My Design

[Simon Thomas]

Cut the 2nd used old sprocket for attching the disc brake. Cut the hole out to fit the bigger diameter of brake disc holes.

 

[Simon Thomas]

Brake disc is attached.

 

[Simon Thomas]

I modified the 2 wheel hubs and made the strectching cut with grinder. This will hold the hub onto the axle rod later. Will explain this set-up detail in next round.

Should continue the works next weekend.

 

[Simon Thomas]

I continued my work today.

Need to complete the repair of my 1st design buddy. To avoid forgetting the repairs that I need to do, I earlier on printed out the pictures of the problem. This way really helps.

My car porch is always my mini workshop before bringing the part and fix on the buggy frame.

 

[Simon Thomas]

Firstly, I cut the screw with my grinder.

 

[Simon Thomas]

Marked the centre of the axle rod ends.

 

[Simon Thomas]

Then I welded a threaded rod on the axle rod ends.

 

[Simon Thomas]

I finally included the wheel hubs on both axle rod ends.

 

[TeamCheap]

Impressive

 

[Simon Thomas]

Then I travelled to my friend's house where I parked my buggy. My buggy has been left here for quite sometimes therefore it looks dusty.

 

[Simon Thomas]

I aligned the axle rod, brake disc and chain sprocket before welding the bearings screws.

 

[Simon Thomas]

This is the 4th time so far I could remember I have repaired my broken rear axle rod. It is all started with the threaded rod some time ago. This time, I am using about 4X stronger than the first one.

 

[Simon Thomas]

Finally, it had been fixed successfully. I drove my buggy as a test drive on the road and I did not find any problem with it. This new axle rod uses a bigger sprocket size compared with the earlier one. This bigger sprocket helps pushing my heavy buggy frame plus a bigger axle rod much better.

 

[Simon Thomas]

Impressive

Thanks for the motivational word TeamCheap.

As mentioned in my thread, this is the 4th time I could remember fixing the broken axle rod. Changing from a small 1" diameter to 2" diameter rod.

I have gone through failure by failure here. But in the same time, I also learned so called my own "recipe" in dealing with problems I encountered here.

 

[landuse]

Well done. I am glad you have got your buggy going again. As you say, with the bigger sprocket you will have more torque, and will be able to pull yourself around much easier than before.

Now you have to move on to your second buggy again and finish that

 

[Simon Thomas]

Hi Landuse,

Thanks.

I am still considering to complete my 2nd buggy design with the current set-up. I failed with my 6.5HP engine with the centrifugal clutch. Unless if I change the engine to motorbike engine, may be that will help. This is what I learned from the 1st design. However, I haven't found the engine yet. If I am lucky, I may get the second hand motorbike engine 100cc around RM500 here (roughly around USD170).

Then the 6.5HP engine from the failed 2nd design, I still have the use for my pump ski boat which I am now planning to proceed as well while waiting for luck to have the second hand motorbike engine.

I like the word used by Toystory4WD "Theory and practice are two very different things". This is very true! Same to another version we always hear like "Practice makes perfect".

Hope you are doing well with your current project Landuse. I still browse around and follow-up on some of the threads from active posters here which I believe they are also very much like me like DIY works and using simple / practical approach with their design using their decent tools. That's why I come accross one brilliant ideas in resolving my disc brake hub. I borrowed the idea from this website.

 

[landuse]

Thanks

You say that the centrifugal clutch failed. Why don't you just try change the gearing a bit, and see if it works then. If I remember correctly, your gearing was too high. You might still get it to work without getting another engine

 

[Simon Thomas]

I was thinking to include a set of small and big sprocket between the engine and wheel sprocket, but the problem is the space constraint. Well, a good suggestion from you.

 

[Simon Thomas]

Something like this as in my sketch. Do you know how much teeth of small and big sprocket I need in the middle? I have no experience in this. If I am not wrong, my engine sprocket has 14T, and wheel sprocket has 47T.

 

[landuse]

OK...what you are talking about is a jackshaft (JS). It doesn't have to be too big either. I have included a picture of the one that I used on my bike.

You would probably want a gear ratio of about 8:1. You now have a ratio of 3.35:1, which is too high for you.

To use a jackshaft, the gearing calculation is a little different. It is (clutch sprocket/JS in) * (JS out/rear sprocket). You divide the bigger number of teeth by the smaller.

If you want a jackshaft to give you a ratio of 8:1, you setup would look like this:

(14(clutch)/?) * (?/47) = 8

You could use a combination like this to get your answer:

(28/14) * (47/12) = 7.88

You could even use a slightly larger sprocket than the 28 for your 'JS in'. This will then give you a ratio of over 8

You will have to see what size sprockets you have available to you, and then do the calculations until you find a combination that works for you.

I hope this helps