Thread: Billy Cart #2

Originally Posted by AUSSIE

Looking good Mick.
Is it comfy?
Aussie

Mick I just found this HERE

Wooden Fame Tractor Plans

Aussie,

thanks for that plan. Lots of good ideas in there.

I have to find someone young enough to try the seat. this one is a bit small for me!

cheers

Mick

Looking good. Was there a reason the seat is made of slats instead of a solid piece of timber. Looks like it could be a bit uncomfortable to sit on or are you going to pad it somehow or have a cushion? Great project, very interesting.

I actually got the idea those slat seats from the design of another billy-cart. I think they look good. I put them on my 'big billy-cart' but used a cushion when I test drove it. I think it would be far more comfortable with a cushion but I will wait and see when it gets some test drives in. I will then think of whether I can make a permanent cushion seat. I have a small amount of leather that I could use and some foam.

cheers

Mick

Nearly 2 weeks since update Mick
Not that we are pushing you though.We just want it out of your kitchen

Well, I did say I was slow. This time afew other things slowed me down but I am making siome progress once again. If I was paid for my time, I would have the world's most expensive toys!

I am still having some technical problems with my steering apparatus - I removed the wheels and now have not been able to get one back on without it falling off. Anyway, I have called in the first of my helpers for that problem. In the meantime, I put on a boot. I had a first go at making hand cut dovetails and the low quality of the pictures makes them look good!!!! Actually, they are not too bad but still a bit rough. Lucky for me, this is all about learning.

Hopefully my next update won't take so long

Mick

If you do happen to have trouble with the brakes, eg. they damadge the wheel or dont work 100% you could make a very simple brake that goes straight onto the wheel, so you push it down and it touches the top of the wheel, or wheels if you have 2 brakes, i used to have a billy kart that went like that.

I have completed the steering. It may seem a long time ago I started this, but I have not been doing paid work for about 3 weeks so (for me) I am going quite quickly! If based on an hourly rate this billy cart (for its size) could be the most expensive one in the world. Anyway, I had lots of 'fun and games' getting a 40 degree angle into wood. It is now ready for someone (who I have to find) to do a test run. The steering wheel does turn the wheels but I am thinking I may need a larger one to make the turning easier. Anyway, I will wait for a test run.
Enough of the dribble, here are the latest pictures.

cheers

Mick

PS: As always, I am always after suggestions/criticism/chat

- some witty saying which I have yet to think of

Hi Mick
I cant work out how the steering actually works mate.
Can we have another photo with the wheels it the turned position please.
Also having trouble with the frame setup for the frot wheels.How does it hold the cart off the ground when you sit in it?
I will have another look in the morning ,after a sleep it is now after 1.00 AM

Mick, Like the other contributor i am unable to work out how your steering will work. I would like to offer some ideas from my Billycart days of long ago. The steering consisted of a board which protruded out the front 300 / 400 mm, about 100mm x 30, and attached to that was a single board across the board just mentioned with a single bolt in the centre. The front axle was attached to this board and steering was accomplished by your feet one on either side and was aided by a rope like the reins on a horse. They never had any brakes.

The centre of gravity looks a little high with the use of the slats across the top where you sit. Perhaps you need to have a serious look at the steering in your pictures particulary the safety issue. Every kid had a billycart in the 50's and 60's and I dont remember any bad accidents with them despite going down a steep sealed hill where we used to have our derby to the disgust of the people who lived on this street in Balmain, top job Mick but may need a little more work.

Regards Mike

Aussie,

I will do my best to explain.

The steering wheel is firmly attached to the steering shaft. At the bottom of the steering shaft, the rope is tied around and attached to the 'steering mechanism'. The home made steering mechanism has one of the large axles screwed into the frame. This can NOT move. The ends of the rope are attached tigthly near the front two pivot points (each corner of the axle can pivot). As the steering wheel turns it pulls on the pivot point thus turning the wheel.

It is really just the wheels which are holding it above the ground The one axle which is screwed into the frame also stops everything from dropping

Unlike my first billy-cart I wanted to use a steering wheel for this one (I needed to learn at least something new). This cart is quite small and probably only suitable for someone up to 4 years of age. I was worried about the centre of gravity, but the whole frame is only 30mm off the ground so I hope this will help.

Hopefully this helps but I am happy for questions and other suggestions.

cheers

Mick

A couple of suggestions...

At the moment the steering is a "leading axle" and if either wheel hits a stone, etc., the steering will want to pull drastically to that side. Ideally you want it to be a trailing axle, so that in the same situation it'd act to straighten the steering.

(Think of it as the difference between pushing a stick along the ground and dragging the stick. The dragged one doesn't "bounce your hand around" as much.

Or shopping trolleys. No, no... on second thoughts, lets not go there... [shudder])

Also, the positioning of the stub axle (ie. wheel centres) isn't quite right. The stub axle should be closer to the fixed member, with greater distance to the floating member, so that you get better leverage of the steering. At the moment you have it backwards; set up for a trailing axle, not a leading one.

It should be a simple enough mod to change both things in one fell swoop: re-arrange the mounting of the front end so that the body/board bolts to the front-most cross-member, not the rear one.

Skew,

thanks for the comments. I am always looking for ways to improve and as you can see with my current knowledge there are many!

I wish I knew about the 'leading axle' part before hand. My investigations obviously were not thorough enough! I can't say this would be easy to change but I will think of how I can do this.

I did not understand your 'stub axle' comment. One of my mates who I got some help from said that the greater the distance between the two 'long' axles, the easier the steering would be. The steering would be 'slow' but easier. I also understand that a bigger steering wheel would make it easier to turn and depending on a test drive I could build a bigger one.

The fact I easily understood your first comment was good for me . If you could have another go at explaining the stub axle part I would very much appreciate it.

cheers

Mick

(Can you guess who wasted their youth building hot-rods? )

Originally Posted by mick59wests

The fact I easily understood your first comment was good for me . If you could have another go at explaining the stub axle part I would very much appreciate it.

It's all a matter of leverage.

Think of the stub axles (the 'T' shaped pieces at each end with the wheels hanging off 'em) as small crowbars. The wheel is the "load," the pivot on the fixed cross-member is the business end of the crowbar and the floating cross-member is your hand.

As it is, the wheel (load) is up near your hand. This makes it harder to move than if the wheel was closer to the pivot. Some of your effort is going into physically moving the wheel sideways an inch or two and that's wasted effort... all you want to do is angle 'em.

If you swap the two stub axles over, so that the wheels are mounted closer to the fixed cross-member, then it'll make the steering much easier. Possibly even reducing the amount of effort needed at the steering wheel by half!

You may need to trim back the front corners of the body's board to allow for wheel clearance, but that doesn't look like it'd be a problem.

(This won't change your steering ratio, though... ie. how many turns of the steering wheel to get from full lock one way to the other. To change that, you'll need to change the diameter of the bottom of the steering column where the string wraps around... making it larger would reduce the number of turns needed.)


There's also the matter that all the weight of the front half of the cart is being taken by the pivots on the fixed cross-member. The stub axles are acting like crowbars, remember? Not just sideways, which you want, but also up & down too. So the closer the wheels are to the cross-member, the less leverage they're applying and the less likely the pivots will break when someone sits in it.

Ideally, you want both the board sitting on both the cross-members, with some sort of arrangement to allow the floating cross-member to slide easily underneath while still sharing the load from the board. (A heap of grease!? )