Post #927: Wheelchair floor-to-chair aid, V3

Posted on December 26, 2020

The brief for this task:  Create a floor-to-chair aid for wheelchair users.  It must be able to be made at home, using only simple hand tools and readily available materials.

The end result is shown directly below.

Above:  Floor-to-chair aid, folded and covered.  For scale, the push-up bars sitting on top are 6″ tall.

Above:  Rear view, folded.  Lower stairs sit atop upper stairs when folded.  The boxes nearest the camera flip away from the camera when put into use.

Above:  Rear view, unfolded.  Lower stairs have been flipped off the top, away from camera, revealing hardboard stair tops.  Push-up bars are on top.

Above:  Front view, folded.  Blue cloth connects the lower and upper sections of the staircase.

Above:  Front view, unfolded.  Lower stairs have been flipped off the top, toward the camera, revealing hardboard stair tops.  The blue cloth keeps the upper and lower stairs connected.


Introduction

Background:  This post provides instructions for making a simple aid to allow wheelchair users to get from floor to chair (and vice-versa), as long as they have adequate hand/arm strength.  The aid is a broad, shallow, portable four-step staircase, made from cardboard and hardboard, along with a standard set of pushup bars.  The user mounts the staircase backward, using the pushup bars to lift themselves up each step.  If you want more background on the need for such a device, and how these plans evolved, scan Post #886, Post #913, Post #914, and Post #917. Post #886 has plans for a wooden, carpeted, non-folding version of this staircase.

General overview of construction:   This is a set of 20 identical cardboard boxes, taped together to form a staircase.  Eight boxes (the steps) are reinforced internally with cardboard, and externally with hardboard tops.  The reinforced steps spread the user’s weight over the empty boxes that make up the body of the staircase.  The staircase is divided into two pieces, connected so that they can be stacked when not in use, but easily deployed when needed.

Materials, cost, tools, time.  Detailed lists are given below.  Briefly:  Corrugated cardboard boxes, sheets of hardboard, tape, scraps of twine or thin rope, fabric, and a bit of glue.  Total materials cost is about $55.  You only need a few simple hand tools to build it, mainly a utility knife, but also a straightedge, tape measure, and C-clamps.  If you have full use of your arms and hands, this should take about four hours to build.

Weight and dimensions:

  • Each step is 4.5″ high, for a total height of 18″.
  • Each step is 12″ deep x 32″ wide.  This to accommodate the user and the pushup bars side-by-side.
  • The staircase folds when not in use, making a rectangular solid 32″ x 24″ x 22″.
  • The staircase weighs 26 pounds.

Instructions in brief

  • Buy a pack of 25 boxes, 16″ x 12″ x 4″.
  • Make internal supports using corrugated cardboard cut into 4″ widths.
  • Score and cut hardboard to provide a durable step-top surface.
  • Fill eight boxes with the 4″ cardboard supports.  Tape shut.  These will form the steps.
  • Tape 12 empty boxes shut, adding handles to four of them.  These will form the rest of the staircase.
  • Tape all of that together in two pieces — lower two steps, and upper two steps.
  • Connect the lower and upper parts of the staircase with a broad strip of cloth.
  • Tape on the hardboard stair tops.

Optionally:  You can make a cardboard cutting jig first, to make the cutting more accurate.  See Post #926.  I used that jig, and while it made the cutting more accurate, it didn’t make it any faster.

Optionally:  You can cover the steps with a carpet remnant.  These instructions don’t include carpeting the steps.  Home Depot sells carpet remnants of about the right size for $10.

Major caveat:  This takes significant time and labor to build.  It looks pretty basic, but it involves a lot of cutting up cardboard and taping boxes together.


Instructions in detail

I have set this up to do the most labor-intensive parts first.

Note 1:  Throughout, I  number the physical stairs 1 to 4, starting from the bottom.  The lower staircase is steps 1 and 2, the upper staircase is steps 3 and 4.

Note 2:  Hardboard (with-an-h) is a completely different material from corrugated cardboard. 

Materials list:

  • 6″ tall push-up bars, $12, available from Amazon.  If you don’t buy these exact bars, buy the tallest ones you can find that will fit onto the 12″ x 32″ step.  Anything over 6″ tall should work reasonably well.
  • One pack of 25 corrugated cardboard boxes, 16″ x 12″ x 4″, $23.50, available from Amazon.  Prices seem to vary from week to week.  Substitute 15″ x 12″ x 4″ if that’s cheaper, and modify the hardboard cutting measurements accordingly.  Five of these cartons will go unused.
  • Two 2′ x 4′ sheets of 1/8″ thick hardboard, $8 total, available from Home Depot
  • Two rolls high-quality packaging tape, $8 total, available from Home Depot.  OR one large roll high-quality duct tape.  You will need at least 50 yards of tape.
  • Four short (18″-20″) pieces of cord (heavy twine, paracord, clothesline, etc.)
  • Some scrap corrugated cardboard cartons, in addition to the ones purchased above.   About half this cardboard will end up as waste, as you cut it up.  In total, including waste, you’ll probably need about 160 square feet of scrap cardboard, equivalent to four to six “large” moving boxes. 
  • A piece of thin cloth roughly the size of a pillowcase.
  • A bit of Elmer’s Glue-All or similar glue made for porous materials.
  • Optional:  Carpet remnant from Home Depot, $10.
  • Optional:  Glue for attaching carpet remnant, Home Depot $3.

Tools list:

  • A utility knife and spare blades.
  • Large cutting board, plywood scrap, or other surface you can cut on.
  • A long straightedge (metal is strongly preferred, 3-foot or longer preferred).
  • OR a cardboard-cutting jig ( see Post #926).
  • Two small (e.g., 2-inch) C-clamps.
  • Tape measure.
  • Sharpie and pencil.

Step 1:  Cut up the cardboard reinforcements, 1 hour.

  • 48 pieces of corrugated cardboard, 12″ exactly x 4″ exactly.
  • 48 pieces of corrugated cardboard, roughly 18″ x 4″ exactly .

Using tape measure, straightedge, and utility knife (or cutting jig), cut the scrap cardboard cartons into 4″ strips, then cut those strips to the lengths listed above.

The corrugations must run in the 4″ direction.  Each time you cut, you will be cutting across the corrugations.  See the “accordion” photo below if you are still unsure of what I mean.

The 4″ dimension is important.  Cut these too tall, and the boxes will bulge.  Cut them too short, and they won’t support the weight.  Take as much care as you can, or construct and use my 4″ cutting jig.

This step will leave you with a large pile of cardboard scraps left.  It is best to set up a trash bag or box to hold those, before you begin.

Almost any sort of packing box provides adequately strong corrugated cardboard.  Small Amazon delivery boxes are fine.  But I would avoid the thinnest cardboard, such as that found in pizza boxes.  Look for a stamp that says ECT 26 or higher.  Or just compare the thickness to that of the pack of 25 boxes that you bought.

2:  Score and cut the hardboard step-tops:  40 minutes.

Use the utility knife, straightedge, and clamps to cut the two pieces hardboard up neatly, so it can be used as a durable top surface for the four steps.  You score the hardboard heavily with the knife, bend it a bit, and keep cutting until the pieces separate.  From the two 4′ x 2′ hardboard sheets, you end up with:

 

 

  • 4 pieces 12″ x 32″, to cover the step-tops.
  • 2 pieces of scrap, 24″ x 16″

2.1  Score and cut the ends off both pieces.

  • Place one piece of hardboard on the table, good (shiny) side up.
  • Put two marks 32″ from the end, one on either edge.
  • Align and clamp the straightedge on those marks.
  • Score it repeatedly with the utility knife, starting with light pressure, and slowly increasing pressure.
  • After five passes with the knife, you should be able to move the knife quickly down the existing groove.
  • After 15 passes with the knife, bend slightly, and continue to score until knife begins to pass through the board in places.
  • At that point, fold the board into a right angle, set it upright, pass the knife through from the back side, and finish the cut by drawing the knife straight up, flipping the board, and drawing the knife straight up again.
  • Repeat with the other piece of hardboard.

2.2  Score and cut both boards into step-sized (12″ x 32″) pieces.

  • Take one 32″ piece of hardboard.
  • Measure and mark 12″ in from the long end.
  • Clamp, score, and cut as above.
  • Repeat.

Step 3:  Assemble and fill 8 cartons to form the steps, 30 minutes.

For each carton, take six 18″ x 4″ pieces of scrap cardboard, and six 12″ x 4″ pieces of scrap cardboard.  Fold each long piece in half to form a “V”, fill the box, and wedge those in place with the short pieces.

  • Tape the bottom shut on a carton.
  • Take six long support pieces (18″ x 4″), bend them in half into a “V”.
  • Re-stack those pieces so that the folded ends alternate.  (I.e., flip the first, third, and fifth pieces end-for-end.
  • Fill the box with six “V”s, letting them “accordion out” to fill the box.
  • Place one short (12″ x 4″) piece in each “V”, forcing the “V” against the wall of the box.
  • Neaten up all the pieces so that they are as evenly spaced as possible.
  • Close the flaps and seal the box with tape.

Above:  Six “Vs”, and those “Vs” with 12″ center supports installed.

Step 4:  Assemble 8 empty cartons, 10 minutes.

Tape the top and bottom flaps up to form up the box.

Step 5:  Assemble 4 empty cartons with handles, 15 minutes.

  • Tape up the bottoms of four boxes, but leave the tops open.
  • Cut handle reinforcements.  Cut four small (2″ x 12″ or so) scraps of cardboard.  Double them over and tape them.  Then tape one to the inside of each box, near the top.
  • Place the box on the cutting board and cut through the reinforcement all the way to the outside of the box.
  • Stick a pencil through the point where the cuts pass through the box.  Do this from the outside, then from the inside.
  • Use the pencil to poke the 18″ to 20″ pieces of cord through those holes, one piece per box.  Neaten it up so it’s not twisted, and tie it together on the inside.
  • Seal up the top of the box.

Above:  Reinforcement and handle, inside of box.

Step 6:  Tape the cartons together, lower steps separate from upper steps, one hour.

In this task, you tape the boxes together to form the completed staircase.  But you do that in two pieces, so that the stairs can be stacked when not in use.  The lower two stairs (1 and 2) form one unit, and the upper two stairs (3 and 4) form a second unit.  A piece of cloth connects the two.

6.1  Tape pairs of boxes together, end to end.

  • Pair up empty boxes with handles, two at a time, end-to-end
  • Align them, and tape them together.
  • Use a couple of pieces of tape, widely spaced, to tape them together, top and bottom.
  • Tape over the gap between the boxes on both sides.
  • Repeat until you have two pairs of empty boxes with handles.
  • Pair up boxes that are reinforced, two at a time, end to end.
  • Tape them up as above.
  • Repeat until you have four pairs of reinforced boxes.
  • Pair up the remaining empty boxes without handles.
  • Tape them as above.
  • Repeat until you have six pairs of empty boxes without handles.

6.2  Tape together the upper two stairs (3 and 4).

Start at the bottom of this portion of the staircase, construct layers of boxes, tape those layers together, and work your way to the top.  The most important thing is to keep the layers vertically aligned, so that they will bear the load properly.

Decide where you want your handles to go before you start taping.  I put the handles directly under stair 2 and stair 4.  If you want that configuration, then you have to remember to place those boxes with handles in the right spots as you tape this together.

  • First and second layers:
    • Align two pairs of empty boxes, size by side.
    • Tape them together to form a four-by-four rectangle.
    • Flip over and tape the underside as well.
    • Repeat.
  • Third layer.
    • Align one pair of empty boxes and one pair of reinforced boxes.
    • Tape them together to form a four-by-four rectangle.
  • Tape the second layer to the first layer.
    • Start at one corner, align boxes, tape the corner vertically.
    • Move to the diametrically opposite corner, align boxes, tape the corner vertically.
    • Tape them vertically across the joints between the boxes in the layers.
  • Tape the third layer to the second layer, as above.
  • Fourth layer:
    • Tape two reinforced boxes to the third layer, above the empty boxes.

6.3:  Tape together the lower two stairs.

At this point, this should be obvious.  This is identical to the third and fourth layers above.

Step 7:  Tape the hardboard step tops onto steps 1, 2, and 4,  ten minutes.

Center the hardboard on the step, tape around every accessible edge of the hardboard, sticking the tape to the cardboard.

Do not put the hardboard onto step #3 yet.

Step 8:  Add cloth fall to connect the lower and upper steps, and tape hardboard top to step 3, 20 minutes (plus drying time).

Use a pillowcase or thin piece of cloth roughly the size of a pillowcase.  Glue this cloth to connect the lower and upper sections of the staircase, allowing just enough slack in the cloth so that the lower stairs fall into the correct position when they are needed.

The crude diagram below shows that you will glue the cloth to the top of the third stair, and the back of the second stair.  However, contrary to what the diagram shows, there should be no slack in the cloth when it is glued in place.  So this next section goes through the steps to get that cloth attached correctly.

8.1  Tape and glue cloth to back of lower staircase (stair 2).

  • Hang the lower staircase on the edge of a table, with stair 1 facing down, and the back of stair 2 facing up.
  • Brace that in place with a chair or similar object.
  • Glue your cloth to the back of the lower staircase.  Let it hang over stair #2.
  • Tape it in place so that you can move this in the next step.

8.2  Stack staircases, tape and glue cloth to top of stair #3.

  • Take the upper staircase and sit it on its back, i.e., stair 3 above stair 4.
  • Take the lower staircase and stack it on top of the upper staircase.
  • In effect, you now have the entire staircase, sitting upright instead of lying on the floor.
  • As shown below, stair 1 is at the top, stair 4 is at the bottom.
  • The cloth you just glued in place is now trapped between the back of stair 2, and the front of stair 3, and is weighted down by the lower staircase.
  • Cut the cloth to size, as shown.

  • Now glue the cloth to the tread portion of stair #3, and only to the tread portion.  Don’t glue it to the front (riser) portion of step 3 — that has to remain unattached.
  • Finish by taping the hardboard top of stair #3 into place, to keep the glued cloth in place.
  • Leave it to dry, preferably overnight.

9:  Fold and tape to move, cut that tape when in the final destination.

Once dry, carefully set the staircase on its bottom, then fold the lower staircase onto the upper staircase, as shown in the photos at the top of this posting.  Add a piece of tape or two in the back, to hold this in place as you move the stairs to their final location.  Cut that tape once you get this to its destination, so that it can be unfolded readily when needed.