RC Tank Warfare community hobby forum

Hello Guy's, here is the deal both MY kt'S have wheel wobble, I purchased the after market bearings and just thought some one may of done this upgrade and has some advice, Just shocking how bad they are and Tamiya KT's at that. Really disappointing considering the Kit cost for a King Tiger. Saxondog

Hi,

I was surprised to read this and I've been thinking about it for a few days. I can equate it to what happened on my WaSan T34 when I first got it. Though the Tam has much better bearings (the T34 really doesn't have any) the common factor is both have large wheels. Large wheels put more stress on the bearings than smaller roadwheels, particularly in tight turns. More stress = more wear. More wear means crap gets in which equals more wear.
If you build heavy, then the wear would probably be accelerated. Water probably won't help either and sand can be a killer.

I wore out the original bearings on the T34 within weeks and noticed that the holes in the wheels and the axle shafts had worn tapered so I rebuilt the suspension using ball races and metal suspension arms.

The Geppy was also converted to ball races and that runs beautifully.

I've never done the job on a KT so I can't give you any tips, sorry!

It would be interesting to find out if this is a known fault on the Tiger 1/2. If so it might be worth considering this part of the "standard" upgrade path for all large wheel Tam tanks - including the Panther and KV - if they are built heavy.

Wouldn't mind betting you notice quite a difference before and after the bearings are fitted!

Just a few of my thoughts on wheel bearings!! Do let us know how you get on.

Peter

excellent train of thought,the exact issue plus one more. My Kt;s are older models the Porsche being 10 years +_a year and the Henschel is the same design. The newest kit for the KT has replaced their bushings with ball bearings but they are open not sealed so the elements you have detailed will be a negative factor in their length of usable service.

I have pirchased the better set of bearings, ETO has them for considerably less than other vendors and they seem to be of the same quality. My Mate Dietrich has both sets offered as we are modifying our KT's the same way. So the only issue at hand is the non sealed bearings improve the stability of the wheels which helps alot.

Also another member has an traction,idler arm modification that works very well as the tensioner on the KT's is a sprung steel type spring,about 170deg. coiled piece of metal that is connected through a slot to the idler arm shaft. But it does not stand the test of time.

The design has to short an arm which allows the tracks to become very slack during stressful situation like stopping on a incline and the having to go full power. The spring bottoms out and the tracks can miss the drive sprocket notch and roll off;These older lits were carpet runners,my Tiger S13 with the Asiatam lower hull and upgraded drive at 20lbs. will climb over anything,I have even chained a stock Jagdpanther to the Tiger,cranked the Jagdpanther up to full track spinning speed and the Tiger dragged the Jagdpanther backwards. My Porsche King Tiger is a tank I have wanted and was luck to be able to acquire one a few months back. This will be the tank to beat my Tiger in performance off road. I will keep you in mind and your observations. Thanks Sax

I fitted bearings to my KT bought from http://www.expotools.com" onclick="window.open(this.href);return false; in uk. I've forgotten the right size now but they were sealed and a real bargain.

I strongly recommend this mod. You don't need to buy fancy fitting kits - I centred mine then fitted a collar and epoxied it in place.
The other point worth noting on the KT is that the shafts are longer than most other models because the body is wider so there is more 'whip' in the shaft tending to drive the original 'bearing' oval in time.

Hi Sax I've done this conversion on my Tamiya KT. I got my bearings from a UK company called technobots. I got the idea from a post by servoblast I think it was on panzer forum. He's done it on both the older and newer KT wheels and it works a treat. The bearings were a drop in fit and can be fitted either during or after construction. The bearing size I used for the newer KT was :-

18 x 4mm x 8mm unflanged bearings
18 x 4mm x 8mm Flanged bearings

For the older model it's 18 x 4mm x 8mm unflanged bearings and 18 brass or steel washers with 4mm hole and 9.2 to 10mm outside diameter. Thickness is to be no more than 0,8mm. Replace the bushing with a bearing then put a washer over the bearing. Put wheel assembly together and check for binding. If there is binding replace with a thinner washer or thin down existing one. Some play will still be evident but a lot less than with bushings. Hope this helps.
Alan

Thanks Tankman, The bearings I have came from Bob @ ETO Armor. I am fitting to my Older Porsche King Tiger first then the Henschel version which is an older KT as well.

The information you provided is very helpful and the washer issue was information I did not have, Thanks Alan

cheers Blake