PDA

View Full Version : locked differentials


kaptain Jack
05-21-2013, 05:01 PM
Can anyone advice on the best way to lock differentials on Tamiya axles
Thanks

Lmackattack
05-21-2013, 05:22 PM
you can buy a RC4wd Spool or take apart your stock diff and place one of the sun gears inbetween the other 2. this will lock it up solid just like the RC4WD spool does. I suggest doing this on the rear rear axel for better traction. Its what I did to all 3 of my trucks. on a side note for the front diff you may want to pack it with super thick grease to reduce the wheel slip action of a open diff?


just my .02

doodlebug
05-21-2013, 08:28 PM
A couple of members have used "shoe goo" for limited slip action.
Cheers, Neil.

kaptain Jack
05-22-2013, 08:45 AM
Thank you guys, all great advices!

Sentinel
05-23-2013, 08:26 PM
Just wondering if the turning circle changes much when locking the rear diffs? I've also been looking at the different options to lock the standards diffs but didn't really want to compromise steering.

Lmackattack
05-23-2013, 08:56 PM
Bob tail, no...loaded, slightly.

But a lot of this has to do with the stock 5th wheel mounting location. I have seen many tamiya kits have the 5th wheel centered over the tandems or moved rearward to give the truck,trailer a longer appearance.

1:1 trucks often run with the 5th wheel 9" ahead of center. This puts more weight up front and also aids you when backing as you can cut harder.

I run my rear rear locked for better climbing ability, and put real thick grease in the forward diff. I can drive thru grass with a load on no problem and in my opinion it's one of the best mods I have done to my trucks..

Sentinel
05-23-2013, 11:47 PM
Awesome thanks for the info. I've got thick bearing grease in the axles but I think I'll lock my rear rear.
I also think I should change the tires asap as well, the standards are pretty miserable grip-wise, I think that's half my issue.
Is there a standard that people move the 5th wheel forward on the tamiya's? Mine is still centered from stock, what's the scale measurement to move it forward, if 9" forward of center is the 1:1 normal?

sorry for the hijack kaptain Jack.

Lmackattack
05-24-2013, 02:51 PM
Its really your call on the 5th wheel placement. the further forward you go the more weight / traction will be up front and you get better backing ability. you however get less clearance between the frame and under side of the trailer when in the off road. I can measure mine but I run the stock 5th wheel plate and it locates over the tandems about mid way between the center of tandems and forward tandem. would say its about a scale 12" ahead of center. just like the real 1:1 trucks I can jack knife the truck/trailer going forward if I keep turning. backing is great


a scale 9" in 1/14 is .64" so anywhere from1/2" to 3/4 and you will look close to a 1:1 truck

I used a real thick grease and think I need something like tar to get it to not slip as easy. Locking the rear drive and better tires will do the truck wonders for traction

if you want even more traction for the off road remove your shocks and flip the spring mounting bolt/nut on the axles around so that the nuts dont hit the bottom of the frame. this gives you about another 1/4" of travel. just watch your inter axle drive shaft as it may start to bind on severe off roading.


stock Tamiya tires suck for any traction. I only run stock tamiya tires up front and on the trailer. My drives are RC4WD Roady tires as they look like more like a on/off road tire. there is a more aggressive tread from RC4WD but IMO it does not look as prototypical.

kaptain Jack
05-24-2013, 03:49 PM
I'm glad,that more people and not just me interested in info.about locking diffs.
To add to the already mentioned options,I got reply from Tamiya Canada,where the tech. also suggests thick heavy grease for the front and PLASTICINE for the rear,it allows the locking but without ''heavy hand'' and risk of breaking.

Thenewguy
05-24-2013, 08:31 PM
On YouTube a guy used jb weld on the shafts to lock them. But how well does the shoe goo work? I like to have LSD instead of full lock.

WhiteWolf McBride
05-25-2013, 12:07 AM
Jack:

Instead pf plasticine, which gets all melty when it gets warm, try that Plasti-Tak / Blu-Tak /Fun-Tak stuff... Blu-Tack on Wiki (http://en.wikipedia.org/wiki/Blu-Tack)

http://www.loctiteproducts.com/img/products/big/cntct_putty.png

We all remember it as the white or pale blue stuff the teachers used to stick sommat to the wall when they couldn't use tape or thumb-tacks. We used to pinch it as it was ~wonderful~ for pea-shooting ammo!

You can get no-name stuff in the Dollar Stores, and you can also use it for masking stuff before painting.

New-Guy, JB-Weld is a HARD Lock. Its a type of two-part epoxy. Shoe-Goo might cut loose... but I'd say the tires will slip before the Goo cuts loose, as this stuff is used for shoe-repair.

WhiteWolf

kaptain Jack
05-25-2013, 08:52 AM
Thanks, White Wolf.I will check it out.

Stuff
05-25-2013, 11:30 AM
i did the move the star gear trick. it locks solid, can't mess up the internals. Also lock up the front set of duals for tightest turning range. i had the rear locked in my last truck and the locked axle seems to make itself the pivot point when turning.

Thenewguy
05-25-2013, 11:35 AM
What's best to lock both axles or just the rear one?

RoadFlyer
06-08-2015, 08:30 PM
Can anyone advice on the best way to lock differentials on Tamiya axles
Thanks

I know this thread is a little old but I've found that just using a hot glue gun and filling the space between the three gears will lock it up solid...plus pretty easy to clean out the dried glue if you want to put it back original.

Supermario
06-09-2015, 08:38 PM
Threads are never too old! :).

I purchased a set of spider gears on ebay for cheap. Added one gear in between the existing 3 and voila. Change your mind, remove gear. One set of gears locked the rear diffs on 3 of my trucks. Just my 2 cents....

I like the glue gun idea but don't forget, shoe goo works. Its tried and tested, also non permanent.

RCP57
06-09-2015, 09:05 PM
I know this thread is a little old but I've found that just using a hot glue gun and filling the space between the three gears will lock it up solid...plus pretty easy to clean out the dried glue if you want to put it back original.

I use this method as well. It even has a bit of give to take the shock out of the assembly.

Lmackattack
06-09-2015, 09:08 PM
Regarding locking one or both axles

It depends how much off roading you want to do. My experience says when you go into soft dirt or gravel of any kind you need both locked in. I find that when you lock in just one axle you still will get stuck when that axles has no weight on it. The Tamiya Suspension is very poor for traction. The stock springs are way to soft to keep weight balanced across both axles. Most times if your truck has a trailer on back the trucks frame rails are touching the axle stops. this means that when the truck encounters bumps only the axle that is touching the frame has good traction. the other is just floating so to speak. If both axles are locked you at least always have solid traction from one axle when traveling over bumps. I have witnessed guys with only one locked axle in the dirt and they still spin out fairly easy.


Thats my .02

bigford
06-09-2015, 09:56 PM
I wish my KW had locking diffs!! had to get pulled out of a soft dirt job.
point is I just dumped 80,000 lbs of gravel and as I pulled away the wopper hopped
spun the wheel and buried me. I hate one wheel peelers
inter axle was locked in

Lost_ Frequency
05-31-2016, 01:19 AM
BigFord you don't have diff locks in your 1:1?

bigford
05-31-2016, 04:50 AM
No when the rears were rebuilt the boss saved $4000. by not installing the lockers.

jack van
05-31-2016, 11:50 AM
i have purchase the 2 rear axles from rc4wd but i am have a heck of a time trying to get the 2 cables and servo plumbed in and working right i also have servo disconect for trailer on truck

Lost_ Frequency
05-31-2016, 01:12 PM
No when the rears were rebuilt the boss saved $4000. by not installing the lockers.

Awe man and with the stuff you haul that's got to be a pain in the *** good thing you don't have to back into places like we have in Michigan, my company I worked for did demo of abandoned houses in Detroit so you have to back into soft dirt lockers and inner lock is needed for that

Just_Build_It
11-04-2016, 03:39 PM
I was tossing ideas around about how I could lock the KH diff's. Here's where the duhh moment hit me. I have a pair of Hilux 4x4 axles collecting dust so I began to operate on the front locked diff. Tamiya uses the same carrier for their axles! I simply transplanted the carrier to the KH differential. It locks the shaft with a grub screw so I have to make a flat side for the grub to grad the shaft in the carrier. It is completely reversible without any use of glue or welds. Just thought I would share this for anyone looking for ideas.

skeeter
07-23-2017, 12:10 AM
DAM, I was going to mention the gear trick, but saw someone else here already beat me to it.

frizzen
07-23-2017, 07:37 PM
I just remembered another limited-slip option a lot of 1/10 scale crawlers run where Open doesn't work, but you don't want turning radius of Spool.

Silly Putty.
Clean the carrier and gears. Figure out how many eggs you need to pack diff. To loosen the amount of lock, add silicone shock oil. Work in a couple drops of oil to the putty, assemble enough to test it. Go slow adding oil, or you'll have to add more putty to thicken again.