Is that Tiedown strong enough?

[Ryanmb21]

.....

But then I was thinking about wood construction, and tee-nuts, and tear out, and how would one go about building a wooden drawer system that would stay together in an accident? Mechanical fasteners in wood are interesting, because a number of factors are in play, including the wood, whether the wood is solid or otherwise, the orientation of the wood to the joint (i.e., lap, butt, rabbet, scarf, etc.), and the type of fastener; screw, bolt, adhesive, or other. Lots of alternatives, yes?

For fastening with screws, here is an interesting paper: http://www.fpl.fs.fed.us/documnts/fplgtr/fplgtr113/ch07.pdf Once again, lengthy. This chart is easier to read: http://www.screwdoctor.com/application/home/selection_guide/technical_data.aspx Keep in mind that the question we are considering includes both tensile (tearing apart) and shear (breaking the long axis of the fastener) components.

What happens when you add an adhesive to a wood (or any other) joint? It generally gets stronger, and the joint is better able to withstand both types of forces (greater shear and tensile strength). There are many, many articles available on this, for example, https://www.freemansupply.com/datasheets/adhesivesguide.pdf provides an overview or introduction. From there, the possibilities abound.

After thinking about it, I think I will likely build my boxes out of plywood using mechanical fasteners, and reinforce the joints with something akin to a fiberglass tape. Fastening the boxes to the vehicle will be via grade 8 fasteners through bolted through the vehicle's floor, with appropriate grade 8 backing plates, properly torqued. And a net between the passengers and the load. And the rest I will leave to chance.

@DanCooper - thanks for the links, I will spend some time with them. I was on a similar thought process of how to build wood drawers, the crux came with how would I mount fridge to the top of them? The considerations you list are appropriate. I also like the idea of using some sort of fiberglass. At this point I'm sort of leaning of just staying with what I have even though I am curious to try drawers.

Curious to hear more thoughts - thanks!

 

[volkinator]

Not sure about your needs, but for me, a barrier isn't an option. I do agree with overbuilding, but within reason. I'd look at the factory tie-downs and do my best to replicate that. (I think most of them are just a weld nut on the underside of the body) If you're concerned about a bolt and washer ripping through 3/4" plywood, you're probably packing too much, or not securing it well enough. Minimizing movement is key. Static load will be much less than a dynamic force in an accident. If you can do things like tie down cooler/fridge using turnbuckles or ratchet straps to make it tight, you shouldn't have any problems. As you're tightening it, check out your tie down... did it move or deform? If not, I don't think you'll have a problem. Yes, use correct hardware. Grade 8 is obviously suggested whenever possible. But I think the key is that you're tying it down period. There are so many people that don't understand projectiles and how vulnerable our heads are.

If you're building drawers, keep the smaller things inside and out of the way so they are contained. Strap down what you can, and light fluffy things on top.

My $0.02