Introduction: Portable Water Resistant LED Picnic Blanket With Hard Center Serving Surface!

About: artist/designer

Here in Los Angeles there are a bunch of places to picnic in the evenings and watch an outdoor movie,
like Cinespia in the Hollywood Forever Cemetery. This sounds scary, but when you have your own vinyl picnic blanket to spread out on the lawn, to protect from damp and spirits, with its own built in light source under a milk plex center table area, everyone can see what they're dishing up and which bottle is the red wine! I've designed this thing to fold up for easy transport to to run for 4-6 hours on rechargeable AA batteries.
Here is what you'll need:
Battery op 64 LED String (I bought mine from Dayva)
Milk Plex, I used a 16 x 18.5 x 1/8" lightbox top I had around
Vinyl with fuzzy backing, I used 3.5 yds Gray for the back (to match the straps) and 3.5 yds White for the top.
20 x 24 piece of clear .40 mil pvc sheeting to water resist the top.
2 yd Webbing for the handle and strap
2 plastic buckles
Velcro for the battery compartment.
5 AA NI-MH 1.2V 2300MA batteries.
6 AA cell holder with snap connection.
Cord w/9 V clip to 2.1MM x 5.5MM (+) center.
A push button canopy switch.
Jack to Jack connector 2.1MM x 5.5MM
Zap a Gap
Duck tape
A lighter
8 1" binding posts
silicone seam sealant
electric crimps
nut and bolt or spring for missing # battery
24 x 36 sheet of green 1/2" foam
8" of 2" white velcro

Then tools wise:
scissors and I like to use my electric cutter
Belt punch
sewing machine
rulers
Drill and bit for plexi holes
wire strippers for to add the switch to the electric rig.
Strong pins
a thimble
Spray mount

Step 1: Cut Your Vinyl and Pvc Window

I made this blanket roughly 80" x 92". I pieced the top in 3 sections.
The two largest measure 32 x 92, these follow the top and bottom and I filled in with two skinny pieces
@ 17" x 30 and set the pvc piece between them. This is based on 1/2 seam allowance, except for around the center pvc frame, where I will double up the seam allowance at 1 ".
Minus the pvc section, you'll want three pieces of grey vinyl cut and assemble as well, so get stitching!

Step 2: Plexi Table Top

I happened to have a 16" x 18.5" piece of milk plex, but you can work with whatever size you want.
You'll want to drill 3/16 -ish holes to accept the threaded screw of your binding posts. These will also serve as the "legs" for the table. So I used 8 holes, 4 on side centers and the others set in two inches from the ends of the 18.5 length side. It is a good idea to trace the top and mark where the holes are located, you will use this later. Take the trace and mark the hole locations on the frame side pieces of the white vinyl you just cut.

Step 3: The LED Layer

Take your plexi top and trace it to a scrap of the leftover vinyl. This will be your LED mounting layer. Mark the attachment holes!!!
Measure out a 2" x 2" grid. Punch a hole into the center of each of the 63 boxes using a belt punch. Trim the holes clean. Get out your Zap a Gap. Start with the end of the LED string and position glue around the collar of each light, so that when you press them through the punched hole, they will be secured to the vinyl. These lights are on 6" increments, so we'll have some wire to manage as we go.
Continue this tedious process for the rest of the lights. Look on the bright side, at least we are not wiring each LED ourselves!
Use some duct tape the manage the cords around the outside perimeter. Now punch through this at the attachment holes.

Step 4: Wire Up Your Rig.

Discard the bulky 4D battery case that came with your lights. We need something smaller. Find your 6 AA battery holder attach to the 9V clip. Cut the positive to attach the switch. Strip your leads and secure with crimps. Attach that to the female to female jack and attach the male jack from the LEDs.
Now take 5 charged 1.2V batteries and a bolt and nut or spring to round out the empty 6th spot and load up your holder. Check to see the LED rig lights up!

Step 5: Check Your Diffusion

Now you can play around with the distance between your LED layer and your plexi top.
I liked how 1" binding post offset the hotspots a bit without getting too high in profile

Step 6: Hiding the Rig

I decided to soften the transition between my one inch table and the rest of the blanket with a frame made from two layers of 1/2" green foam. I also notched out of the foam at resting place for the battery holder and the switch. I also just tucked the 64th LED into the side of the foam frame, you never see it in the end. This allowed me to set these off a bit from the table, as I don't want spills to head into the electrics. The PVC layer helps this and if you want to, you can silicone the seams between the vinyl and PVC before topstiching.
Spray the back of the foam frame and center in on the grey vinyl layer. Let this set up and check to see it is secure. If not stitch through it to the backing, my machine will do this but if yours can't just tack by hand.

Step 7: Make Some Necessary Final Cuts

Identify where the switch needs to be and punch a hole here. Carefully cut a slit for battery access.
Use 1" white velcro to edge this slit top and bottom. Next measure out a cover for the battery compartment and line completely with opposite white velcro, best case 2" here.

Step 8: Assemble Your Handle and Strap

Take the webbing and cut in two equal pieces.
Cut one in half again burn the cut edges to seal them with a lighter and stitch these to a black clip buckle, and reinforce with a few more stitches.
From the other length make a suitcase type strap by attaching ends to the other buckle.

Step 9: FInal Assembly

Crawl under your white top surface and carefully secure the previously punched holes, concealed beneath the top stitching to your plexi. You'll want to use your handly Instructables multi-tool to tightening the binding posts. Now you have to stack the gray vinyl right side out and center the plexi LED sandwich into the green foam frame. Find your switch and attach collar/canopy. Carefully line up the edges on fold 1/2" inside and pin, all the way around, and use a thimble because this is four layers of vinyl! Insert your handle ends into the seam on one of the center sides. Move this system to your machine and top stitch that outer edge all the way around.

Step 10: Wrap It Up!

Fold your blanket in thirds and secure with the separate buckle strap. Pack up your picnic and head out into the night!