T Track fittings for Roof Box

[stroller133]

Hi

I have bought separately a used set of Genuine GM roof bars for my 59 reg Astra Estate and a used Halfords Roof Box.

The roof box came with u bolts to fix to the roof bars, but being aero type bars the u bolts do not fit around the bars. I went and bought a Thule fitting kit to use the T rail on the Aero bars instead. I tried to fix it this afternoon and found that the T bolts slot into the T track ok, but for inside the roof box they supply a block, with a pring to fill the second hole for the U bolt fixings. However I found that the kit is 80mm, but my u bolts must be about 75 as the prong is not quite in the right place to plug into the hole.

I have 2 ideas to get around this:

1. Don't bother with the block and just tighten the butterfly nut against the floor of the box. I would then need a bung or tape to cover the other set of holes. Concerned that this might be too tight on one spot and risk cracking box.
2. Use the block to spread the load, but cut of the prong off, otherwise it won't sit on the floor straight as it it. This will sort of cover the hole, but might still use a bung or tape on the outside to make sure.

Does anyone have any advice on which would be better, or have any other ideas?

Thanks

 

[Crickleymal]

Why not just drill a hole for the prong rather than cut it off? I imagine it's there a, to plug a hole and b, to stop the block rotating when you tighten the bolt or something.

 

[stroller133]

Thanks for advice. I got there in the end on my own - I did drill new holes for the block to locote into. I though I might want to use the T Track fittings if I buy a new box later in the year so thought it was better to leave them intact. The existing holes are still covered up by the block.