Home made cross bars for factory Trail roof rack

[High_Country]

I have done some searching with not much luck. I am interested in designing/fabricating my own cross bars / rack to attach to the FACTORY rails on my 2014 Trail. In concept, it will be very similar to the Rocky Road Outfitters design:
4runner Roof Rack:Â*5th Gen 4Runner Roof Rack

I like this rack, and it's affordable enough, but I have some decent design and fab skills, a welder, etc and I would like to make a few changes / improvements for my personal use.

My MAIN QUESTION is how the Rocky Road rack (or the factory cross bars) interfaces and locks into the existing rails. There's not any good pictures of it on the RR website but, here's a couple:

I haven't been able to find Toyota OEM cross bars to look at the ends either.

Is it a simple "friction" fit where you tighten the rack down against a backing plate that locks the cross bars in? Is it a ratcheted or toothed system?

Any insight, pics, or explanation is appreciated.

 

[BettysNephew]

Tee slot nuts would cinch everything down quite well. Ask at your local big box home improvement store.

 

[High_Country]

That's a good idea. A quick google for a pic:

So, you're saying it's a simple friction fit that holds it all in place or said another way, 'clamping' to the factory roof rails. If it's that simple, that's awesome.

 

[KodeRush]

Some carriage bolt like this served me well:
Crown Bolt 3/8 in. - 16 tpi x 1-1/2 in. Zinc-Plated Coarse Thread Carriage Bolt-800236 - The Home Depot

You can also get stainless steel version.

 

[bpwwer]

Look in the for sale/wanted post here for a picture of the factory crossbar ends:

http://www.toyota-4runner.org/5th-gen-t4rs/80618-5th-gen-sale-wanted-thread-290.html#post1987416

 

[High_Country]

Some carriage bolt like this served me well:
Crown Bolt 3/8 in. - 16 tpi x 1-1/2 in. Zinc-Plated Coarse Thread Carriage Bolt-800236 - The Home Depot

You can also get stainless steel version.

Thanks for that. I got to thinking more about the t-slot nuts and I'm not sure they would do the trick as the 'table' or part that sticks out might stick out too far not allowing the rack to clamp to the rail.

I was thinking maybe a nut with a large shoulder or heavy washer tacked on would slip into the rail. But, a simple carriage nut (with the head on the inside) would work just as well I think.

 

[DesertCanyons]

... I am interested in designing/fabricating my own cross bars / rack to attach to the FACTORY rails on my 2014 Trail. In concept, it will be very similar to the Rocky Road Outfitters design:
4runner Roof Rack:Â*5th Gen 4Runner Roof Rack

... My MAIN QUESTION is how the Rocky Road rack (or the factory cross bars) interfaces and locks into the existing rails. There's not any good pictures of it on the RR website but, here's a couple:

... Is it a simple "friction" fit where you tighten the rack down against a backing plate that locks the cross bars in? Is it a ratcheted or toothed system?

Any insight, pics, or explanation is appreciated.

Betty's Nephew makes a good point. Unistrut makes metal support systems for the construction industry and industrial applications. Unistrut also makes a T-nut that would fit. If you can find a supplier who sells Unistrut retail, look in their catalog.

I looked at this rack too. It's simple and fits close to the roof using the original roof rack rails. It may be stronger than some of the racks that replace the rail with a support bracket. I couldn't figure out how it attaches either. That's probably a well-guarded trade secret. It probably uses friction to resist fore and aft movement but not upward pull or downward gravity. I think you're right, there's a plate with bolts attached that may slid into the rack from the rear by removing the back cover end of the original rails.

I'd like to have this rack with more cross bars so I can tie down smaller items and stand on the roof. I often like to get up there to shoot photos from a higher vantage point. They offer lots of different racks. I may call them and see if they'll add some cross bars or an extruded steel fabric floor. I'd consider making it even lower, closer to the roof too.

I don't like how everything requires bolt heads and U-bolts that stick up on top of the rack. The could have designed the bracket at the main tube brackets to turn the bolt heads sideways.

 

[BettysNephew]

[MENTION=115572]DesertCanyons[/MENTION] thanks for jogging my memory.

I used the wrong name for the nuts I am referring to. Try channel nut instead of T-slot. They go into the open slot of the channel and when you turn the bolt the "wings" turn and snug up against the back side of the channel. Sorry about that. Google channel nut and there are pictures of what I was trying to describe.

 

[BettysNephew]

FWIW, My local Home Depot and Menard's have channel nuts in stock. Lowes turned up zilch on a search.

 

[High_Country]

Right on. The channel nuts look to be the ticket. They'll hold against the rails for tightening while providing a good amount of surface area for clamping and frictional resistance. Thanks all.

I'm working on a sketch up model of my concept and hope to post something soon for constructive criticism.

 

[96r50]

Here are a number of potential options.