Project SAK (Swiss Army Knife)

[RoosterBooster]

i`m working on the details of my next Truck project that i hope to start building soon.

i figured i may run my ideas past you guys before i start drawing everything out in CAD;
so any comment, suggestion or critique is welcome

this project started as a mostly pavement "Towrig" to mainly haul my dogs and tow my vintage aluminum "aircraft style" trailers,
but thanks to this board i re-discovered my taste for going "off the beaten path" (i dont know if i should be glad or if i should curse all you guys lol)
so it evolved into a rough-/off-road capable, self supporting mini motorhome.

i have this project also posted on another board;
after my latest photochop a guy suggested that as a Swiss (born and raised in Switzerland so please excuse my bumpy English)
i should call my project the SAK due to its multi-purpose design...

so SAK it is

anyway, here is my latest Photochop;

my goal is to have large tires (~42"), excellent ground clearance and approach/ departure angles but still maintain a very low profile (10' max)
for aerodynamic, clearing objects (like tree branches) and low CofG.
after seeing the "Offroad Schmiede" Bremach with its wedge shaped pop-top camper here on this board i got inspired to design my own interpretation of a lightweight lifting roof ;

i usually dont like slideouts or any other gadgets that can (and usually do) fail ,
but i like this lifting roof for its simplicity and natural water shedding (overlapping) as well as its solid (no canvas) side wall design.
all it basically needs is a large SS piano hinge at the front, a single jackscrew lifting device (electric with manual override) and some well placed compression seals.

... more details to follow

 

[JWag21]

Rooster,
I wondered when you would start a thread over here. I enjoy reading your thread on the "other" site. Good luck with the build. I'm subscribed. You should get a lot of helpful advice/recommendations over here.

JWag21

 

[RoosterBooster]

thanks JWag21
yes, i can not even start to tell you how much that thread helped me to gather and finalize ideas.
if you think alone about a project you kinda go in circles , but if 100`s of brains throw in different ideas you end up with interesting new directions to explore.

here are a couple more details;

first and foremost this is a strict low budget project ...
the plan is to spend money where needed and elbow grease everywhere else.
dont expect to see a cool gadget collection on this truck: it will be very basic (think KISS!)
the truck will be optimized for relaxing long distance travel, excellent towing capacity, low fuel consumption as well as rough-/off-road ability for the "get away" trips.

i have two rotten spoiled, large and hairy "kids" ("Briards"; French sheep herding Dogs) and enjoy to compete with them in AKC Agility sport events...

my 4 year old "Ozzy"

and my 15 month old puppy "Armas"
... so we travel a lot (and usually dry-camp) all over the west.

the main purpose of hauling my dogs is demanding a couple things;
- engine independent rear AC (generator powered)
- lots of drinking water available
- lots of floorspace for them to stretch out and sleep on long trips.
- a quiet, save place so they travel relaxed and rested
- cold storage/fridge ; i feed my dogs "raw" (no pre-made food) so i need storage for lots of fresh meat/vegetable

some of my demands are;

- a fuel efficient real "Truck" engine ("wet sleeved" and intercooled inline 6 turbo diesel ) preferable "pre-emission"
- manual transmission (fuel efficient and KISS)
- air brakes (mainly for its engine driven air compressor/air supply)
- air ride rear suspension
- air ride driver seat
- easy to work on (conventional "tilt forward" truck hood... no cabovers)
- very large axles, brakes and tires (42" tall 22.5`ers)
- at least 120 gallon fuel capacity (i like to pick where and when i fill up)
- one permanent bed (no converting dinette) to take turns sleeping/relaxing on long trips
- permanent toilette (i guess i drink too much coffee )
- small kitchenette
- ...

more later...

 

[dzzz]

If you have the skills to build the top from an existing body it seems like the budget could be modest. Jack's truck 'Casa Azuel' has a cargo body like you show that's a little wider than most campers. That contributes to a more casual functional interior without the need to fill it with expensive cabinets.
With two wheel drive and 8' wide your less mobile, but there are cost and space advantages to that design. I wonder if you can find a short enough box truck with diesel and air. Those tend to almost always be the big CDL delivery trucks with a CA considerably more than you mockup.

 

[RoosterBooster]

If you have the skills to build the top from an existing body it seems like the budget could be modest. Jack's truck 'Casa Azuel' has a cargo body like you show that's a little wider than most campers. That contributes to a more casual functional interior without the need to fill it with expensive cabinets.
With two wheel drive and 8' wide your less mobile, but there are cost and space advantages to that design. I wonder if you can find a short enough box truck with diesel and air. Those tend to almost always be the big CDL delivery trucks with a CA considerably more than you mockup.

Don
yes, i have the skills and the tools to do the work myself
in fact i could build the box from all new material if i wanted to,
but to be honest i can not buy all the aluminum sheets, the aluminum extrusions, the cast aluminum front corner caps, the aluminum roof , the bonding glues , etc ... for the price that i can pick up a good used commercial dry van body.

the roof on the van body`s is usually a excellent design;
one piece roll aluminum bonded to the roof bows and riveted only to the parameter C-channel extrusion on the outside
this way there are no fasteners that penetrate the skin over the inside.
so my plan is to leave the roof area completely untouched and simply cut the upper part off at the right location.

shortening a box is not a big problem; i dont need the (very heavy) rear frame/rolldoor anyway so i`m actually looking to buy a long box (if possible a standard 24 foot) and cut it down to the ~15 feet i need.
this way i end up with excess material to build/permanently enclose the rear wall.

however, the "overlap" wall (that gets exposed when the roof is lifted) will need to be fresh material so that i can bend the sheets in shape for a correct "water shedding" overlap to the lower wall.
unfortunately the stock floor will be scrap;
it is usually excessive heavy & strong (build for high area pressure like fork lifts and palette jacks)
and due to the need for a torsion free 3-point mounting of the box i just have to build the complete floor structure from scratch.

the base truck is basically the same story;
i will be shopping for a truck that is at least the WB i need or (preferable) longer.
shortening a WB and/or a frame is easy (but i would never dare to extend a frame :Wow1
i already have a complete air suspension (a mostly forged aluminum Peterbilt "Air-Leaf" that i have left over from converting my Pete to single rear axle)
MDTrucks are usually geared way too short (mainly spec`ed for city delivery)
so instead of swapping the 3th member (gears) i plan to simply exchange the complete axle for a "highway" geared unit (with air locking diff )

availability of air brakes on a non-CDL truck depends on the county (some outlaw it, some dont )...
on used trucks here in the west the split of air and squirt brakes is roughly 50:50.

registering a air brake non-CDL truck as an RV is usually not a problem (if it is converted to meet all the other "RV" requirements)

as a side note;
California is getting a new emission law in 2012 eek ... so right now there are many good (rust free) used trucks on the market that beg to be exported to AZ :victory:

 

[RoosterBooster]

Here is a rough sketch of the chassis with a torsion free mounting idea (the two rear sets of rubber bushings are on pivoting trunnions)
however, the cab is wrong (it is the newer generation navistar truck, but that was all i could find on IH`s body builder website)...

the tank layout is really the most difficult thing when planing a chassis...
i`m still shuffling things around a little but the basic idea is to use just about every space available in the frame to free up space in the box (and to keep the CofG low)

the capacity ;
- 60 gallon utility water (blue)
- 35 gallon shower + 15 gallon kitchenette grey water (i like to keep them in individual tanks)
- 30 gallon black water
- 20 gallon generator fuel (red)
- 2 medium LP bottles
- 155 gallon diesel (its big ... but i have that tank and the hangers left over from another truck so i will reuse it on this one)
- green is the generator (most likely a pre-electronic "low rpm" onan ... fairly quiet, simple & reliable)

i plan to run a single 5" stack with a smaller pipe hidden behind it for the generator.

to keep the rig short (under 25 feet) i plan to have the spare tire recessed into the backwall (that will also keep it out of the sun).

and here is a sketch of the floorplan (i used a Sportsmobile floorplan and tweaked it into my application):

nothing fancy ; a 42 x 42 shower/ toilette , 36 x 80 bed/seating (that covers the bump in the floor from the high mounted diesel tank) ,
the rest is kitchenette/storage.
i dont like roof mounted AC`s so i plan to mount a wall unit over the spare tire recess

 

[RoosterBooster]

my focus is on a International 4700/4900 with the DT466 inline 6 for several reasons;

the main reason is that i already owned one some 10 years ago and made ~100000 miles with it with hardly any trouble.
IIRC i was stranded two times; one broken air regulator at the brake air compressor and a stuck tank equalizer valve (this is the reason why i now rather have one big tank then a dual setup lol )...

many of the miles have been on dirt/desert roads as well as towing a trailer with a 4x4 or Truggy on it ...

it is/was the best selling MDT truck in America for decades.
the DT466 engine is a "wet sleeve" design that can be rebuild "in frame" . if possible i will look for a P-pump (mechanical injector) model without ECM ...
however, the later ECM/E-injector models have also the reputation to be highly reliable.

i loved that truck ... but i made many mistakes that i try to avoid this time.
the biggest mistake was its size;
at 31' long , 102 wide and 12.5' tall it was just too big.
one focus will also be to "clean up" the belly to a ~20" ground clearance as well as a 45+ degree approach and a 30+ degree departure angle.
the truck was also nose heavy (what is a bad thing on a RWD ) so this time i will pay close attention to a correct weight distribution.
going smaller(lighter) has also the advantage that the dual rears are not needed. they trap and throw rocks and have a high rolling resistance in soft ground.

i believe with a good weight balance, high ground clearance, change to traction single rears , free flexing frame, comfortable suspension, air locker and low CofG the truck will offer a decent high rough/off-road capability without the cost , weight and raised CofG penalty of a 4x4 conversion.

 

[Overland Hadley]

:lurk:

 

[RoosterBooster]

i was very busy with work and traveling so i still didnt have time to start the 3D CAD drawing ...

but i had plenty of time to think some more about the layout and discovered a couple mistakes like that the generator was on the wrong side (the outdoor kitchen/sitting side)
i also moved the door all the way to the rear corner to avoid eventual noise/draft problems when traveling.
by squeezing things a little tighter i was also able to shorten the rig by almost another foot (i`m now at under 24feet / 7.3 meter) and found some better sized tanks
(i try to stick with "off the shelve" products to avoid the "custom made" expense)
tank capacity grew a little;
i have now 75 gallon fresh, 50 gallon grey, 30 gallon black and 40 gallon fuel (the large fuel tank will also be handy to may carry extra fuel for the ATV`s)
diesel is still the same 155 gallon tank.

anyway, here is my newest sketch ;

for simplicity i also decided to probably skip the "popup top" idea.
building a simple "fixed height" box is just a lot more economical, lighter and structurally stronger.
here is the passenger side view;

as i already mentioned the rig will mainly be used as a high mobile towrig that is carrying all the heavy stuff (generator, fuel, fridge, shower, toilette, water,...)
i`m custom building/restoring a trailer that will be dedicated to supplement this rig.
the trailer will be kind of a base camp with large and comfortable beds, room for two ATV`s , but with only very minimal other features (a small kitchenette and another toilette)
the trailer is based on a restored/customized 28 foot vintage aluminum "Spartanette" that was build by Spartan Aircraft Corp. in Tulsa OK in 1950 :ylsmoke:
its a giant teardrop shape and actually has a very good ground clearance and departure angle.
here is a link to a nicely restored 1952 model that is very similar in shape :http://www.flytecamp.com/Flyte_Camp/For_Sale/Pages/1952_Spartanette_For_Sale.html
(unfortunately my trailer was already gutted on the inside and had too much damage to be restored back into original)

 

[RAKY0311]

I like you plan,what kind of MPG are you expecting?

 

[Entropy]

for simplicity i also decided to probably skip the "popup top" idea.
building a simple "fixed height" box is just a lot more economical, lighter and structurally stronger.
here is the passenger side view;

Aww, I was really looking forward to that since I'm considering some kind of pop-top system myself. Looks like a great rig though and I'll be following the build closely!