This is non-RV, but it is metal fabication kinda. I have used just sheet metal screws to hold in my truck tool box by screwing the back into my truck bed up against the cab, but the sheet metal screws pull out after not very long. Is there anything out there similar to a hollow wall anchor for metal? Maybe even a butterfly nut that could hold it more securely than depending on just the screw threads. Thanks in advance.
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General Metal Work Tips - Tool Box
- Thread starter Brian130
- Start date
ddurakovich
Well Known Member
Brian130 said:
A Rivnut comes to mind, and can be done "blind", I'm just not sure it will give you enough surface area to spread the load out.
Take a look at:
http://www.aircraftspruce.com/catalog/hapages/rivnuts.php
THere is also a relatively cheap tool for installing these using a standard "pop rivet" gun, but I've had mixed results with it....
Good Luck,
Dave
This seems very obvious to me.
Stay away from sheet metal screws entirely. I mean, you probably have 100 lbs. of tools and junk in the box, plus the weight of the box, and you're asking a few screw threads in thin sheet metal to support it?
Use nuts, bolts and big fender washers at a minimum. If you really want to do it right, make a doubler plate to spread the load... but stick with the nuts and bolts. Use red Loctite if you never want it to come apart (plan on leaving the toolbox in the truck when you sell it) or blue Loctite if you just want a little peace of mind. Or use drilled bolts, castellated nuts and cotter pins if you want positive locking on the bolts and want to get them off someday.
Stay away from sheet metal screws entirely. I mean, you probably have 100 lbs. of tools and junk in the box, plus the weight of the box, and you're asking a few screw threads in thin sheet metal to support it?
Use nuts, bolts and big fender washers at a minimum. If you really want to do it right, make a doubler plate to spread the load... but stick with the nuts and bolts. Use red Loctite if you never want it to come apart (plan on leaving the toolbox in the truck when you sell it) or blue Loctite if you just want a little peace of mind. Or use drilled bolts, castellated nuts and cotter pins if you want positive locking on the bolts and want to get them off someday.
I agree. That would be the very obvious answer... if I could get a nut and washer between the cab and the bed. That's why I went with just sheet metal screws in the first place. I have about 1/4" of space between the two - not enough room even for a average sized nut. I need something like the first reply with the blind rivet . Thanks for the try, though.
Brian
. Thanks for the try, though.Brian
Or...
The blind rivet/rivnut is going to pull out for the same reason the sheet metal screw did, won't it? You still need to spread the load.
I can think of two ways to get your washers/doubler installed, neither of which is pretty:
1) The bed is just a huge box bolted to the truck frame, right? So, unbolt it, shift it, install your hardware, and put it back together.
2) Go into the cab, remove the stuff against the back wall, drill holes big enough to do your installation, then permanently plug the holes.
I'd say both of those fall into the Not Worth It category.
Or....(I think you're going to like this one)...
Here's an alternative way of preventing overstress on the screws:
The reason your screws are pulling out in the first place is because the box is trying to move away from the position you've got it in, right? So...give it a way to resist that without putting a big tension load on those screws.
Use angle brackets screwed to the bed to keep the box from wanting to move. Make a frame of 1x1 alu angle or equivalent the same size as the box footprint (with the flanges outward so the box can sit flat on the truck bed) and attach the frame to the truck bed. Set the box down inside the frame. Now the box can't shift laterally anymore...in fact, you could probably drive around like that without even attaching it and it wouldn't move unless you hit a big bump. You don't even need a full frame...two "chocks" per side (front and side(s), since the back of the box is screwed to the truck cargo box sidewall) should do it.
You can use screws there because the load is in shear. Since the box is positively located, it won't be trying to pull the screws you've got going into the side of the bed out all the time. Properly prime/paint or otherwise corrosion-proof the bed floor brackets and screws to make sure they last.
The blind rivet/rivnut is going to pull out for the same reason the sheet metal screw did, won't it? You still need to spread the load.
I can think of two ways to get your washers/doubler installed, neither of which is pretty:
1) The bed is just a huge box bolted to the truck frame, right? So, unbolt it, shift it, install your hardware, and put it back together.
2) Go into the cab, remove the stuff against the back wall, drill holes big enough to do your installation, then permanently plug the holes.
I'd say both of those fall into the Not Worth It category.
Or....(I think you're going to like this one)...
Here's an alternative way of preventing overstress on the screws:
The reason your screws are pulling out in the first place is because the box is trying to move away from the position you've got it in, right? So...give it a way to resist that without putting a big tension load on those screws.
Use angle brackets screwed to the bed to keep the box from wanting to move. Make a frame of 1x1 alu angle or equivalent the same size as the box footprint (with the flanges outward so the box can sit flat on the truck bed) and attach the frame to the truck bed. Set the box down inside the frame. Now the box can't shift laterally anymore...in fact, you could probably drive around like that without even attaching it and it wouldn't move unless you hit a big bump. You don't even need a full frame...two "chocks" per side (front and side(s), since the back of the box is screwed to the truck cargo box sidewall) should do it.
You can use screws there because the load is in shear. Since the box is positively located, it won't be trying to pull the screws you've got going into the side of the bed out all the time. Properly prime/paint or otherwise corrosion-proof the bed floor brackets and screws to make sure they last.
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