General Instructions for “KidWind Light” wind tunnel.

It should be noted that what you are assembling is a prototype tunnel best described as a “proof of concept”. It has some irregularities that have caused it to have a front, back, left and right side. It does matter which way the fabric faces, because the upholstery shop had a bit of a rough time sewing the fabric to the clear vinyl, thus the spacing on the ribs was not held to 14” on center, therefore I had to drill new side rails to accommodate the irregular spacing of the support ribs. Also, the wooden rails were originally designed for use with 16” fans, not the 20” fans we’re using. They’ve been spaced apart with metal brackets to widen the footprint of the tunnel - which helped with the placement of the fans at the front of the tunnel (by opening up a space for the inner feet of the fan packs to protrude through), and allowed us to bring the fans closer to the tunnel, thereby also allowing the outer fan pack feet to mount directly to the side rails, which helped with consistent placement and stability. During extended assembly, I noticed that tension from the tent poles was bowing the metal on the back end, causing the tunnel to lay less flat. You may wish to add another cross or bottom bracket. The PEX tubing used for the center 3 ribs provides a nice circular shape for the tunnel in the test area of the spinning blades of a horizontal shaft turbine. The tent poles used for the ribs on each end provide much improved front to back stability, assisted by a top mounted spacing pole. This tunnel has worked well for us in competition, but we’d appreciate any feedback you can supply, to help us better refine it before offering kits. THANKS!

Switch inner and outer nuts so the locking style “nylock” nuts are on the inside, before mounting side rails. You may make use of the plain nuts for mounting the side rails, or you may perhaps choose to substitute wingnuts. The nuts and bolts provided are metric - 8mm with a 1.25mm thread pitch. Note: Of the 4 fans that I took apart I noticed wild inconsistencies in the wrench size needed to remove and install the standard nuts. Some nuts required a ½” wrench, others 9/16” and others still were in between at 13mm. You may wish to replace these with 8 nuts that all take the same sized wrench. Note: The side rails are drilled to allow for different sized fans, but I mounted these fans using the inner most holes and made small brackets to bridge between each fan. If you choose to mount the fans farther apart, you will need to make your own bridge brackets.

Note: Bridge brackets between fans are designed to stabilize the fan sets and fit if you use the “King of Fans” fan model that KidWind sent… AND you are mounting the fan side rails using the inner most holes on the rails. (23 inches apart on center) If you are using other fans, or mounting the fans farther apart on the rails, you’ll need to fabricate a different set of bridge brackets. Remove screws from fan housing cover and replace with the longer screws I provided with the bridge brackets.

The PVC legs are drilled to attach to the fans original stand brackets, but I recommend removing the factory machine screws, and instead using the longer sheet metal screws that I’ve provided.

Notice “FL” markings (front left) on side rail and base. Each corner has similar markings Also notice the wood is cut down on the front pieces to allow the fans to clear. Each corner is pinned with short aluminum pipes, also providing a more stable mount for the tent poles at each end of the tunnel.

Fans attach to tunnel base rails to stabilize the fan packs.

The “front” of the fabric needs to be on the same end of the tunnel as the fans. The spacer rod fits through slots in the fabric and cradles the tent poles to help keep the tunnel taut and stable. The rod will have a slight bow shape, with the arch reaching up in the middle.

Duct tape on side rails marks distance from fans where air moves at 5 m/s. Single collar controlled depth of PEX tubing in side rail during early construction.

The inside feet of the fan packs protrude between the wooden rails.

Notice that the fan backs have been rotated so their cords exit to the outside. Unscrew the front cover and rotate 180° to keep logo on the fan front - right side up.