DaveBcool

I have to change the gearing on my panther as it was way too fast at the last battle.

EOT

Dave,

In my panther i used the Promaxx gear downs with 480 motors. I also obtained robinson racing products pinions. On the motor I have a 14 tooth and the output has 18 tooth, which gives me a speed of 9.78 to 10 seconds ( depends on who's doing the timing) in 25 feet. It should be 9.58 in 25 feet for the panther.

Hope that helps


Mike EOT

tomhugill

I use the impact tus with the ddg. I find with the geardowns if anything jams your tracks you end up stripping teeth, where with the impact tus theyre designed to take the extra torque so dont break

Jeff489

My Feedback: (12)

I use stock gearboxes and stock with an 8 tooth pinion (from ETO). Works great. As to the speed data...I suggest a review of RCACN

Once at RCACN's home page, click on "rules of engagement", and then look at the "AFV Data Sheet 2.1" to find the speed of the Panther, then open "Speed Guide 2.1" to learn how to scale the speed to 1/16.

DaveBcool

Thanks for the responses.

Mike

I could not find any pinions at robinson racing with a 2.3 mm bore?
Also, did you machine the output shaft down to 2.3 mm, or did you use 4mm bore pinions?

Jeff
The RCAN data was helpful.

EugeniRUS

You need to try all setups. This calculator may be of help http://jbwid.com/art74i.htm
Please remember the more teeth a pinion has got, the higher the speed.
Bigger motors provide higher speed.

EOT

Dave,

OOPS forgot that part I turned down the output to 1/8 and used this:http://www.robinsonracing.com/catalo...inion.html#six
I just put motors on the dropdowns and used a file on the output shaft, it is soft steel and goes quickly. I bought the six pack so it
would be easier to dial in the speed.
The panther has speed and torque right up until it's got 7 or 8 hits on it

Mike EOT

DaveBcool

Thanks for the info again guys.

I hate to sound like a total newbie doofus, but what does the "pitch" of a pinion mean?
I am guessing that it is the angle that the teeth are cut at?

Mike,
your link led me to pinions with a 48 pitch, does that mean that all the gears in the Tamiya TU's and gear downs use that same pitch?

Sorry to ask so many questions, I am just trying to wrap my head around this.

dlobmwm3

My Feedback: (2)

Dave,

I'll check to see if it was 48 pitch. I had a machinest drill out the pinion to 4mm. If you want, you could send it to me. I think he charged between $5 and $10 per pinion. Can't remember.

DaveBcool

Danny
I have drill press at school that I can use if I go that way.
Do you remember how many teeth you used on the output pinion?

EOT

Dave

Good luck trying to wrap your head around the pitch thing, I was thoroughly confused and had a head ache before I got it figured out
The Tamiya tank transmissions use .06 pitch gears ( metric measurement) but 48 pitch ( american) will work fine as long as you get the backlash correct. There are a couple good articles on the H.E.A.T. sight about the backlash.I've 48 pitch gears in my panther for 2 years with no problems


Mike EOT

DaveBcool

OK so I'm a total moron.
By backlash, do you mean how the gears mesh?

Unfortunately, the HEAT site is corrupt and has been down for a while.
Only the HEAT forums are working, so there is no access to the articles.

EOT

Dave

Yes backlash is how the gears mesh. If memory serves correctly 2 pieces of magazine paper between the gears should be good.

And no your not a total moron I sometimes forget that not everyone was a Master auto tech and knows that language

Mike EOT

DaveBcool

Ok, so originally I did not install the gear-downs because I was thinking it was out of my skill/comfort level and would ultimately be a headache.
And thus far it is coming true.

I received my gear-downs in the mail today, only to be disappointed that the pre-installed gear is plastic and not metal. (Like the photo on the website)

Mike and Danny,
were yours like this?
Did you replace them with metal?

EOT

Dave,

Mine are plastic and I've had no trouble with them

Mike EOT

tomhugill

DaveBcool

OK then, that is good to know.

I was worried that since it was the first gear to mesh with the pinion, that it would be vulnerable.

Now I just need to order the 18t pinion, and put it together.

EOT

That should give you plenty of torque and speed. Not as much speed as some in the H.E.A.T. club but really close to prototype speed.


Mike EOT

dlobmwm3

My Feedback: (2)

Mine are metal.

dlobmwm3

My Feedback: (2)

Dave,

Mine are Robinson Racing as well. I have either 12 or 14T pinion on the 400's and from the gear down 22T. These were with a 400 motor. Getting ready to put 480's in. I also had the Robinson Racing motors drilled out to 4mm via a machine shop in town. And the pinions are metric 32 pitch or .6 on the packaging. Hope this helps.

DaveBcool

Thanks guys.
I just came from a local hobby store which had a good selection of Robinson Racing pinions.
I brought in my panther so the store "expert" could help me figure out the pitch of the TU gears.
After meshing a variety of pinions on the TU, he felt that the 48 pitch would work best.
So I bought 16t, 18t, and 20t pinions to try.
Now I just need to decide whether to drill out the pinions or lathe the output axels.

dlobmwm3

My Feedback: (2)

[X(] Dave, your gearbox will be noisy as hell and probably won't last very long. I think you should have bought the metric 32 pitch (0.6).