Greasing Gearboxes
 

Can someone post me a picture of how it needs to look? I would appreciate it.

You'll get a bunch of opinions on this Shannon. For the most part you want a thin oil on the shaft and shaft bearings/bushings like 3 in 1. Then a plastic safe white lithium grease for the fast moving gears and gear oil on the slow moving gears. Never too much or it acts as a magnet for dirt and debris. For the most part I before I install a gearbox I wd40 it out, run it in an oil bath, clean it up and apply lithium grease on the faster moving gears as oil won't stay. You really just want the gears to look "wet" not gooped with lubricant.

I've been using tamiya ceramic grease on mine.

That's fine. Just keep an eye on them and don't let the gears get dry.

I use white lithium grease on all my RC (Tanks, Mini 8ight, and Trekker) Everything works great...

I was going to try Corn Head grease, it stays put, works great in lawn mower gear drive transmissions, and of coarse high speed combine corn heads.

Sounds good. Thanks for the advice all!

I strongly support the use of an oil that has a high temp rating and will not attack plastic.

If you can handle it, make a cover for the gearbox assembly to keep dirt and other debris off PLUS, install some sponge material at the axle hole and poke the axle shaft through it. This keep dirt from entering at that area.

http://static.rcgroups.net/forums/at...7-HPIM4496.JPG

http://static.rcgroups.net/forums/at...5-HPIM4500.JPG

Remember, grease will attract dirt and is more difficult to clean off than oil, so oiling periodically is better than one application with grease which is more suited for roadwheels and idlers where it's a sealed system.





Jeff

What material is that Jeff ?

The 'cover' over the gearbox? It's just a thin sheet of Plastruct styrene I bent and cut as a template... I have brass sheets I will use as the final material (might look better?) with weather striping foam around the edges to help seal.





Jeff

Its pretty sturdy? when i think of styrene it'll break apart easily.

Well, I don't know how Evergreen sheets of styrene are (only have that in strips and tubes) but Plastruct sheet is bendable up to a certain thickness. Most of your typical injected molded/slide molded styrene from plastic model kits is kinda fragile. This stuff is not.

Besides... there are members here that have build covers for their gearbox assemblies out of aluminum and they look so much better than this rather crude example, but it is very effective!






Jeff

This is the best investment of PM (preventative maintenance) you can do for your tank.

It is not just one "greasing" step. All gearboxes need to be oiled, lubed and covered for proper preventative maintenance. On a used tank it is 1) Clean, 2) apply machine oil, then 3) grease/lube. The first step is to peel back my TU/gearbox cover and remove the dark old grease. Use no solvents or wire brushes. Use Q-Tips and gun cleaning patches (Hoppes)/small rags on tweezers. Clean them thoroughly at least once a year. Then use a fine machine oil (never WD40) to oil the shafts and bearings. Singer sewing machine oil is my favorite. It has good capillary action to get under the gears where grease will not. Several drops on the shafts near each gear and the end bearing/bushings. Then turn the tracks by hand (DO NOT RUN THE MOTORS...FIRE HAZZARD) to work in the oil. Then spray in (if you have aerosol can with long red applicator tip) or brush in, white lithium grease on the faces of all the gears. The white lith. grease grows darker with age & use. Then turn the motors by hand to work in the grease evenly. DO NOT RUN THE MOTORS. Then reinstall the TU covers adding extra or new tape where needed. I try in incorporate a clear piece of plastic into each TU cover whenever possible. That allows for a quick inspection without removing the TU covers. Jeff and I both seal the TUs at the out-put shafts with foam whenever possible.

Be sure the motor & other wires are neat and safely out of the way from rubbing or shorting out. If I build it they should be very secure...but things move sometimes. This should be done once or twice a year dependent upon use. Add extra grease before each battle. The large plastic gears spin fast and are under low stress/torque so they are made of plastic. The middle/intermediate gears and under more stress but rotate slower so they are made of brass. The final gear on the out-put shaft is hi stress/torque but very slow speed so it is made of iron/steel. All need BOTH oil (shafts & bushings) and grease (gear faces).

Here are some pix for your reference Shannon. The first 4 pix may be of your tank when I prepped it for you last year.

Tamiya Tiger I
http://www.rcuniverse.com/forum/atta...mentid=2157047http://www.rcuniverse.com/forum/atta...mentid=2157048http://www.rcuniverse.com/forum/atta...mentid=2157049http://www.rcuniverse.com/forum/atta...mentid=2157050
Tamiya KV 1 Out-put shafts seal:http://www.rcuniverse.com/forum/atta...mentid=2157061
Hooben Elefant:
http://www.rcuniverse.com/forum/atta...mentid=2157062http://www.rcuniverse.com/forum/atta...mentid=2157063
Tamiya Sherman:http://www.rcuniverse.com/forum/atta...mentid=2157064
Taigen Tiger I:http://www.rcuniverse.com/forum/atta...mentid=2157051http://www.rcuniverse.com/forum/atta...mentid=2157052
H L Stug/Pzr IV converted to Tamiya IR:http://www.rcuniverse.com/forum/atta...mentid=2157057
Tamiya Pershing:http://www.rcuniverse.com/forum/atta...mentid=2157058http://www.rcuniverse.com/forum/atta...mentid=2157059http://www.rcuniverse.com/forum/atta...mentid=2157060

Tamiya Panther:

http://www.rcuniverse.com/forum/atta...mentid=2157301http://www.rcuniverse.com/forum/atta...mentid=2157302
Here is how my Danville loaner M4 Sherman looks after a few months on the battlefield. You can see the accumulation of dust & dirt and how it clings to oily surfaces. http://www.rcuniverse.com/forum/atta...mentid=2157303http://www.rcuniverse.com/forum/atta...mentid=2157304

Here my covers have been pulled back and you can see how the dirt has not entered the TUs by the top or thru the out-put shafts seals that I use.
http://www.rcuniverse.com/forum/atta...mentid=2157305http://www.rcuniverse.com/forum/atta...mentid=2157306
Just clean out some of the old and add some new oil then grease and you will have trouble free TUs for years to come.

This is the best investment of PM (preventative maintenance) you can do for your tank.

Very good post Bob thanks for all that information!

The one tip I would heavily emphasize is to NOT over oil the motors. Just a simple drop, pull the shaft in and out, roll the motor over then add one more and then THAT'S IT! Both ends... the pinion and the 'com' end.

I built motors when I slot car raced and this applies here even with can motors is that oil will kill the performance and life of a motor if it gets into the brush area. :o




Jeff

Thanks Shannon,

I was a mechanic before being a cop and in that 35+ years I've seen how simple PM can be. I cringe every time is see a uncovered RC Tank Gearbox/TU. Or worse... one that is not oiled & greased at all. I know we all rather spend out hard earned dollars on upgrades or new RC.... than buying parts we could have saved from senseless wear & damage. If get your battery wires or DMD motor wires going into a pinion gear and you could ignite a fire. It could even happen while sitting on a shelf or during transport. Super neat wiring like I posted above (AKA... wire hygiene) are yet another way to avoid trouble. A loose screw into a TU or pebble can also destroy them quick.

The PM time is well spent. Jeff is also on target with the over oiling. Soak up any excess oil or prop the far end up of the tank and leave it tilted on a rag overnight to drip off.

Helpful hint: Never grease or oil your turret rings, turret sliders/rollers. The benefit will be brief as the oil will attract dirt & dust and soon do more harm than good. A drop of oil on the elevation or rotation motor pinion gear is good....but do not oil and further.

I personally, weld all my slipper clutch gears solid on Tamiya tanks elevation & traverse units.
http://www.rcuniverse.com/forum/atta...mentid=2157536


The recoils should be lubed on the barrel mount slider trolley, and the brass center bolt.
Tiger.....http://www.rcuniverse.com/forum/atta...mentid=2157537 most other Tamiya recoils....http://www.rcuniverse.com/forum/atta...mentid=2157538
Oil the recoil reduction gears very lightly on all ... but NOT on the Tiger I. It is all open and best left dry.

The track idler wheels should also be lubed/greased at least once a year (white lithium or Tamiya ceramic is great) or more as needed.
Small Tank Battalions get a tube....http://www.rcuniverse.com/forum/atta...mentid=2157534
LARGE TANK BATALIONS need a tub....http://www.rcuniverse.com/forum/atta...mentid=2157535

I hope this saves you all some trouble and enhances your tank fleet.

Bob, rctankcommand.com






Bob, RCTankCommand.com

i like the foam installation around the drive shaft never thought of that but i do have some covers on the gearboxes on my T-34

http://www.rcuniverse.com/forum/atta...mentid=2157542http://www.rcuniverse.com/forum/atta...mentid=2157543http://www.rcuniverse.com/forum/atta...mentid=2157544http://www.rcuniverse.com/forum/atta...mentid=2157545http://www.rcuniverse.com/forum/atta...mentid=2157546

Jeff i got that styrene sheets you use.

Bob,

Which hoppes do you use? I'm ordering supplies. Also, I emailed ya some additional questions.

Thanks

Oh good! Time to get crazy with the styrene. :cool: I may leave mine with the white stuff too as I am running out of time to stop and cut brass sheeting although I do think this way will increase any gear noise because now it's more of a box by volume than an individual piece over the gearbox.

And Bob is right about wiring hygiene because when I see a wad of wiring going all over the place just waiting to get caught up in the turret mechanism or the gearbox I always ask: "Where's the marinara sauce at?", meaning it looks like a bowl of spaghetti.

Here's my Pershing right before replacing the Tamiya connectors: http://i12.photobucket.com/albums/a2...9/HPIM1260.jpg

Like Bob, I spent many of years in electrical troubleshooting & repair, installing customers sound systems and audio enclosures, replacing dashes in $70,000 BMW's, reupholstering 6 piece Recaro seats, fuse box work as well as A/C system analysis and repair, suspension & steering, alignments and brakes. ALL ASE Certified. :p


Show us your styrene results!




Jeff

Great write-up for greasing the gearboxes. One question: with the plastic covering the the motors, have you noticed a problem at all with heat or overheating, particularly when driving outside?

I've been sealing them off like that for many years. It is cheap simple and very effective. Make a small hole with a punch, soldering iron or Exacto. Keep it is small as possible too for a tight fit.
It is one thing that I noticed very quickly at Danville. If the field was dry and dusty.... the grit got every where in the tank.

One of the biggest holes in the hull was the out-put shaft at the drive sprocket. The grit didn't effect the electronics and such, but I knew it was a death sentence for the TUs. The guys at NEAD and Danville that did lube well, often had grease thrown about in the tank. Just look at the undersides of the hull on your HLs & Taigens tanks. And that is just grease flung off, not oil.


BRW, I have always liked your clear covers. That way you can assess the lube condition very easily. I always try to incorporate a clear plastic section into my TU covers.

Hoppe # 9 Shannon. Just dampen the gun cleaning patch...not drippy wet. The gearboxes don't have to be spic & span...just clean of debris and dirty grease/oil pal. The Hoppes gun oil is a great lubricant too for TUs. I just have a whole lot more Singer sewing machine oil around left over from an estate sale.

http://www.rcuniverse.com/forum/atta...mentid=2158029

I like how neatly you reduced the size of the speaker Jeff. Did you have that Pershing at Danville the last time you came? I just remember your M4 the best.... Oddball"s Sherman. Too cool.,,,LOL. See it in action here at the begining of this crude video. Video: https://www.youtube.com/watch?v=isU_GiH4qFA

A strong mechanical or automotive background is certainly a boost in this hobby.

No problems at all. Unlike planes, cars and boats,,, we are not running the motors continuously or for long periods. The TU framework and tank aluminum bodies also serve as a heat sink to dissipate heat. Good question!