Damien

[Functional Artist]

I got some new ideas.

I'ma gonna call this one Damien.

Just cause it sounds kool & I can give another shout out to a local (Toledo) '80's Metal band, Damien.

Check out, their one hit (it got played on MTV many times) Every Dog has it's Day
https://www.youtube.com/watch?v=YdtZpFK1Xig

I'ma thinkin' a super light, 3D style frame with rear suspension. (maybe)

So, startin' off @ the drawin' board. (notebook, actually)

We'll have (2) lower frame rails, a left & a right. They will curve up in front & lean outward toward the tires, as they come back as top rails on each side, then wrapping around & meeting in the rear, kinda like a "spoiler".

 

[landuse]

Looks interesting. I think I might have a clearer understanding when you actually start the fab work

 

[Functional Artist]

Maybe, another perspective will help

 

[landuse]

That helps

 

[ezcome-ezgo]

Let me try something..

 

[Tpdingo]

All I can think of frim the side profile is making the rear part of the cage at a steeper angle and sticking some big drag slicks on the back and some pipe right out the top like a truck.

---------- Post added at 10:57 AM ---------- Previous post was at 10:52 AM ----------

All I can think of frim the side profile is making the rear part of the cage at a steeper angle and sticking some big drag slicks on the back and some pipe right out the top like a truck.

 

[Functional Artist]

Let me try something..

Wow! That is soo kool.

---------- Post added at 10:52 AM ---------- Previous post was at 10:48 AM ----------

All I can think of frim the side profile is making the rear part of the cage at a steeper angle and sticking some big drag slicks on the back and some pipe right out the top like a truck.

Ha, Ha
...totally different

 

[anickode]

Wow! That is soo kool.

---------- Post added at 10:52 AM ---------- Previous post was at 10:48 AM ----------



Ha, Ha
...totally different

Somehow I get the feeling FA isn't going to need the big smokestack exhaust...

 

[Functional Artist]

Side rails

I haven't started the fab work yet, but the plan is to start off with a 10' piece of 1/2" schedule 40 water pipe. (Home Depot ~$10.00)

First, we will bend it, right in the middle, to the max, with the bender.
(kinda like the rollbar/seat backs that I use on most of my karts)
So, then we will have a top rail & a bottom rail that are a little bit under 5' (60") each. (see fig. 1)

Next, we need to put a ~60* upward bend into the bottom rail ~10" from the rear of the pipe.
So, then the bottom rail will then be ~50" from the front bend to the rear bend & have a ~10" kick-up
(see fig. #2)

It looks like the top rail will still be angled a bit too high to intersect with the kick-up of the bottom rail.

So, then, we will probably need to put an ~20* bend in the top rail to bring it down a bit to intersect.
(see fig. 3)

They don't really intersect, but need to end up "close".

I played around with & bent up a piece of wire to help illustrate the concept.

 

[Tpdingo]

I really like that swooping front. Gives it..I don't know how to describe it...Ariel Atom look? Its like a combination of having an enclosed design but also open. Whatever it is, I approve .

With it having side rails, how is the structure going to be? Basic ladder, Unibody, another backbone kart? I think if you would nail down the body structure of the atom, but a bit more open, but still keep it very rigid, we would have a VERY nice combination on your hands.

PS:
*whispers* Come over here
*shouts(in your ear)* NEED BIGGER SLICKS!!!

 

[Functional Artist]

I really like that swooping front. Gives it..I don't know how to describe it...Ariel Atom look? Its like a combination of having an enclosed design but also open. Whatever it is, I approve .

With it having side rails, how is the structure going to be? Basic ladder, Unibody, another backbone kart? I think if you would nail down the body structure of the atom, but a bit more open, but still keep it very rigid, we would have a VERY nice combination on your hands.

PS:
*whispers* Come over here
*shouts(in your ear)* NEED BIGGER SLICKS!!!

Yup, I can see the resemblance.
Ariel Atom's are Bad Azz! Imagine an electric powered one
...maybe a future project

I think the Damien kart is gonna be more of a 3 dimensional "space frame" style, kinda like the Atom, but (as you say) more of an open design. It's definitely gonna have some of the same structural characteristics, but should be quite different.

I think the frame should look kinda/almost sleigh like (shudder) during construction, but (hopefully) look a bit more Indy car like with the wheels on.

First pic is of an Ariel Atom frame, & then are some pics (playin with more wire) to help illustrate the (sleigh) concept better.

 

[Functional Artist]

Dimensions

The bottom rails should end up being ~4' (~48" of straight rail) from the rear bend to the front bend.
(the bend takes up a little bit of length)

So, if we mount the rear axle right near the rear bend & the front axle, 'Oh, lets say ~8" from the front bend, then we should have a wheelbase of ~40".

Yup, I think that should work.


What about the width of the frame?

Well, the rear axle that I am gonna use is 36" so, I guess we'll start there.

I am kinda thinkin' (maybe) balance the battery pack right over top of the rear axle.
(kinda like when you tilt up a loaded wheelbarrow to "balance" the load & it seems to motivate easier)

With these goals in mind I designed a trailing arm (swing arm) that incorporates a battery box, axle mounts & motor together in one compact package.

I simply lined (4) 12V 15AH SLA batteries up in a row (~4"D x ~16"W)

I first thought, we'll use 1 1/2" square tube on each side of the batteries & ~1 1/2" angle steel across the front & the rear of the batteries. The pieces of angle steel would connect with the side tubes forming a box around the batteries while also providing a very strong front & rear shelf to support the batteries.

After thinkin' about it a bit it seemed like that particular design may be prone to flexing, even with the rear bumper helping to stiffen things up.

Then I thought, why not just use the square tube all of the way around?

Yup, that idea seems stronger (less prone to flexing) so, I gave it a try.

I cut (2) ~16" pieces, (2) ~14" pieces & a 30" piece of 1 1/2" steel tube. When I layed them out around the batteries it just looked over built "too beefy" & was really wide. (~19 ") Plus, just those (5) pieces of tube weighed ~17 lbs.

I like the concept, but need to go smaller & lighter.

 

[Tpdingo]

With those wire models, I think you should make the middle of the kart relatively boxy, with a few small radius bends but in the front give the kart that nice 160 degree turn. Make it a good radius.

I wanted you to do the 3D space frame design.

 

[Functional Artist]

I made-up a swing arm out of 1" square tub. It looks a lot more proportional to the batteries. It also weighs a couple of pounds less too.

The 6" of tube extending in front of the batteries on the left is where the brake caliper will mount & then the motor will mount on the right side.

The motor mount is a 3/16" x 4" x 6" piece of steel. I doubled up the 1" tube under the motor to give it more clearance & also added a small perpendicular piece underneath for extra strength.

The pillow block bearings & axle simply mount to the bottom of the swing arm, centered right up under the batteries.

Yup, I think that will do

 

[Tpdingo]

No differential? I want my money back

Haha, just kidding. I like it. So its going to have suspension? And particular reason to mount the batteries to the swing arm or just because there is room there?

 

[Functional Artist]

And particular reason to mount the batteries to the swing arm or just because there is room there?

Did I ever tell ya the story about the man who took all of his clothes off & sat on a cactus?

He said, "it seemed like a good idea...at the time"

JK, it just seems to be a nice little package.
When its set it up like this, the weight of the bat pack will be "unsprung" weight.
Not sure if that's good or bad, we'll see how it goes.

 

[Functional Artist]

Hinges

Next, we gotta figure out how to connect the swing arm to the frame rails. (hinges)

The easiest method would be to just run bolts thru the side of the frame rails into & thru (the sides of) the front edge of the swing arm rails.

But, its usually not a good idea to drill holes or put bolts thru the frame rails themselves. (weakens it) So, I'll add/weld a short piece of square tube to each frame rail & run the bolts thru them.
(It'll also help spread out the pressure, being applied from the pivot point onto the frame rails)

I overlapped the (2) square tubes a bit, slid in a couple of rub/wear pads & added a "cross bar" to aid in alignment. (not sure yet if it's gonna stay)

Yup, that should do it

 

[ezcome-ezgo]

I enjoy your attention to detail.

 

[Functional Artist]

Flipin' the script

Lets get back to makin' the frame rails.

Thinkin' it thru. I think were gonna change the plan a bit.

Anymore, I try to "pick my battles".
It seems that tryin' (mostly by eye) to do (5) bends on several different planes & angles just doesn't look like a battle I can win. Even if, (boom!) I did it, what are the odds of doing it again, but (exactly) backwards this time.
So, plan B is to "split the baby". (no actual babies will be harmed in this process)

I will cut the rails (pipes) in 1/2. Then the top rail will only have (2) bends, the bottom rail will have (3). This way I can incorporate the mounting of the front axle & then, also use it to help in aligning the frame rails.

 

[Functional Artist]

We'll make the bottom rails (the base/foundation) first.

First, we gotta mark where the bends go.

We have (2) pieces of pipe ~60" long, so we'll mark both of them (rear bend) @ 12", (pivot) @ 18", (second bend) @ 6', (third bend) @ another 6" & then there should be ~18" left.

The first bend (@12" mark) took 50 pumps to get'er close to the 60* were looking for. (I did the same bend in both pieces)

Then, lined up the first 6" mark (30" from the beginning) & turned the rear bend up until it was horizontal. It took 12 pumps to bend/swing it over (close) to where it needed to be.

Next, I slid up to the second 6" mark & flipped the pipe 180* to do the next bend. It also took 12 pumps.

I did the other frame rail the exact same, but opposite.