Scratch building a planetary gear box

This board contains easy-to-do fixes on your new tanks from stock. This will hopefully help beginners to get the accuracy they want from their models.
walter
Sergeant
Posts: 567
Joined: Fri Mar 10, 2017 11:53 am
Location: Geelong Australia

Scratch building a planetary gear box

Post by walter »

Having build and modified a number of tank gear boxes, looking for the ideal gear box and have come to the conclusion they more or less do all work. It is just a personal preference.
One though eluded me,the planetary gear box. Every time I went into its technicalities it always turned out to be in the to hard basket. Mainly obtaining the right sized ring gears. I never could find them small enough for what I wanted.
Till one sleepless night I all worked it out how to make my own ring gear using my little bench milling machine. To my amazement it was quite simple.
For the gear boxes in my tiger2 I used geared motors 50:1 and later 60:1 . They both worked well the 50:1 being a touch fast.
When I had the geared motors apart,looking at those tiny gears and visualizing that the whole workload is carried just by one tooth, made me feel a bit uneasy. Where else on a planetary gear box the load is carried by 3 teeth. Quite more appealing.
All my different geared motors are interchangeable with my gear box housing. So my planetary gear box had to be interchangeable as well.
Working out all the measurements was at times hit and miss, some parts hat to be made 3 times till they where right.
But in the end when I assembled them and they where working very well it was all worth it.
The performance of the gear box is quite astonishing.It starts working at 1.5 volt and it's strength is unsurpassed.
I planed to have 3 gear cages one 1:5 and two 1:4 in it,but found for the motors I was using the tank was running to slow.So I used only two gear cages to get the speed I wanted.
The process to change the reduction of the gear box is so convenient just add or remove a gear cage. It allows me to use a greater variety of motors.
Of all the gear boxes I own the planetary one is my favored I almost could say my ideal gear box.
Walter
walter
Sergeant
Posts: 567
Joined: Fri Mar 10, 2017 11:53 am
Location: Geelong Australia

Re: Scratch building a planetary gear box

Post by walter »

This is how I made my ring gears
Attachments
IMG_20190928_094632 (2) (Small).jpg
IMG_20190928_094632 (2) (Small).jpg (87.82 KiB) Viewed 4370 times
walter
Sergeant
Posts: 567
Joined: Fri Mar 10, 2017 11:53 am
Location: Geelong Australia

Re: Scratch building a planetary gear box

Post by walter »

Parted into individual housing sections.
Attachments
IMG_20190928_094804 (2) (Small).jpg
walter
Sergeant
Posts: 567
Joined: Fri Mar 10, 2017 11:53 am
Location: Geelong Australia

Re: Scratch building a planetary gear box

Post by walter »

Motor end housing.
Attachments
IMG_20190928_095123 (2) (Small).jpg
IMG_20190928_095123 (2) (Small).jpg (71.55 KiB) Viewed 4365 times
walter
Sergeant
Posts: 567
Joined: Fri Mar 10, 2017 11:53 am
Location: Geelong Australia

Re: Scratch building a planetary gear box

Post by walter »

Drive end housing.
Attachments
IMG_20190928_095123 (2) (Small).jpg
IMG_20190928_095123 (2) (Small).jpg (71.55 KiB) Viewed 4364 times
walter
Sergeant
Posts: 567
Joined: Fri Mar 10, 2017 11:53 am
Location: Geelong Australia

Re: Scratch building a planetary gear box

Post by walter »

Motor end with motor.
Attachments
IMG_20190928_094938 (2) (Small).jpg
IMG_20190928_094938 (2) (Small).jpg (80.79 KiB) Viewed 4363 times
walter
Sergeant
Posts: 567
Joined: Fri Mar 10, 2017 11:53 am
Location: Geelong Australia

Re: Scratch building a planetary gear box

Post by walter »

All the parts for the gear cages.
Attachments
IMG_20191027_121358 (2) (Small).jpg
IMG_20191027_121358 (2) (Small).jpg (81 KiB) Viewed 4362 times
walter
Sergeant
Posts: 567
Joined: Fri Mar 10, 2017 11:53 am
Location: Geelong Australia

Re: Scratch building a planetary gear box

Post by walter »

Drill jig for gear cage housing.
Attachments
IMG_20191027_120206 (2) (Small).jpg
IMG_20191027_120206 (2) (Small).jpg (68.59 KiB) Viewed 4361 times
walter
Sergeant
Posts: 567
Joined: Fri Mar 10, 2017 11:53 am
Location: Geelong Australia

Re: Scratch building a planetary gear box

Post by walter »

Another view.
Attachments
IMG_20191027_120312 (2) (Small).jpg
IMG_20191027_120312 (2) (Small).jpg (57.79 KiB) Viewed 4360 times
walter
Sergeant
Posts: 567
Joined: Fri Mar 10, 2017 11:53 am
Location: Geelong Australia

Re: Scratch building a planetary gear box

Post by walter »

Gear cage sides drilled.
Attachments
IMG_20191027_153810 (2) (Small).jpg
IMG_20191027_153810 (2) (Small).jpg (76.53 KiB) Viewed 4359 times
Post Reply

Return to “Things to fix on your new tank”