DIY tranny input please?

[Thommy2Tone]

Since my TLT tranny is starting to slip it's belt, I've started looking at trannys.
BTW, I'm running a 55t lathe and I'll move up it tire size when this goes in it's new chassis.

Even the Peed tranny seems huge, so I took a stab at laying out my own.

I wanted to make it as small as possible, and keep as much clearance under the bottom as I could.

This pic shows a layout only. I used Pinion gears, and I still need to check for bearing clearance.
I can machine the 2 plates (not shown) to hold the bearings for the shafts.

Is there any reason this wouldn't work?
Any input is welcome, thanks

[Plays_with_Toys]

It'll probably be loud as hell, but it'll work. There was another TLT done up like this. I think it was entitled "project bula buster" Where he layed out his own gear set up.

The only thing I'd say is with that many metal gears, lube it up to reduce electrical chatter and reduce the noise.

Have you calculated your gear reduction with that setup?


EDIT: You might want to try and find a main gear at the bottom that isn't a pinion, that way you can run sliders more easily, since you'd need a bigger shaft than the pinion allows.

[Thommy2Tone]

Thanks Play!

Found it,

"The transmission works perfect and has a 6.0 to 1.0 gear ratio!! It's a little loud but sounds killer"

I calculated 12.6:1 (see pic)

That's a good point, I saw pinions with 1/8" holes (easier to find bearings and such) bub I didn't think about the drive shafts....yet.

[ECAMERON87]

I did this as well. Here is the link to that thread.

New gears in stock TLT tranny!

I used 48pitch gears. They are a more quiet but not as strong. They are still definately strong enough for this application. I have since then redone the transmission.... made it smaller with the motor divorced from the tranny. My final gear is now a spur gear like Plays_With_Toys suggested. The weight of the motor sits above the front axle like a 1:1 vehicle. Here is the link to that thread:

Project White Knight

I absolutely love this transmission. It took time to get the right gear ratio that I wanted. Eventually I will make a High/Low tranny as soon as a get a drill press. Then I can play fast and crawl with the same vehicle.

Good Luck.

[Thommy2Tone]

Ecamron87

What tranny ratio did you end up with? I see you'r using a reduction on the motor, and it was to slow. Did you change it again?

[ECAMERON87]

Motor with a GD600 Gear Reduction - 2.5:1

Tranny 21:1
35/10 = 3.5
35/20 = 1.75
69/20 = 3.45
----------------
total = 21.13

Motor 2.5
Tranny 21.13
Axles 2.66
-----------------
Grand total 140:1

This runs slower than walking pace. I then tried having the 10t turning the 35t turning a 20t which turns the 69t spur gear by sliding the shaft over (too hard to explain) Basically the 35t and 20t just fill in the space. The tranny ratio now sits at 6.9:1

69t/10t = 6.9

Motor 2.5
Tranny 6.9
Axles 2.66
------------------
Grand Total 46:1

This speed crawls great and I have a heavier vehicle. I wouldn't go much less than the ratio that you have. It would be too fast. In my opinion a final ratio between 40:1 and 70:1 works great. Here is another link explaining this:

Average Gearing Used?

The nice thing is that I can change the GD600 into a 3.8:1 ratio which will give me a final ratio of 69:1.

In my opinion, making your own tranny is the best way to go. I needed something narrow and tall, so I built it. You show a tranny that will produce a 33.51:1 final ratio (Assuming the TLT axle ratio is correct) This will work great if you will use a higher spinning motor than what you've got. I think that if you hook up that Lathe Motor you are going to find it too slow. Your tranny design will produce plenty of torque and slow speeds on its own. Please let us know how this turns out for you.

[Davkin]

I made my own tranny as well, but I like a little wheel speed so I use a higher ratio. I only have two gear sets in mine. I use 48 pitch on the motor to intermediate shaft, (36T 48 pitch on the inter. shaft.) and 32P gears for the final reduction. I'm using an Associated Nitro TC3 50T gear for the main gear and a standard 9T pinion. Hear are a couple pics;





David

[Madkoifish]

Seeing these I wonder how hard it would be to just use the guts of a tranny?? This would save the electrical noise from gears. And allow easy replacements.

Drilling/milling metric BB holes has got to be annoying without a mill and metric endmills. ( something I have yet to locate)
I love the idea of a DIY tranny

[Plays_with_Toys]

Holy nuts davkin. Is that your entire chassis as well?!! Where do you stick the electronics on something that small?

[romeo26]

is it posible to take the pede tranny and make it low profile?
i mean make some thing to hold it in a smaller compact case?
so its sorta like making your own tranni but using preexisting tranni internals!!

[Thommy2Tone]

Ah,

So if you use some type of spur gear, the saft can be larger so the drive shaft flanges will fit right on.

I've go some more tinkering to do.

Thanks!

[Davkin]

Holy nuts davkin. Is that your entire chassis as well?!! Where do you stick the electronics on something that small?

It's not the entire chassis, just most of it. Everything bolts to the trans except for the shocks. Here's the latest pic during my build of my new "tube" chassis for it. It had just a simple ladder chassis before this. You can see, (maybe) the ESC and receiver are just sitting on top of the trans, and the battery is just in front of it in a little cradle to the side of the motor.

This would save the electrical noise from gears. And allow easy replacements.

I haven't noticed any electrical noise in mine. In fact my crawler is considerably more quiet than the crawlers in our club with the Stampede trans.

so its sorta like making your own tranni but using preexisting tranni internals!!

That's actually harder to do because you have to use thick material and blind drill holes to hold the bearings since none of the bearing sizes you'll need will be available flanged. I only had to use two 1/4" flanged and two 1/8" flanged bearings for my trans. Using flanged bearing simplifies trans design greatly while allowing you so use material as thin as 1/8", you may even be able to get away with 1/16" thick material if you aren't bolting anything to the case.

David