Armrest Side Table with Remote Caddy (Parameterized)

I created this a few years ago after seeing a very nice bent plywood side table that came with a couch. I didn't want that couch, but I really liked the look of the side table, and it seemed like a great place to add a remote control caddy. I didn't have the tools to bend and laminate plywood for my own table, but I did have a 3D printer and I really enjoy projects that spotlight the kind of on-demand customization that 3D printing allows. So, this is the result.

We've been happily using this table for about three years, but I've only just cleaned up and published the design for the Print Tables contest. I figured that since I already had an entirely 3D printed table, I might as well share the design and enter.

Instructions

Unless your armrest is exactly the same size as mine, you should not use the included STLs. They're really included only as a visual aid. Instead, you need to take measurements of your own furniture, set the dimensions in Fusion 360, and then export the right mesh files for your size printer. The following instructions should walk you through that process.

Measurements

The dialog you'll need in Fusion 360 is available from Modify → User Parameters. The critical dimensions are:

• arm_width - The width of the opening of the table that fits over your armrest.
• arm_height - The height of your armrest, plus 30mm or so below the cushion.
• table_length - The back-to-front length of the table.
• cubby_depth - The distance the remote control cubby cavity extends past the outside of the table.

There are a whole bunch more options that you could modify to drastically change the style or other aspects of the table, but you shouldn't need to worry about those.

Model Splitting

Once you've updated the dimensions you can select the models you need to print. If you have a big printer (I used a CR-10 originally) then you can just export the mesh for the table_body_one_piece component, and print the whole thing on its side in one go.

If your printer is wide enough for the full armrest height but not tall enough for the full table length, then you'll need to to export both bodies in the table_body_mid_split component. The models are split with a tongue and groove that glue together; both the table_body_left_piece and table_body_right_piece halves will need to be printed on their outside edges, with the mating sides at the top of the print.

If your printer is tall enough for the full table length but not wide enough for the full armrest length, then you'll need to to export both bodies in the table_body_arm_split component. The table_body_top_piece is printed on either the front or back side, as with the single piece print. The table_body_bot_piece is printed with its bottom edge on the bed and the mating groove on the top; you will likely need to rotate approximately 45º around the Z axis to fit the bed.

If your printer is neither wide enough nor tall enough for either of the two-way splits, you will need to export the three bodies from the table_body_tri_split component. The print orientation for all three pieces is described in the previous two paragraphs.

Testing Fit

You can print the two halves of the fit_test component (the mating edge of each piece must be oriented on top) to verify that the tongue and groove of the split models fit together properly. You want feel some friction when you slide the pieces together, but not so tight that the print bulges at the seam from the pressure. You can increase your extrusion multiplier in the slicer to get a tighter fit, or reduce it to loosen the fit.

Gluing up

I prefer using a high quality wood glue and clamps for large wood-fill PLA pieces with good joining surfaces (such as the tongue-and-groove fit in these models). In my experience it holds up well, gives enough open time to ensure everything can be properly aligned, and has the benefit of good compatibility with the wood fillers and stains used in finishing. Just make sure to give the glue at least two days to fully cure before moving on to sanding and finishing.

If you can't clamp the parts, then place the glued up table_body_left_piece and table_body_right_piece assembly on its side on a flat surface (such as the floor or a table) with a wide enough board on top (or even a large book), and stack enough weight on top of that to close the seam while the glue sets up.

If you need to glue the table_body_bot_piece without clamps, painters tape should hold adequately while the glue is setting up. Afterwards you may need to use wood filler on any visible gap, but since this seam is at a right angle “grain” intersection and not very visible in use, it shouldn't hurt the appearance.

Dividers

Export a mesh from the divider component and print as many dividers as you think you may need. The print orientation is just the large flat edge (I like the finish that a textured bed gives). Choose whatever colors you find complementary to the main table body and your own decor. You could even swap them out seasonally if so inclined.

The printed dividers should just slide into the cubby insets, spaced appropriately to fit your remotes or other devices (e.g. chargers) that you like to keep handy.

Faux Wood Finish

I've created number of faux wood prints using this finishing approach:

1. Print at higher layer heights and wider extrusions (ideally using a larger nozzle) with a wood fill PLA in the color range of the raw wood you intend to emulate.
2. Glue any pieces together with a high quality wood glue, clamping as needed, and allow at least 48 hours for curing.
3. Lightly sand the whole piece with a very rough paper (e.g. 80 grit).
4. Get a stainable, trowelable wood filler (or add extra water to thin out a stainable, water-based wood filler) and add pigment to make the wood filler noticeably darker than the base color of the wood fill pla (this is the base for the darker part of the “grain”).
5. Use a wide putty knife to spread a thin skim coat across the entire print and allow it to completely dry.
6. Lightly sand again with a rough paper (e.g. 120 grit) so that it's smooth and retains a thin coat of wood filler over most of the surface with deeper woodgrain-like lines of filler between the voids in the layer lines.
7. Apply wood stain as you normally would, with finishing sanding as needed between applications; while staining you may find it useful to intentionally leave brush lines parallel to the extrusion lines, as they can break up any overly regular patterns from the layer lines.
8. Once you're happy with the look, seal the whole thing with a few coats of high quality polyurethane.