2020 - Excalibur Electric Racing kart

[Functional Artist]

I aligned the floor board within the frame rails
…& then, used the "tabs" (as guides) to drill some (1/4") holes

Then, simply bolted 'er on

* May be able to angle the "wings" (extended front/side edges) "up" a bit, to add some extra stability
...but, this floor board actually feels pretty stable already
…& the pedals "function" well too

Next up, pedal "linkages"

 

[Functional Artist]

Been thinkin' about & workin' on the throttle linkage

I measured, the thumb throttle (that Ima gonna use) seems to have ~1" of travel or "throw"
...so, this way we know what we need for "pedal travel"

I made up a spring loaded "slide stop"
...but, IDK just, not "feelin' it"
Still thinkin'
…& bouncin' ideas

 

[Functional Artist]

While thinkin' about the throttle linkage, I figured I would get my HF 30" sheet metal bender out
...to "angle" the "wings" (of the floor board) up a bit

Mainly, to see how it could/would affect the "routing" of (both throttle & brake) linkages
...but, also to see how much it "stiffened" the front area, of the floor board
(yup, a noticeable increase in "stiffness")


While I had 'er out, I figured I'd bend up some "battery trays" too

I was able to cut (1) "blank" out of the "scrap", left from making the floor board
…& then, I cut a couple more, out of another old sign that I had in storage


Technical note:
I think it would be "best" to NOT let these batteries "hang" lower than the chassis
(as to NOT/NEVER be able to scrape on the ground)

So, I'm thinkin' that these "trays" should be only ~1" deep
…& they'll need a ~1' "lip" (for mounting)

* The (12V 12AH) batteries, that I'm using for the initial tests are ~4" wide x ~6" long
…so, (2) of them "end to end" would be ~4" wide x ~12" long

As such, these "tray blanks" needed to be ~12" x 8" wide
…1" (lip) x 1" (side) x 4" (bottom) x 1" (side) x 1" (lip)

But, this design, presented a new problem
...how to put (2) "opposing" 90* bends 1" apart from each other
...as my bender has ~3" "bending plates" on both sides

 

[Functional Artist]

I thought about "modifying" my bender
...but, no not really a good idea

Then, I thought maybe, I can make a "clone" of it
(it's a pretty simple design & doesn't seem like it would be that complicated)
...but, a bit smaller, "lighter duty" & to my specifications

It looks like the most important thing is to make sure the "pivot" is right in the middle of the plates

So, I rounded up some angle iron
…& went to measurin' markin', cuttin' & weldin'

It seemed to come out pretty good

Now, we'll see if it works
…&/or for how long

The last pic is of the (2) benders "back to back"

 

[Flyinhillbilly]

Of course my bias is toward race karts, but I have to say that I like this one very much.
You’re doing a nice job, and it’s looking great.

 

[Functional Artist]

Of course my bias is toward race karts, but I have to say that I like this one very much.
You’re doing a nice job, and it’s looking great.

Thanks

This is my first endeavor into the racing "style" kart world
…& I'm really enjoyin' the "challenges"

I can't wait to "start the engine"

Um, wait, "we" don't do that around here

I mean, testin', yea testin', I can't wait to start testin' 'er

* Makin' "specialty" tools certainly slow things down :toetap05:
...but, enjoyin' them "challenges" too

 

[Functional Artist]

Battery trays

I used my "new" bender to bend up some battery trays

They came out nice
...but, I had ta do some adjustin' to my measurements
...because, a "tray" with a 1" depth still sits too low (duh)

The pipe that I made the frame out of is 7/8" OD
…& as such, (1") "sides & mounting "lips" are a bit too wide

Also, the "bottom" was a bit too wide too
(I want 'em to kinda "snug" the batteries)

Luckily I made "my" bender with a 3/4" capability

So, I gotta cut some "new" blanks @ 6 7/8" x 12"
…& then, bent 'em @ 3/4" (lip) x 3/4" (side) x 3 7/8" (bottom) x 3/4" (side) x 3/4" (lip)

 

[Functional Artist]

I made up a few more battery "trays"
...just playin' with my "new" toy, I mean practice, I was practicin'

Goin' with the 3/4" "spacing" makes it so easy

Simply, insert the "blank", "aligned" with the edge of the "bending plate" & lift the lever
...then, pull 'er out & flip 'er over
...& then, "align" the bend with the edge of the "bending plate" & lift the lever again

Then, turn the "blank" around (360*) & repeat the procedure

 

[gegcorp2012]

Nice work on the bender and the tray.

Are you going to weld on some 90* angle to the ends or notch and bend the ends somehow ?

Sent from my SM-J700T using Tapatalk

 

[landuse]

I love the bender!!!!! Good job FA

 

[Functional Artist]

Thanks guys

I don't think puttin' ends on the battery "trays" should be necessary
...as the frame should provide enough support (to hold 'em in place)
...& also, protection (from both the ground & side impacts) for the front & rear of the batteries

A (2) sided battery "tray" (kinda like mine) is how many riding lawn mowers "mount/support" the battery

MTD Yard Machine's for example, mount their batteries up under the seat, in a (2) sided "sleeve"
…& suspend 'em right above the trans axle's "spinnin" input pulley

I just made 'em a bit "shallower"

 

[Functional Artist]

Brakes

For the Brakes Ima gonna use a standard 4" band "style" brake w/drum

* I know it's NOT up to par for "racing"
...but, I already have all of the components
…& we can easily "up grade" 'er later

Next, I guess we gonna need a "connectin' rod"

It's gonna need some custom bends (to follow the contours of the frame)
...but, we gotta keep 'em kinda "gentle" too

So, here is what I came up with

A 3/8 rod with a 90* bend (to connect @ the pedal)
...then, it has a connecting/adjustment "nut"
...then, it goes thru a "guide"
...then, it "kicks" outward
...then, it "kicks" back inward (so, it's back "in line" with the front section)
...then, it goes thru another "guide" tube
...then, it "kicks" upward (just a bit) to "line up" with & connect to the brake band

* Slides pretty smooth

Now, I gotta make a connector
...to connect the brake rod to the brake band

 

[Functional Artist]

To connect the brake band with the brake rod, Ima gonna simply use a piece of steel with a 3/8" hole in it
...slid into a "slot" cut into the end of the rod
(kinda reminds me of an arrow)

* During "fittin'" it looked like it would be beneficial to "angle" the "end piece" up a bit

Hopefully this, helps to keep 'er from hangin/rubbin' on the brake drum
...which would be extremely annoyin'

Then, I simply "clamped" 'er in place with a pair of vise grips
…& welded 'er on (from the bottom side for a cleaner look)

* Don't know what I was thinkin'
...but, it "popped in my head" that it would be a good idea to "seal 'er up"

Then, while it was dryin', I thought, WTF
...the guide tubes are to be welded to the frame
…& I haven't welder 'er on yet
...but, I did "slide" 'em up so, I could paint up under 'em

 

[Functional Artist]

I tried/looked around for places to mount the thumb throttle (that Ima actually, hookin' to the throttle pedal)
...like along the frame rail (in front of the seat)
...up under the seat
…or even behind the seat
…& then, connect 'er to the pedal via a cable

But then, it seemed like I was "over-complicating" things

So then, I tried puttin' 'er
..."off to the side"
...right behind the pedal

It lines up nicely
&
I like it
…"short sweet & to the point"

So, I got a piece of pipe
...marked 'er (leaving a little extra for the "fish mouth")
…cut 'er

Next, I marked the area (where the piece is to be attached on the frame)
…& cleaned 'er up

Then, I clamped 'er on (at the marks)
…prepped the "patient" for weldin' (covered everything that I didn't want "spatter" on)
…& welded 'er on

 

[redflash]

The idea for a thumb throttle seems primative ( forgive me)
I bought a electronic gas pedal from "electric scooter parts" that wires directly to the electronic controller ( no cables , springs , or otherwise)
just a direct wire tht plugs into the controller box...i believe about $35.00forthe best one and itbolts directly to the floor board with no special welded brackets.....seems a simpler and less bulky option.

Da flash

 

[Functional Artist]

The idea for a thumb throttle seems primative ( forgive me)
I bought a electronic gas pedal from "electric scooter parts" that wires directly to the electronic controller ( no cables , springs , or otherwise)
just a direct wire tht plugs into the controller box...i believe about $35.00forthe best one and itbolts directly to the floor board with no special welded brackets.....seems a simpler and less bulky option.

Da flash

"Howdy redflash

Yup, your right using an electric pedal would be simpler
...but, with this kart, I'm goin for the "race kart" look
(like in the movie that I referenced @ the beginning of this thread)
…& IMO it would kinda "ruin" the look

* FYI, I'm using a kool electric pedal on my Lunar Rover kart
http://www.diygokarts.com/vb/showthread.php?t=42557

Surplus Center currently (he he electric pun) have them available for (~$30.00)
https://www.surpluscenter.com/Elect...lt-DC-Hall-Effect-Position-Sensor-11-3493.axd

Here is some info on them:
"FOOT PEDAL WITH 5 VDC HALL EFFECT PEDAL POSITION SENSOR
New takeoffs, some light superficial rust. Originally made for use in RAVEN brand electric mowers. Hall effect pedal position sensor outputs a 0-5 VDC signal based on pedal position; 5 VDC output when pedal fully depressed. Hall effect sensor can be removed revealing a 0.10" thick x 0.32" wide male tang that rotates up to 55 degrees as the pedal moves.
Plastic pedal, 8 gauge steel lower bracket. Three wire leads terminated with a six cavity electrical connector."

** The twist throttles, thumb throttles & electric pedals all use the same "Hall Effect" technology

I like to use these thumb throttles because their so universal
...Damien has one (for thumb use) mounted on the steering wheel
http://www.diygokarts.com/vb/showthread.php?t=40084
...my El Moto has one "tucked" up under the gas tank & is actuated via the "stock" motorcycle twist throttle
http://www.diygokarts.com/vb/showthread.php?t=37062
…& the Atom kart has one mounted on the side of the battery tray that's actuated via a pedal
http://www.diygokarts.com/vb/showthread.php?t=40167

 

[redflash]

cool

Da Flash

 

[Functional Artist]

I got the brake rod guides cleaned up
…& welded 'er on
…& also, welded the brake band "bracket" onto the bearing mount

Then, reassembled the brake system
…& gave 'er a try

Slides nicely, in the "guides'

Feels, good-n-firm
...actually, very firm (with no noticeable flexing of the connecting rod)
…& the pedal "travel" is only ~1"

 

[Brianator]

You're doing a great job, I can't wait to see the finished product!

 

[Functional Artist]

The Plan is to mount the thumb throttle onto the "stub"
...run a short piece of throttle cable (forward) to connect 'er, to the pedal
…& also, a small "return" spring (rearward) to connect 'er, to the frame

This spring 'll keep 'er 100% "off" (Zero throttle) when the pedal is not actuated
…& also, provide the "return action" for the pedal too

All pretty simple
...but, to get 'er all together, we gonna need a "custom connector", to connect the cable to the pedal

A little smoke
…a few mirrors
…& "Boom" we got a kool DIY cable to pedal connector