Mounting something to the top of a truck tool box

[CLynn85]

Ok, I'm just looking for others' experiences here.

The situation: I want to install a yakima blockhead fork mount on my UWS tool box for expedient mountain bike hauling in the bed of my truck w/out dealing with racks and ish.

The problem: I'm lacking about 1.5" in length to be able to put it on the rear face of the tool box. I tried an L-bracket on the lip of the lid so as not to go through the top of the lid but it's too flimsy.

The question: If I bite the bullet and drill 2 holes in the top of the lid and goop the living @#$^ out of them with silicone, will I still have water leaking into my tool box?

To further complicate matters the UWS box has a two-layer lid with foam in between.

 

[4x4x4doors]

Some thoughts:
1. Why does the bike have to be parallel to the side and centerline of the truck? Is there a reason that the bike couldn't be secured with the front fork on the box and then turned a few degrees to make the whole thing fit with the tailgate up?
2. Epoxy the mount to the lid without drilling holes.
3. If one can drill through a roof (vehicle or shell) and people do, there wouldn't seem to be a logical reason you couldn't also seal the connection with the tool box lid.

 

[BigAl]

I'm guessing your tool box is aluminum diamond plate. The diamond plate ridges may cause you a little grief with getting a good seal but with silicon, I'd do it. Alternatively, isn't the yakima mount aluminum too? You could have a shop weld it on.

 

[CLynn85]

I'm guessing your tool box is aluminum diamond plate. The diamond plate ridges may cause you a little grief with getting a good seal but with silicon, I'd do it. Alternatively, isn't the yakima mount aluminum too? You could have a shop weld it on.

It is diamond plate, which is a large part of my concern. I actually considered welding a boss to the top of the tool box with threaded holes but the uws boxes have a 2-layer lid with foam in the middle, which I was worried about getting hot and burning up, not that there'd really be any consequences I guess...

 

[red87]

I'd just drill it and use some 3M Marine sealant 5200. That stuff is designed to work underwater so it'll do a grand job of sealing out rain. Just be careful to not crush the lid when you tighten the nuts. It may even behoove you to sleeve the holes so you can't crush it. Just use some steel spacers slightly shorter than the thickness of the lid so you can still get things nice and tight.

 

[xdbx]

I'd drill holes in. Then use some wide fender washers along with a pair of rubber washers of equal size and a round head bolt coming up, or threaded rod if you like with a nut (nuts) compressing the connection. You'll be able to compress the rubber and seal much better than just air cured silicone. If you see leaks down the line, silicone down, then thread together. I'd also trust my $$$ mountain bikes on a sturdy mount like that, and potentially more secure than the above mentioned with the use of acorn nuts or similar.

 

[soonenough]

It may even behoove you to sleeve the holes so you can't crush it. Just use some steel spacers slightly shorter than the thickness of the lid so you can still get things nice and tight.

x2, that's a great idea. This is your safest bet for not crushing the lid. For getting the holes sealed up, another idea is to pot the area around the holes with a UV-stable epoxy. Only do this if you're positive you don't want to remove everything later on, as epoxy will be really tough to remove.

EDIT: on second thought, I don't know how well the epoxy will hold up to the thermal expansion and contraction of the metal with temperature, so maybe a sealant would work better.

 

[CYi5]

Do it, i had my shovel mounted with quick fists on my old tool box. Never sealed it now that i think about it and had no issues. I used screws instead of bolts though, probably makes a tighter seal.

 

[trailrunner]

If your worried about not getting a flat seal with the diamond plate, 2 minutes with a grinder removing the ridges would solve your problems regarding the uneven surface.

 

[Krouoffroad]

I would use some "Nutserts" they do require a special tool to install them but i use mine more than a rivet gun now. Put those in and add some 5200 to your bolts. Ive done this several times for several different things and havent had a leak yet. You dont have to worry about crushing the lid,leaks, and they have held up GREAT for me.

Typically the Nutserts range in size from a #6 machine screw to 1/4x20. But I have found some called "Plus nuts" that are 5/16's they are a little different to install but offer alot better hold. You can still install them blind like the nutserts but they require a 1/2 in hole drilled and you need atleast 1" behind your surface for the insert to seat before you can compress it. Whenever I buy a bag of the plusnuts they come with a aplication tool which consists of a special looking nut and a long bolt. The nutsert tool works on the same concept of a rivet gun.

 

[southpier]

...some called "Plus nuts" that are 5/16's they are a little different to install but offer alot better hold. ...

this is what holds my toolbox to the bed; works great and was a "1 man operation"