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Eric's Neverending Story

170K views 94 replies 37 participants last post by  OutOfTheNorth 
#1 ·
This spring my wife and I decided to sell our travel trailer and try a camper van instead. This would allow me to handle the "let's stop here" request without anxiety over an exit strategy with the trailer. I hate disconnecting to get out of a jam.

We couldn't find a factory model that suited us so I said "let's build one, piece of cake". Yeah, right! This job took much longer than I promised but we are now just about ready for the maiden voyage after missing the summer camping season.

It turned out our requirements made it difficult to fit everything into the 136" wheel base Promaster we wanted. At my age a bathroom was a necessity (all you that suffer BPH know what I mean). We also needed the stuff we enjoyed in the trailer - a stove, fridge, heater, fresh and gray water system, electrical system, dining area, and a decent bed. Consequently planning took a long time. I used much info from the Promaster forum and the great builditsolar.com site.

With a rough plan in hand we bought a 2015 diesel high roof 136" WB Promaster with a lot of great options. The most appreciated were the factory trailer hitch, power mirrors, speed control, back-up camera, and park assist. I also really like the automated manual transmission in the diesel version.



The only way to fit all this stuff in was run the bed crosswise, utilizing the 74" width of the body. I am 72" tall so this was satisfactory when I mocked it up. The bed would turn into a dinette for daytime use that is located at the very front of the cargo area. This meant that one could not walk inside from the cab to the camper section, which was a reasonable trade off. This scheme makes use of some space in the cab by moving the seats all the way forward for camper mode and then deploying a hinged panel that makes the bed wider. Here is the initial plan:



The drawing shows the folding panel behind the seats and a leaf the hinges up from the right side dinette seat. A panel stored under the seat is then placed to bridge the gap from the leaf to the left side dinette seat. The table is dropped to seat level and the cushions rearranged to make the bed. There is just enough room to squeeze out the sliding door when the bed is made.

The other cabinets and fixtures are similar to those seen in other conversions. The stove and water heater run on propane, the fridge is 12 VDC electric, and the heater is an Espar diesel fuel model. I didn't want to deal with a black water tank so I selected a Thetford C-200 toilet with a removable waste water cassette. The access to the cassette is through a door at the back of the toilet, which allows me to remove the tank through the van's back door. This toilet is not imported into the US but I was able to get one from the UK via eBay.

I also included an inverter in this design, which I didn't have in the trailer. Now we will be able to run the microwave and TV without being hooked up. The inverter/charger is a pure sine 2 KW unit running off two 6V AGM batteries.

Here is list of some of the major items purchased for the conversion:


  • Thetford C-200 Toilet
  • Nova Kool R4500DC Fridge
  • Manchester 6814 ASME propane tank
  • Flexco FP-1220 Retractable step
  • Luverne grip steps for cab doors
  • Barker 10109 20 gallon fresh water tank
  • Ameri-Kart HT189B Holding Tank
  • Right and Left windows by Motion Windows
  • Garelick Eez-In Adjustable Table Pedestal
  • Moen Kg2045522 Sink
  • Ramblewood GC2-43P cooktop
  • Aquajet 55QUAJET-AES fresh water pump
  • Panasonic NN-SD37S microwave
  • Espar Airtronic D2 diesel heater
  • Espar Digi-Max D1000 controller
  • Atwood GC6AA-10E propane water heater
  • Cole Hersee 48530 smart battery isolator
  • Fan-Tastic Vent Fan
  • US Battery AGM 2000 6V Batteries
  • Kisae Abso Sinewave Inverter-Charger, 2Kw (IC1220100)
  • Fiamma F65S Awning

I will follow up with more posts later showing the construction details.
 
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#4 ·
I am looking for simplicity so this step is strictly manual. I would never need to deploy the step automatically or from inside the van because one can't get from the cab to the camper section without going outside. This was one of the few steps I found that has a small enough drop from the mounting flange to fit the Promaster.

 
#3 ·
Welcome to a Convertion Process !!!
My wish and experience = Keep van drivable , at least for weekends=
Do not anchor it in garage with excuse (Thi'z iz not DONE yet )
 
#7 ·
Interior pictures or progress pictures? Where is your 20 gal tank and grey tank? If under the van I would like info on source and specific model and mounting info. This is one of the most unique layouts we have seen. Thanks for posting.
We did a 136 too and love that you can go and park anywhere, however a 159 would be much easier and most folks thinking of converting probably should consider one.
 
#8 ·
Eric's Story - Insulation and Interior Panels

The first task was to install sound damping and insulation. I wanted the conversion to be as reversible as possible to make changes easy. Consequently I decided not to use spray foam, glue, and wiring inside body frame members where possible. The floor would have 1/2" rigid foam insulation topped with 1/2" poplar plywood, later to be covered with vinyl flooring. The walls would have Dynamat damping, an insulation spacer, Thinsulate, and Reflectix. The spacer is to provide a ventilation path to prevent condensation on the van skin.

Here is the Dynamat installed. The 18 x 32 Xtreme Bulk Pack has just enough for the whole van.




The floor was leveled with rigid foam strips ripped from the 1/2" panels I got at Home Depot (what a mess that was).




Three sheets were required:




Then the walls were insulated after some wood framing was installed:










The roof insulation will come later after the fan is installed:




The wall insulation stack was covered with painted 3mm (1/8") poplar plywood:




To be continued...
 
#10 ·
Eric's Story - Ahhh, I just cut a hole in my 36K van!

After some anxiety I cut the hole in the roof for the Fan-Tastic vent. I did this hole by hand with a hacksaw blade from the inside using the frame as a guide. Some of the framing in the van was redwood left over from the deck on my home - light and rot resistant.








Next was the water heater cutout:




The cardboard was to prevent hot metal chips from damaging the paint:




I mounted the water heater from the inside because I didn't like the look of a boxy water heater protruding from the curved side of the van. This was accomplished by bending the water heater flange inward instead of outward. Other not-so-easy modifications were necessary to get the heater mounted. A drain was also necessary to allow water trapped in the water heater frame to escape.




Curved fairing strips were used to match the curvature of the body:




Now for the windows:






I got the windows from Motion Windows that were specific to the Promaster. They matched the body curvature well and look great. The left window had a problem with the slider not closing properly due to the frame assembled wrong. They gave me the option of shipping the window back (no way) or driving to Vancouver (not thrilled) to get it fixed. I was able to fix it myself by removing the slider and using a die grinder to remove the interference.






To be continued...
 
#12 ·
Eric's Story - Thanks Ram for all of the underbody clutter

It was time to install the step and find a place for the propane tank, gray water tank, and fresh water tank. The step was mounted toward the rear of the slider opening, just aft of the right dinette seat:






Redwood spacer blocks were used to get the step level:




Bolts through the sill supported the front of the step:




I was able to find a 20 gallon holding tank from Ameri-Kart that just fit under the van next to that annoying parking brake cable. Really Ram, why run the cable right down the middle of the van? I had to trim and notch the edge of the tank to get it to fit. The tank is supported by a welded angle iron frame:




I added a rock shield at the front of the tank frame:






A decision was made to ditch the spare tire to make room for the propane tank and fresh water tank. In 50 years of driving I have never had a flat that could not have been fixed with green goop and an electric air pump. If I really need a spare I will use a trailer hitch mount. The ASME propane tank from Amazon was mounted at the rear just ahead of the trailer hitch. Eight bolts with backing plates through the floor fastened a welded support frame to the van.




The 20 gallon fresh water tank was supported by a welded frame and installed just in front of the propane tank. As with the gray water tank a rock shield (made from one of the window cuttouts) was included.








The outlet of the gray water tank was a little too low for a gravity drain so I installed a chopper pump. The pump also allows use of a garden hose for the drain (no huge ugly drain hose to store). Since the pump was to be mounted under the body I enclosed the motor in a piece of ABS pipe for protection. The threaded plug at the end is for access to the motor shaft, which can be turned to clear a jammed pump.






To be continued...
 
#95 ·
The outlet of the gray water tank was a little too low for a gravity drain so I installed a chopper pump. The pump also allows use of a garden hose for the drain (no huge ugly drain hose to store). Since the pump was to be mounted under the body I enclosed the motor in a piece of ABS pipe for protection. The threaded plug at the end is for access to the motor shaft, which can be turned to
The part about the grey water tank outlet being too low for a gravity drain confuses me. Don't you want a gravity drain to be as low as possible?
 
#13 ·
Eric's Story - Ceiling

The ceiling was insulated with Thinsulate and Reflectix. There was not enough room for the ventilation spacer - this will probably be ok since the Thinsulate is hydrophobic.






The ceiling panels are painted 3mm plywood screwed to the framing. The thin plywood was a little to floppy so I had to glue stiffeners on the back side. I should have used 6mm ply instead. The panels were cut to allow removal when the cabinets are in place. Holes and wiring were installed for the LED lights.






To be continued...
 
#14 · (Edited)
Eric's Story - Will 12 sheets of plywood ever fit?

The cabinets were framed with clear poplar and skinned with Lite Ply, which is a clear poplar plywood imported from Italy. It is very light, void free, and very expensive. The surface is quite soft and does not stain well so I decided to paint the cabinets. The poplar framing material is great to work with - it's light, stable, easy to paint, and holds screws very well.

The first order of business was to build the dinette since it was critical to the whole design concept. The dinette cabinet is anchored to the van body with a 3/4" plywood bulkhead bolted to the floor step just behind the seats.








The right dinette seat has a retractable back rest to support the cushion when the door is open.




The back rest retracts to provide a full 74" of length for the bed:




Sleeping mode:




Eating mode:




The next order of business was to frame the galley, fridge, and wardrobe cabinets. The tall cabinets are built in upper and lower sections to allow installation and removal from the van. This is necessary because the van door height is less than the roof height.






The cabinets tie into the body structure using bolts, rivnuts, and sheet metal screws.




12mm (1/2") plywood was used to skin the frames:






The galley is framed for two drawers on the upper left and doors elsewhere:




The all-important bathroom was built next. It is constructed of 12mm plywood on all sides except for the upper back, which is 3mm plywood. As with the fridge/wardrobe cabinet the bath is made in an upper and lower section to allow installation. The bathroom is also a shower so it will be waterproofed with glass epoxy on the inside.








Next was the storage cabinet next to the sliding door. This was built full-height because it could be installed by removing the top forward panel and tipping it into place through the door.




Finally the overhead cabinets were constructed. Since there could be a lot of weight in these cabinets they were fastened to the framing in the roof, the body at the upper corner of the dividers, and the wall at the back of the cabinet floor.




To be continued...
 
#18 ·
Eric's Story - Finishing the Cabinets

After checking the fit in the van all of the cabinets were removed and set up in my garage for finishing. The Lite Ply is quite soft and porous so I intended to paint the cabinets with primer and then Benjamin Moore Advance. When dry this stuff is very tough but it does take a long time to cure. If I was doing this again I would probably use a paint that cures a little faster.

The interior of the bathroom was finished with glass-epoxy to make it waterproof. All of the inside corners were filleted with micro-balloons and covered with one layer of glass tape. The floor was sloped and profiled for the drain, and then got two layers of glass cloth. Then the entire inside surface was coated with epoxy resin, and later, with white paint.

Glass-epoxy on the bathroom:








I couldn't find a sink small enough so I used an aluminum serving bowl. The wall mount faucet saved space as well but I had add the shower diverter valve.




Here is the access to the toilet cassette:




There were a lot of surfaces to prime:






Cabinets with the finish coat - a green tinted gray color:






I set up every ladder I had to act as a drying rack for panels and doors:




The painted cabinets back in the van:






To be continued...
 
#20 ·
Eric's Story - Plumbing and Electrical

The propane and fresh water plumbing was done using 3/8" copper tubing. I used flare connections for propane and compression fittings for the water system. The small diameter tubing reduces the amount of water wasted waiting for hot water to arrive at the tap.






I wanted the fresh water fill port to be inside the van, both to eliminate a hole in the body and provide security against tampering. I came up with a hinged fill port that extends beyond the back door opening. Any spillage will go on the ground instead of inside the van. I did not include a city water inlet as I never used it when camping in the trailer.






I didn't take any photos of the drain system, but it is very straightforward. All drains feed into traps located under the floor, then into the top of the gray water tank. There was limited space so I used flexible PVC pipe in many places. The tank is vented through a branch off the bathroom sink drain just ahead of the trap. The flexible vent tubing connects to a branch from the sealed toilet chamber and then to the roof. The vent pipe is shown at the right in the following photo:




I came up with a simple gray water tank level gauge that uses a method common in industrial applications. It uses an aquarium air pump to force air into a port at the drain of the gray water tank. This is the lowest level of the tank and the pressure necessary to expel air is proportional to the level in the tank. I purchased a low pressure gauge on ebay, calibrated in inches of water, to measure the pressure. The reading indicates the level of waste water in the tank in inches.






Electrical loads are powered by 12 VDC from two 6V AGM batteries. I tried to get US made Trojan batteries but they were on back-order so I ordered some from US Battery, which claimed to be made in the USA. That's true for their flooded batteries but the AGM version I received were made in China.

The batteries feed various loads, except for the inverter, through a DC / AC distribution panel. The inverter has a direct connection to the batteries through a 300 amp fuse. I used Bussmann marine fuses for all of the high amperage applications. They are really small and mount directly on the battery posts using a compact holder.

Here are the batteries mounted with a custom welded holder. The little red cap on top is a dual fuse holder for the 300 amp inverter circuit and 200 amp van battery circuit. The battery holder is mounted on blocks to allow room for plumbing underneath. This area was the only available for water and propane lines.




The AC system consists of the inverter/charger, external shore power connector, and the DC / AC distribution panel. The 2 KW inverter has a pure sine output and and a temperature compensated charger for the batteries.




The PD5000 DC / AC distribution panel was the same one used in the builditsolar van conversion. The DC branch circuit fuses are on the right and the AC circuit breakers on the left. I cut the AC bus-bar between the 3rd and 4th breakers to get two AC distribution circuits. The top 30 amp breaker is the shore power input, the second breaker is the inverter/charger branch, and the 3rd dual breaker is for the water heater and an outlet on the panel.

The output from the inverter feeds the 4th breaker (20 amp) to energize the dual breaker below, which feeds the microwave and van AC outlets.




The space behind the distribution panel is used for wiring and left open to provide ventilation for the inverter and refrigerator.




To be continued...
 
#24 ·
Never built a boat but have rebuilt an airplane. I have an engineering background so I enjoy finding elegant solutions to problems. Not interested in a boat because it truly is a hole in the water you throw money into. I see boat owners at the nearby boat yard ripping rotten planks off the hull, scraping bottom paint, varnishing bright work among other things. Not for me.
 
#22 ·
Eric's Story - Finishing Up

The van is starting to look like a real camper now. I have lights, AC power, water, and heat. I forgot to mention the Espar heater in my previous posts. It is located just to the right of the batteries as shown below. The heater fuel pump is located up front under the left dinette seat.






The counter and table tops are laminate on 18mm Lite Ply, with gray tee molding on the edges.






Here are some photos of the interior with the doors and drawers installed. I added a stainless backsplash because I was concerned that the cooktop was a little hotter than a normal RV cooktop. The photos also show the left window frame and valance below the overhead cabinets. The valance covers the mounting screws and lighting wiring.
























I mounted the TV above the right dinette seat at the forward end of the sliding door. It is high enough that I don't hit my head while seated and far enough forward that it does not restrict the doorway.




I ordered a Fiamma awning from Eurocampers and installed it over the doorway.




Controls for the inverter, heater, and lights are on the panel just to the left of the doorway.




I was thinking about a ladder on the back door but found this telescoping ladder that is much more versatile, less expensive too. It collapses and stores on the back door.






The window treatment includes blinds for the galley window (installed but no photo), Velcro attached reflectix on the door window, magnetic attached reflectix on the back windows, and a suction cup attached cover for the cab windows. The cab window cover was purchased from Eurocampers. Here are some photos of the back window cover, which conveniently stores on the door.










This brings the posts up to date with the conversion. The cushions are on order with a local upholstery shop. I just received a late model Toyota Sienna center console purchased on ebay, which fits between the front seats perfectly. I will probably put it on a spacer to raise it to be level with the seat. The console has two cup holders so I am going to pull out the Promaster cup holder and replace it with a holder for maps and books.

So that about does it. I thought I would get to this point months ago. This project gives me a new appreciation of all of the conversions detailed in this forum as well as factory made Promaster campers.
 
#23 ·
SPECTACULAR WORK!

Wow, so much to catch up on. Congrats, it really looks great!

Specifics on the ladder would be greatly appreciated... Christmas is coming soon, and a few people I know are looking for the perfect gift for me!

Without the center console, it appears that you actually could step into the back if the table was not in place. Might be useful on rainy or snowy days....

Ed
 
#32 ·
z120pi,

A truly inspirational build!!

Thank you for sharing it with us. Your pictures are super helpful.

Could you please expand a bit on your thought process on using the rain screen and why you chose the the Benjamin Obdyke Rain Slicker.

I have been considering using rain screen as well but, have not taken action on it yet. Are you thinking you will eliminate the possibility of condensation using the rain screen? As I understand it it is usually used to provide air circulation (to promote evaporation) and a path to drain the condensing water. I do not have any direct experience using rain screen so any thoughts you can share would be great.

How did you secure the composite layup on your walls?

I am on the same path as you, maintain access and install nothing permanently. I am considering using velcro to fasten insulation to the van skin. I have the same insulation materials with the addition of closed cell foam.

Did you do any tests with the radiant barrier?

I am starting to question the effectiveness of the radiant barrier. If an air gap on both sides cannot be designed into the the system it seems to range in effectiveness from marginal to completely counter productive. I exclusively insulated my 12' X 30' portable garage with EZ-Cool radiant barrier. I have a 2" air gap except where the barrier is attached to the metal frame ribs. It worked reasonably well in the summer but now that I am into fall/winter temps I have had quite a bit of condensation occurring.

Thank you again for sharing your build.

Cheers,

Dave
 
#34 ·
My thinking was that the rain screen would provide an air path to get evaporated moisture away from the walls of the van. Not sure if this is valid but there was room in the wall cavity to try. I wanted to conserve headroom so I did not put the screen in the ceiling cavity.

The screen was stiff enough that I just stuck it in. The Thinsulate layer expanded and held the screen in place. I put the Reflectix layer on to provide a vapor barrier as well as some insulation, but I have done no testing on its effectiveness.
 
#33 ·
z120pi,

A mundane question, how did you post your pictures with out using up your data limit?

I have been using the attachment process built into the site and reached my limit on the free data. Your pictures are embedded in the post and can be seen even by non members. How did you do this?

Thank you,

Dave
 
#35 ·
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