that turn can cause a tiny bit of vibration if the wall studs aren't doubled up or blocked properly. I ended up adding some extra L-brackets from Grainger behind the finish work just to stiffen it up before the final paint.

That hovering landing looks incredible, but I learned the hard way about deflection on a similar build. We went with a 12-inch wide C-channel hidden behind the drywall to catch that landing becuase the bounce was driving my kids crazy every time they ran down the steps. Even with the bolts tightened down, that lateral movement can be a real pain if the wall framing isn't reinforced with extra blocking or some heavy-duty Simpson hardware.

For the treads, I actually skipped the traditional balusters. I went with a side-mounted glass standoff system because I didn't want to risk drilling into the top of the wood after all that work. If you're using something like a 3.5-inch thick ash or walnut, that grain is brutal on bits. I ended up using a Festool drill with a depth stop to keep everythign consistent on the handrail side, but it was still a nerve-wracking afternoon. Just make sure you've got a sharp Forstner bit if you do stick with the vertical balusters; those standard twist bits heat up way too fast on thick stock and can leave nasty scorch marks.

Make sure you used at least 3/4-inch A325 structural bolts on that stringer bracket. I hit mine with a Milwaukee 2867-20 high torque to ensure zero slip before the drywall went up. Since you're about to drill those treads, skip the cheap bits and get a WoodOwl Ultra Smooth 5/8-inch auger. It clears chips way better than a Forstner when you're punching trough 4 inches of oak, and it won't overheat. Are you going with a flat bar rail or cable? If it's cable, I'd suggest the Feeney 1/8-inch kits. They’re alot easier to tension than the generic stuff, and the stainless finish holds up way better against hand oils over time.

Looks solid, but all this steel and bolt-on work makes me miss the days of a proper housed stringer. Back when we didn't have fancy jigs, we’d spend a week just hand-chopping the mortises into a 2x12 with a sharp slick and a mallet. No vibration issues when your treads are wedged and glued into the timber itself. Just a thought on those balusters: if you're drilling into that end grain, rub a little candle wax on the bit. It stops the heat from burning the oak and keeps the bit from binding up. Are you planning to finish those handrails with a oil-rub or poly? I always preferred a hand-rubbed linseed oil myself.

Quick update — I took the advice and made a custom jig for the treads. It saved me from ruining any of the oak, expecially with those expensive bits. The landing feels rock solid too; I checked the deflection and we have almost zero bounce. I’m just glad the heavy lifting is done and I can finally focus on the handrails.