Cullman Derby Ramp - Part 3 - Support Structure

 With the ramp profile set, the next task was how to piece it together. The main criteria being:

• Safe and maintain functionality
• Easy for anyone to assemble
• Able to disassemble for moving and storage
• Keep weight low so parts can be moved by hand

The 4' wide plywood ramp would need intermediate support and a starting mechanism on the centerline, so (4) sloped beams would be needed on each ramp. A transverse beam at the top and a board to keep the upper and lower sheets of plywood aligned complete the ramp. Because the curved portion is so thin, it would be impossible to build it as curved glulam - so it is actually made as a separate straight piece of glulam cut to the curved profile.

Glulam members forming the ramp

Supporting that ramp we wanted to make as simple as possible... easy to assemble, stable, and hold the ramps together. This consisted of two support beams connected together.

Ramp with support beams

Both of the blue beams have notches for the ramp to fit into. The shorter of the blue beams is a single, continuous member supporting both ramps. The yellow beam connects the short and tall blue beams. The taller blue beam is quite large, so are separate for each ramp to keep the individual part weight down.

Because these ramps would be assembled and disassembled multiple times, we developed a new connection detail for attaching the ramp to the support frame with just (4) bolts per ramp:

Bracket on support beams for simple bolted ramp connection

That's the ramp structure complete, which was only a little outside the comfort zone of what we normally work on. (Nothing should move once it is put together.) But these ramps will require a starting mechanism... more on that next time.