Custom underbody boxes


I am looking to have some custom underbody boxes made or make them. I have seen some of the trucks have boxes that are made from something that is not aluminum or steel. What materials are these boxes made of? Anything on the Internet on how they are constructed? Thanks


I have seen some fiberglass boxes but have no idea who makes them. Perhaps someone that fabricates custom marine stuff could do it. Let us know what you find!

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Everything on an expedition truck build has to be custom build. You will need to speak to a local fabricator. I prefer guys that can CAD draw everyting up to be sent for laser cutting and bending. It is the only way you get a high quality finish. Hand made stuff always looks hand made.


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I would argue that the owner of the hands is the one that dictates how good it looks...
I have seen many things that are hand made that are nothing short of brilliant.
I agree but the hands that can measure and cut a to 1/64" are on the list of endangered species as are those that know what it is and are willing to pay for it.
I would argue that the owner of the hands is the one that dictates how good it looks...
I have seen many things that are hand made that are nothing short of brilliant.
Hi SkiFreak

There is merit in your defense. There is always the exception but like Alloy rightfully posts above it is a rare and dying skill.

So unless you are fortuanate to be the man with that skill, or to know the man (which after years of commissioning literally several hundred thousands of dollars of custom fabrication work I have yet to meet); I choose to pay the money the first time around every time.

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it seems Owen (SkiFreak) has skills which others may not imagine. A perfectionist. Meticulous. A jig for everything. Fine Engineering Tolerances. Pride. I know we are having an election in Aus but fortunately Owen isn't a candidate. I was going to say never makes a mistake but that would be one superlative too far.

For my part, if I can't find someone to perform a task to my expectations I look elsewhere or do it myself. Not sure where 1/64" came from as being acceptable, half a mm is a lot. I'm not a fitter, nor do I have Owen's skills, but I can file something flat and square to less than 1/1000". I was taught so I could appreciate the skills of those who followed a career making and maintaining things. Access to a reasonable workshop helps - my lathe is getting a bit tired.

The simple reason for tight engineering tolerances (as different perhaps to building tolerances) is it makes design easier, things fit without rework, build time is less (though Owen may disagree on time for a part at least final assembly is order of magnitude shorter), longer life, maintenance is easier and less time to repair.

The consumer world is very different to the heavy industries I worked in. Most of what we buy for our trucks is consumer grade, built to a price not a quality. With specs and quality that owe more to marketing than engineering.

I learned a new textonym a few days ago which seems relevant ............ ymmv ........... Owen's post wasn't a defence, it was simply a statement.


Well for the extra money I will be paying for will be for a team of experienced some with many years computer design. Quality work. Best materials best fit. And since the last 5 months of travel in Mexico with some of the worst roads I have driven on. I am talking highways. (Although they have many good roads.) quality heavy duty stuff is required!!


We took our little Fuso to the doctor today. Improved the rear suspension...again. And took the balancing beads out of the fronts and replaced with lead again. All done by excellent workers in Mexico.

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Gotta Be Nuts
Ok, I'll first admit that I am new to trucks like these (we have a MB 1120AF that we are currently building), though I come from a long distance sailing background (lots of custom stainless, never laser cut). The original post was asking about under habitat storage boxes, do you guys really feel these need to be laser cut and bent to fine tolerances? In about a month I had planned on starting in on the exterior metal work and have lined up a welder that usually fabricates stainless on custom yachts (I checked out the $2.8 million dollar ketch he had done the work on). Standing there his work looked like objects of art. I feel pretty confident that if he built boxes/tire rack/roof rack that they would look professional and be durable.