Quadcopter Landing Pad With Telescoping Legs for Uneven Ground

Quadcopter landing pad made of plywood. Telescoping legs allow takeoffs/landings from uneven ground. Folds in half for easy transport and storage.

Apologies for not taking photos step-by-step during construction--I have photos only of the finished product, so you'll have to use your imagination.

Materials

1. Half sheet of 15 mm (5/8") laminated plywood (actually about 18 mm thick with laminate included).
2. Plastic-head thumbscrews (optional): 1/4"-28, 1/2" long. McMaster-Carr part number 98704A710.
3. Piano hinge: stainless steel, with holes, 4 feet long. McMaster-Carr part number 1658A18.
4. 61 x #8 1/2" screws for piano hinge and securing stanchion bases: stainless steel. McMaster-Carr part number 90294A194.
5. 14 x 1/2" rubber bumpers: (two for "feet", remainder for cushioning hinged halves from each other). McMaster-Carr part number 9540K731.
6. 18 x #6 1" screws for layering plywood and securing bumpers: stainless steel. McMaster-Carr part number 90294A153.
7. Construction adhesive.
8. 3 x 60-degree stanchion bases: 3" x 7/8". https://jtsoutdoorfabrics.com/78--60%C2%B0-Round-Stanchion-Base--Stainless-Steel_p_15756.html.
9. 1 x 36 inch length of 3/4" Aluminum Tube - https://jtsoutdoorfabrics.com/3-4_inch_aluminum_tubing.
10. 1 x 36 inch length of 7/8" Aluminum Tube - https://jtsoutdoorfabrics.com/7-8_inch_aluminum_tubing.
11. 3 x Support Pole Length Adjuster - https://jtsoutdoorfabrics.com/Support-Pole-Length-Adjuster_p_20500.html.
12. 3 x Soft Nylon Pole Foot, Black, 3/4 inch - https://jtsoutdoorfabrics.com/Soft-Nylon-Pole-Foot--Black_p_20501.html.
13. Approximately 3 metres of 1" nylon webbing.
14. Plastic buckle, 1 inch.
15. 4 x 1/4" carriage bolts and matching washers and nuts.
16. Varnish (optional).

Tools

1. Saw for straight cuts: track, table, or circular.
2. Jigsaw or router.
3. Hacksaw.
4. Drill and bits.
5. Screwdriver.
6. Allen keys.

Cut desired size and shape of the entire landing pad from the plywood (i.e., not the separate halves).

I made mine octagonal, 100 cm across, using a track saw.

It would be possible to cut a circular pad instead, using a router or table saw, but this can be very dangerous if you don't know what you're doing or don't have the right equipment. Use caution.

Cut a rectangular strip of the plywood, about 24 cm wide and 6 cm longer than the width of your landing pad. My landing pad is 100 cm across, so I cut the strip to be 106 cm long.

Decide where the "top" of your landing pad will be when it folds. In the attached photo, this is where the blue webbing handle on the left is.

Mark the location of the leg flange on the plywood here by tracing the screw holes with a pencil. Subsequent steps are easier without the flanges installed, so do not secure them just yet.

If the "top" flange is zero degrees, then you need to mark the screw holes of the remaining two flanges at 120 degrees and 240 degrees, so they are evenly spaced in the angular sense.

Using construction adhesive and the 1" screws, secure the rectangular strip to what will be the underside of the landing pad (the attached photo is somewhat misleading, as it shows the strip in its finished form, after it has been cut in half lengthwise and had its ends trimmed--see the steps below).

The orientation of the spacer is important. It should run parallel to the two flanges that are not at the "top" of the pad when folded.

Using a track saw, a table saw, or a circular saw with a guide, cut the landing pad and the rectangular spacer in half lengthwise. This creates the two halves of the hinged landing pad.

The rectangular spacer is now two smaller long and skinny rectangular spacers secured to the underside of the landing pad. Trim one of these spacers down to be flush with the edge of the pad.

This will allow a foot to be attached later (see below).

Place the two halves of the landing pad face down on a bench (i.e., with the rectangular spacer upwards). Align the two halves carefully. Using the 1/2" screws, secure the piano hinge to connect the two halves.

You will probably have to cut the piano hinge to the correct length with a hacksaw. It's easiest to do this before securing the hinge to the plywood.

Using the 1/2" screws, secure the leg flanges to the underside of the pad at the pre-marked locations.

At this point, you can substitute thumbscrews for the set screws the flanges came with, but in that case, you will need to be careful when folding the landing pad--it would be possible to bend them if they are not screwed all the way in before folding.

Cut two small rectangles of the plywood to act as spacers to either side of the handle.

Secure them with construction adhesive and 1/2" screws.

Attach two rubber bumpers to each.

As built so far, the landing pad will not fold completely flat because the flanges collide with the plywood of the opposite halves.

If you have a router, you can cut away enough material to remove this interference. If you are using thumbscrews, make the hole large enough to accommodate them, too (I haven't done this yet, myself, but it seems a good idea to remove the risk of bending or breaking the thumbscrews when the pad gets folded).

If you do not have a router, use a jigsaw to cut notches or holes in the pad large enough to accommodate the flanges. This will result in the loss of only a very small portion of the landing area.

Use a hacksaw to cut the 7/8" tubing into three 1-foot lengths. Do the same with the 3/4" tubing.

Attach a "pole adjuster" collar to each length of 7/8" tubing using the set screw.

Insert the lengths of 3/4" tubing through the adjuster collars and into the 7/8" tubing.

Attach a nylon foot to the bottom of each leg.

Insert the legs into the flanges.

A little canvas bag for storing the legs is nice to have, but not necessary.

Drill holes for the carriage bolts where the handle is to go on one side of the pad.

Fold the pad and drill holes in the other half that line up precisely with the two holes you already drilled.

Insert the carriage bolts and use the nuts to secure lengths of webbing to serve as handles (this requires grommets to be inserted in the webbing. If you don't have access to a grommet tool, you could skip the use of carriage bolts. Just drill bigger holes and pass the ends of the webbing through them).

Add rubber bumpers to the ends of the carriage bolts. The bumpers on each side have to line up with their counterparts on the opposite side to work.

The attached photos show the two handles in the finished landing pad. Note the routed-out hole to accommodate the "top" flange when the pad is folded.

Cut another length of webbing and add a buckle. This will hold the pad shut when folded.

The rubber bumpers don't just protect the wood. By stopping the landing pad from closing too far, they prevent excessive strain being put on the piano hinge.

In this step, add four more bumpers to the half of the landing pad opposite to the two small spacers. Remember that they have to line up with their counterparts to work.

Add a bumper to the edge of the longer of the two spacers at each end. These will serve as feet when the pad is folded and set on its side, preventing damage to the piano hinge.

This explains why one of the two long rectangular spacers had to be trimmed flush with the edge of the landing pad. If both had been left sticking out 3 cm, there would be no space for feet when the pad was open.

Varnish the edges of the plywood to protect it from water absorption in rainy conditions.

Ready to fly!

1. Not really happy with the use of the bumpers to stop the landing pad from folding past 180 degrees. It was hard to line them up so they paired with their counterparts on the opposite half of the pad. Also, the rubber bumpers are already beginning to crack, and the screws securing them are wobbly. Consider an alternative: instead of two small plywood spacers on the same side of the pad, put the two spacers on opposite sides; instead of rubber bumpers, put a layer of felt or rubber mat on the spacers. This should be more robust than the little bumpers.
2. The feet that protect the piano hinge from damage by preventing it coming in contact with the ground when the pad is folded are made of the same rubber bumpers. They seem a little fragile for the purpose, especially since they are screwed into the end grain of the plywood. An alternative foot design should be found. It might even be practical to create the feet from the plywood itself: rather than cutting the pad fully in half, use a jigsaw to cut out a foot shape on the big rectangular spacer that sticks out each side of the pad and then cut the pad in half.