Quote:
Originally Posted by Ambient
This may be a dumb question, but can the Victory or Sherpa racks take the weight of a person?
The reason I ask is because I would like to set up my tripod on top of my 4runner and do some photography. Just want to be sure that it could take the "point load" weight.
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You'd want to distribute the load across multiple cross members. I would not be really concerned about the cross members carrying the weight. Some back of the napkin calculations: The cross member profiles are 1x2" extruded aluminum about 47" long (on my 4th gen) If you weigh 200 lbs and stand in the center of the member it would be expected to deflect a bit more than 1/3" down. (not accounting for any deflection of the side panels that are supporting the ends.)
Each cross member is connected by 2 Stainless Steel 1/4x20 bolts at each end. The shoulder of the profile would take out much of the leverage by the 1/3" deflection caused by the center load. So your 200 lbs on just one member would be focused primarily on the shank and heads of these bolts. Looking up a grade 5 1/4x20 bolt would report a clamping force of 1117lbs over a clamping area of 0.0318 Sq Inches. 200lbs spread evenly across the 4 bolts works out to each bolt supporting ~50lbs + 1/4 the 1 lb weight of the cross member itself.
The next item down is the mounting points on you're 4Runner's roof which I don't have specific details for other than the original rack's load rating of 150 lbs. But that was likely due to all of the fiberglass/GRP in the stock rack rather than the mounting point failure load.
TLDR: you probably don't want to focus all of your weight on just 1 or 2 cross members but otherwise I think the Sherpa rack can take the point load of a 200lb person standing on top.
The Owners and Engineers from
@
SherpaEquipmentCo
are members here and could weigh in with more technical details or point out where my calculations are wrong.
Boort