TRF415 information needed for Yokomo belt drive conversion

[Dr. Robotnik]

Hi guys,

Another mini update. I have bought, I believe, the final parts for my project (bar a chassis plate if needed for an extended chassis).

King pins for the front MR4TC hub carriers experiment.



MR4TC roll bar set. I thought I might try and make a roll bar too.



and finally I have another matching TRF415 centre pulley



So now I just need to wait on the postman and sell parts so I can afford some electronics for this car

Cheers

Ed

[Mr. ED]

Did you try fitting the belt for size yet?

I have about 7 or more different belt sizes hanging around.
Let me know if you need another teethcount.
Those bodies look like they 'll fit very well.

[Dr. Robotnik]

Hi mate,

No I haven't received the belt, pulleys, etc that I ordered from dinball, yet. But I did receive the massive lot of Yokomo spares I needed from shodog, so cheers for that buddy

Thanks for the offer of the belt too Mr. ED I will let you know how it all goes when the parts arrive.

I have to strip my best Yokomo tonight, then clean all the spares shodog sent me, my good car and the spare car. Then I have to rebuild all 4 cars with the best bits I have available.

Should be fun.

Cheers

[Dr. Robotnik]

Well finally the other pulley turned up.

But not the entire order, as they are still waiting on the other bits (the whole 'in stock' concept seems lost on them). All in all I am not very impressed with ordering from the online Hong Kong shops. I have used three on this one project and each time the order is delayed or shipped in separate lots or something strange....

Anyway gripe over. I will drill out the pulleys at work and work out the belt size, tomorrow eveningish...

[Dr. Robotnik]

Incoming.........

I just finished turning the holes on the pulleys from 4.5mm to 5mm on the lathe (a week after I'd planned to). Last night I organised all the spares, so tonight I will hopefully be able to do the first mock up of the car to determine the belt length I need.

I am still looking for front hubs too. Don't make me make them myself people. Lol.



Oh and finally the kingpins turned up yesterday thank goodness....

[mrlexan]

On another note, I assume that the bodies came from Barry? How much did he ask for them?

[Dr. Robotnik]

So the first build last night hasn't gone well

I drilled the holes in the pulleys to 4.5mm, but I have re-drilled them correctly today.

The King pins need to be shortened.

I need two 10x5mm bearings for the front hubs.

Otherwise its all assembled. Lol.

I'll try again this evening.

[kustomizerz]

Converting 834B's chain drive train to the belt is not so easy. I used be using TRF415's pulley at first but different now. TRF415 pulley fits 4mm width belt, but 4mm is too narrow for this project. Popular belt driven 4WD have narrow belt, but they are using belt drive as reduction too. 834B's front drive system is just using for fronts, not for reduction. The internal gear's ratio what rotate drive pully is after second reduction. So its big torque acts to front drive system. That's why wider pulleys and belt are needed, it's for anti-slip.

I'm using 6mm width pulleys and belt now. The pulley is helicopter's stuff but I think it's JDM(Japan Domestic Market) product. It has same number of teeth as TRF415's, 5mm inside bore, 6mm width. That's good for 834B. Parts# is QEP16-52-1, made by Quick.

http://www.9129.co.jp/

There is no belt that can be fit to 834B in RC products. You have to find it out from industrial products. I'm using MITSUBOSHI BELTING's "STPD S3M". length is 453mm but I guess 450mm is better. In case of MITSUBOSHI, 450mm is unavailable. But other manufacture (ex.PIRELLI) may be selling that size.

http://www.mitsuboshi.co.jp/english/index.html

And some chassis modifications are also needed. 834B's nylon parts are not stiff. So the belt's tension let chassis be warped. In case of my car, I glued graphite plate on the front bulkhead's wall (bearing hole side) and change upper deck from stock plastic to graphite thing. Front side of upper deck was designed to don't twist bulkhead, that part is wider than stock and fit into bulkhead's groove. Of course main chassis must be graphite or fiber glass.

As a result, belt drive is good for the race because its low inertial mass and also good for gain chassis weight. It's easier than chain drive to do side by side race. But chain drive is much better for maintenance and easy to keep condition. So I usually run only chain drive 834Bs except for race. I will be able to upload more pictures of my BD Dog later.

[kustomizerz]

Here you are.

[kustomizerz]

Details.

[mrlexan]

Freakin' genius! Not much more needs to be said. Nice work!

[Mr. ED]

Wow,
from the looks of these parts, I can tell you don't only make smart designs but also have some very good tools and skills.
Can I ask what you do in daily live?

There's a tread to put some details on yourself, and at the same time get to know some of the peoples faces here:
http://www.rc10talk.com/viewtopic.php?f=1&t=607

[Dr. Robotnik]

Wow that is amazing, now I no longer need to guess what parts to use on my projects, thanks so much Tak!!!!

Cheers

Ed

[kustomizerz]

I'm writer and also designer. Graphic, clothing and shoes are my fields as the job. I don't have any expensive tool. I would make my cars with drilling machine, dremel and standard hand tools like handsaw.

[mrlexan]

I'm writer and also designer. Graphic, clothing and shoes are my fields as the job. I don't have any expensive tool. I would make my cars with drilling machine, dremel and standard hand tools like handsaw.

Someone has a very steady hand. Nice.