TT-02 SSS... Stock Build. Almost.

[skom25 2321]

Hi,

Sometime ago, I found that I prefer to run On Road, instead of Off Road.

During winter I built XV-01. As always, something went wrong and I spent bag of money on Hop Ups.

I sold DT-03 and decided to just buy "Happy" On Road basher, have fun and do not care. You know how it is with expensive cars. You want to have fun, but at the same time you are worried to not break it etc.

I found, I believe, excellent offer. Limited edition TT-02 with Painted CLK body for 90 Euros.

BTW. Is this rare body? I have not seen it before.

Plan is simple: build it stock, only with small low cost modifications, mainly from parts I already have.

I already bought Ball Bearings, Rod Ends to install adjustable turnbuckles in steering and spare A parts, because I have great skills to do Uprights in a wrong way.

I already have:

- Super Stock BZ motor. I can use it in Touring Car, right?

- King Pins for steering

- Some Ball Connectors

- HT Servo Saver

- Aluminium Hexes

- Stainless machine Hex screws

 

What I want to buy?

- Definitely CVA shocks

- Aluminium suspension balls

 

Should I consider anything more? Any Tips and Tricks?

I know TT-02 chassis quite well, but B version.

[Kowalski86 4484]

2 hours ago, skom25 said:

Should I consider anything more? Any Tips and Tricks?

I know TT-02 chassis quite well, but B version.

Nope, just build it as is and drive it until you wear the tires out. Just get a steel/coated pinion suited to whatever gear ratio that you want.

I think that even the HT servo saver is overkill, lately I've been creating my own plastic horns for my on-road Tamiyas.

What I'll do is take one of the "X" crosses that come with a servo, cut the ends off to make a horn, and tap the hole at the end to accept a screw or ball joint. Works fine and it costs nothing. Plus, it's not like you're going to ruin the servo with the wheels tucked in and a giant foam bumper up front.

The plastic driveshaft/cups are robust for what they are, people have run brushless systems through it without trouble. They flex in a crash vs bending.

If you want an easier time pulling out of turns, put some AW grease, earplugs, chewing gum, packing foam, whatever in the front diff (I've tried all of these), stiffen the back if you like drifting.

[skom25 2321]

• What about central shaft? Should I think about aluminium if I want to use Super Stock motor?
• I already have HT Servo Saver, so will just use it. If not, I bought some cheap stiff horn. Maybe it is good moment to use it.
• I have plenty of AW grease, so plan is to use it a lot in front diff and minimal amount on rear or even standard grease.
• In spares, I have new, steel 19T pinion but I believe it is too small with gear ratio around 9.5.

 

[Kowalski86 4484]

14 minutes ago, skom25 said:

• What about central shaft? Should I think about aluminium if I want to use Super Stock motor?
• I already have HT Servo Saver, so will just use it. If not, I bought some cheap stiff horn. Maybe it is good moment to use it.
• I have plenty of AW grease, so plan is to use it a lot in front diff and minimal amount on rear or even standard grease.
• In spares, I have new, steel 19T pinion but I believe it is too small with gear ratio around 9.5.

 

1. The plastic one is fine, but with how cheap an aluminum shaft is it wouldn't hurt to run one. Don't bother getting aluminum cups though, they give better precision but they wear sooner.

2. Either the horn or HT servo saver will be fine.

4. I'm not sure how to correctly gear for a Superstock motor. The stock pinion is 22t. 

If you really want to play with gearing, the high speed gear set hop up isn't a bad buy. But you'll loose a bit of punch with the 64t spur gear.

[Pylon80 4037]

The TZ/BZ makes for a really hot TT-02. Mine was geared 70/17 and car felt really fast, noticeably faster than with the Sport Tuned. I then tried 70/16, more because the motor was getting so hot with 17t. That did not change anything in terms of motor temp. The car was feeling like it was topping off on the straight, basically geared too low. So I went back to 17t which would be my recommendation for a really nice car.

 

[skom25 2321]

17 minutes ago, Kowalski86 said:

I'm not sure how to correctly gear for a Superstock motor. The stock pinion is 22t. 

Gearing for BZ is from 9.1 to 11. However, it is range for Buggies. Super Stock RZ is for 8.5 and lower. I have feeling, that with 19T pinion it will accelerate like a rocket, but Top Speed will be very limited. 

I have some time to think about this, because motor will be last thing which I will install.

19 minutes ago, Kowalski86 said:

If you really want to play with gearing, the high speed gear set hop up isn't a bad buy. But you'll loose a bit of punch with the 64t spur gear.

Set includes 68T Spur. As I said, I do not want spend money on this kit, so will stay with with stock version, especially that I have barely used spare from TT-02B.

One question more:

Should I go for Low or High version? What is clearance in both?

 

[Kowalski86 4484]

45 minutes ago, skom25 said:

 

Set includes 68T Spur. As I said, I do not want spend money on this kit, so will stay with with stock version, especially that I have barely used spare from TT-02B.

One question more:

Should I go for Low or High version? What is clearance in both?

Yea, the stock 70t spur is perfectly fine for just driving around the street.

"Rally mode" gives you a few more mm, however the bottom of the wheel hubs will stick out quite a bit. If you're just running on flat ground the low setups fine.

[skom25 2321]

49 minutes ago, Pylon80 said:

The TZ/BZ makes for a really hot TT-02. Mine was geared 70/17 and car felt really fast, noticeably faster than with the Sport Tuned. I then tried 70/16, more because the motor was getting so hot with 17t. That did not change anything in terms of motor temp. The car was feeling like it was topping off on the straight, basically geared too low. So I went back to 17t which would be my recommendation for a really nice car.

 

Currently in TT-02B I have 17T and it feels quite fine. Buggy wheels are much bigger and I do not feel that it has problem to reach max revs. I am bit surprised to be honest, especially that stock Pinion is 22T.

[skom25 2321]

First technical question:

MB2 screw. Why it is different than others? Is there any reason?

I want to use machine Hex screws and really wonder, why it is not the same as rest of kit screws.

[DaveBuildsRC 219]

3 hours ago, skom25 said:

First technical question:

MB2 screw. Why it is different than others? Is there any reason?

I want to use machine Hex screws and really wonder, why it is not the same as rest of kit screws.

should be ok to use a machine screw and washer there.

[Kowalski86 4484]

Will you be tapping the holes before using machine screws? Just screwing in machine screws on their own is hard on ABS plastic.

[skom25 2321]

6 hours ago, Kowalski86 said:

Will you be tapping the holes before using machine screws? Just screwing in machine screws on their own is hard on ABS plastic.

Yes!

Tapping is like next level in quality. I did this in XV-01 and even decided to rebuild TT-02B with new parts, just to have machine screws. 

[skom25 2321]

First step and... first fail.

I was shocked. I cannot say anything more.

I tapped whole XV-01, TT-02B CF chassis and some parts for DT-03. I did this in the same way, but it seems that TT-02 Standard chassis is bit different that rest of the parts I have done. However, I found also interesting fact about TT-02 chassis.

Issue:

Right from the start, I found that there is quite strange white powder on thread after tapping. It was also on tool.

It was not an big issue till...

... this happened. Plastic turned white on the side of the hole and about 3/4 of thread is gone. Heat? I am not sure. I did this very slow.

Ha! No problem, because I have spare chassis!

I decided to try tapping with grease, which helped a lot but then I found that:

Kit chassis:

Spare chassis:

They are not the same! There is no bulk on that place.

As you can see, even when I used grease, there is a white mark on side. I believe wall is too thin and they just updated chassis.

What I found, that spare chassis without bulk, has a lot more dents where plastic shrank after release from mould. It is just... worse.

How to recognize old vs new/ updated chassis?

Old:

 

A912784-01

ABS and ABS-CF version only

Updated:

A912784-02

ABS, ABS-GF and ABS-CF versions.

It is strange, because I bought this spare chassis less than year ago. Stock TT-02B was "updated", as well as CF version and chassis from current kit. In that case, there are two options:

1. Both versions are produced at the same time

2. I bought chassis which was in a storage for a looong time.

Despite I have that spare chassis, I decided to order new and this one leave as a ready spare. Why?

1. Maybe I will get this updated version, which is better

2. Some time ago I tapped holes for diff covers without grease, so they are not good as I expect to be.

3. I have not seen this when I bought it, but there is small cut on the edge. It is just visual defect.

Summarizing, chassis is functional, but at the same time it is so cheap, that I prefer to use new one.

Chassis probably will be delivered tomorrow, so today I will try to build diffs.

[one_hit 1127]

@skom25 the chassis that came with your kit was manufactured July 2016 while your spare chassis was manufactured on July 2023. The older chassis is probably already degrading and becoming brittle. The stock TT-02 tub is so soft that you really don’t need to use a tap even if using machine screws. Just some grease on the screws will do.

[skom25 2321]

@one_hit probably I will mix both methods.

Tap thread for about 3-5mm to have starting point and then just use screw during assembly. Of course, I think about chassis. 

In smaller elements it is much easier to tap whole thread and do not risk that something will go wrong.

[skom25 2321]

12 minutes ago, one_hit said:

@skom25 the chassis that came with your kit was manufactured July 2016 while your spare chassis was manufactured on July 2023. The older chassis is probably already degrading and becoming brittle. The stock TT-02 tub is so soft that you really don’t need to use a tap even if using machine screws. Just some grease on the screws will do.

No. Spare chassis in "old" specification is from 2016. New, from kit is 2023.

[one_hit 1127]

1 hour ago, skom25 said:

No. Spare chassis in "old" specification is from 2016. New, from kit is 2023.

You’re right, I mixed them up. That’s interesting about the added bulk on the chassis. I’ll go check my spare chassis, I bought around 3 or 4 of the CF reinforced lower decks last year

[Exvee-Ohwan 105]

Curiosity got the better of me and I had to go and check mine, I also have the updated 02 revision part in my Audi V8 kit.

The molds for producing these parts are hugely expensive, I guess Tamiya produced an updated 02 mold for the new part but will continue to use the existing mold and churn out the 01 part in parallel.

[Pylon80 4037]

Very interesting, I didn't know Tamiya had updated the lower deck. For what it is worth, I once ruined a reinforced lower deck by tapping holes without grease. Since then I use grease and never had a problem. I tap every hole over the full depth and never use a screw directly to butcher the threads in. This makes for some very durable and accurate threads that let you hear the 'click' every time when turning ccw on reassembly.

[skom25 2321]

Update:

Yesterday I built diffs. Front one with A LOT of AW Grease. It feels really stiff. Rear with good amount of grease, but still loose.

Internal gears was sanded a bit, to remove all sharp edges etc. After assembly, I put diffs into chassis, rotated and tried to find uneven places on cover. It is long and boring process. You have to screw/ unscrew each of four screws just a bit and check once again. It is almost impossible to make them perfectly straight.

However, there are at least two reasons why you do not have to worry too much:

- Diffs are really cheap

- There is a lot of play in whole drivetrain, so there is no possibility that gears will be blocked

Then I prepared chassis. All holes are tapped. This time with grease. Chassis I received is in new, updated specification. Uff!

After chassis, I prepared first set of parts. 

Everything was washed, to remove that residue from moulds.

It is easy to buy fancy, blue parts and install them. More satysfying is to make stock parts better.

I installed it in drill and sanded plastic part. Now it is quite smooth and shiny. Then I polished metal axle. However, after I cleaned it in water, some strange stains appeared on polished area. 

As you can see on previous photo, I received few upgrades:

- 3x22 stainless shafts

- Low Friction suspension balls

- 3x18 Turnbuckles

- Stainless Hex screws

I have to say one thing:

I am impressed with TT-02! Now I understand why it is so popular.

I had experience only with TT-02B. To be honest, it is much, much worse. There is a lot of slope everywhere, plastic is very soft, almost like a rubber. Straight from the box, it is really dissapointing. 

Touring Car version is really great!

[Pylon80 4037]

The front diff will get almost completely loose after an hour of driving or so, once the AW grease has been centrifuged away from the gears. AW grease works good, but needs to be cleaned and re-applied all the time for consistent results. This is not a problem for most of us of course.

[skom25 2321]

Oh, that is interesting. I think it still will be much thicker than standard grease.

[Pylon80 4037]

Just now, skom25 said:

Oh, that is interesting. I think it still will be much thicker than standard grease.

I have stock diffs on my rally TT-02, standard grease and AW grease for the front and rear respectively (which is the opposite of what you would do for on-road). The difference was tremendous. After an hour of driving time you really couldn't tell which one was which when spinning the wheels by hand. It's ok; it just requires more maintenance to keep it the way you want.

That car is about to get two oil filled gear diffs... When I get around to it!

[Exvee-Ohwan 105]

3 hours ago, skom25 said:

After assembly, I put diffs into chassis, rotated and tried to find uneven places on cover. It is long and boring process. You have to screw/ unscrew each of four screws just a bit and check once again. It is almost impossible to make them perfectly straight.

Ah - I had this on my build.  There was some faint notchiness in the drive train which I isolated to the rear diff.  I did consider taking it out and redoing it, but as you say, there is so much built in slack in the drive train that it just doesn't really matter.  If a diff ever explodes it's a £4 part so not something I'm going to lose sleep over.  

[skom25 2321]

As long as it is not blocked or really tight, you do not have to worry about this. It feels bad when you rotate parts with hands, but with motor installed it is totally fine.