I'm impressed!
Thanks AJ-MJ
A knowledgeable person told me that my original gearbox design was going to be a problem. The gear reduction was inadequate. With my configuration, the Willys would've run at 30mph.
He was very helpful and provide me with a fantastic spreadsheet to compute the gear stages and reduction. He said my goal should be between 3 and 5 mph.
I also need to build the gearbox in such a way that it will fit in the avalaible space without moding the visible parts of the Jeep.
So I came up with this gear arrangement.
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Here's a sliced view which shows I have enough room to build a housing around the gear that will fit inside.
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With this new arrangement in conjunction with a 55T motor and a differential gear set up of 13 teeth /26 teeth, the Willys at full throttle will run at 4mph with 110mm tires.
That is the only thing that will clash, the tires will have nothing in common with the original. I have not found RC tires that mimics the Willys tire look.
Last edited by bluesblooded; 01-30-2021 at 04:17 PM.
35 mph?!? Too fast! Too fast! Once you dial in your speed, remember that this thing is supposed to go the same "slow" fast uphill, downhill, underwater, over rocks, in mud, and the same fast driving in what you up there call real snow... Torque and traction and weight balancing, baby, so it does the same thing in all conditions! It is 4wheel drive, right? (So glad you are back at this)
Last edited by 5JeepsAz; 01-30-2021 at 07:25 AM.
bb.... so it's got Ludicrous mode? It is quite possible their are a few who will aspire to that!
Slow is good, I have to walk by it. Not planning to build a F1. And yes we have real snow here, so 4x4 is a must. I envy your dry hot weather. Still two and half months before it's all melted. So is Cindy home yet?
Maybe, but I doubt it will go fast very long. Everything being plastic, I bet the gears won't sustain the heat very long. We will end up with gearbox pudding.
Ludicrous mode. A must! No, she's been all stop due to pandemic. They should be back to it momentarily.
Might be this week! Hey, so last time you had to futz with the material. What are challenges with materials for gears?!?
Thanks bmorgil, it does look great in chrome.
The main problem is toughness and heat resistance. There is some material that are most suited for this.
Here's a table of different material with their characteristic.
https://www.simplify3d.com/support/m...mE7NUOT0Uf_NxU
So the best filament would be Polycarbonate. I myself will start with PLA. The strength is probably sufficient. The problem will be the heat. But I personally do not plan to run the Willys that long. I think it will be all right. But an RC enthusiast would be better served with Polycarbonate.
Making some adjustments to the current designs.
The bearing would not fit due to the required supports for printing. So I added a recess so the bearing fits.
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Here is what the wrong versions looks like. The case will not close without scraping the inside of the bearing recess. Other than that it is functional.
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My original design was to install the gearbox inside the frame. That would prove to be a problem if the gearbox breaks. It would require a total dismantle to get it out. I created brackets in the frame that the gearbox will sit on. This way I will be able to remove screws from underneath the car and slide the gearbox out of the hood.
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