Black Locust Adirondack Set

Project Overview — Three Pieces, One Cohesive Set

Key Dimensions — Tuned for Your Two Users

These dimensions account for a 5'6" / 180 lb user and a 5'10" / 135 lb user, with consideration for occasional infant-holding use. Where ranges appear, the lower value favors the shorter user and the upper favors the taller.

Wood Species — Why Black Locust

★ Buy kiln-dried, surfaced (S4S) black locust from a regional hardwood dealer. Purchase 10–15% extra per chair to account for learning cuts on the first locust build. In CT, try Granby Sawmill, Berkshire Products, or any NE hardwood dealer sourcing Appalachian stock.

Material Specifications

Cut List — Per Piece

All dimensions are finished (after surfacing). Multiply chair quantities by 4 for the full set. Build ottoman and side table after chair prototype is confirmed. All curved cuts (front seat edge, back fan, front legs) require a jigsaw.

Adjustable Back — Dowel Pin Mechanism Detail

Shopping List — Full Project

Tools — Buy vs. Already Own

Build Order — Step by Step

1. 1
   Buy Tools & Pine — Set Up Your Work Area

   📋 Before anything else

   Purchase your miter saw, jigsaw, and chisel set. Pick up pine prototype lumber from Home Depot. Set up a basic work area — two sawhorses and a sheet of plywood as a workbench is sufficient to start. You don't need a dedicated shop; a garage or driveway works fine for this project.

   ✓ Watch 2–3 YouTube videos on miter saw safety and basic jigsaw technique before you make your first cut. Black locust is hard; getting comfortable with your tools on pine first is time very well spent.
2. 2
   Build the Pine Prototype Chair — Complete Assembly

   📋 Phase 1 — prototype (do not skip)

   Cut every chair part from pine using the cut list dimensions. Assemble the full chair using the pine with regular screws (don't bother with stainless yet). Cut the rear leg slot and test the dowel pin mechanism in all three positions. This is your geometry test — get every angle right here, not in locust.

   ⚠ Do not rush past this step. Sit in the chair yourself. Have your partner sit in it. Simulate holding a baby. Check armrest height feels natural. Check getting up is not a struggle. Adjust any dimensions that feel off before you cut a single piece of locust.
3. 3
   Make Hardboard Templates from the Prototype

   📋 Phase 1 — template making

   Disassemble the pine chair and trace every unique part onto ¼" hardboard. Cut the templates with a jigsaw. Label every template clearly (e.g. "REAR LEG — slot on inside face"). For curved parts, the template carries the exact curve so you never have to re-draw it. These templates are the most valuable thing you make in this entire project — they ensure all 4 chairs are identical.

   ✓ Sand template edges smooth — they will be used as router or jigsaw guides. A rough template edge transfers rough curves to every piece you cut from it.
4. 4
   Order Black Locust Lumber

   📋 Phase 2 — material acquisition

   Call your hardwood dealer with your confirmed cut list (from the prototype) and request kiln-dried, S4S black locust in 4/4 and 8/4 thicknesses. Order 12–15% more than you calculate you need. Ask for boards from the same drying batch if possible — this helps with color consistency across a 4-chair set. Expect 2–4 weeks lead time if they don't stock it.

   ✓ When the lumber arrives, let it acclimate in your work area for at least 1 week before cutting. Freshly delivered kiln-dried lumber may still need to equilibrate to your local humidity — especially important in CT where indoor and outdoor humidity swings dramatically by season.
5. 5
   Cut All Parts for All 4 Chairs at Once

   📋 Phase 2 — milling day

   Using your templates and the miter saw, cut all parts for all 4 chairs in a single session (or over 1–2 days). Organize parts by type in labeled piles — all rear legs together, all seat slats together, etc. This batch-cutting approach ensures consistent lengths across the set and means your tool setups (miter angle, stop block positions) only happen once per part type.

   ⚠ Pre-drill every screw hole before assembly — black locust is a dense hardwood that will split without pilot holes, especially near ends and edges. Use a countersink bit sized for #8 screws. This takes time but prevents expensive mistakes.
6. 6
   Cut Dowel Slots in All Rear Legs

   📋 Phase 2 — mechanism work

   Mark the slot position on all 8 rear legs (2 per chair × 4 chairs) using your template. Cut the slot sides with a jigsaw — make two parallel cuts, then chisel out the waste. Cut the three notches with a chisel. Test each slot with a dowel pin before moving on — the fit should be snug but smooth. Do all 8 legs before any assembly begins.

   ✓ Make a simple jig from scrap pine to hold the rear leg at a consistent angle while you chisel the notches. Consistency across all 8 legs is what makes the set look intentional rather than improvised.
7. 7
   Apply Pre-Assembly Finish to All Parts

   📋 Phase 2 — finishing (before assembly)

   Sand all parts to 150 grit, then 220 grit. Apply your penetrating oil (Rubio Monocoat or Osmo) to all faces and edges of all parts while they are still flat and easy to access. Critically, seal all end grain with Anchorseal or a thin coat of epoxy — this is where moisture enters and where rot begins, even in locust. Allow full cure time per product instructions before assembly.

   ⚠ Do not finish the glue surfaces or screw contact areas — oil contamination prevents good mechanical fastening. Leave a 1" band around every screw location unfinished; you can touch these up after assembly.
8. 8
   Assemble First Locust Chair — Confirm Before Batching

   📋 Phase 3 — first chair assembly

   Build one complete chair using the finished locust parts. Start with the leg assembly, then attach seat supports, then slats, then back assembly, then armrests. Use clamps generously. Check square at every major step — a chair that's slightly racked will rock on any flat surface. Test the back mechanism through all three positions before attaching armrests (easier to access the slot this way).

   ✓ Have your partner sit in this first locust chair before you build the remaining three. It is much easier to adjust one chair than four. Confirm height, armrest feel, and back positions all work as expected with both users.
9. 9
   Assemble Remaining 3 Chairs

   📋 Phase 3 — batch assembly

   With your assembly process confirmed and parts already pre-drilled and pre-finished, the remaining three chairs go together significantly faster than the first. Work one chair at a time rather than trying to assemble all four simultaneously. Apply touch-up finish to any raw areas exposed by assembly. Let each chair cure fully before moving outdoors.
10. 10
    Build Ottomans (×2)

    📋 Phase 4 — ottoman build

    With the chairs complete and dimensions confirmed, cut and assemble the ottomans. The ottoman height (15") and slat spacing must match the chairs exactly — place a chair next to the ottoman during assembly to visually confirm the relationship. Apply the same finish process: sand, oil, end-grain seal, then assemble.

    ✓ Build both ottomans in the same session so your miter saw setups stay consistent. The ottoman is the simplest build in this set — it should take 3–4 hours per unit once you have the process dialed from the chairs.
11. 11
    Build Side Tables (×2)

    📋 Phase 5 — side tables

    The side table is the most forgiving piece in this set. Cut four tapered legs, four mitered apron boards, and three top slats per table. Assemble the apron box first (using pocket screws from inside the apron), then attach the legs, then lay the top slats. Confirm the table surface height matches armrest height (25–26") before fastening the top permanently.

    ⚠ The 45° miter cuts on the apron corners are the trickiest cuts in the side table. Make several test cuts in pine scrap at your miter saw's exact 45° setting before cutting locust apron boards. Even a half-degree off produces a visible gap at the corner.
12. 12
    Final Finish Pass & Touch-Up

    📋 Phase 5 — final finishing

    Once all pieces are assembled, do a final light sand (220 grit) on any assembly marks or dings, and apply a second coat of penetrating oil to all exterior surfaces. Pay special attention to end grain, the underside of armrests, and the underside of seat slats — these are the areas most vulnerable to CT weather. Allow full cure before setting out.

    ✓ Set the completed furniture outside in a shaded spot for 1–2 weeks before full exposure. This allows any remaining solvent in the finish to off-gas and the wood to acclimatize to outdoor humidity before the first rain hits it.

Cost Summary