My Design

[Simon Thomas]

New Improvished Rear Axle Plan

My new improvished rear axle setup should look similar to this.

 

[BriggsTwins]

ok, i like the way you have chosen to set this up. what have you decided on with the axle and mounting the sprocket/brake disc? what is your axle length?

 

[Simon Thomas]

Axle Length

ok, i like the way you have chosen to set this up. what have you decided on with the axle and mounting the sprocket/brake disc? what is your axle length?

Hi BriggsTwins,


1. Tomorrow I will install and mount them back.

2. Roughly the axle length is about 135cm. However, I believe still need to cut the tip a bit later to fit the length with the front wheel so that they both have the same length.

Hope I answer you.

 

[BriggsTwins]

yea no problem! thats a good length and the only thing else i wondered was if you found a way to mount the sprocket and brake disc

 

[Simon Thomas]

yea no problem! thats a good length and the only thing else i wondered was if you found a way to mount the sprocket and brake disc

Agree on the improvement of mounting the sprocket and brake disc. One thing I will do in future is cutting a thicker metal sheet to replace the washers or ask machinist to do it for me. Although I never had bad experience with the washer hub being loose of broken, but it is still not realiable. What I do now with this modified welded hub (actually welded washers), is welding it thicker in hope it will not break. Only time will tell this is reliable or not.

I admit, I still need improvement here and there beside this part. This design is merely an experimental design and as a stepping stone for my next proper and better design (subject to if I still have chance and time to do this stuff again).

 

[Simon Thomas]

Last 2 Inner Race

Yesterday afternoon, I dropped-by at the bearing shop and purchased 3 units of bearing. I only need 2 actually, however I better have 1 spare unit. This is normally I do in case I mistakenly spoilt it, I still have a second chance.

This evening, I should cut the outer race and take the inner race. I need the inner race to be used as my washer since it has the 2 screw on it. I just realized that I used quite a number of inner race here. It's cheaper and easy to be cut and modified as well.

I should put them back this weekend.

I managed to cut the outer race from the bearing I purchased earlier on. These are the two last inner race that act as the washer later.

 

[Simon Thomas]

The other stuff that I still need to purchase this afternoon is new suitable drill bit size. I know I have some in by tool box, but I better have some additional spare. That day I broke 1 piece which I thought can penetrate the inner race. I have learned that I cannot under estimate the strength of the inner race.

This is the stuff that I target later before doing all the works tomorrow.

 

[BriggsTwins]

OOPS! it happens, hardened steel is a bugger to work on. Um, as to the assembly for your sprocket, i like it! and what may work for you is to take some 1/8 or 3mm, and place it between your washers, weld it gently, but strongly! this will help give it the axial strength you are seeking. I looked for bits designed for hardened steels online, surprisingly they are hard to find... sigh. but i will keep looking.

To cut hardened steel with a drill bit, it must be a carbide bit, with a slow speed and lubricant. use moderate pressure and keep the part & bit cool.

http://drillbitwarehouse.com/index....&vmcchk=1&option=com_virtuemart&Itemid=600001 example

 

[Simon Thomas]

Drill Bit

OOPS! it happens, hardened steel is a bugger to work on. Um, as to the assembly for your sprocket, i like it! and what may work for you is to take some 1/8 or 3mm, and place it between your washers, weld it gently, but strongly! this will help give it the axial strength you are seeking. I looked for bits designed for hardened steels online, surprisingly they are hard to find... sigh. but i will keep looking.

To cut hardened steel with a drill bit, it must be a carbide bit, with a slow speed and lubricant. use moderate pressure and keep the part & bit cool.

http://drillbitwarehouse.com/index....&vmcchk=1&option=com_virtuemart&Itemid=600001 example

Thanks again for your advice and I take note on that. Will see what I can do tomorrow after mounting it back on the frame.

I have purchased the drill bit. The size is 15/64, the same diameter of the inner race screw. I am not sure whether it is a carbide tip type or not. The brand is "evacut" and made of "NZ". I think that is probably New Zealand.

After seeing your comment on my thread, I called the hardware shop and reconfirmed with them. They said it is not the carbide tip type. I bought it at RM8.70 (around USD2.90) only. The carbide type which is more expensive is not sold at ordinary hardware and I have to find a special shop selling this stuff. May be I have to forget this carbide tip bit first and find a simple alternative to work with the available common tools in hand.

 

[landuse]

I can't wait to see your buggy in working order again. You have put a lot of effort into getting this going again, and I hope it works for you.

 

[TorqueRanger]

You could use a cobalt bit for drilling into hardened steel but just be careful because it will snap very easy and use plenty of coolant....

 

[BriggsTwins]

AHA! i forgot about cobalt! there are a few ones good for attacking hardened steels, think i could remember a single one? heck no! lol. Refresh my memory, why are you drilling the races? to put in bigger/more set screws?

 

[Simon Thomas]

Alternative option on drill bit

You could use a cobalt bit for drilling into hardened steel but just be careful because it will snap very easy and use plenty of coolant....

Thanks for advice. I did some home work on the drill bit via wikipedia that besides carbide tip, cobalt bit can be used as well. I never try those stuffs, but this can be used in future design based on your testimonial here.

 

[Simon Thomas]

Explanation on need of drill bit

AHA! i forgot about cobalt! there are a few ones good for attacking hardened steels, think i could remember a single one? heck no! lol. Refresh my memory, why are you drilling the races? to put in bigger/more set screws?

Initially, wanted to drill hole penetrate the inner race (with hardened material) to hook the nail and pin onto the shaft. However this seemed unreliable because it may weaken or potentially break the shaft. So after review, better use the existing 2 screws to hold the race onto the shaft.

 

[Simon Thomas]

Update

Just back from fixing my buggy. It took me 2 half days Saturday and Sunday to finish the repair.

First half day Saturday was spent to fit and mount the new modified part on the buggy. Was a tiring day as stuck with selecting / sorting the right size of bearing. Infact I used 2 types of bearing manufactures which are MZD and FBJ. MZD type is slightly bigger than FBJ. This shows me that MZD bearing fit my new shaft and not FBJ.

Second half day Sunday was the spent to put the chain (which I forgot to bring along on Saturday) and run test.

It was extremely a tiring and sweating work but worth it. I will attach the photos in next posts.

 

[Simon Thomas]

Saturday's Mission

I packed all the stuffs that I need to bring and put them in my car bonnet. I noticed I have lots of stuffs to carry along. They are my table press and portable drills, grinder, spanners, welding set etc. Those stuffs are not only occupying by car bonnet but also the back seat.

 

[Simon Thomas]

At Buggy Parking Site

Upon reaching my buggy site where I parked it, have to take out all the stuffs including tools again and put beside the buggy. It is like going for camping activities, but carrying different stuffs.

 

[Simon Thomas]

Assemble Rear Axle Parts in Proper Sequence and Order

Then I took out all the modified rear axle parts from my car bonnet and start putting them on a proper sequence and order.

 

[Simon Thomas]

Modified Parts

The improvement works on my design at this stage is actually focusing on the rear axle shaft. This is the look of the modified inner race and the screws on the rear shaft after mounting them back on the buggy rear body frame.

 

[Simon Thomas]

All Parts Put Back on Buggy Body Frame

After putting the chain and all the modified parts back, including the tires.