Ram Promaster Forum banner

1 - 20 of 23 Posts

·
Registered
Joined
·
3 Posts
Discussion Starter #1
We are at the start of our design and are looking for information about what people have done to minimize the effect of a rear-end or frontal collision, i.e, preventing the contents from flying forward into the driver and passenger. We have a few other questions, too!

1. Our biggest question is, what do (did) you do to ensure that your cupboards and their contents didn't come off the walls or floor if you got into a collision? How did you secure the drawers, where did you store sharp objects and tools for travel, where is your pet while you're driving? I've been researching the forces generated by as little as a 30-mph rear-end collision and am seriously concerned.

2. Our design includes a partition with a 20", windowed door opening toward the driver's seat. We want to enter and exit the van primarily via the passenger side door from the cab area (if you are curious, our reasons are below) and then into the living area through the partition door. Apart from having to duck and slide, is this realistic? What problems can we expect to encounter if we do this?

3. We're planning to convert a 159" high-roof. Will we be able to hang our two batteries, a 15-gallon water tant, and both a 15 gallon grey-water and 10-gallon black-water tank under the van floor? What are the pros and cons of doing this?

4. We're boaters, familiar with zip-up screening surrounding the cockpit of a boat. We'd like to use the same approach to screen the side sliding door area and the rear door area, with the zip coming down one side. Apart from the need to unzip the screen to get out, what problems or constraints can you see this introducing? We expect we'll have to use a marine place to do the design and install.

5. We will have one MaxxFan in the rear over the bed and one forward, near the partition. Because of this and because we plan to keep the the screened doors open in good weather, we're considering having only one of our windows open, the one over the kitchen area. The others would be fixed. Can you see any problems with this?

I've learned so much in the last few months lurking on this forum! Now that we're in the planning stages, I look forward to getting your views on our ideas. Thanks in advance for any responses!

WHY WE WANT TO USE THE DRIVING AREA DOORS and HAVE ZIP-UP SCREENS
Our two indoor-only cats will be travelling with us. They almost always hope to go walkabout and keeping them inside when we open the huge sliding door will be difficult. It will be impossible if we have magnet-based screen curtains. Hence, the two-stage entry and exit process (partition door and then passenger side cab door) and the heavy-duty zip-in screens.
 

·
Registered
Joined
·
908 Posts
You’ve proposed an airlock for cats. How novel.

I cant really speak to most of your questions, but I can say a few things about hvac in promasters. We sleep in ours year round, and it’s much more difficult to stay cool in the summer than warm in winter. You’ll find the $150 chinese diesel heater (ebay) is more than enough.

What will get you farther than real a/c is insulation. The floor and walls dont need it, but simple foil backed styrofoam board (home depot, 1/2” is plenty) on the ceiling and ANY kind of fan is enough unless it’s over 100 out. Exterior ducting is probably not needed.

Suspending things below the van is probably not a problem either. We regularly put 4300lbs on top of the same sheetmetal with no issues. I’d be concerned about ground clearance more than static weight issues.
 

·
Registered
2014 136” HR
Joined
·
4,676 Posts
I can’t address the partition door, but I regularly use the passenger door to access the rear and it is not difficult. Instead of facing backward toward the seat, I normally just sit in the seat during the transition. Unless I’m carrying something bulky or potentially messy, I usually prefer the passenger door.

Consider making your kitchen window a Motion slider that can be used as a pass-through—easy way to transfer stuff in-out without door or zipper.
 

·
Registered
Joined
·
892 Posts
Lots here. 1 - Cabinets get secured to the walls with riv nuts and bolted through the floor. Backing plates under the van. All structural boils are grade 5. All drawers/cabinets have positive latches - just like a boat. Anything left on the counters ends up on the floor at the first stop sign, so everything gets put away.

2 Regularly passing from the cab to the back is for trim or flexible people. We had to take the arms rests off to make it practical for us.

Mounting things under the van is complicated by the exhaust lines and the parking brake cable. I had my exhaust pipe shifted ($300 in california). I've seen reports of having the brake cable moved. Some of what you propose can be done without moving anything, but the more you put, the harder it gets. Very few DIYs hang the batteries outside. For me it wasn't worth the effort.
 

·
Super Moderator
Joined
·
8,678 Posts
This is going to be a very interesting build thread, indeed!
 

·
Registered
Joined
·
324 Posts
We are at the start of our design and are looking for information about what people have done to minimize the effect of a rear-end or frontal collision, i.e, preventing the contents from flying forward into the driver and passenger. We have a few other questions, too!

1. Our biggest question is, what do (did) you do to ensure that your cupboards and their contents didn't come off the walls or floor if you got into a collision? How did you secure the drawers, where did you store sharp objects and tools for travel, where is your pet while you're driving? I've been researching the forces generated by as little as a 30-mph rear-end collision and am seriously concerned.
All of the lower cabinets and accessories in my build are modular and easily removable, so I had to do things a bit differently than most. I added lengths of L tracking along the base of the walls and bolted directly through the van floor. When the cabinets are removed I use that L track as a tie down point for whatever loads I'm carrying, but the cabinets themselves are built to slide right up to it, and secured using tie downs. I recycled much of the L track and tie downs from a retired handicap bus, so it's definitely strong enough to hold the cabinets back in an accident.

As for the upper and lower cabinets one good thing to do is build them with a 1-1/2-2" lip in the front. That way most things won't be pushing against the actual cabinet door. I don't have any other devices holding my upper cabinets closed, but the air struts that keep them open do add some resistance. The lower drawers all have multiple spring loaded latches and an added eye hook latch that I only used if traveling off road. Of course none of this would be of much help in an accident, but since all of the drawers open towards the center aisle, they wouldn't be very likely to be projected towards cab in most accidents.
 

·
Premium Member
Joined
·
1,663 Posts
Hi,
I do think that securing cabinets to the van structure is very important and probably does not get enough attention.
A pretty good way to get in the ball park of how high the loads can be is to figure a 30g frontal collision -- this is what was commonly used for analysis before finite element analysis allowed more accurate numbers. So, a cabinet and contents that weigh 250 lbs at 30g's generates a load of 7500 lbs trying to pull the cabinet off its mountings.

I did two things to try to make the cabinets and contents crashworthy. 1) Attach the floor mounted cabinets through the floor metal using SEVERAL 1/2 inch bolts, and place large thick "washers" below the floor to keep the bolts from tearing through the floor metal. If the cabinets are tall enough to get up to the main longeron on the van frame, then also bolt to it -- the taller the cabinet, the more the need to bolt to both the floor and the van side longerons. 2) make the cabinet frames strong by using 5/8s or 3/4 inch good quality plywood for the load carrying part of the frames, and glue and screw the frames together -- glue is important for strength.

I don't have wall mounted cabinets, but If I did, I'd use rivnets to the van frames and longerons and strong glued and screwed cabinet construction.

Some pictures of our cabinet construction:
and

We have an anchor point for the dog so that he can wear a harness and sit/lay on the bed while attached to the anchor point. I have to admit that we are not very good at using it consistently, but its a good idea for both the dogs and your safety.

We have a maxfan and still appreciate being able to open all four of the windows on the sides of the van.

Gary
 

·
Registered
Joined
·
259 Posts
I won’t repost everything here, but feel free to peruse this post for an accident report and this not current website if you want to look at how we built our van.

The gist is that we used a lot of plus nuts (like rivnuts) on the back of any cabinet and also screwed everything we could to the floor. Many of the screws went through plywood into wood stringers that were glued to the floor.

The only thing that broke free in our accident was the free standing galley and it separated in the middle, not the pieces screwed to the floor.

With competent construction and your bulkhead I wouldn’t be at all worried for you. If your cats are roaming free (as our dogs were) that is a different matter and only you can decide how much you want to restrict their freedom to protect them in an accident.
 

·
Registered
Joined
·
1,400 Posts
Hi ES

To anchor our build down;

Our floor is 3/4” plywood (the largest sheet is a 5’ x 10’)bolted thru the metal floor with more than 30 8mm bolts

our cabinets & bed are made from 3/4” plywood, aluminum angle, & steel angle drilled and bolted together forming box beam type structures

we have some gables 5/8” plywood that are scribed tight to floor & ceiling & wall

many rivnuts 1/4” & 3/8”

most items in our upper storage cabinets are light (clothes etc)

I have several photos on my build thread
 

·
Registered
Joined
·
259 Posts
Powder hounds, what was the construction of the cabinet that failed?
It was a self built galley cabinet, mostly free-standing in the slider door opening. Floor was 1/2” or 3/4” Baltic birch. Sides were 1/2” Baltic birch. Middle divider was 3/4”. Countertop was 3/4” zebra wood. Everything held together with brad nails and tite bond III. It was screwed down to the floor through plywood and wooden stringers glued to floor with plenty of screws. The right side of the galley was also bolted to the pillar behind the rear door. Lots of drawers filled with heavy kitchen items and dog food.

B25909D2-D581-44AC-97E5-408E3FADA67B.jpeg

CED038E9-9BCB-4947-8B16-BFEE28A42F12.jpeg

427AE72D-C5DD-4C44-AB46-CC448AA9BBA2.jpeg

Anyway, the failure mode was the cabinet itself breaking in half. Anything screwed or bolted to the van stayed put.

Crash pic. See how the entire cabinet broke in the middle and shifted forward. The right side (left in the picture) stayed bolted to the wall and the cabinet next to it on the inside. The bottom stayed screwed to the floor. The left side of the cabinet, pulling the top drawers, ripped apart and slid forward to the passenger seat. There was no effect on the passenger seat. I suspect the cabinet breaking absorbed a lot of energy. Again, this was a 62 mph front left corner impact into a ditch with just a little extra sliding in the ditch after impact.

EA193CAE-C656-4A4C-B38B-35A0223136ED.jpeg
 
  • Like
Reactions: phil

·
Premium Member
Joined
·
8,669 Posts
Powderhunds thanks so much for posting this. I really appreciate it.

I’d venture the guess that the failure of that cabinet was due to a lack of horizontal panels. It is all drawers and doors with just vertical support. Not to criticize but just to evaluate.
WaterStorage.JPG GalleyOut.jpg
Here is my galley to compare. I removed the refrigerator in the garage picture. Missing are pictures of the interior horizontal dividers that back the water jugs. and a picture of the bolts into the van’s pillar. Notice the cabinet extends down through the plywood floor and is bolted down in two additional places. Your cabinet failure is from racking and mine might too but the plywood box with cutout doors leaves more horizontal material to resist racking. My refrigerator filled, probably weighs 60 lbs as the fridge itself is 49#. In a 10 G collision the force of just the fridge would be about 600 #. A total frontal collision into an immovable object can be up to nearly 30G and probably not survivable for occupants anyway.
 

·
Registered
Joined
·
259 Posts
It’s tough to describe the rest of my cabinets because they are all very different. Behind the driver’s seat was my electrical box. Screwed down and bolted with approx 5 bolts to plus nuts.
466A19CA-68DF-4181-B4DD-5739100F5FD7.jpeg

Next to the electrical box was a wardrobe. The wardrobe was really just two vertical 3/4” Baltic birch pieces. I made cross braces in the back and those cross braces each had two plus nuts to the wall. There were probably three cross braces. The cross braces were just screwed into the edge of the uprights, maybe also glued. I’m not finding any good pictures of the wardrobe but it was pretty basic.

Example of wardrobe cross brace.
637CF3F8-E9C2-4732-9CA0-53B6AE45273B.jpeg

Behind the wardrobe was our fridge, drawer, microwave, and cupboard on top. It was built in a couple pieces, but all glued and screwed together and bolted in multiple places to the wall.

CA8B6402-1975-4C2E-9429-5DD8F445D589.jpeg

Behind the galley that broke free was a pretty box that housed the toilet. The other wall was the galley. Angled screwthrough the floor and bolted to the wall.

60087


Behind the toilet was a 25 gallon water tank built on top of the wheel well.

8BA16A12-9B1E-4385-88F7-0CA7247AF3F9.jpeg

The bed was an 80/20 frame built on 6 legs that went down and attached to custom brackets that attached to the d-ring bolts.Above our bed we had fairly lightweight dividers with baskets for clothes.

6CADB5A6-00F0-4A20-B095-98F88F588A01.jpeg

Of all this, the galley was the only thing that moved. The battery cabinet lid twisted. The bed moved forward an inch (it probably would have gone more but was stopped by the fridge cabinet). The solar panels and fridge were still humming the next day when we went to the tow yard.
 

·
Registered
Joined
·
259 Posts
Powderhunds thanks so much for posting this. I really appreciate it.

I’d venture the guess that the failure of that cabinet was due to a lack of horizontal panels. It is all drawers and doors with just vertical support. Not to criticize but just to evaluate.
View attachment 60065 View attachment 60066
Here is my galley to compare. I removed the refrigerator in the garage picture. Missing are pictures of the interior horizontal dividers that back the water jugs. and a picture of the bolts into the van’s pillar. Notice the cabinet extends down through the plywood floor and is bolted down in two additional places. Your cabinet failure is from racking and mine might too but the plywood box with cutout doors leaves more horizontal material to resist racking. My refrigerator filled, probably weighs 60 lbs as the fridge itself is 49#. In a 10 G collision the force of just the fridge would be about 600 #. A total frontal collision into an immovable object can be up to nearly 30G and probably not survivable for occupants anyway.
Probably right. The only horizontal piece was above the dog food drawer and was part of the half that broke free. The countertop was the only other horizontal stabilizer besides the drawers where it ripped out.
 

·
Premium Member
Joined
·
1,663 Posts
Powderhunds thanks so much for posting this. I really appreciate it.

I’d venture the guess that the failure of that cabinet was due to a lack of horizontal panels. It is all drawers and doors with just vertical support. Not to criticize but just to evaluate.
View attachment 60065 View attachment 60066
Here is my galley to compare. I removed the refrigerator in the garage picture. Missing are pictures of the interior horizontal dividers that back the water jugs. and a picture of the bolts into the van’s pillar. Notice the cabinet extends down through the plywood floor and is bolted down in two additional places. Your cabinet failure is from racking and mine might too but the plywood box with cutout doors leaves more horizontal material to resist racking. My refrigerator filled, probably weighs 60 lbs as the fridge itself is 49#. In a 10 G collision the force of just the fridge would be about 600 #. A total frontal collision into an immovable object can be up to nearly 30G and probably not survivable for occupants anyway.
Hi RD,
I looked into survival g loads a bit in a past life and found actual tests done by the military that showed that chimpanzees had a 50% survival rate at 50 g's (belted in) -- these tests were done years ago and I suppose would not be allowed now, but they are good data. I'd guess that a belted in person with air bags could survive more than 30 g.

Powerhunds crash is really useful data and a terrible thing to go through, but the fact that they walked away from it without serious injuries indicates that its the bottom end of what should be designed for.

Gary
 
Joined
·
37 Posts
We are at the start of our design and are looking for information about what people have done to minimize the effect of a rear-end or frontal collision, i.e, preventing the contents from flying forward into the driver and passenger. We have a few other questions, too!

1. Our biggest question is, what do (did) you do to ensure that your cupboards and their contents didn't come off the walls or floor if you got into a collision? How did you secure the drawers, where did you store sharp objects and tools for travel, where is your pet while you're driving? I've been researching the forces generated by as little as a 30-mph rear-end collision and am seriously concerned.

2. Our design includes a partition with a 20", windowed door opening toward the driver's seat. We want to enter and exit the van primarily via the passenger side door from the cab area (if you are curious, our reasons are below) and then into the living area through the partition door. Apart from having to duck and slide, is this realistic? What problems can we expect to encounter if we do this?

3. We're planning to convert a 159" high-roof. Will we be able to hang our two batteries, a 15-gallon water tant, and both a 15 gallon grey-water and 10-gallon black-water tank under the van floor? What are the pros and cons of doing this?

4. We're boaters, familiar with zip-up screening surrounding the cockpit of a boat. We'd like to use the same approach to screen the side sliding door area and the rear door area, with the zip coming down one side. Apart from the need to unzip the screen to get out, what problems or constraints can you see this introducing? We expect we'll have to use a marine place to do the design and install.

5. We will have one MaxxFan in the rear over the bed and one forward, near the partition. Because of this and because we plan to keep the the screened doors open in good weather, we're considering having only one of our windows open, the one over the kitchen area. The others would be fixed. Can you see any problems with this?

I've learned so much in the last few months lurking on this forum! Now that we're in the planning stages, I look forward to getting your views on our ideas. Thanks in advance for any responses!

WHY WE WANT TO USE THE DRIVING AREA DOORS and HAVE ZIP-UP SCREENS
Our two indoor-only cats will be travelling with us. They almost always hope to go walkabout and keeping them inside when we open the huge sliding door will be difficult. It will be impossible if we have magnet-based screen curtains. Hence, the two-stage entry and exit process (partition door and then passenger side cab door) and the heavy-duty zip-in screens.
1) I love Rivet Nuts for securing thing to the side of the van as I want to be able to quickly take things out if desired. The Rivet nuts the factory use are 8m so I decided to go with those, for the floor I threw bolt with big washers.

3) On my 1st van I installed the batteries under the rig which was a pain in the A.. but worked. However with that being said on my 2nd and now 3rd van I’ve decided to put them inside the rig.

5) My 1st van had 3 motion windows and one Fantastic which was perfect for the dog. It allowed cross breeze and the van stayed much cooler than I realized. The 2nd build only had one window and one Fantastic, the van was ALWAYS really hot!

We have found if you have a roof rack and have plywood or something attached to it to cover most of the roof, then the rig will stay much cooler due to the shadow it produces and blocking the sun. For this 3rd build I’m doing 3 motion windows and one CRL Window plus a MaxAir vent fan, will probably do racks where the solar is not on the van. My bed is elevated above the rear door entry point so my bunk windows in back can stay open without someone being able to reach in to open it. My CRL window that is behind the drivers door will have my cabinet in front of them so again it will be impossible for a hand to reach in to unlock the doors but one could use a tool to get around it, like a rock. I’m hopping the cross breeze will be enough with the two bunk windows open, the CRL window open and the roof vent open for our dog while we are doing things.

* Powder Hunds, wow, thanks for posting that! I’m going to overkill the securement on everything based on your thread.
 
1 - 20 of 23 Posts
Top