Introduction: Cheap DIY Childs Playset Tube/Tunnel

About: I am a father, musician and a DIYer
If you have ever priced a Play set tunnel, you know they are $500 + minimum.
I constructed this for about $20! 
Parts List:
10-  1"- 1/4" bolts
10- 1/4"  lock nuts
20 -  Washers
2- 55 gal plastic barrels (be cautios of former contents.  find food grade, or soap)
Mounting hardware: I used a spare swing, and lag bolts and washers.

Tools:
Drill
1/4' drill bit
jigsaw
ratchet and wrench

Step 1: Barrel Prep

Drill a pilot hole in the top.
Use the jigsaw to carefully cut along the inside rim.
Clean up the edge with sand drum on a drill or dremel, or an angle grinder .

Repeat with the second barrel. 
Sorry for the lack of picture on this step, I did this some time ago.

Next do the same to the bottom.  Be sure to leave about 1" around the edge to bolt together. 
I used a screw and a sting  as a compass from center. 
Sand these edges very well so kids don't get scratched.

Step 2: Barrel Attachment

by evenly spacing them but figured out fast that the bottoms are not evenly flat due to hand indentations.  So I had to get a few to line up first. 
Now the fun part, (hope your not claustrophobic) Crawl in and and bolt those holes together .
 Then drill and bolt the rest of the holes.

Step 3: Mounting

You will have to adjust the placement of your towers to fit the length of the barrels.
Next build a truss to hang it on.  I went heavy duty with double 2x6 laminated with hangers to double 2x6 headers.  I also boxed in both ends of the barrel end and lag bolted them to the tower.  I used a spare swing to add support to the center. 

I've had large kids in it without even bending. 
Enjoy!!