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'wittle 'wesistor (Mini Jeep)

16920 Views 296 Replies 7 Participants Last post by  Functional Artist
For my next creation, I've been thinking about building a go kart sized jeep (mini-Jeep)
...but first, here is some Jeep info.

"The Jeep marque has been headquartered in Toledo, Ohio, ever since Willys–Overland launched production of the first CJ or Civilian Jeep branded models there in 1945. Its replacement, the conceptually consistent Jeep Wrangler series, remains in production since 1986. With its solid axles and open top, the Wrangler is the Jeep model that is central to the brand's identity.

At least two Jeep models (the CJ-5 and the SJ Wagoneer) enjoyed extraordinary three-decade production runs of a single body generation.

In lowercase, the term "jeep" continues to be used as a generic term for vehicles inspired by the Jeep that are suitable for use on rough terrain. In Iceland, the word Jeppi (derived from Jeep) has been used since WWII and is still used for any type of SUV.

Prior to 1940 the term "jeep" had been used as U.S. Army slang for new recruits or vehicles, but the World War II "jeep" that went into production in 1941 specifically tied the name to this light military 4x4, arguably making them the oldest four-wheel drive mass-production vehicles now known as SUVs. The Jeep became the primary light 4-wheel-drive vehicle of the United States Armed Forces and the Allies during World War II, as well as the postwar period. The term became common worldwide in the wake of the war. Doug Stewart noted: "The spartan, cramped, and unstintingly functional jeep became the ubiquitous World War II four-wheeled personification of Yankee ingenuity and cocky, can-do determination." It is the precursor of subsequent generations of military light utility vehicles such as the Humvee, and inspired the creation of civilian analogs such as the original Series I Land Rover. Many Jeep variants serving similar military and civilian roles have since been designed in other nations.

Development – 1. Bantam Reconnaissance Car
When it became clear that the United States would be involved in the European theater of World War II, the Army contacted 135 companies to create working prototypes of a four-wheel drive reconnaissance car. Only two companies responded: American Bantam Car Company and Willys-Overland. The Army set a seemingly impossible deadline of 49 days to supply a working prototype. Willys asked for more time, but was refused. American Bantam had only a small staff with nobody to draft the vehicle plans, so chief engineer Harold Crist hired Karl Probst, a talented freelance designer from Detroit. After turning down Bantam's initial request, Probst responded to an Army request and began work on July 17, 1940, initially without salary.

Probst drafted the full plans in just two days for the Bantam prototype known as the BRC or Bantam Reconnaissance Car, working up a cost estimate the next day. Bantam's bid was submitted on July 22, complete with blueprints. Much of the vehicle could be assembled from off-the-shelf automotive parts, and custom four-wheel drivetrain components were to be supplied by Spicer. The hand-built prototype was completed in Butler, Pennsylvania and driven to Camp Holabird, Maryland on September 23 for Army testing. The vehicle met all the Army's criteria except engine torque.

Development – 2. Willys and Ford
The Army thought that the Bantam company lacked the production capacity to manufacture and deliver the required number of vehicles, so it supplied the Bantam design to Willys and Ford, and encouraged them to enhance the design. The resulting Ford "Pygmy" and Willys "Quad" prototypes looked very similar to the Bantam BRC prototype, and Spicer supplied very similar four-wheel drivetrain components to all three manufacturers.

1,500 of each model (Bantam BRC-40, Ford GP, and Willys MA) were built and extensively field-tested. After the weight specification was revised, Willys-Overland's chief engineer Delmar "Barney" Roos modified the design in order to use Willys's heavy but powerful "Go Devil" engine, and won the initial production contract. The Willys version became the standard jeep design, designated the model MB, and was built at their plant in Toledo, Ohio. The familiar pressed-metal Jeep grille was a Ford design feature and incorporated in the final design by the Army.

Because the US War Department required a large number of vehicles in a short time, Willys-Overland granted the US Government a non-exclusive license to allow another company to manufacture vehicles using Willys' specifications. The Army chose Ford as a second supplier, building Jeeps to the Willys' design. Willys supplied Ford with a complete set of plans and specifications. American Bantam, the creators of the first Jeep, built approximately 2,700 of them to the BRC-40 design, but spent the rest of the war building heavy-duty trailers for the Army.

Final production version jeeps built by Willys-Overland were the Model MB, while those built by Ford were the Model GPW (G = government vehicle, P = 80" wheelbase, W = Willys engine design). There were subtle differences between the two. The versions produced by Ford had every component (including bolt heads) marked with an "F", and early on Ford also stamped their name in large letters in their trademark script, embossed in the rear panel of their jeeps. Willys followed the Ford pattern by stamping 'Willys' into several body parts, but the U.S. government objected to this practice, and both parties stopped this in 1942.

The cost per vehicle trended upwards as the war continued from the price under the first contract from Willys at US$648.74 (Ford's was $782.59 per unit). Willys-Overland and Ford, under the direction of Charles E. Sorensen (vice-president of Ford during World War II), produced about 640,000 Jeeps.

Jeeps were used by every service of the U.S. military. An average of 145 were supplied to every Army infantry regiment. Jeeps were used for many purposes, including cable laying, Sawmilling, as firefighting pumpers, field ambulances, tractors, and, with suitable wheels, would run on railway tracks."

I came across this drawing
...& it seemed like a pretty good guide

So, I'm thinking maybe ~50% should work for a mini jeep, I'll just have to calculate a ~2:1 reduction ;)

Wheel Tire Wood Font Rectangle
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View attachment 136143
Now you need to wait 6 months before you can use that solar measuring table for 6"-spaced layout again.

Glad you got it done on the one of two days a year that you could 😂
That's what that workbench looked like last week (sunny & ~45*) :cool:
...& this week it's snowy & ~30* :(
Furniture Outdoor bench Snow Wood Outdoor furniture
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I did get the (2) bends installed, on the front section of floorboard (before the snow came) :)
Wood Rectangle Floor Flooring Composite material

...& also, dry fit, in the frame
Wood Bumper Automotive exterior Gas Motor vehicle

Another angle/view
Wood Flooring Hardwood Gas Composite material

* Multiple Bending Angle Dilemma
I decided to cut ALL of the side bolting flanges off of this front section (to simplify this piece)
...& will add bolting flanges to the side panels (for connecting the side panels to the floorboard) ;)

The top drawing shows the side panels without a (~1") bottom bent edge (bolting flange)
...just a bent (~1") front edge (bolting flange) & hood line
The bottom drawing includes full length, upper & lower (~1") bent edges

IMO adding (~1") bends, to the top & bottom edges, should make the side panels stiffer (stronger)
...& should also, end up making them smoother too (reducing waviness) (y)
Brown Handwriting Font Material property Rectangle
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Here is a pic, test fitting the CAD left side body panel (template) up to/with the steel floorboard

Seems "pretty tight" :)
Wood Flooring Floor Road surface Gas

So, (now) the "plan" is to have the bolting flange as part of, the side body panel
...& have it "tuck" up under the floorboard
...& then, secure the "junction" with a couple of nuts & bolts

Here's another view ;)
Wood Floor Font Gas Flooring
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Rear section of floorboard (Mechanical Drawing)
Rectangle Schematic Font Line Parallel

Rear section of floorboard (CAD)
Wood Rectangle Road surface Tints and shades Composite material

Rear section of floorboard (transferred to the steel)
Wood Tile flooring Rectangle Flooring Road surface

Rear section of floorboard (1/2 cut out)
* Used the straight edges & Vice Grips as a guide to help make straight cuts
Wood Floor Flooring Automotive tire Gas

Rear section of floorboard (100% cut out)
Wood Door Automotive exterior Composite material Flooring

Rear section of floorboard (cut out scraps)
* Yup, that's snow, on the right side of the pic
Road surface Asphalt Grey Wood Floor

Rear section of floorboard (manually installing the front bend) (Vice Grips X 6) ;)
* Bend orientation: upwards
Wood Floor Flooring Gas Composite material

Rear section of floorboard (not bad)
Wood Gas Bumper Automotive exterior Composite material

Rear section of floorboard (manually installed the mid-bend)
* Bend orientation: downwards
Wood Floor Automotive exterior Composite material Flooring
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You do know you can buy a bench brake for the cost of all those vise-grips?
I have & use Vice-Grips for a variety of clamping jobs (mock ups, welding etc.)
...but, hardly ever on/for nuts or bolts

* Unless the nut or bolt is/has been damaged
...& a standard socket or wrench won't work any longer

As far as benders, I have & use a DIY sheet metal bender, that can handle pieces up to ~25" wide (front of bench)
...& also, a HF sheet metal bender (up to ~30" W) (rear of bench)

I use them to make small parts (battery boxes, trays etc.)
...but, haven't had a need (so far) to bend larger pieces
Wood Bumper Automotive exterior Composite material Gas

The front edge, of the rear section, of floorboard is ~25" wide
...but then, quickly gets wider, just behind that
The area where the second (mid) bend goes, is ~34" wide
...& in the rear, where the third bend goes, is ~32" wide
A larger capacity bender would be nice
...but, I only need to make these (3) bends (that are "oversized" for my (current) benders)
I decided to "run what I brung"
...& just try to "wing it" (technical term) ;)

I think they turned out good
...or at least acceptable (y)
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Speaking of battery boxes:
Remy inadvertently brought up a valid point earlier, about battery box heat
...which got me to thinking about what else, inside of the box (besides the battery), can create heat

So, after re-evaluating the situation, it seems like "physically" mounting the SC's inside of the battery box, isn't a good idea
Because they can produce a lot of heat that can/will affect the battery
...& also, that "heat" isn't good on them either

As such, they would/could benefit from not being "sealed up in a box"
...& may even benefit from some cooling

* My main goal for this battery box is to secure the 2kWh of Lithium battery, in a steel box
...& then, secondarily to keep all of the (HV) battery cables & connections inside of the box

One of the earliest designs of the battery box, for this application, had the SC's (still) inside of the box
...but, off to the side
...& kinda like on a shelf (above the frame rail)
Handwriting Product Rectangle Font Material property

So, the plan ended up evolving to just a simpler (to make) (2) piece, (4) sided box
...& mount the (2) SC's inside of the box
...& also, mount the CB right onto the front of the box

This way all of the battery cables & connections, would stay inside of "the box" (with the battery pack)

Speaking of Circuit Breakers:
Here are some ideas on CB mounting mounting
...& a potential construction method

* That idea, was to have, the part of the box with the CB "butt" up against the floorboard the angled down area
...& in front of the seat

This way the CB could be "flush" (& even) with the floor board (by protruding thru a hole)
...& so, easily accessible by the driver
Handwriting Font Rectangle Wood Material property

But, "thinking it thru"
..."if" the CB was mounted "flush", with the floorboard (in front of & below the drivers seat) there seemed to be a "good" potential of "it" getting kicked during entry & exiting of the vehicle

So, it's probably NOT a good idea to have the CB "flush" with the floorboard
...& as such, "the plan" evolved to simply mounting the CB vertically (on the front of the battery box)
...& then, cutting an "access hole" in the floorboard

So, this way the CB would be safely mounted, down in a "recess" (& better protected)
...but, also, still easily accessible by the driver ;)

Oh, yea back to the SC's :p

So, now I'm thinking that I can mount the SC's on an actual "shelf"
...on the chassis, right next to the battery box (but, thermically isolated)

This way the wiring from the SC's can still "feed" right into the side of the box
...where all of the cables & connections should be safe & secure :cool:

Like this:
Wood Bumper Floor Hood Flooring

Another view:
Electronic instrument Audio equipment Automotive exterior Gas Hood

Checking for clearance, with a CAD side body panel
Wood Floor Automotive exterior Electrical wiring Gas

Double checking clearance with a CAD side panel & floorboard
Wood Bumper Automotive exterior Gas Metal
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I used some 1" x 1/2" steel channel, to make the body mounting brackets
...& they will also, help support the floorboards too ;)

The first (1) bracket will go under the lower section of floorboard (under the drivers feet)
...& will also, help support the seam, between the front & rear sections of floorboard

The second & third brackets will go under (& will also, be used for mounting) the seats

The last bracket will go under (& help support) the floorboard, under the cargo area
Wood Composite material Gas Metal Automotive exterior

Floorboards aligned & bolted together
...& bolted to the first mounting bracket too
Wood Automotive exterior Gas Roof Automotive wheel system

Side view
Wood Boats and boating--Equipment and supplies Automotive exterior Gas Bumper

The seam (connecting the front & rear sections of floorboard) looks nice-n-tight
Wood Road surface Automotive tire Floor Flooring

...& here is how it looks from underneath :)
Bumper Automotive exterior Automotive lighting Wood Gas
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Would be interesting to keep a log of the weight on this build.
Would be interesting to keep a log of the weight on this build.
Just the frame, with body mounting brackets, as seen here
Wood Composite material Gas Metal Automotive exterior

...& "stood up" on a scale
Table Wood Bumper Automotive exterior Gas looks like it comes in right at 46lbs. (so far) :)
Temperature Tints and shades Measuring instrument Display device Cyclocomputer
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Front & rear floorboard sections, come in at ~21 lbs.
Wood Measuring instrument Clock Hardwood Font

Seat(s) diagram
Rectangle Sleeve Font Pattern Wood

Seat(s) (bases)
Wood Table Gas Composite material Automotive exterior

Seat(s) (pass side dry fit)
Wood Outdoor furniture Gas Chair Composite material

Seat(s) (~36" from pedals to back of seat bottom)
Automotive tire Automotive exterior Gas Bumper Tool

Seat(s) (~10" from seat to steering wheel)
Automotive tire Tread Wood Road surface Chair

Seat(s) (~14" from seat back bottom to steering wheel)
Wood Automotive tire Bumper Floor Road surface
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Folding the passenger seat forward, or outright making it removable, might be useful for carrying stuff
Folding the passenger seat forward, or outright making it removable, might be useful for carrying stuff
I maintained the cargo area, for carrying "parade" stuff
...whereas most mini-Jeeps, fill that area with the seats

I am thinking about incorporating an access panel, under the drivers seat, the SC's & wiring & connections are (well) accessible :)

This way, if any issues arise, I (hopefully) won't have to "drop" the (~55lb.) battery box
... just for simple trouble shooting

Like checking/looking for a loose connection
...or even to be able to probe (the connections) for continuity &/or voltage ;)
Jeep owners come up with lots of interesting, kool & sometimes quirky sayings
...&/so, I'm going to share some of them with you'all ;)

Common answer for any Jeep related question:
"It's a Jeep thing, you wouldn't understand" :cool:

Bouncing around again
...but, that's kinda what ya do in a Jeep :p

I drew up a rear section of floorboard bending sequence diagram
It illustrates both the bending order & the direction of bend

Bends #1 & #2 are already done
Handwriting Rectangle Font Pattern Parallel

Bend #3 is actually (3) separate "pieces" (the tailgate & (2) 1" bolting flanges)
...& it "spans" ~32"

So, I used the edge of an old (solid) wooden door (workbench top)
...a piece of 3" x 3" x 1/4" angle iron (main hold down)
...a piece of 1" x 1" x 1/8" angle iron (bender)
...& a variety of C-clamps (main hold down clampers)
...& a few pairs of vice grips (bender clampers)
Bumper Automotive exterior Gas Composite material Wood

Then, tightened up & sharpened the edge of the bends with a Rubber Mallet :)
Hood Motor vehicle Automotive tire Fender Wood

Good enough for Jeep work :D
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"Don't follow me, you won't make it" :cool:

Bend #4 Left Inner Fender (prebend)
Motor vehicle Wood Automotive exterior Bumper Automotive tire

Bend #4 (post bend)
Table Wood Motor vehicle Automotive exterior Automotive tire

Another angle
Tool Bumper Automotive exterior Automotive tire Gas
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Making weekends more fun since 1941 :cool:

Same procedure for the Left Inner Fender
...& all of the 1" Bolting Flange(s)
Wood Automotive tire Bumper Automotive exterior Gas

Wood Bumper Automotive exterior Hardwood Gas

Getting "fancy" :p
Gas Space Art Darkness Metal

Last couple of bends
Table Wood Flooring Hardwood Automotive exterior

Ended up looking like this ;)
Wood Bumper Gas Rectangle Hardwood

Another view
Table Wood Bumper Automotive exterior Rectangle
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I like big Jeeps & I cannot lie :cool:

Rear section of floorboard, dry fit on the chassis (after bending)
Wood Bumper Gas Automotive exterior Composite material

Another view
Tire Wood Gas Vehicle Wheel

...& a view from underneath ;)
Wood Beam Tints and shades Gas Building
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No Boost or Bottle, Just Balls & Throttle :cool:

Real World Research: ;)

I towed a wrecked Jeep the other day, that had one of its front fenders "ripped" off
...& so, I examined how the body panels are connected in a FS (full size) Jeep
Wheel Tire Car Land vehicle Vehicle

A closer view
Wheel Tire Land vehicle Vehicle Car

Upon a closer examination, it looks like overlapping panels, that are just spot welded together)
Tire Wheel Automotive tire Motor vehicle Tread

In another area, it looks like there are 3 separate pieces, overlapped & then, spot welded
Tire Wheel Land vehicle Automotive tire Motor vehicle

Here it also, looks like 3 separate pieces overlapped & then, spot welded too
Tire Wheel Automotive tire Tread Synthetic rubber

So, I guess either Butt connections
...or Overlapped body panel connections will "work", depending on the situation ;)
Handwriting Rectangle Wood Font Parallel
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Those panels are glued and spot welded, which is why the low weld count.

That doubler and tripler sheet metal stuff is the controlled buckling design for crash energy absorption, and is also for deflecting the fused front wheel away from the passenger compartment - it is not really the kind of "structure" you are doing. There aren't any butt connections I can see - they are all laps.
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Jeep Math:
4 x 4 = OFF ROAD :cool:

I was specifically thinking about the Cowl to Side body panel junction
...& if this junction would be "better" if a standard body panel Butt connection was used
...or if just overlapping panels was used &/or acceptable, like this:
Wood Shipping box Flooring Floor Hardwood

Now, with (going to have) full length flange(s) on the body side panels, I could just add a 1" bolting flange to the Cowl
...& then, just bolt the (2) pieces together ;)
Wood Interior design Shelving Floor House
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