Propane tank holder tray

Metal and I don't get along :-(

When the weight distribution hitch was added, the tray that holds the tanks was re-mounted by the selling dealer.  3 of the 4 bolts that secure it have since broken, leaving a flimsy single bolt holding the entire 80 pounds of tray and 2 full tanks.

What is the proper fastener and method to secure this tray to the steel frame?  Home Depot wasn't any help, they only have sheet metal screws.  When I last tackled the tongue jack, the hardware store guy sold me a lag bolt, which broke again when I tightened it down.

The trailer frame is 2" x 5".  I'm considering a single 6 inch bolt through the entire mess, or trying to find a U-bolt of appropriate dimensions to secure it through the 2 slots on either side.

I'd like to fix this before our next outing Friday 8/24, but am not sure which way to go.

Dan

If it were me, I would use self-tapping stainless screws.  Use one that is slightly larger than the diameter of the current hole and approximately one-half inch long.  Four should be more than edequate.  

You could use two 1/2 inch X 6 1/2 inch carriage bolts,  but I do not think it necessary.  

Try the self-tapping screws.

Ed

...use self-tapping stainless screws...
Dan, I think you'd find self-tapping screws difficult to use as the frame and tongue are hardened steel.  IMHO you'd be better off taking the time to drill through the tongue and propane pan and fasten with 1/4" hex head bolts with a lock washer between the nut and frame.  For extra measure, ask your hardware store for "stop nuts".  They have nylon in them to help prevent them from turning (that is what I used to help solve the problem with the toilet nuts from loosening).

If you have a local machine shop, you might ask them to weld the tray to the trailer frame.  Should be easy for them and cheap.

On our trailer, which has a modified (removable) tongue, the tray holding the propane tanks is welded to the fixed (undetached) portion of the tongue.

Jon

When the dealer remounted the tank tray, did he drill mounting holes through the 2" X 5" rectangular tubes of the frame? I am not familiar with the way in which the factory attaches the tray to the frame in the TM 3023. Holes drilled through the tops or sides of the rectangular tubes may not be the best method of attachment, however, since all such holes may permit water to enter the interior of the tubes. In time this interior moisture will cause rust damage to the wall(s) of the tubes, and, might result in failure of the frame. Also holes drilled through the tops and bottoms of the 2" X 5" tubes reduce their load carrying capacity since the top carries a significant part of the compression forces and the bottom carries a significant part of the tension forces exerted on each frame member. If lag bolts or sheet metal screws were used to attach the tray, you should realize that these kinds of fasteners are not high strength ones. If you do end up using machine bolts to fasten the tray to the frame, you should purchase Grade 8 bolts. These are high-strength, alloy steel bolts that are about 90 to 100% stronger than the ordinary, Grade 2, steel bolts. Stainless steel fasteners of all kinds should be used only in locations where corrosion resistance or the stainless appearance are important. They should not be used in locations where strength is important - because stainless alloys are weaker than ordinary, mild steel alloys.

I would go along with the suggestion made earlier to weld the tray to the frame members. Welding will eliminate the necessity of putting any holes in the frame. It  is very simple to do and will provide an extremely strong connection. Since homeshop MIG welding units are so common these days, one of your neighbors might be able to weld on the tray for you. If you remove the tanks and clean off the areas to be welded down to bright metal, it should take a welder no longer than 10 minutes to weld it.

One final thing you should evaluate is whether or not there is excessive movement between the two frame members. If the two longitudinal frame members are not firmly welded to each other, the movement within the frame while the trailer is bouncing on the highways will, in time, destroy any fastener. It's also a dangerous situation. :

Regarding the movement between members, I'm more inclined to think that the chincy screws chosen were the problem.

Right now I'm using 2 bungee cords.

Some friends at work directed me to an auto spring shop.  Over the phone, they indicated that they could bend threaded rod to my specifications.  I'm going to go over the frame, through the 2 slots on each side of the tray.

Incidentally, I noticed that's the same way the spare tire holder is attached to the rear bumper.

I had custom U-bolts made at the auto spring shop: 2-1/4 in. x 6 in.  Cost was <$11 for both.  They fit aound the frame and go through the pair of openings on either side of the tray.  This gives a very tight, secure fit.

They only interference is where the sway control was mounted to the frame.  Since I destroyed it by turning too sharply on my last trip, I'll worry about that later.