Torsk (Backbone Chassis) Kart

[Functional Artist]

A little artwork while I was thinkin'

I first contemplated using 4' round tube but, it seems like it would be easier to attach to flat surfaces
IDK it also just seems like round tube would twist more

Then, I was leaning toward 4" x 4" x 1/8" square tube (~6.5 lbs. per ft.)
But, the 12V 12AH batteries, being 4" wide, would not fit inside a 4" square tube (~3 3/4" ID.)

So, now I'm thinkin' 2" x 6" x 1/8" rectangular tube
...it's also ~6.5 lbs. per ft. (same as 4" x 4" square tube)
...but, I can cut out 4" (for the batteries) of the 6" wide tube & still have ~1" of steel wrap around to help maintain the "rigidity" of the backbone

Front Axle, could be made of 1" x 3" x 1/8" steel, ~18" wide
...proportionally reduced from the backbone dimensions (2" x 6" to 1" x 3")
I am thinkin' of leaving the axle as (1) piece, cutting 1" x 3" slots on each side of the backbone & running it right thru
...the left side axle stub would be 6", the backbone is 6" wide & the right side axle stub is 6" also (kinda of a 1:1:1 ratio)

Rear Axle Housing, could be made of 2" x 1/8" round tube ~14" wide
...it could cap off the rear end of the backbone

I am thinkin' of running the 1" axle thru it (like a true backbone chassis) & just having the bearings mounted right on the ends
...the left side axle housing would be 4", the backbone is (of course) 6" wide & the right side axle housing would be 4"
...the sprocket could be mounted between the bearing & the wheel, on one side
...& the brake rotor/drum on the other side

May do a mono-shock type suspension in the back

Still thinkin' on that one

 

[Functional Artist]

Got my order from BMI Karts this morning (just ordered Thursday that was quick)

I ordered some of the stuff that I usually don't or can't make myself

I asked about the DIYGK discount but, they said that they don't offer us a discount. (we need to work on that)

They still have the best deals, so...

ya, here's what I got

(1) Front spindle kit - (1) left & (1) right 4 1/2" x 5/8" (don't trust my weldin' skills that much)
(1) Rear Axle Bearing kit - for 1" axle (lighter than pillow blocks)
(1) Rear Axle - 1" x 32" with 1/4" full length key way (should be beefy enough for this concept)
(2) Lock Nuts - for 1" axle
(1) 12" of Key way stock - 1/4" x 1/4" (I should be able to cut all of the keys I need for this project) (1) for each rear wheel, (1) for the sprocket & (1) for the brake rotor/drum
(2) Rear Rims - 6" x 5" with a 1" bore & 1/4" key way

I also picked up (4) of these kool 10.5 x 4.5 x 6" Unilli "racing slicks" (they were on sale for ~$20.00 ea.)
Couldn't pass em' up

But, wow they are low rider's/ground huggers

What's up with these directional arrows?
...If all arrows are pointing forward, the kool yellow letters won't be facing outward on one side

 

[Functional Artist]

My order from Surplus Center came in today too

I got

(1) 1-piece 60T sprocket for #35 chain
https://www.surpluscenter.com/Brand...ional/60T-1-Bore-35P-Sprocket-1-2413-60-E.axd (~$25.00)

a (10') box of #35 chain https://www.surpluscenter.com/Power...-1-10-10-Box-Of-35-Roller-Chain-1-1163-35.axd (~$15.00)

& a couple of extra master links (~$0.35 ea.)

& a couple of tie rod ends (~$5.00 ea.)

They have some really good deals, just gotta look & do some price comparing

 

[Functional Artist]

Picked some metal today

Some 2" x 6" x 1/8" (11g.) rectangular tube for the backbone
&
Some 1 1/2" x 3" x 1/8" (11g.) rectangular tube for the front axle

I wanted 1" x 3" rec. tube for the front axle but, they were out of it

Should be able to make it work

I am thinkin' a 6" nose cone & 6" axle stubs, on each side will look kool & balanced

 

[Functional Artist]

Rounded up some 2" round pipe with a 1/8" wall for the rear axle housing
Cut off a crusty end & then a 14" piece
Marked the center & then 3" each way
Put the axle thru with the rims roughly in place

Lined it up with a 2" x 6" just to see how everything looks in "real" life

Looks pretty good to me

Plenty of room
...for the bearing & sprocket on one side of the axle & the bearing & brake on the other
...& to mount the motor on one side of the axle housing & the brake hardware on the other

Gotta weld on a flange or plate to mount the bearings to each side

 

[Functional Artist]

Rear Axle Housing Bearing Mounts

Plan A.)
4" circle, 1/8" flat steel, with ~1 1/2" hole in the middle
welded on each end of the rear axle housing
with some braces added for support

Plan B.)
2" x 2" angle steel ~4", with a ~1 1/2" hole in the middle
would square up on the end of the axle housing nicely
& double as a motor mount or brake mounting bracket

 

[Functional Artist]

Lets lay things out to see where were at
...& start to lock down some dimensions

Backbone - 2" x 6" x 48" long rectangular tube
Front Axle Housing - 1 1/2" x 3" rectangular tube
Rear Axle Housing 2" x 14" round tube

Starting at the front
6" for nose cone
3" for front axle housing
6" for each of the (4) batteries (~24")
which leaves ~17" to the rear axle housing

I think we can squeeze a seat & a motor in there

Not enough room to land a 747
...but, should work

 

[Functional Artist]

Next, where/how to mount the motor
...that should give us more info on how/where we are gonna mount the bearings

Well, lets dry fit
...the axle in the housing
...with the bearings on each side
...& the sprocket
...& the rims

It looks like to line up the motor sprocket with the axle sprocket & to clear the sprocket (have adequate distance between the sprockets)

The motor mount needs to be ~4 1/2" out from the backbone
...& ~6" forward from the axle housing

 

[TT540]

Looks like fun. Thanks for sharing.

 

[ezcome-ezgo]

Rear Axle Housing Bearing Mounts

Plan A.)
4" circle, 1/8" flat steel, with ~1 1/2" hole in the middle
welded on each end of the rear axle housing
with some braces added for support

Plan B.)
2" x 2" angle steel ~4", with a ~1 1/2" hole in the middle
would square up on the end of the axle housing nicely
& double as a motor mount or brake mounting bracket

Plan B is a winner

 

[ian928]

Torsk is Norwegian: https://no.m.wikipedia.org/wiki/Torsk

A predatorial fish but not quite the teeth painted on the boat...

Ian

 

[Functional Artist]

A few more ideas

I made up a couple of "A" frames
...just to see how it would look

NOT feelin' it

Still like the original plan

 

[landuse]

Yup...I'm not too sure about those A frames either

 

[Functional Artist]

Rear Axle Housing Bearing Mounts

Plan A.)
4" circle, 1/8" flat steel, with ~1 1/2" hole in the middle
welded on each end of the rear axle housing
with some braces added for support

Plan B.)
2" x 2" angle steel ~4", with a ~1 1/2" hole in the middle
would square up on the end of the axle housing nicely
& double as a motor mount or brake mounting bracket

Came up with a few more ideas

Plan C.)
4" x ~12" triangle, gusset plates to strengthen the axle housing to backbone connection
& mount the motor or brake on to
(a lot of separate parts to fabricate & weld together & still mostly just (2D) two dimensional)

Plan D.)
2 1/2" x 1/8" x ~24" custom bent steel side plates
with a 5" x 6" motor mount welded on top
(only (2) "simple" parts for each side)


I'm likin' Plan D.
...simple & lightweight
...more (3D) 3 dimensional
...with some triangulation thrown in

 

[Functional Artist]

The rear axle bearing brackets are ~3" x ~4"
I thought about using 3" x 1/8" steel but, the backbone is only 2"

so, I am gonna split the difference & go with 2 1/2" x 1/8" steel

The top & bottom edges will hang over just a bit
but, it should be kool

 

[anickode]

What if you use a tubular rear axle carrier with press fit bearings instead of flanges on the ends?

 

[Functional Artist]

What if you use a tubular rear axle carrier with press fit bearings instead of flanges on the ends?

Doesn't sound very DIY

Always open to new ideas

but, need more info

Pic's, drawings, links ...something

---------- Post added at 08:42 AM ---------- Previous post was at 08:27 AM ----------

I have a pretty good idea on how everything will be layed out
& how the front axle will be set up
& the rear axle too

Next, I want to get the battery "tray" cut out
& then see how rigid the backbone still is

Also, thinkin' about doin (2) 12" x 4" battery cut outs
with a 2" space or bar left in between the front (2) batteries & the rear (2) batteries
...instead of (1) big 24" x 4" cut out

This should help maintain the overall rigidity better
...& the 2" bar should also act as a "frame fuse" or indicator

If the backbone does any extra-ordinary flexing, the 2" bar should show some warpage

 

[anickode]

Do you have access to a lathe?

 

[Functional Artist]

Do you have access to a lathe?

Not currently

I could make some "really" bad azz stuff it only I had access to "more" tools & a proper place to use them in

Gotta work with what I got to work with

 

[Functional Artist]

To cut out the battery box opening
...I could use my cut-off tool but, would have to rig up a cutting guide, (8) times

I think I'll (try to) use a jig-saw for this project
...mostly by eye but, it does have an attachable guide that may be helpful

Starting at the front axle, I drew out where the front (2) batteries will sit. Then, I left a 2" space (frame fuse) & drew out where the (2) rear batteries will sit.

I center punched drilling spots in all (4) corners of where the front batteries will sit & drilled 1/8" pilot holes then 3/16" holes & then finally 5/16" holes to have a place for the jig-saw blade to start from.

The cutting for the first box went really well for the (2) long (12") cuts but, when I cut across from one cut to the other
...@ the very end there was a pop & the metal raised up ~1"

scared the crap out of me

I was just concentratin' & cuttin' along & suddenly the metal came alive