DIY Sprinter Bed Platform Using Struts
I struggled with which system I was going to use to make my platform bed frame. I considered most of the “standard” materials including wood, E-Track, slotted strut channel, and the ever-trendy L-Track.
I also considered the various bed-platform kits that are available as well as a custom build by a local conversion shop, but those options were a bit out of my price range.
I did have some criteria in mind already and then developed some more as things progressed:
- Simple: no reason to make a “platform” complicated;
- Flexible: ability to alter configuration or add to it;
- Adjustable: different toys need different storage;
- Inexpensive: sorry, but I’m not paying $3k for a platform bed; and
- Strong: I do plan to use my 4×4
After pricing out the options and considering how I wanted things to work, I started down the strut path. This was partly influenced by the fact that I wanted to make something relatively quickly. Sold as UniStrut and SuperStrut, I thought it was cool that I could pick this stuff up at any local big-box hardware, plumbing, or electrical store. I was also intrigued by the ERECTOR-set (ya, that ages me) flexibility and the fact I only needed my angle-grinder with a cutting blade to make it all happen.
Another important technique to add here is the use of rivet nuts (RIVNUT (R)). I think these things are a game changer in doing this type of work. My prior van was converted (by someone else) using screws and a few bolts to connect stuff to the van. In general they worked, but they occasionally would pull-out, rust, or break off. Trusting that most professional and engineering applications that attach stuff to sheet metal use these things, it’s not really a tough choice. All you need is a rivet nut tool, a drill, and a box of rivet nuts. (There’s a bunch of online videos on how to use these things – but really, they’re pretty simple.)
Measuring
I decided that the core of the bed frame structure would be anchored to the horizontal rails just below the windows. I used some blocks and clamps to hold the strut in place while I marked the locations for the rivet nuts to align with the existing holes in the strut. Although the bed platform would be mounted in the rear, I wanted the driver’s side strut to run the length of the cargo area. This would prove to be handy for mounting cabinets and such.
Drilling
At each marked location, I drilled a 1/8″ pilot hole through the plastic trim and the sheet metal below. Before drilling, I made sure the hole locations were clear of any connecting structural members that may interfere with the rivet nut.
For the initial install I wanted to leave the plastic edging trim in place, so I used a spade-bit drill to cut a hole in the trim to accommodate the head of the rivet nut. The tip of spade bit ran in the pilot hole and I drilled just deep enough to cut out the plastic. (Note that after I was satisfied with the layout, I later trimmed the plastic around the strut so the strut was flush against the metal.)
I then enlarged the interior hole in the sheet metal to accommodate the rivet nut. I used 8mm rivet nuts for all the chassis mounting which requires an 11mm drill. You can see the resulting hole in the plastic trim. (I used masking tape to mark many of my measurements.)
After the rivet nuts were installed, I mounted the horizontal strut. Along the driver’s side I used eight locations to mount the 10′ strut (which, by the way, fit perfectly in my 144 van.)
I repeated the same process along the passenger side behind the door but only using six nut locations due to the shorter length. I cut the strut to fit the length of the horizontal mount area behind the door and below the window.
Vertical Struts
After installing the horizontal struts with 8mm bolts into the rivet nuts, I measured out the proper spacing and length to install the vertical struts. As it turns out I could use the 12g (1 5/8″) struts for the horizontal support and it provided the correct spacing to have a 48″ vertical support. This allows the bed to be raised and lowered from the wheel wells to 48″ above the floor – which is a great height range.
For the vertical struts I used the 14g strut (13/16″) as they are plenty strong and have a lower profile.
After cutting the vertical struts, I located the top mounting locations where the vertical struts contacted the pillars. I drilled and installed the rivet nuts following the same steps as I did for the horizontal strut. (You may find you need to shim the upper mount point a little bit to make the strut vertical – I only had to use one washer.)
I noticed that many conversions deal with the curved outside of the van with custom spacers or adjustable bed panels. To me, it just seemed easier to use vertical struts which allow the same length cross members throughout the adjustment range.
Bed Platform
Based on what I had read in the forums, I thought the actual platform would be a major project. As we were eager to get out with the van, I quickly crafted a “temporary” platform out of 1/2″ plywood and 2×3’s. As it turns out, this proved to be pretty stout, relatively light, and ultimately turned into my permanent solution.
I created 3 panels for ease of removal and to allow for the front panel to be lowered and used as a seat. The panel frames were sized to rest on two moveable struts which were mounted horizontally along the van sides between the vertical frame struts. These moveable struts were mounted to the vertical struts using strut-specific “L” brackets and strut nuts.
I extended the plywood over the frame on the sides for additional width with cutouts in the front and rear panels to fit between the vertical struts. I also found I could extend the plywood on the rear and front platforms to make a slightly longer bed (76″ total).
I had more room to extend the width of the bed due to the rear side-windows. If you are converting a van with smaller or no windows in the rear (ugh), you won’t have much room to do this, but honestly, it’s only a few inches.
Under the sides of each platform, I added a short length (12″) of 1 1/2″x 1 1/2″ aluminum angle that fits over the outside of the side struts to hold the platforms in place. After a few weekends testing out the platforms, I covered them in utility carpet.
Cleaning things up
At some point during the summer, I was pretty satisfied with the setup, so it was time to dress things up a bit and make them permanent.
I checked out possibly powder-coating these, but it was way (way) too expensive -especially for an interior item, so I picked up some rattle-cans and went to work. (The paint has held up pretty well so far and it’s super easy to touch up.)
I took advantage of taking the frames out to do some other work including insulation (separate blog entry).
I also sprung for some nice hex-cap bolts for the framing. These gave a bit more clearance and look cooler. (I also painted the washers.)
Bed support rails are attached by 4 “L” brackets connected with strut-nuts and hex-head bolts.
The bed platforms are attached to the bed rails using bolts that run through the platform and rails then tightened by hand using these threaded knobs. The platforms can be removed by one person just a few minutes.
Summary
When writing this, we have used the van for dozens of weekends over the past year and the platform is pretty much perfect. I adjust it up for putting bikes underneath and lower it for trips with smaller toys. The adjustment is done by simply loosening the 4 bolts that mount the “L” brackets to the vertical struts and sliding them up or down. With the platform at 35″ for bikes there’s still enough room for us to sit up in bed. It only takes a couple of minutes to take out the panels for big loads or just to do work on the van.
The bed passed the Taiya test.
I read your post dated July 2020 on Sprinter Source regarding the Loctite fix for the drive line clunk. Which MB dealer in AK fixed the issue for you and was it covered under warranty being we don’t have an authorized MB van dealer in AK (per the site)? Has the clunk returned two years later?
Hi Joel,
I had my work done at Freightliner in Anchorage. Yes, it was covered under warranty as was the “update” to the transfer case controller which I had done at the same time. The latter was causing mis-shifting into and out of 4wd (and a host of other problems). Both were apparently known issues. The clunk has not re-appeared nor have the 4wd shifting issues.
Let me know if you have any other questions.
John
Where the vertical beams attach to the van pillar is it tilted? or do they come plum vertical? I am a bit confused because having them attached to the horizontal beam there would be a gap at the top and bottom. Does that make sense?
thanks
Tino
Hi Tino,
Sorry it took a while to get back to you on this. Yes, the sidewalls are tilted, but the vertical beams are plumb. At 48″ tall, I was able to fasten the top of the vertical beam directly to the van framing and the horizontal beam stands out just the right amount (1 5/8″) to allow the vertical beam to be plumb. I also anchored the base of the vertical beam using an “L” bracket bolted to the floor, though I could have used one of the unistrut base brackets rather than an “L” bracket.
John