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'wittle 'wesistor (Mini Jeep)

17061 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."

https://en.wikipedia.org/wiki/Jeep

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

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

Wheel Tire Wood Font Rectangle
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Mini-Jeep Grille with Head lights & Marker Lights
Automotive lighting Grille Automotive tire Hood Wood

Another angle/view
Automotive parking light Automotive lighting Motor vehicle Hood Automotive design

The back side
Grille Automotive parking light Automotive lighting Hood Automotive tire

Another angle/view
Automotive parking light Grille Automotive lighting Motor vehicle Hood
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The phone dial LED headlamps ruin the authenticity, imo.

If they're plastic lens covers, I'd sand them, or hit them with solvent, to hide the LEDs.
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The phone dial LED headlamps ruin the authenticity, imo.

If they're plastic lens covers, I'd sand them, or hit them with solvent, to hide the LEDs.
The backstory or narrative is a guy bought a surplus military Jeep
...to use as a personal vehicle (Civilian Jeep AKA as a Jeep CJ) ;)
...& then, customized it

So, everything that can be customized
...may be customized
...&/or updated (like LED lights, here in 2023)

I like 'em
...so, hopefully they "grow on you" too :)

Also, got rid of them old/original wheels
...& gots some updated Mini-Jeep wheels
Tire Wheel Automotive tire Tread Synthetic rubber

Updated them old/original Mini-Jeep hubs & bearings too
Tire Wheel Automotive tire Tread Synthetic rubber
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Motor-vation parts
Shipping box Wood Table Box Plastic

(2) Unite My-1020 48V 1,000W (~1.2HP) brushed motors
Liquid Bottle Fluid Glass bottle Drink

(2) XK-10-E1F-31 48V 31A Speed Controllers
Circuit component Electrical wiring Gas Electrical supply Technology

These XK-31 speed controllers are physically quite a bit bigger than a standard YK-31 48V 1,000 speed controller
...& listed as 31A (up from 28A of a YK-31)
Circuit component Electrical wiring Hardware programmer Gas Cable

Here is the wiring definition
Gesture Font Material property Parallel Pattern
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I made a bracket to mount the (2) SC(s)
...& a tray to hold them, the wiring & the connections ;)
Wood Gas Table Automotive exterior Automotive wheel system

Wood Table Motor vehicle Gas Machine

Now, I'm working on the wiring

I plan on including fuses in all of the power circuits (Brake Light, Head Lights & Charge Port)
...but, should there be a fuse in signal circuits, like the Brake Light switch circuit?
...or in the Reverse switch circuit?
...or the (3) speed switch circuit?

* All circuits operate at (48V) pack voltage (except for the (5V) Throttle)
Handwriting Font Circuit component Electrical wiring Gas
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I harvested the fuse box out of an old Isuzu NPR truck
Circuit component Electrical wiring Electricity Gas Electrical supply

Then, surgically removed a section that has the capacity for (10) fused circuits
Circuit component Wood Electronic component Passive circuit component Electronic engineering

Back side
Automotive lighting Red Electrical wiring Wood Automotive exterior

The "small" power circuits (Headlights, Brake Lights etc.) on this vehicle, all operate at pack Voltage ~50V
...but, will probably carry less than an Amp

* Except for the Charge Port, which is also pack voltage (~50V)
...but, it may have to convey up to (10) Amps
...so, it will have its own separate & proper fuse

So, can a 12VDC automotive "type" fuse box handle ~50VDC at (~1) Amp?
...& maybe using the "small" (3 - 5A) fuses?

The idea is to provide some sort of Direct Short protection between these "small power" functions
...& that (2kWh) batt pack

** Which most go karts &/or small parade vehicles don't usually have
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littlefuse has some 58Vmini blade fuses, most 12V fuses are rated 32V
later floyd
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Yeah - I wouldn't use 12V on a 50VDC circuit, unless you enjoy bonfires.

Good find @floydr ...got any 600VDC mini blades 😈 ?
littlefuse has some 58Vmini blade fuses, most 12V fuses are rated 32V
later floyd
Hey Floyd,
Thanks for the "tip" :)

I found these 58VDC 2A Blade fuses on Amazon (~$2.50 ea.)
https://www.amazon.com/Littelfuse-Auto-Blade-Fuse-58V/dp/B07KXGWVJL

Any idea why the rating, for 12VDC fuses, would "stop" at 32V?

I've noticed that a lot of electrical components in the "Marine" industry are rated ~48VDC
...& ~60VDC seems to be the "cut-off point" for many EV regulations

Yeah - I wouldn't use 12V on a 50VDC circuit, unless you enjoy bonfires.
Well, I do enjoy a good Bon-fire every now & then ;)
...but, not in, around, or any where near my Mini-Jeep
...so, can you please explain a bit further?

Like, in the case of a direct short, on a ~48V & ~1A circuit, wouldn't a 12VDC 3A fuse still simply "blow" or fail?
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One thing I thought of in my two hour drive just now - if the mini blades are pin-compatible between the voltage ratings, there's a future problem possible if someone does swap in a 12V. You'll need to at least placard the fusebox if so.
Any idea why the rating, for 12VDC fuses, would "stop" at 32V?
32VDC is the arc stopping rating. In other words The arc might still complete the circuit even if the fuse is blown leading to possible fire , damaged electrical components, etc.
Just like Circuit breakers are rated for voltages as well as in amps.
later floyd
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32VDC is the arc stopping rating. In other words The arc might still complete the circuit even if the fuse is blown leading to possible fire , damaged electrical components, etc.
Just like Circuit breakers are rated for voltages as well as in amps.
later floyd
Hey Floyd,
I'm going to admit, that I have been using regular Automotive style Blade fuses in my (24VDC, 36VDC, 48VDC & even 60VDC) electrical projects for years & years
...& I have "blown" many, many of these fuses (over them years)
...without any catastrophic events (just a blown fuse)
...& never noticed any excessive heat or any melting of the fuse housing or holder)

For example, my ElTurbo kart (2017) was equipped with a (24VDC) system (speed controller & motor)
...but, I installed a (3rd) 12V battery
...so, I could overvolt the motor to (36VDC) at the "flick of a switch" (basically, electric Nitrus) :cool:

While testing, I kept blowing the 12V Automotive blade style fuses (30A & 40A)
...so, I made up a dual fuse holder
...& installed (2) 12V 30A fuses, to create a 60A fuse :p

*According to the meter, when the "Electric Nitrus System" was activated, the systems Peak Draw was ~100A :eek:
**This was only a test & that system has since been dismantled (y)

It was a great learning experience (I love it when a plan comes together)
...& Super Fun (exhilarating)
...but, now I'm wondering how did I or have I been "getting away with it"? :unsure:

So, what is a fuse?
FWIU It's a safety device. A replaceable "weakest link" in an electrical circuit, designed to fail, if a fault occurs.

What happens when/if the fuse is not the weakest link in an electrical circuit?
FWIU Then, the "next weakest link", in the circuit, becomes the "fuse" (like a connection/connector, a wire or even a component)

So, how do you make sure the fuse is the weakest link in the circuit?
FWIU The most important thing is to not oversize the fuse (Amperage rating)

What happens if the fuse is undersized for the circuit?
FWIU The fuse will not be able to carry the required current & will fail (or blow)

So, I've been doing some looking into these Automotive Blade style fuses (more self-inflicted research/learning) ;)

There seem to be (3) different sizes of these Blade style fuses
...Mini-Blade fuses (10.9mm W)
...Blade fuses (19mm W)
...& Maxi-Blade fuses (29.2mm W)
&
All (3) sizes seem to be available in (2) different Voltage ratings
...32VDC
...& 58VDC
&
Both Voltage ratings are available in a wide selection of different Amperage ratings
...500mA
thru
...40A

But, looking into it further, I've noticed that there also, seem to be many similarities between the 32VDC & the 58VDC Blade fuses like
...they both have an Interrupt rating of 1,000A (at their listed Voltage rating)
...they both list PA66 Housings (with a) Flammability rating- V2
...they both seem to have the same Time-Current charastics
...they both have an operating temp range of (-40*C - 125*C)
...& both have Zinc Alloy terminals
...but, I did notice that the terminals on most of the 32V rated fuses are tin plated
...& the terminals on most 58V rated fuses are Silver plated)

Inconclusive? :confused:
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As was stated, the design of the arc break is different to achieve current interruption within the rated time for the fuse to open.
Two parallel fuses of 30A do not necessarily give you a 60A fuse. It gives you a <60A fuse and likely a longer circuit opening time.

Not good practice.
As was stated, the design of the arc break is different to achieve current interruption within the rated time for the fuse to open.
Hey Remy,
Your responses don't address the question "how have I been "getting away with it?"

Here are (2) of the fuses that I compared

LittleFuse Series 297 Automotive Mini-Blade Fuse

MINI® 32V automotive blade fuses’ miniature design allows automakers to pack more circuit protection into less space. Despite their light weight, MINI fuses perform reliably in adverse environments and at extreme temperatures.

Features
  • Fast-acting
  • Available with ampere ratings of 2 A to 30 A
  • Interrupting ratings of 1 kA at 32 V dc
  • Operate at up to 125 °C
  • Tin-plated zinc alloy terminals
  • PA66 housing with UL flammability ratings of V-2
  • Net weight 0.57 g ±5 % per fuse
  • Comply with SAE J2077 and ISO 8820-3
  • UL Listed
  • Certified lead-free and RoHS compliant
MINI - Littelfuse

LittleFuse Series 997 Mini-Blade Fuse
MINI® Blade Fuses Rated 58V
MINI® style fuse for use in 42V Systems. Same Time-Current characteristic as the 32V MINI®
fuse. Fits into standard MINI® fuse sockets. Has a rejection feature to prevent fuses with
lower voltage rating from being wrongfully inserted into the circuit. Current rating 2A - 30A
@58 VDC max.

Specifications
Interrupting Rating: 1000A @ 58 VDC
Voltage Rating: 58 VDC
*Component Level Temperature Range: -40˚C to +125˚C
**System Level Temperature Range: -40˚C to +105˚C
105°C is a typical system level temperature requirement.
Terminals: Ag plated zinc alloy
Housing Materials: PA66
Complies with: SAE J2077
https://www.digikey.com/htmldatashe...prd-&msclkid=457e4830bfbc1ad3c3f22c6e8149a3b0
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FYI: while playing around with this concept (~5 years ago), I "blew" a lot of these fuses (excuse my profanity AKA excited utterance) in both the 24V & 36V circuits
So, this was not just a one time event
...the fuses just kept "blowing" the fusible element out
...& this was while under (or trying to supply) a very heavy load (the motor connected directly to the battery pack via a set of contactors)
&
I was rigorously looking for any heating &/or melting, of just about everything associated with the system.
Yes, of course you can "get away with it" - like with all sloppy practice, but it can bite you in the ass someday.

You never should go outside device ratings on safety items. Nor should you apply them in unintended ways (fuses in parallel). It's negligent if you're aware you did.

It's all fine until it's not.
Yes, of course you can "get away with it" - like with all sloppy practice, but it can bite you in the ass someday.

You never should go outside device ratings on safety items. Nor should you apply them in unintended ways (fuses in parallel). It's negligent if you're aware you did.

It's all fine until it's not.
The question was & still is "how did I get away with it"
...not "can I get away with it"

I already showed (& admitted) that I did & have been using 12V automotive blade style fuses for years :eek:
...& what the outcome was over & over & over (many, many, many times)
...which (actually) is collateral info that just occured

I wasn't using inappropriate equipment on purpose FWIU the voltage rating for most automotive wire (used on 12VDC circuits) was usually ~600VDC
...& the amperage rating varied, depending on the size of the wire (or conductor)
...so, I guess I (wrongly) assumed that automotive fuses were rated similarly :oops:

Now, I'm interested to learn more about why (why, why, why) :unsure:
...I don't want to argue about it
...I just want to learn more about it

Did you watch any of the videos?
They clearly show several of those 12VDC 30A (& even a couple of 40A) Automotive Blade style fuses "blowing" while under a very heavy load (up to 100A)
...& it seems to me that "if" there was going to be a catastrophic failure, there was plenty of opportunities for it to occur
...so, why didn't it happen?... even once?

Negligent?, at the time (2017) this DIY'er thought he was "doing good" just by using DC rated stuff :p
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Moving right along
...&/or on with the Show :)

I added a couple of cross members to support & secure the floorboard
...a steering column brace
...& a good-n-strong hood hinge mounting bracket ;)
Table Wood Outdoor furniture Chair Gas

Then, got the rest of the frame all welded up good-n-solid
...all cleaned up
...& in primer
Grass Wood Composite material Landscape Groundcover

...& then, blackened :cool:
Grass Gas Cooking Metal Composite material

Along with some other stuff too :p
Vertebrate Building Mammal Land lot Grass
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