Ratrod bicycle trailer and soapbox

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Got some work done after aligning yesterday:

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WIDE and FAT

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Clamping/aligning

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Clearance

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Old stuck dirty bearings


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Welded!

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A little camber. Not much.

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Will cut the 'long shafts' from the hubs later.

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Very happy!

Width: centre tire to centre tire is 66 centimetres.
 
It looks good so far, but I think as soon as you hit the first good bump you’re going to develop negative camber in the front.

About -30° Each side, As the front axles bend.

At which time it should stop, because your front axle will be sitting on the ground.
 
It looks good so far, but I think as soon as you hit the first good bump you’re going to develop negative camber in the front.

About -30° Each side, As the front axles bend.

At which time it should stop, because your front axle will be sitting on the ground.
It might.
Due to the fun of trying out, I did not calculate this. Just an approximate guess or feel seeing other carts. This cart will not be used like the 'Redbull' soapbox races and jumps 😉

The 'final assembly' is not done yet and I was planning to place a larger washer or plate there:
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These same hub axles are utilized on my daughters trike too and they get abused! Riding off of curbs... Her spindles are also 4mm but I think forged:
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Another thing to keep in mind is the use and weight. The trike for my daughters is made for max. 40 kilograms. I want this wagon to carry max 60 kilograms.
The (ab)use is as a wagon that you pull while walking and behind a bicycle for road use.

Q: What are the 'radio flyer' or wagons called in the US?
In Dutch it is "Bolderkar" and it looks like this:
berg-bolderkar-extra-large-is-een-stevige-bolderkar-ook-geschikt-voor-professioneel-gebruik-12...jpg


But I appreciate you keeping me sharp and having an hawks eye on the design
 
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Well clearly my imagination was running away from me because I thought this is going to be a motorized go-kart for you.

Around here what you will see in fancy child’s wagons are mostly all built in China now. This is what I bought for my wife to do her gardening.

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More often you see these with wooden slats for sides. This one is going to outlast me and my wife.
 
Well clearly my imagination was running away from me because I thought this is going to be a motorized go-kart for you.

Around here what you will see in fancy child’s wagons are mostly all built in China now. This is what I bought for my wife to do her gardening.

View attachment 252857
More often you see these with wooden slats for sides. This one is going to outlast me and my wife.
No problem Ulu! I enjoy you thinking with me and show your ideas. Something I have a thought or set of values that someone else has no idea about, so there is a discrepancy in perspective 😉

Even tough the approach at my job as mechanical engineer is more professional. I love this way of working too: I don't know where I am going and let the parts/junk I find partially determine my direction :grin:


Very nice!
Reminds me of a Totrod or Cyclekart. People build such cool stuff
 
I am going to share some developing thoughts regarding the steering system.

It is my intention to have a steering wheel in the tub, so we can push it and the kids can steer it. [Then it is a Soapbox]

And have a removable 'pulling arm' just like a [Cart]. The arm should have a radius so it will go around a bicycles rear wheel and it can be attached/coupled to the seat tube. [Like a Bike Trailer].

Implementing these two/three requires a little thought and sketches.

Remember, not the finished design, but some ideas: Feel free to make suggestions since I can change things.

First an example:
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Beautifully made but the small washer and base in the hinge gives me the impression that this will be a bit wonky.

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Thoughts and ideas.

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Some thoughts from the previous picture combined.

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More sketches... don't know about this one....

So I prototyped one idea! Even quicker and cheaper than 3D printing because Danmark. :grin:

Check this out:
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Obviously needs refining, but I can show you the idea!

A movie:

 
More assembly and preparing for another welding session.
I cut off the front part of the chassis and it remains stiffer than I thought.


*generic phone rock song* :21:

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Upside down.

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Little bit of caster. Not much.
I will weld that thick round plate too. It is for the hinge.

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I am thinking to use this is for the hinge. But it is extremely heavy. 80mm IPE beam. 4,5mm thick plates.
Drillium/speedholes necessary 😉
 
I am thinking about painting the rims.
The current yellow with patina looks cool, but I have a weak spot and strong preference for the classic ratrod red look.

What are your thoughts on this?
 
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The chassis base is done. Now lots of small stuff to do before I start with esthetics.

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Stiffening the front ring load (pivot point)

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Thoughts and ideas in regards to the pivot.
The gate hinge part is perfect to attach a wooden beam to pull the wagon.

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Questionmark:
I am contemplating if I am using this HEAVY piece. Since I need to fabricate some bushes and its pretty large too.
I can speedhole it though. Lots of speedholes keeping strength in mind.

I will think about it. Monday I can use the machine shop, so we'll see where this leads.
 
Ah, it is a bit later now, but for good steering at the front you need to choose your camber angle, castor angle and kingpin inclination (KPI). You might find the steering a little heavy without a good bit of KPI as you will be forcing the wheel to move in an arc rather than almost pivoting on the actual tire.
 
Ah, it is a bit later now, but for good steering at the front you need to choose your camber angle, castor angle and kingpin inclination (KPI). You might find the steering a little heavy without a good bit of KPI as you will be forcing the wheel to move in an arc rather than almost pivoting on the actual tire.
I do not disagree with you.
In my defense, I actually copied my daughters (two front wheeled) trike geometry (pictures on the previous page) and I added the ackermann steering and a little more caster.

My daugthers trike steers pretty good, not too heavy. The only aggravating thing is the wheels 'remaining' parallel. So the tires are working against each other, especially in tight turns.

If this thing steers really bad, I will alter it. For now I am a little lazy and utilize a proven design. With a little extra :wink1:

Updates?
Since I am typing this, where is the project right now?
  • I ordered some M5 'left threaded' cutting plates and a tap. For the steering rods.
  • I also ordered some 'tire spoons' second hand to remove and replace the lawn mower tires.
Somewhere next week there will be some more updates.
I am thinking about the tub as wel. It is so rotten that I might find a different tub. I do like the rusty brown on the sidewalls though...

I have a strong preference of painting the rims red. Still thinking about that.
RAL 3001, 3020 or 3028.

RAL 1036 is interesting.

Or keep it yellow and clean the darn rims.

Don't know yet, open to suggestions
 
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Looking at tires now. My inner redneck screams "Go get the tractor tires!!!" But I will think about it for a bit.
There is a guy that sells complete new wheels in the red colour for a similar price of a new tire...
Lots to think about. I'll post it here and decide in a few days.

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Woow! :heart::crazy:!!



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Grass tires. Little knobby.

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Two above: Clean racy tires.




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Complete wheel.
 
Here's a lil something I mocked up 2-3 year ago, don't know if it is any inspiration for you, but you have certainly inspired me, looking forward to your end result 😊
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Wow that looks very cool! Did you build it in the end? Thank you for the inspiration and your kind words! I'm looking forward to the end result too, but I really enjoy these moments:

Parts I made in the lathe!

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The aluminum bushed (top) are for the rear wheels, to secure the distance between the bearings without crushing or put a sideways load on them.

The threaded rods are the steering arms. Delibirately made from M5 (round 5mm) stainless. I'll rather break this part than another from the front axle.

The bottom/left round bush/plate is for the pivoting part in the centre. You can press a M8 allen screw head in there and the round plate part distributes the load from pulling hard on the carts handle and arm.

Can't wait for assembly!

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Time to drill
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This will be the pivoting part of the arm. I intend to fabricate the arm from wood.


Next week the wheels will go to the powdercoater.

I ordered the tires and they will be wide semi slicks.
I can paint 'Hoosier' on the sidewalls.....
If you guys have any advice on tire letter paint or methods, I'm all ears!
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Wow that looks very cool! Did you build it in the end? Thank you for the inspiration and your kind words! I'm looking forward to the end result too, but I really enjoy these moments:

Parts I made in the lathe!

View attachment 254173
The aluminum bushed (top) are for the rear wheels, to secure the distance between the bearings without crushing or put a sideways load on them.

The threaded rods are the steering arms. Delibirately made from M5 (round 5mm) stainless. I'll rather break this part than another from the front axle.

The bottom/left round bush/plate is for the pivoting part in the centre. You can press a M8 allen screw head in there and the round plate part distributes the load from pulling hard on the carts handle and arm.

Can't wait for assembly!

View attachment 254175
Time to drill
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View attachment 254177
This will be the pivoting part of the arm. I intend to fabricate the arm from wood.


Next week the wheels will go to the powdercoater.

I ordered the tires and they will be wide semi slicks.
I can paint 'Hoosier' on the sidewalls.....
If you guys have any advice on tire letter paint or methods, I'm all ears!
View attachment 254174

I do believe @The Renaissance Man has the low down on tire lettering
 

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