I get these ideas sometimes and for better or worse I follow through. Even though I have been using a perfectly good Thule rack system ( the type that has pads that sit of the roof top and hold down clamps that grip that black rail thing I installed for the purpose), the airfoil section aluminum spar material that was lying around the shop was too tempting.
Here’s the old Thule rack.
It’s the type of spar material you see used as spreaders on sail boats. This version is pretty stout, 1.5″ at thickest and a chord length of 5.5″.
The idea was to have two racks and not have them wider than the pop top. And the Thule ski box I use would be attached directly to the rack, not using the stock U bolt set up.
I cut the spars to 53″, and cut some shorties to act as pedestals. I coped the short bits to fit the airfoil section and welds them to the cross pieces. I also cut out some 1/8″ aluminum sheet and used that to close up the ends. This pic shows one with end closed, the other still open. You can see the slightly thicker section of the spar in the open end. All my attachments go to that thick section.
That groove running along the lenght of the spar falls pretty well on the middle of the thick section. On one end of the soars I drilled and helicoiled holes for the Thule box attachment. On the other side I used some 5/16″ riv-nuts as anchor points for eye bolts in case I need lash points for some future thing. Blanked those holes off with plain bolts for the time being.
And this is how they sit on the van.
The hold down mechanism took me a while and I ended up with a simple, if a little clunky, solution. For now the stainless brackets hook onto the rail, but when I am happy with the position of the racks I’ll bolt them to the rail and cut off the hook end. It’s a 5/16″ bolt attaching the bracket to the spar (helicoil in spar), I know it looks sort of week, I think it’s strong enough. It certainly pulls the rack down hard to the roof. Later you’ll see that I put in short sections of rubber hose to cover the naked bolts and make that part look less flimsy.
I am planning on painting the rack white, same interlux briteside one part polyurethane I used on the pop top itself. When it’s painted I think the rack will blend in with the roof, take away the raw industrial look.
It’s funny, the box still looks like it tilts towards the centre of the van. The cross spars are level, maybe the box itself is warped.