Billy Cart #2

[mick59wests]

I have just started my second billy cart. Usually I don't publish anything until I am nearly finished as each project takes so long. Working gets in the way of so much!

Anyway, I started on my next billy cart and although it is slow going I am happy with the progress. I did get help from this forum for both the brakes and scroll sawing the steering wheel - both from the LiliB/Dave team.

I can't say it is up there with the quality of Dave and Lili or Aussie or Chipman or .....but I am very pleased with current progress.

The steering wheel is as intricate a piece as I have made to date. It is not perfectly cut but took me more than an hour just to draw it on paper!

To give an idea of scale (which I should have thought of when doing the photos) the base is 650x200, so this is probably for a 3 to 7 year old. As yet I do not have any grand-children and hope I am not tempting fate with my 21 and 19 year old children but I have got the bug!!!

It is all western red cedar except for the brake pedal which is silky oak. I plan to make the entire car from cedar.

For me, any comments/suggestions, etc are always most welcome.

cheers

Mick

[Garell]

Its coming along well. I like the steering wheel.

Never fear all good things take time to build.

Regards Jamie

[LiliB]

Hi Mick

I am pleased to see that you have some more ideas on how to manufacture components on your billy cart. The steering wheel looks good.

When I can tie down Dave to a moment of inactivity in the shed, I'll get him to show you some ideas on steering. Apparently the steering is quite technical but he has solved many of the problems associated with making it hard to turn. It's apparently something to do with caster and camber on the wheels.

Anyhow, he assures me that steering can be solved, and that there are choices other than the old rope trick.

If there are specific things you might like to discuss with Dave, PM me and I'll attend to it.

Cheers
LiliB

[wheelinround]

I was going to say your a bit old for Billy carts :p looking good.

What ever happened to kids building their own scrounging parts needed off old prams and push bikes scooters etc same with the wood from piles on foot paths.

Kids need designer Bill carts these days :roll:

At a meeting the other day someone said they had priced all the bits needed to build a cart total $350:doh:

[mick59wests]

I did say I was slow in making whatever my current project is. Anyway I have completed the brake (thanks again to LiliB/Dave) and seat (which helps hold the brake). Lucky I have no end date.

I can't say how well the brake will work with weight and momentum behind it (or whether the driver will be able to do donuts) but it certainly stops the wheel.

cheers

Mick

[AUSSIE]

Mick.What are those wheels made from?
If plastic ,the centre may break out under braking load.
Aussie

[LiliB]

Hi Ross and Mick

When Dave and I discussed steering and brakes, Dave pointed out to me that certainly with steering, there are considerably less complications with a self propelled vehicle than one with mechanical assistance like a motor. For one thing, castor and camber don't come into the equation, because the wheels don't go fast enough to roll over in corners. I would say that even the wheels, in a situation like this, won't have the sort of stresses on them, that one might expect.

Going on the fact that modern pedal cars seem to be made almost exclusively from plastic, I would say the plastic wheels should do the job. Obviously, it would be ideal to have steel wheels, but even steel wheels today, probably won't be of the quality of the old cyclops pedal cars.

What impresses me, though, with the whole project, is that Mick is coming up with a real 'niche' product, that should appeal to parents who have a sentimental attachment to their childhoold toys, but like to go one step further with what they buy their kids.
The finished products should be real collectibles, and I wish Mick the best of luck with his cars.

They are certainly going to be more than billy carts. Perhaps, in time, he might like to get them on the road at the Billy Cart Championships held somewhere in Western Victoria (Can't remember the name of the little town). Would probably blow a few minds there, and publicise the product.

Cheers
LiliB
:U:U:U

[AUSSIE]

Sorry,but we have all seen a billycart derby where the cart gets the speed wobbles,and the driver can't control it.So, over it goes.I have gone from billycarts to radio controlled cars etc.over the years Straight line control needs castor plus you need to go around corners sometimes.Billy carts may get a harder time than kids plastic pedal cars.As you said in billy cart derbys etc.
Anyway, the thing about the brakes was,you have a thin axle and a wooden drum on it for a brake drum.with a leather belt around it for the band.
Then a wheel attached to the axle.
It looks like to me , when you put pressure on the belt to stop the billy cart,that is going faster than a pedel car with a much older kid than what be in a peddle car (heavier) something is going to brake or bend.
The belt is trying to pull the axle forward
the axle is thin
The wooden drum could break along the grain
The axle/drum could seperate from the axle
and other problems.
These carts get up a fair bit of speed down hills and we are talking thrill seekers with no fear.(6 yo up say)

[LiliB]

Hi Ross

I actually think the whole idea of building such a car is fraught with danger. My first reaction was 'my God, what if the kid falls out and breaks his neck. The public liability of the incident could be horrendous'. That's basically why I asked Dave whether he could think of safer ways to steer and brake, than a wooden block on the wheels and a piece of rope to steer.

If I went into such production, I would probably want to test the mechanicals on a rolling chassis before I went ahead and built it. I would also want my mechanicals to be made of steel, with the timber just like coachbuilding of the past. I think you have to cover yourself for any luny that wants to sue you for an unroadworthy vehicle, so I wouldn't go there anyhow. I've got too vivid an imagination and can readily think of too many scary scenarios.

Certainly, you'd have to do testing with the wheels on a steep grade and see how much camber was needed in the extreme speed situation. I'd probably want to talk to a mechanical engineer to ensure my parts were heavy enough in construction to stand up to the potential uses of the vehicle.

But then, I'm a worry wort, which is why I'm not in business!!!

Cheers
LiliB
:U:U:U

[bpj1968]

Steering geometry is a whoel world in itself.

I read an article a while ago relating to castor effect on bicycles relating to head angle, rake etc. Basically it was a small kids bike NOT designed for any real speed. Little girl gets on and goes down a steep hilll at big speed, and gets the wobbles, can't control it with fatal results. I'm pretty sure the reason was as follows. In effect drawing a straight line down through the head stem to the ground showed that the tyre met the ground at the same point, although the axle is in front of that imaginary lline. This makes it very responsive, but unstable. The further back the tyre contacts the road the more stable, and more of a castor effect.

On cars camber is designed to assist steering. When turning the steering wheel it is ideal that the tyre rotate near the centre. Which is why upper and lower mounts are differnet. Tow-in is mainly to overcome the drag of the tyres, castor to help the car want to travel striaght.

As had been mentioned at pedal car speed not a big issue but at billy cart speed control is important. easy to reach 30+ speeds without much of a hill.

[mick59wests]

Aussie, LiliB and Brian,

thanks very much for the comments and constructive criticism.

Aussie - I appreciate all help and see where you are coming from. I think this car is more likely for a 3 to 5 year old and hope no one goes too hard in it! Your comments also show I have a lot to learn. I have always been a hopeless mechanic and am not really sure why these cars have taken my fancy but I am planning to learn.

LiliB - with comments like yours, you have a friend for life!

Brian - I think it will take me a year of study to even understand what you have written! This just shows how little I know about making a vehicle that is designed to 'go fast'!

Thanks again to you all. I'll be trying to learn as much as I can with each car I build from both a mechanical view and good woodworking.

thanks

Mick:):):)

[AUSSIE]

Keep it going Mick.:2tsup:We are just trying to help.
I think we got a bit out of hand really:2tsup::2tsup:
Have a look here (http://users.bigpond.net.au/mechtoys/billycart.html)&here (http://www.bladeschool.com.au/billycart.html)&here (http://www.bunnings.com.au/files/File/diy/How%20to%20build%20a%20billy%20cart2006920125354609.pdf)&here (http://www.dedwards.id.au/David/Billycarts/Billycarts.html) & Here (http://billycart.com.au/)

AUSSIE
http://www.billycartgallery.com/index.php?cartType=11
http://www.billycartgallery.com/assets/dispImg.php?img_ID=239&mode=full

[AUSSIE]

Hey Mick,How is the Billycart going:2tsup:

[mick59wests]

Aussie,

I did say I was slow. I have been cutting out and staining the sides for the seat. Maybe by the end of the weekend I will have completed the seat. I am still thinking about what steering mechanism I will be using. Hopefully some more pics soon.

thanks for the interest

Mick:)

[mick59wests]

to those holding their breath to see my next advancement I am sorry as you would all be dead by now.

I have completed the seat (well almost - I still have to screw in). I am planning on a boot and then have to tackle the steering.

[AUSSIE]

Looking good Mick.:2tsup:
Is it comfy?
Aussie

[AUSSIE]

Looking good Mick.:2tsup:
Is it comfy?
Aussie
Mick I just found this HERE (http://www.vintageprojects.com/tractors/baby-wooden-tractor.html)

Wooden Fame Tractor Plans (http://www.vintageprojects.com/tractors/Baby%20Tractor%2015090.pdf)

[mick59wests]

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:)

[munruben]

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.

[mick59wests]

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

[AUSSIE]

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

[mick59wests]

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 :D

Mick

[mickelmaster]

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.

[mick59wests]

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

[AUSSIE]

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

[MICKYG]

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

[mick59wests]

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

[Skew ChiDAMN!!]

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. :wink:

[mick59wests]

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

[Skew ChiDAMN!!]

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


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! :yes:

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!? :D)

[Skew ChiDAMN!!]

OK, here's what I think is the easiest way to improve what's there, using what you've already done.

Replace the top board (that the steering column goes through) with a full-width, longer one that extends over the top of the front linkage.

Bolt it in place, as it'll be taking a LOT of load... The longer the overlap of the two boards, the stronger it'll be. I reckon a coach-bolt or similar with washers at each green X should be about right. I'd put the heads underneath, with the nuts on top to improve ground clearance and stop the threads from burring over from the inevitable impacts with gutters, etc. :wink:

Use U-bolts or similar at the red X's, to convert the linkage into the fixed cross-member... packers can be used between the board and the cross-member if you want extra ground clearance.

Of course, this means that what's currently your fixed cross-member will now need to become the linkage and must be able to move freely, so you'd need to cut the existing slot wider in front of and slightly behind the axle, and maybe a mm or two deeper. (the pinkish bits in the picture.)

Once assembled, pack this channel with grease... it'll need it!

Finally, I'd cut off the part of the steering column that sticks out the bottom (again, to improve ground clearance) and move the string to roughly where the yellow lines are. It may take a bit of rethinking about where you run the string - and perhaps a roller or two - but that's only a minor detail.

Voila! A trailing axle, with the stub axles in the right positions and it should take the weight of even a fairly beefy kid. :)

[mick59wests]

Skew,

many, many thanks. As they say, a picture paints a thousand words and I even understood your crow-bar simile. I can see how your design will make it much stronger. I am just going through a second childhood doing things I missed out on the first time through!

Don't look back too soon as I have just promised my daughter to build a worm farm and I have started on a coffee table. Wose than that I have to go back to full time work next week!

Thanks again :2tsup::2tsup::2tsup:

Mick

PS: What software did you use for your drawing over the photo?

[Skew ChiDAMN!!]

Glad to have helped.

I reckon it makes life easier when you understand the "why" of things, rather than just being told "this is better." :wink:


PS: What software did you use for your drawing over the photo?

RGS-AvancePaint, a free download (2MB) from http://users.belgacom.net/rgs/avancepaint.htm.

I've only just installed it myself, so haven't put it through it's paces, but it seems to be a well thought out package. Now I just have to learn how to use it properly... :rolleyes:

[mick59wests]

It has been a while since I took Skews advice and adjusted the steering on my billy-cart. As a picture says a thousand words, below is the new and improved model. I still have to find someone to do a test drive to see how long it lasts before I have to get into the repair cycle!

Mick

[AUSSIE]

Looking a lot better now Mick, Is it easy to turn the wheel?:2tsup:

[mick59wests]

Aussie,

I thought you might be the next person on the post!

Whels are good to turn (although a longer axle would have allowed wheels to turn more) but I have not had someone riding and turning at the same time. Once I find a volunteer I will let you know how it rides. If nothing else, it has been an interesting learning experience.

cheers

Mick

[AUSSIE]

Aussie,

I thought you might be the next person on the post!

Whels are good to turn (although a longer axle would have allowed wheels to turn more) but I have not had someone riding and turning at the same time. Once I find a volunteer I will let you know how it rides. If nothing else, it has been an interesting learning experience.

cheers

Mick
Hi Mick.Can you put up a full front view from down low please.?
You weren't asking me to be a test dummy were you?:D:D
I won't do it-- only because I am over 6ft tall and won't fit.:B:C