Torsk (Backbone Chassis) Kart

[Functional Artist]

Now that part of the steering is pretty much complete, next is to work on the spindles

When I capped off the ends of the front axle, I angled the plates, where the spindle mounts to ~10*
(I read somewhere, that's how it's supposed to be)
...but, it didn't look right

So, I did some research
(back to the books, so to speak)

http://www.diygokarts.com/vb/showthread.php?t=11760&highlight=caster+camber

So, to set it up right, you have to keep in mind
...Caster (the angle of the spindle, when viewed from the side)
...Camber (the angle of the spindle, when viewed from the front)
...Toe Out (the angle of the spindle, when viewed from the top)
...& King Pin Inclination (an imaginary line thru the spindle main bolt (king pin) to the center of the tires contact patch)

But, it seems that there are no definitive answer
...there are a lot of variables
...& it depends on the specific situation (how the kart is designed & what you intend to do with it)

So, for this kart, I am going to
...set the Caster @~7-8* (10* just seemed like too much)
...redo the Camber, back to 0* (leaning front wheels just don't look right)
...& set it to Toe In just a bit (it's easily adjustable later)

Also, I am using factory made spindles so, there is isn't a lot I can do about the KPI (without extensive work)


Moving on (now, with more info)

I drilled 1/8" "pin/screw" holes in the center if both front axle end plates

Lined the spindle brackets (up/even) with the bottom of the axle tube
...& drilled corresponding "pin/screw" holes

This way I could "screw" them on (evenly on both sides)
...to more accurately place & adjust them

I can lean them "outward" to "fix" the Camber issue (that I caused)

It also allows me to "very accurately & evenly" adjust the Caster on both sides (to matching specs)

 

[Functional Artist]

After double checking the Caster & Camber
...I welded 'em on good

Next, is to make some tie-rods

Used a piece of 1/4" x 1" steel as a straight edge
...layed it across/behind the spindle brackets
...to help align the spindles

Measured, marked & cut a couple of pieces of 5/16" rod
(ya, I know it's kinda small but, it's hard to do light weigh & heavy duty at the same time)
(we'll see how they do, can always add beefier/heavier ones later)

Threaded both ends ~3/4"
...added the center links & ends
...then toed 'em in just a bit

 

[Functional Artist]

I got a little more done on the kart

Back to the seat, kinda

Gotta be able to mount it, before we put the cover on it

So, for the seat bottom, I just drilled (2) holes into the backbone & also, added corresponding T-nuts

For mounting the seat back, I added a couple pieces of 1/8" x 1" "cross bars", with 1/4" mounting holes & added corresponding T-nuts, in the back panel of the seat

I used my "new" spot weld mounting method
...drilled 1/4" holes in the ends of each cross bar
...clamped 'em on & filled in the holes

But, just for Ha ha's I banged the back of the top bar
...just with my hand & (1) side just "poped" off

Well,

"Back to the drawin' board"
...clamped 'er "back in place" & welded 'er on the "old fashioned way"

 

[anickode]

It takes a lot of heat input, real fast, to do a good plug weld.

 

[Functional Artist]

It takes a lot of heat input, real fast, to do a good plug weld.

Important detail

Now, ya tell me

Thanks, now we "all" have more info on the what & why

I'll still use it for just "tackin'" stuff in place
...but, then apply a "good" perimeter weld

Speakin' of
...remember, I just "spot" welded the steering housing foot (as a test)

Abort Test...Abort test
...not waitin' for it to "fail"

So, I went back & added some extra welds to the steering housing "foot"

Had to separate the steering & nylon bushing, again
...welded (1) side
...checked temp
...waited (for it to kool a bit)
...then, welded the other side

Not quite as clean & pretty

but,

Yup, that should do, better

 

[Functional Artist]

Been lookin' into options for front wheels

I would like to use those 13 x 5.00/6 ribbed tires that I have on the front
...but, they need narrower rims (like ~3" wide)

I checked with BMI karts & a few other kart part places
...but, all I found (in 6") was the wider rims (like ~5' wide)

Lookin' in the Surplus Center catalog
...I found some narrower 4.10/3.50-6 rims/tires (hub width 3 1/4") #1-3657 for $12.95 ea.
...But, not sure about them bearings (kinda remind me of HF wheels)

Anyone know of "higher quality" bearings for these type of wheels?

I also found some (kinda outta the ordinary) 6" wheels that caught my eye #1-116259
...they have a 3" wide plastic rim with ceramic bushings
(for use around corrosive materials like salt & fertilizer)
...a 4.00-6 ribbed (wheelbarrow) tire
...& are super light weight

I'll give 'em a try, if they don't work out I can just use 'em on the 2-wheel dolly
(as long as I don't bust 'em during testing)

First pic is of 6" plastic wheel (left), 6" steel wheel (mid) & the 13-5.00/6 tire (right)

Second pic is the 1-3657 steel wheel

Third pic is a close up of the bearing

Fourth pic is of the plastic wheel & bushing

Fifth pic is a side by side of the plastic wheel & the 13-5.00/6 tire

Six & seven are of the kart with the steel rim

Eight, nine & ten are of the kart with the plastic wheel

 

[anickode]

Order floater wheel bearings from a go kart supplier. They're like 4 bucks apiece. Same 1⅝" OD as hand truck bearings. Just press them in and go. That's what I ended up doing on my budget kart with some good quality one piece 6" hand truck wheels. Just a bearing upgrade. When the tires give out, I'll buy some better ones.

 

[Functional Artist]

We have had a lot of rain & humidity lately
...& we're beginnin' to get some corrosion (rust)

I think we have most of the major "frame" stuff done

So, I guess it's time to get 'er cleaned up
...& then, sealed up

 

[Functional Artist]

After several hours of deburring, smoothing, rounding, filing & sanding

When I thought I just about had 'er done, I noticed
...that we got no floorboards or stirrups (so to speak)

This frame is designed for the operator to "prop" their feet right on the front axle housing
...but, for "safety" purposes, I think it would be best to have something down under the feet too
...just in case

 

[Functional Artist]

I got some 8' running boards off of a Ford F250 p/u
...they should do the trick

JK

We don't need nothin that elaborate
...just small plates under each foot

I found a piece of scrap "expanded" steel, that should do
...it's left over from either the Zero kart or the !Arriba! kart (can't remember)

Did some measurin', markin' & cuttin'

 

[Functional Artist]

Once I had the (2) pieces, just had to "dry fit" 'em
...& trim off a bit more of the excess

(1) piece had a nice "finished" edge to it
...but, the other didn't so, I had to do some bodywork

Then, they got permanently attached with a bunch of "blob" welds

 

[ezcome-ezgo]

Cool, looks like a spiderweb.

 

[Functional Artist]

After, lots & lots & lots of clean up (mostly smoothing rough spots)

Using the "WPI" (work piece indicator) concept
...feel, smooth, feel again & smooth some more, 'til it's super smooth

Then, I wiped 'er down with some paint thinner
...but, kept finding more & more rough spots

After a couple more "go overs" I think she's finally ready

While I was at it, I also, cleaned up the steering wheel & spindles

 

[Functional Artist]

Set up a mini paint booth in the back yard

Still, just using' "rattle cans"

Gave 'er a final wipe down & shot 'er

Since, it's mostly bare metal I am using "Self Etching" primer
...it's supposed to "bite" better on clean metal

 

[Functional Artist]

Gave 'er ~1/2 hour to dry then, set 'er down
...& finished sealing 'er up good

Hung the spindles & steering wheel
...& sealed 'em up too

Kinda reminds me of Army colors
...like an olive drab (off-greenishgray)

 

[landuse]

It's coming along nicely. I can't wait to see it all put together.

How long is the kart going to be?

 

[Functional Artist]

It's coming along nicely. I can't wait to see it all put together.

How long is the kart going to be?

Thanks, me too

The Backbone is 48" & the rear axle housing is ~2"
...so, the chassis is ~50" plus the rear wheels

Overall, it'll be under 5'

 

[Functional Artist]

Had some time so, I did some work on the seat

Worked on the seat back first (the easier section)

Cut a piece of plywood to the desired dimensions
...used 1" thick "closed cell" foam rubber & ~1" of "fluff" to soften it up
& round the corners

A friend gave me some faux gator skin type of material
...it seems kinda thin
...but, looks kool so, I'll give 'er a shot

Layed the plywood, foam rubber & the fluff out on the material
...trimmed around leaving ~3" on the sides & bottom for "wrap around"

I left ~ 16" of material @ the top "for wrap around"
...but, also to cover the back side of the plywood (for a cleaner look)

Marked the corners @ a 45* angle
…& sewed 'em up (straight first, then on a bit of an angle so the corners will curve nicely when flipped around the right way)

Stapled 'er all the way around
...then flipped the top "flap" down & stapled 'er down too

 

[gr8hairy1]

Upholstering stuff always makes you feel like a boss of creating things. Seems like more people would do it lol.

 

[Functional Artist]

The seat bottom...
...the battery cut out was a major PITA

I drew it out
...& kinda planned it out
...step by step

But, WOW super complicated to make a cover fit "good"

So, I ended makin' (3) seat covers before it came out "decent"
...not great but, passable
...third times a charm