911 RSR TT-02

[An_RC_Guy 90]

This is my build thread for my Tamiya 911 RSR TT-02 kit. I'd like to mention that I received this kit from my wonderful Aunt and Uncle as a gift in return for helping fix my uncles sports car. This will be a bit of a longer build as I'm still making it and changing things as I go. Hope you all will follow along and enjoy the build!

[BuggyDad 1618]

Will follow with interest. I think this shell is gorgeous and would love to build one with a few chassis hop ups. Been TT-02 curious a while. Seems a bit odd to me they don't spec it with at least CVAs, bearings and some upper arm adjustment. 

I've got the same shell on order to put on my XV-01.

[Rally! 142]

Very nice, and a beautiful subject. I will follow with interest as it's a TT-02. Enjoy your build.

I installed that TT-01 turnbuckle set (53662) on my TT-02 and snapped both the longer metal ball studs, but it was probably my fault. 

[An_RC_Guy 90]

As per the instructions, I started with installing the center driveline and both differentials. The front is the stock kit gear diff, but the rear is the Tamiya 53663 TT-01 ball diff. Accompanying the two is the Tamiya aluminum propeller shaft and joints. I went ahead and cut out small pieces of soft foam and put them into the the cups to keep the propeller shaft from jiggling around as I had seen the same thing done in other builds. I also went ahead and used full ball bearings in this kit instead of those odd plastic bushings, one would have thought it'd come with all be metal bushings at least. I secured the driveline with the plastic keeper and fastened it down with some titanium hex head screws from Yeah Racing. I don't know if those screws are actually titanium or not, I mainly just wanted to have a hex head screws on a good portion of the car instead of the phillips head screws. RCmart just so happened to have these and not the Tamiya stainless steel set, but I'm not being picky.

[An_RC_Guy 90]

Next part of the process was installing the upper and lower control arms, dogbones, axles, and hubs. I used the Tamiya adjustable arms as opposed to the regular solid arms so I can do camber adjustment. I've heard just a handful of guys saying these arms aren't good and that they snap, but personally I don't see how that would happen unless you really smack your wheel into a wall when you're racing. I used the stock dogbones and axles because I felt they were sturdy enough for the super stock motor, it'd be different if I was throwing brushless power at them. One thing I feel stupid about is that I put the long screws into the rear lower control arm mount without putting the rear plastic guard on, this caused the screws to go into the diff and wedge it. It didn't damage the diff gear, but I did have to use a hobby knife and get rid of the protruding plastic bits. Once I did that and put it all together I realized that I put the rear diff in backwards and had to take the whole thing apart to flop it around.

[An_RC_Guy 90]

Pushing forward, I've gotten the CVA super mini shocks all constructed and boy were they an upgrade compared to the pogo sticks you get in the kit. I went ahead and used the two hole pistons and the oil that came in the box, I figured it was a good middle ground. I've been waiting to use these shock pliers since I got them and they fit the bill perfectly when building these, no scratches on my stanchions. Another hop-up that I got was the Tamiya on-road spring set. I used the soft on the rear of the car and medium on the front, but from the tuning guides I'm reading now I might want to switch that around. I did end up using the thinnest adjuster to get rid of the slight play that the spring had when the shock was fully extended.

[Re-Bugged 8236]

That’s a nice collection of bit & pieces to play around with over the holidays, enjoy it 👍🏻

[BuggyDad 1618]

Looks fun. Enjoy? 

A question - why those adjustable arms vs turnbuckles? 

[An_RC_Guy 90]

54 minutes ago, BuggyDad said:

Looks fun. Enjoy? 

A question - why those adjustable arms vs turnbuckles? 

From an engineering standpoint the adjustable arms are the only way to go unless there's a way to fit TT-02S suspension arms and knuckles. You could probably get away with putting turnbuckles in the rear, but there's not a straight path from the bulkhead to the hub for one to mount. The front is pretty much a no-go because the upper arm and lower arm work to stabilize the steering knuckle. The Tamiya engineers didn't use a steering knuckle inside a hub on the TT-02 like most competition kits and instead used large pivot balls. Noting this, a plain turnbuckle would cause the knuckle to fop around and in turn give you some interesting "active caster angle". The Tamiya adjustable arms are pretty much the only option for the standard TT-02 unless you want to extensively modify the setup, and at that point you might want to look at just getting the TT-02S or a different chassis.

 

[BuggyDad 1618]

1 hour ago, An_RC_Guy said:

From an engineering standpoint the adjustable arms are the only way to go unless there's a way to fit TT-02S suspension arms and knuckles. You could probably get away with putting turnbuckles in the rear, but there's not a straight path from the bulkhead to the hub for one to mount. The front is pretty much a no-go because the upper arm and lower arm work to stabilize the steering knuckle. The Tamiya engineers didn't use a steering knuckle inside a hub on the TT-02 like most competition kits and instead used large pivot balls. Noting this, a plain turnbuckle would cause the knuckle to fop around and in turn give you some interesting "active caster angle". The Tamiya adjustable arms are pretty much the only option for the standard TT-02 unless you want to extensively modify the setup, and at that point you might want to look at just getting the TT-02S or a different chassis.

 

Interesting. The S/SR are more different to the base chassis than I realised. 

[An_RC_Guy 90]

On 12/22/2022 at 5:53 PM, Rally! said:

Very nice, and a beautiful subject. I will follow with interest as it's a TT-02. Enjoy your build.

I installed that TT-01 turnbuckle set (53662) on my TT-02 and snapped both the longer metal ball studs, but it was probably my fault. 

Welp, you aren't the only one who sheared off a ball stud. Thankfully it was only one, sadly what was left I couldn't get out of the steering knuckle. I already ordered another parts tree to get that steering knuckle and another turnbuckle set to fix it, so it is what it is. I think it might be worth my time to find a thread tap and make threads in the arm so I don't ruin another one. This won't stop me from finishing everything else in the kit though, so I got the steering servo installed. I ended up going with a Futaba S-U300 digital servo I think for around $18 on Amazon, seemed fair and I trust their quality. I do like the Tamiya high torque servo saver, even though the 3 springs are a bit of a pain to get on, it seems solid and no slop at all compared to the loosey goosey kit servo saver. In the middle of things I forgot to show the super stock RZ motor and the Yeah Racing adjustable motor mount. I had planned to use the RZ in my F104, but it didn't work with the ESC, so now it's going in this. I really enjoy the motor mount since it'll act as a heat sink and allows for easier adjustment.

[Rally! 142]

51 minutes ago, An_RC_Guy said:

Welp, you aren't the only one who sheared off a ball stud. Thankfully it was only one, sadly what was left I couldn't get out of the steering knuckle. I already ordered another parts tree to get that steering knuckle and another turnbuckle set to fix it, so it is what it is. I think it might be worth my time to find a thread tap and make threads in the arm so I don't ruin another one. This won't stop me from finishing everything else in the kit though, so I got the steering servo installed. I ended up going with a Futaba S-U300 digital servo I think for around $18 on Amazon, seemed fair and I trust their quality. I do like the Tamiya high torque servo saver, even though the 3 springs are a bit of a pain to get on, it seems solid and no slop at all compared to the loosey goosey kit servo saver. In the middle of things I forgot to show the super stock RZ motor and the Yeah Racing adjustable motor mount. I had planned to use the RZ in my F104, but it didn't work with the ESC, so now it's going in this. I really enjoy the motor mount since it'll act as a heat sink and allows for easier adjustment.

 

Oh, man! Sorry to see that. I started a thread about it and some people added some suggestions on what to do.

I showed my local hobby shop, and one of the guys there thinks the hole might be a bit too small. He also suggested maybe using some grease just to make it easier on the screw.

 

[Rally! 142]

Did you notice any difference in steering slop/fit with the low friction step screws?

[An_RC_Guy 90]

On 12/23/2022 at 11:04 PM, Rally! said:

Did you notice any difference in steering slop/fit with the low friction step screws?

Well I haven't used the stock step screws, but I like the low friction step screws. They're really smooth and the arms don't rock back and forth on them, but there is a little play going up and down that can be sorted out with a thin shim. I don't think the little bit of up and down movement will affect much if anything, but take my opinion with a grain of salt.

[An_RC_Guy 90]

Well I was able to get all the electronics in the car but it's a jungle of wires. I'm going to remove the leads of the Tamiya motor, cut the esc motor leads to size, and solder directly to the solder pads. I might also try to shorten the battery leads since it's just an xt60 connector. I'm keeping the xt60 and using an adapter to a Tamiya connector in case I want to go from NiMH to lipo. I can't do much about shortening the servo wires and such so I'll just ziptie those. I have my new turnbuckles, but I'm still waiting for my new steering knuckle to arrive. Next step is installing the body posts and getting the body trimmed and ready to paint, also glue the tires to the rim before I forget to. I have my new turnbuckles, but I'm still waiting for my new steering knuckle to arrive. 

I put the uncut body on the chassis and realized I made the longer wheelbase chassis setup, I had to dismantle everything again and flip the rear arms to make it shorter to fit the body. At the same time I swapped the shock front to back so I had the softer springs on the front.

[An_RC_Guy 90]

Well I made substantial progress in getting the car in a running state, my new steering knuckle showed up in the mail today! Interestingly enough the parts tree for it come in a pack of two, hopefully I won't end up needing that second parts tree in the future...    Anyways, I decided that I was not going to snap another ball stud and mess things up, so I bought a thread tapping bit at the hardware store. Just for everyone's knowledge the tap is a 3mm-0.50 for the ball studs and it also appears to be the same for the turnbuckle threads. Once the plastic was tapped the ball stud went right in with no issues. 

Once I did all that I aligned the front end and putt all the electronics in (yes I know, the wiring is still a furball) and ran rubber to the ground for the first time! The steering angle is a bit lack luster so I might try and trim off most of the limiter tabs that everyone else talks about. 

[Rally! 142]

1 hour ago, An_RC_Guy said:

Anyways, I decided that I was not going to snap another ball stud and mess things up, so I bought a thread tapping bit at the hardware store. Just for everyone's knowledge the tap is a 3mm-0.50 for the ball studs and it also appears to be the same for the turnbuckle threads. Once the plastic was tapped the ball stud went right in with no issues.

 

That's great news. I'm going to see if I can find the same set here. 

[An_RC_Guy 90]

Hi everyone, wishing everyone a Happy New Year! Update on the kit, I got all the electronics in and the wiring nicely packaged. Next step is to cut out the body using my good ol steady hand with an xacto blade and the score and snap method.

[Rally! 142]

Looks great. Happy New Year.