16 replies to this topic

[No longer here]

I do love the rack though. Adding traction mats, fuel tanks and an axe back there make it less of a old man RV and more adventurmobile At 40 though....i'm quickly hitting old man status lol

[rando]

Agreed, the brackets are surely strong enough for this.   You would want to mount the gas cans at the ends to minimize the deflection in the cross bars, and use larger T-slot, either 1"x2" or 1.5"x3":

https://8020.net/1020.html

https://8020.net/1530.html

 

Is there anywhere else you can mount at least the gas cans?  With two full cans, and mounts, 4 traction boards and the rack necessary to hold all that weight you could end up with 200 lbs way behind the rear axel and up high, which is precisely where you don't want it. 

 

I worked hard to avoid this and mounted 6 gallons of gas down low and in front of the axel under the flatbed, not a great photo but visible:

 

[rando]

Also the T-Slot profiles  and everything else you could possibly need are also available at McMaster Carr, which has an easier to use website and uncanny fast shipping - like order by 5pm and have it arrive by 10 am the next day (that is less than 18 hours).

 

https://www.mcmaster...slotted-framing

[No longer here]

I used the 40 series T-slot with very little defelection. I agree that 6 gallons up high is a problem, but 6 gallons is 36 lbs. Also not carried 100% of the time. Reasons like this is why the steel rack is not good for this application. Mcmaster is nice, but don't offer custom that I could see, nor is it threaded. Still a great option!

[kmacafee]

I looked at T-slot but am/was concerned that the slim head of that t-bolt was carrying a fair amount of weight, especially if the vehicle is traveling on uneven surfaces.  An engineer suggested using square aluminum stock instead and bolting everything through that. Obviously, its not as versatile and adaptable as T-slot but based on what I have read, much stronger.  I'd love to hear how it holds up.

[rando]

The T-slotted profiles are pretty impressively strong.  We have used this to built instrument racks for research aircraft which require structural analysis, and if memory serves me correctly the 15 series stuff we were using was rated at something like 2kN per fastener - which is around 500lbs.    It would take some extremely high G-forces to reach those limits,  especially if using multiple fasteners for heavier loads like gas tanks. 

[Hoopy]

there is such a markup on those racks with a little thought one can save lots of $.  I welded up one outa aluminum have our trash bag on it for now.  plenty of room to add things if we want to. I guess I use it to pull up and release the back clasps on the roof makes a handhold for that!!