Sprinter Westfalia #248 Refitting

I found a little rust today, that I think I have diagnosed accurately, but a second opinion or two would be appreciated, as well as guidance about what if anything additional to do beyond neutralizing and painting the area.

The rust is in the bed just forward of the rear drivers side wheel well. I first probed and tested the area with an awl, which removed the worst of the rust. As you can see in the video, the rust appears to have affected just the upper layer of the bed.

https://www.youtube.com/watch?v=UWtY4ZPvflg



I think the rust was caused from water from above, as this location was right below and adjacent to the kitchen sink, gravity water fill and fresh water holding tank, so a leak or drip over the last fifteen years at some point is highly probable.

I looked around under the chassis for anything suspicious, but everything looked free from rust. What did catch my eye where the multiple voids/holes in the undercoatings lining the wheel wells.

Questions:
1. Shouldn't the wheel wells be absent of any holes for water to enter into the frame ?
2. If so, what should I use to fill these holes ?



After exploring the area with an awl, I took my grinder and cleaned away everything that was rusted. The bed is multiple layers of steel, so I could pry up the top most layer to peer under it and didn't see anything of concern beyond the area that I removed, further suggesting that the water source was indeed from above and not coming up from below.



I literally poured and filled the area with Right Stuff rust neutralizer, then took a paint brush and worked it as far into the area between the layers of steel as I could.

Question:
3. Besides painting anything else I should be doing to this area ? Should I seal and cover it with Sikaflex and a metal plate like I did all the original Westfalia holes that went all the way through the bed ?

I finished my tear out and am back to neutral...61 square feet never looked so promising.



The most difficult part of the tear out was getting the two rails and one big steel plate installed for the rear bench seat removed from the floor. The two rails were a combination of aluminum extrusions adhered to 1/4 thick steel plate.



The rail near the sliding door was relatively easy to remove as the aluminum extrusion was a simple shape with a single bottom flange and there was far less steel as the rails location fell directly over a flooring rib for all of it's length except for a relatively small steel spacer at the rear. I could use a multi-tool to cut the adhesive and then a 6 foot digging bar to pry the aluminum up and roll it off the bed.



The steel spacer under the rail and the big square plate, I cut into smaller pieces with a grinding wheel, being very careful to gauge my depth of cut accurately so that I did not cut through the metal Sprinter deck. The adhesive used to bond the steel to the deck was anywhere from 1/8 to 1/4 thick, so that was my margin of error for not cutting into the deck.





The rail behind the drivers seat was a whole different story. There was far more steel under this rail and the rail's bottom flange was a box beam extrusion too stiff to bend and roll up like the rail adjacent to the sliding door. I ended up having to cut this rail and steel spacer into short sections that I could then pry up from the side.





Initially I almost gave up on being able to remove these rails. I had tried a couple of different cut off wheels with almost no success - they just couldn't cut the steel and barely the aluminum. I then stumbled across a welders forum and a thread about cut off wheels with a link to a study of 50 different cut off wheels. I purchased one of the top performers from that test and man these things are like night and day compared to the other more commonly available wheels that I tried.



Hindsight: 1. Modern adhesives are far stronger then I had ever imagined. Cutting the adhesive with a carbide tipped multi-tool was not easy going, but paled in comparison to the force required by my scrawny ass using a 6 foot lever arm to detach even short sections of rail from the deck. It was this experience that gave me the confidence in modern adhesives to use the methods that I did to repair the various holes in my body panels.

Hindsight: 2. Don't wear cloth work gloves when using a grinder ... my left one caught on fire.

Good tip about the gloves!

I have always thought that if a Westy got too rusty, you could find a low roof 140” van from the west you could theoretically move everything over. Seeing how these rails are attached pretty much dashes that thought...

Quick update, best described as ... Poop is in the details.

While I have been sketching for years about my build and knew that it was going to be a design/build/design process in the truest sense of the term, I've kinda stalled now that I'm into the shop work because I haven't sufficiently committed/worked out all the details yet. I was literally almost the last class in my high school and then architectural school who learned drafting the old way, parallel bars. It was the class coming into college when I was graduating that was getting all up to speed on that new fangled CAD stuff. So no fancy drawings/eye candy to share here.



I have gotten my cellar floor, cab bulk head foam cores and garage bulkhead "roof" fitted. Plus I quickly made up some laminated curved sidewall ribs for the garage bulkhead wall. The cellar floor is 1 1/2" XPS foam with 1/2" MDO plywood on top of that. I am not filling in the spaces between the flooring ribs as I want to encourage air flow between the XPS foam and metal van floor. Currently, everything is attached with 1/8" trim screws. Once I feel I have the substructures designed and built how I want them, I will remove everything and use those 1/8" holes as pilot holes for installing 1/4" Plusnuts and bolts.





The plate that secures the cab bulkhead to both the van floor and my cellar floor unfortunately fell into alignment directly over the sloped forward ends of the floor ribs. This meant I had to cut the plate to fit the ribs so that the plate could bear squarely on the flat valleys between the ribs. Filling those forward valleys in, lessened my ventilation idea, as now only the rear plate under the rear garage bulkhead spans along the tops of the floor ribs allowing air to circulate under the XPS foam.





I scribed a cardboard template of the curvature of the van walls, which I used to build a simple laminating jig. After glue up, I ran the ribs over the jointer and through the planer to clean and dimension them up. The side walls and ribs are not a fair curve, but a segmented one.





I made up the garage bulkhead "roof" from 1"x2" spruce and foam. The garage will not be conditioned space, hence the bulkhead wall and roof will be insulated as part of the living spaces thermal envelope. I will adhere 1/8 inch tempered plywood to the underside of the garage bulkhead roof. The upper side will be in the living space with the center two sections serving as a raised counter space/shelf below the new rear facing window. I am not sure yet what the upper side finished material will be.



I soaked a piece of 1/8 inch tempered ply in water for 24 hours and was happy to see that it wasn't any worse for wear when removed and left to air dry. I did the same process with the same positive result to a piece of MDO prior to committing it to my cellar floor.

Water tank fittings conundrum...

Spin weld vs. Bulkhead fittings vs Uni-seals...which to use ?

I want to purchase my two 23 gallon water tanks without any holes in them because I am not sure of the locations of each fitting yet, but I would like to get the water tanks on hand because they obviously influence other decisions.

Uni-seals are cool, but I have a difficult time having faith in them when used in a moving vibrating vehicle, plus everyone seems to stick PVC fittings through them, a plastic I'd like to avoid in my potable side.

Spin welds seem to be the standard, but purchasing the necessary installation attachments is pricey for a one-off build and there's something about them, I just can't my head comfortable with...

Bulkhead fittings are where I am currently leaning and like these Bulkhead fittings made of polypropylene or CPVC, which are available in spin-on cinch or bolt-on. I plan to have a 6 inch access port in the top of each of my tanks, which makes installing these very easy. I'm not sure if those are food grade EPDM gaskets, but it's easy enough to make your own gaskets out of Food grade EPDM.

Any opinions/experiences would be appreciated. It's easy to over think this stuff and get into decision paralysis, especially when entering the vortex of health and chemical exposure ... anybody want to talk religion i.e. van insulation ?

Uni-seal install video

https://www.youtube.com/watch?v=Vv14eNJmUeU

Spin welding is a great approach, and you can get the fittings closer to the edges that most bulkhead fittings.

With is bulkhead fitting its possible to fit a pickup/siphon to the inside, which allows using 98% of the tank depth without putting a fitting through the bottom surface.

Chemical exposure is of minimal concern. Low surface area, extremely low solubility in water, etc.

I got my rear bulkhead made up and fitted. It's made up of 1x spruce in various widths with glued and screwed lap joints. Next, the 1 inch thick foam infill panels will be adhered to the wood frame with polyurethane Gorilla Glue. Then I will sheath the bulkhead on the cabin side with 3mm Baltic Birch multi ply, plywood. The cabin side sheathing will get glued and clamped, with no visible fasteners, to both the wood frame and foam while in the shop laying flat on the bench. The garage side will get the thicker 6mm Baltic Birch screwed to just the wood frame after the bulkhead is bolted into the van.

One of my complaints with the original Westfalia design, was that not only were things very difficult to remove, but much of the componentry was very difficult to access. The process of tearing out everything in the Westfalia only increased this complaint. One of my design intentions is to make future alterations and maintenance/repair easier by hopefully designing and installing things so they can be removed and/or accessed without too much gymnastics-will see how this goes as it's proving to be difficult.

There will be three 1/4 bolts through each of the bulkheads laminated curved side ribs into Plusnuts installed into the three horizontal steel ribs of the van. The bulkhead will also be secured to the cellar floor plate and to the forward edge of the garage roof, both of which will be bolted to the van. Finally, there will be a MTB storage deck in the garage bracing the bulkhead roughly in the middle of it's height.

So far the bulkhead panel is very light. I don't have a scale, but I'm guessing it weighs about 25% of what a typical cabinet grade piece of 3/4 plywood weighs, and is just as stiff as the plywood with the foam panels just press fit into place.





Having very little experience with polyurethane glue, I experimented a bit with various wood to foam and foam to foam glue ups. It's amazing how strong the bonds are. I also played with the Astro 1450 Plusnut Tool that I just purchased. The 1450 will reportedly also install Rivnuts. I was happy to see that the Plusnuts installed into both 6mm and 1/2 cabinet grade plywood without any deformation of the material.

I wasn't happy with my first idea/test for gluing the foam into the wood bulkhead frame, which was to bevel half the edge of the foam and then apply the glue into the bevel after the foam was press fit into the frame. There was poor distribution and not uniform adhesion. If you simply smear one of the surfaces, then press fit the foam into place, most of the glue comes off on the face of the frame or foam, resulting in really poor adhesion.

My second idea/test was to cut a shallow kerf in the center of the edges of the foam. The kerf provides a place for the just applied polyurethane glue to catch a ride into the frame without getting smeared off. Once the foam is press fit into the frame the polyurethane glue starts to expand distributing itself equally out both sides of the frame/foam joint. It worked really well and cleaning off the excess after it cured was really easy. Now the rear bulkhead is ready for it's skins.





With the rear bulkhead mostly finished, it was time to mock up my idea for stowing the bikes. No attachments points yet, just setting them in there to make sure I provided enough space for them to nest together. Was Van/MTB Life even possible before dropper posts? The bikes being relatively light, go up high on a shelf. My kayak and a large drawer will be in the center section below the bikes. There will be additional storage and service panels off to each side. The foam in the garage roof isn't glued in yet, so I removed the two center pieces to make checking out the bike fit easier with the rear doors closed.

I've been accomplishing a bunch of disparate stuff, which is good, but it "feels" like I am treading water because nothing is actually getting installed in the van. One off, solo van conversions are a huge commitment...my hats off in respect to everyone that's completed one.

I built two more laminated curved ribs for the forward bulkhead. After laminating them up, I put them over the jointer then through the planer prior to gluing them to the foam cores along with the center ribs. The center ribs are mahogany, which will be exposed and serve several functions...more on them later.





I glued on the first skin, a 3mm, three ply piece of Baltic Birch ply, to the underside of the garage roof. Prior to adhering the skin, I reinforced the center strut, with glued and screwed poplar corner blocks, to help carry/transfer the loads of a hammock that I plan to be able to string down the center galley for naps and to hopefully use as a guest bedroom. I also added two steel brackets to the back of the garage roof to fasten the roof to the rear wall of the van.




While it's premature, I purchased my new Espar D2, so I can have the components on hand as I get ready to start constructed the cellar and primary floor structure, which is where these components will reside. The D2 is a lot smaller than the D4 that was installed in the original Westfalia. My redesign, as opposed to the original, is going to be very well insulated with fewer better quality windows, plus my enclosed primary living space/thermal envelope will be 35% smaller than the original design - hence the smaller heater. The D4 is for sale.




I had some design break throughs recently, the primary of which was to move my stairs from the typical front to the rear of the sliding door opening. Moving the stairs to the rear, will cause less space to be consumed for primary circulation, allowing for a dedicated sitting/table area forward of the stairs right behind the forward bulkhead. I sketched out a simple table design, that when deployed will hang from the two center mahogany ribs of the forward bulkhead. I'm pretty psyched about the sitting/eating/table situation-hopefully I will be able to successfully execute what I am envisioning.



I took advantage of one of the recent warm days to pull off a "foundation" repair. There was some rust along the front seam on the underside of the hood. I pried the seam open, wired wheeled the loose rust away, neutralized the area and then sprayed on some primer. It looks like this seam was originally crimped closed with some liquid sealant in it, which I will do next, followed by a top coat.

Totally enjoyed my visit; now I wish I had seen your shop. It looks like a great place to build this sort of thing!

When you're done, you will have the most innovative camper on the road today, and with your skills, I imagine the execution will be first-rate.

Moving along slow and steady and more importantly I haven't had a major F-up yet-or at least one I am aware of...

I got the 6mm Baltic Birch skins adhered to both sides of the forward bulkheads, then got the bulkheads fitted into the van. They are heavier than I'd prefer, but also a lot stiffer than I originally imagined, rock solid really, which is good considering that I've come up with the idea of hanging my table off of them. The wooden box in the first photo represents what will be the finished floor height. I also got the two lower and one upper bulkhead plates plusnutted to the van, which went well without any surprises like puncturing the fuel tank. There's a lot more work to do on the forward bulkheads, but I am trying to get things along to where I can start on the cellar floor structure.




I've been sketching out some details to come like the galley wet floor structure and grey water tank/drain basin. I also came up with a second draft of my table structure, which I like much better than the first draft. I test fit the guest bedroom/post ride recovery apparatus. The next task is to skin the cabin side of the rear bulkhead while continuing to cogitate on just how the hell I am going to carry out modifying the upper fiberglass top to install my new three windows.

Very nice.

You might see if you have a local supplier for FRP composite panels. Typically they have two FRP skins (1-2mm thick) with polycarbonate honeycomb core. Excellent compression and tensile strength, very lightweight, and can be worked with normal wood cutting tools. You would bond in with some aluminum extrusions or similar.

I got the cabin side of the rear bulkhead skinned with 3mm Baltic Birch...total weight so far is 27lbs. I installed the Plusnuts for both the rear bulkhead and the garage roof and they both bolted in quite nicely. The rear bulkhead bolts in through recesses in the foam that will remain accessible from the garage side.





The flexible flashing hanging on the rear bulkhead is the beginning of my wet galley floor which will serve as my bathing area-hope this idea works. I did some more adhesive testing and continue to be impressed with Sikaflex-it bonded tenaciously to the flexible flashing which is listed as a polymer(whatever that means exactly). The polyurethane Gorilla Glue slid off of the polymer like a sled on ice. West System Epoxy continues to adhere to anything I put it on. I also glued up sample sections of my floor rib ideas, and took them to the digital scale at the grocery store to get some comparison weights between the three options.



I routed out a relief area in the panel to hold the 40ml thick flexible flashing, then adhered my first skin over it using polyurethane glue for the majority of it, but the Sikflex where the 3mm BB overlapped the flexible flashing, which has an adhesive backing of it's own that stuck really well to the foam/wood. Prior to adhering the 3mm BB down I sealed the bottom edge and back side where it overlapped the flexible flashing with West System Epoxy.




Prior to adhering the skins, I use a router/sled setup to remove the expanded polyurethane glue left over from adhering the foam into the wood frame, remove any manufacturers ink with lacquer thinner, lightly sand the panel, blow the panel off, then use a perforated roller to increase the bonding area. I've been using some concrete pavers as clamps during the glue ups.






Like the front bulkhead, the rear bulkhead still has work to do on it, but I want to get to the cellar floor structure, because there's a lot going into/riding on that with a lot of room for F-ups and/or missed opportunities. I ordered my two 20 gallon water tanks, and have the D2 on hand to help in the layout. Here's the most current sketch of my idea. The big areas with diagonal crosses through them are under floor storage areas, the biggest of which is a large pull out drawer/outside table. Looking forward to seeing how well this plays out.

Man, you're gonna have crazy amounts of storage for a 140" wheelbase van. Actually, crazy amounts of storage for any van!

Nice job keeping the tankage centered, and balanced. Is the gray water going overboard via a pump, or a gravity drain?

The hard part with all that storage is not filling it with heavy stuff!

Riptide said:

Man, you're gonna have crazy amounts of storage for a 140" wheelbase van. Actually, crazy amounts of storage for any van!

Nice job keeping the tankage centered, and balanced. Is the gray water going overboard via a pump, or a gravity drain?

Click to expand...

Thanks Pat. The grey tank will empty via gravity.

Midwestdrifter said:

The hard part with all that storage is not filling it with heavy stuff!

Click to expand...

All those yards of coco husks and peat moss that I'll be storing down there to constantly feed my composting toilet aren't very heavy.

Compacted and dehydrated coco husk is surprisingly dense. I bet you will have plenty of space to temp you.

I built the structural ribs for my primary floor and tacked them in on top of the cellar floor to help me visualize the spaces better in order to make what seems like an infinite number of decisions necessary to pull this all together some day.

I feel I have a very good handle on the living space, and pretty good grasp on both the plumbing and heating systems. It's the electrical system, which is the weakest link in my skill set, that I now have to move farther along. The exact components I choose and where I install them will determine what spaces remain usable storage. Some of the under floor spaces will end up being more accessible and packable than others, which makes all of this like a rubics cube. Where to stick what so I can get to that and service this or that without having to remove this Fing thing while not buring that little space behind this forever..all the while trying to distribute weight appropriately...is giving me a real challenge. I've been going in circles on this a bit and should take a break and do some MTBing, which I have been foregoing for a while in order to work on the van. This build is going to take a long time... it's fun and exciting, but I need to pace myself.    

You are making great progress!

On thing to consider with those twin water tanks is how to join and vent them so that you can get a good fill rate. Best to do some prototyping before they're installed.

Ted

Thanks grozier.

My current plan is to connect the tanks down low with a piece of 2 inch diameter tubing, and have another 2 inch diameter piece from a gravity fill port probably on the side of the van to the upper part of one of the tanks. I'd like to install the fill port inside the rear or sliding door, but I fill up a lot of the time with a collapsible bucket from natural sources-mountain streams mostly-which can get a bit messy, so keeping it on the side of the van ensures what I spill falls harmlessly to the ground outside of the van.

For venting I can't connect the top of the two tanks, as you can see in my sectional sketch below, so I am planning on running some 3/4 inch tubing from the top of each tank up to the underside of the counters 36 inches above the top of the tanks.

I could easily run the vent tubing over into the rear storage area and then up to get them up about 48 inches above the tanks, but can't see why that would be necessary....?

My hope is that the larger 2 inch fill/crossover tubing and 3/4 vent tubing will allow me to dump the water into the tanks faster than I could in the original Westy tank, which had a 1 inch fill and 1/2 vent.

What do you think, will that work, what don't I know ?