I am putting together a small trailer to be towed behind a mtn bike. I will carry 2 kayaks (about 80 lbs) and paddles on a cinder rail bed ( out by ohiopyle pa) I am using 1 inch square aluminum tube that is bent and braced with 1/8″ thick Al flat stock. I have secured the braces with 5/16th long 3/16 diameter rivets, and I am now wondering if I should also through bolt my cross braces. (I did fillet the braces with JB Weld too….
Replies
pure shear in alumunum...
bolts are better... use SS..
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
BTW.. don't build too rigid.. you'll want some flex....
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming
WOW!!! What a Ride!
Forget the primal scream, just ROAR!!!
My suggestion is you take whatever you thing the actual load might be on any shear connection - say 100 lbs for example - and multiply it by 10.
In this example the 100 pound load might actually be 1000 at any given point, if you consider bumps WITH acceleration WITH drag.
Here is how you make a controled 1000 lbs force on a riveted connection. Get a 20 lbs weight. Get a metal bar 50 inches long. Rivet at 1 inch to a stationary piece of metal. With the end closest to the rivet stabilized on a ledge, hang the 20 lb weight at the other end of the 50 inch long bar. In this case:
Applied Force = (Weight x distance from pivot weight is applied) / distance from pivot that force is applied
so
1000 = (20 x 50) / 1
If your rivet shears off there (or wherever you calculate) you may want to reconsider your choice of fasteners.
This safety ratio for live loads was what I was taught many years ago in building sets. If you build something to carry a dead weight, built it to carry twice the weight. If you build it to carry a person, built it to 10 times the person (and whatever they are carrying) weight. When a person jumps, they can deliver ALOT more force than they apply standing still.
Rebuilding my home in Cypress, CA
Also a CRX fanatic!
Well, airplanes are put together with rivets, but the rivets are speced for the job. It all depends on the rivets.
skyscrapers are tied together with riviets too, but I would not trust any load to an AL rivet. They are OK for gutters to make the joint is about all, IMO
Welcome to the Taunton University of Knowledge FHB Campus at Breaktime. where ... Excellence is its own reward!
not any more....
proven to fail...
Life is not a journey to the grave with the intention of arriving safely in a pretty and well preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming<!----><!----><!---->
WOW!!! What a Ride!<!----><!---->
Forget the primal scream, just ROAR!!!
You need to tell us what the alloy of the Al tubing and brackets are, and what the rivet alloy is. If you 'bent' the Al tubing, it is likely 6061-0 or T3 at the best, doubtful for use on a trailer that would be subject to fatigue, shock loads, etc.
As already implied in previous posts, Al rivet specs range from soft to better than mild steel. If Home Depot or Harbor Freight pop rivets (or very soft Al), drill them out and put in a couple of 1/4" bolts - plated mild steel OK for your low loads.
A 2x proof load on the entire trailer may be in order like suggested, esp. if soft Al tubing was used.
Ahhh... the rivets are spaced so that it will be real easy to leave them in place and through bolt too.. I thought ahead on that one!