Crate middle rail

[ThunderPorpoise]

We are getting our crate together here and after putting the two 4x4 forklift runners in we noticed that the bottom was a little saggy, so we through a center runner between everything. Is this acceptable? The distance between the two outer runners is still 30" but the distance between the outside and middle is only 13.5". Will we have to remove this center rail?

http://imgur.com/IlTekPc

[GreyingJay]

What if you reinforce the bottom panel with extra runners on the inside of the crate instead? That's what we did.

[MrForbes]

We put some 2x4s on top of the bottom sheet of plywood, perpendicular to the 4x4 skids, so the robot chassis rests on the 2x4s, instead of the wheels. This makes the bottom of the crate pretty strong, too.

[GreyingJay]

Yes, to be more specific, that's what we did too.

Since our existing crate was 70" tall and all the official documentation strongly advised international shipping crates be no more than 60" tall, we also used 2x4s to frame around our entire robot and affix it to the 2x4s along the bottom of the crate, so that in case they shipped our crate sideways, nothing would move.

[FrankJ]

The point of the 4x4s is to allow the crate to be handled with fork lifts & pallet jacks. Having a center rail generally is not an issue. Most pallets have a center support.

[GeeTwo]

We put some 2x4s on top of the bottom sheet of plywood, perpendicular to the 4x4 skids, so the robot chassis rests on the 2x4s, instead of the wheels. This makes the bottom of the crate pretty strong, too.

We did the same. Using a house analogy, put the heavy items on joists, not the subfloor. The plywood/CDX should serve mostly to keep out the weather, not to provide support. The same should be true for the sides/top - hold the robot in place with a timber frame, and use the plywood for sheathing.