Assemble Main Shelf Box
From Under-Stair Shelving · Step 7 of 10 · Video by Robert J. Keller

Showing 2:26–2:55 of the source video. Watch the full video with every moment.
What happens in this clip
The main box of the shelving unit is assembled. Wood glue is applied to the edges of the bottom shelf piece and the end panels. These pieces are then brought together, held with clamps, and secured permanently with screws using an impact driver. This forms the foundational structure of the shelf.
What's used
Tools
- Clamps
- Impact Driver
- Plywood Panels
- Screws
- Wood Glue
About the full video
This project guides the user through building a custom wall-mounted power tool shelving unit featuring adjustable vertical dividers. The process involves precise cutting of plywood, routing dadoes to create slots for the dividers, assembling the main shelf box, and securely mounting it to a wall. The adjustable dividers allow for flexible compartment sizing to accommodate various power tools.
Step 7 of 10: Assemble the Main Frame
Begin assembling the main structural components of your shelving unit. Apply wood glue to the joints and secure them with screws. If your design includes a back panel or vertical dividers, attach them now. Ensure the frame is square and sturdy.
Every video in Under-Stair Shelving
Step 1: Measure the Under-Stair Space
- 1:09–1:46 Measure, Cut, and Test-fit
- 0:09–1:25 Initial Measurements and Platform Design
Step 2: Design the Shelving Unit
- 0:13–0:17 Install Modular Shelving Frames
- 2:57–3:12 Construct Wider Center Shelves
Step 3: Create a Cut List
- 3:46–5:30 Create Cut List and Verify Thickness
- 0:38–1:39 Prepare Lumber and Cut List
- 0:02–0:04 Cut and Prepare Lumber
Step 4: Purchase Materials
- 0:00–0:03 Gather Materials and Tools
- 0:00–0:17 Gather Materials and Tools
- 0:00–0:49 Gather Tools and Materials
Step 5: Cut the Materials
- 1:03–2:43 Cut All Lumber to Size
- 1:18–1:29 Cut Timber to Length
- 0:11–0:58 Cut and Rip Lumber
Step 6: Sand All Pieces
- 1:24–1:29 Sand All Components
- 2:06–2:19 Sand All Cut Pieces
- 0:27–0:30 Sand Wood Pieces
Step 7: Assemble the Main Frame
- 2:26–2:55 Assemble Main Shelf Box (this video)
- 1:05–1:57 Assemble Vertical Side Frames
- 0:06–0:11 Assemble the Main Frame
Step 8: Install Shelves
- 5:42–6:03 Install Reinforced Shelves
- 4:56–5:53 Install Internal Divider Shelves
- 5:19–5:45 Install Shelves
Step 9: Finish the Unit
- 0:39–0:49 Paint and Install Hardware
- 0:43–0:49 Paint All Wood Components
- 12:47–13:48 Apply Wood Finish
Step 10: Install the Shelving Unit
- 3:20–4:12 Install & Secure Bookcase in Alcove
- 3:22–6:20 Install Shelf Units and Supports
- 0:13–0:17 Install Modular Shelving Frames
Questions about Under-Stair Shelving
What are the essential tools I need for accurate measurements in an angled under-stair space?
Beyond a standard measuring tape and pencil, an angle finder or a protractor is crucial for accurately capturing the slope of the stairs. Also, a long straight edge or level will help you mark level lines and check for plumb, ensuring your shelves are straight and true despite the angled surroundings.
Beyond basic hand tools, what power tools would make this under-stair shelving project easier for a beginner?
A miter saw or circular saw with a guide will significantly improve the accuracy and speed of cutting your lumber, especially for repetitive cuts and angles. An electric orbital sander is also highly recommended to efficiently prepare all pieces for finishing, saving you hours compared to hand sanding.
What are the most important safety precautions I should take when cutting and assembling lumber for this project?
Always wear safety glasses to protect your eyes from sawdust and flying debris. Use hearing protection when operating power tools and ensure your work area is clean and well-lit to prevent accidents. Make sure all lumber is securely clamped or supported before cutting to avoid kickback.
The project is listed as 'beginner' and '3 days'. Is this estimated time realistic for someone completely new to woodworking?
While classified as beginner, the 3-day estimate often assumes some prior familiarity with tools and a focused work schedule. If you're completely new, allow for extra time, especially for careful measuring, precise cutting, and thorough finishing, as these steps are critical for a professional-looking result. Don't rush the process.
What's a common mistake beginners make when measuring for under-stair shelving, and how can I avoid it?
A frequent mistake is not fully accounting for irregularities in the wall or floor, or failing to precisely capture the stair's varying angles, leading to shelves that don't fit snugly. To avoid this, create a detailed template using cardboard or scrap material for complex angles, and always 'measure twice, cut once' to confirm dimensions.
Are there alternative materials to dimensional lumber that might be easier for a beginner or offer a different look for under-stair shelving?
Plywood or MDF (medium-density fiberboard) can be good alternatives, often providing flatter surfaces and being easier to cut into large panels for shelves and backs. These materials typically require edge banding or painting for a finished appearance, which might add a different aesthetic and complexity to the finishing steps. Consider pre-made shelving kits for the simplest approach, though customization will be limited.
Under-Stair Shelving
Design and construct open shelving or a bookcase unit to fit within the under-stair space, maximizing storage and aesthetic appeal.
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