Tamiya TB Evo 6
#616
Grinding the hole for the smaller 10mm bearing cured the case rocking side to side? That seems odd to me, as my rock on their own with no bearings or anything inside. In fact, I think they rock on the edge opposite the input shaft, that is the edge I ground down in one of them to make them fit right. It's just difficult to tell what makes the gear diff (side) bearings bind when the case is screwed down.
#617
Tech Elite
iTrader: (36)
I agree about the fitment issues. I'll see what the Tamiya officials had to say about my cases (they made their way to TCS nationals ), but for now I'm just hoping Exotek or someone will have mercy on us and produce some blue anodized alternatives
#618
Tech Elite
iTrader: (22)
The case halfs straighten out when you tighten them together, don't they?
Seriously....I never checked that part for trueness. I just always put the parts in the lower case, and slowly tightened the screws in a crossing pattern. If both of them are bent, as long as they flush up.....the bearings are tight on installation. If they don't fit in with an interference fit, you will destroy the gears when they walk around on you.
I will check them again on the next one I build.
Seriously....I never checked that part for trueness. I just always put the parts in the lower case, and slowly tightened the screws in a crossing pattern. If both of them are bent, as long as they flush up.....the bearings are tight on installation. If they don't fit in with an interference fit, you will destroy the gears when they walk around on you.
I will check them again on the next one I build.
#619
Tech Addict
iTrader: (39)
Thanks guys for posting helpful tips on the solutions you have come up with, It has helped me get my cars alot smooth. I also put 6, 3mmx0.3mm shims between the two case halves so the top case doesn't squash the bearings as much made huge difference.
I'll post a picture soon
I'll post a picture soon
Last edited by E-clip; 08-26-2014 at 03:46 AM.
#620
Tech Elite
iTrader: (22)
There is no way smashing the steel bearings in a plastic case is going to bind the transmission. I remain confused by all of this.
Tonight, I will build the transmission out of my other EVO6 kit, and take pictures. I will attempt to replicate the problems other users are having.
They all are. You can fix that with some carefully applied heat from a heat gun, a dead flat surface, and a couple of C clamps. Heat up a piece of scrap Tamiya plastic till it melts so you can figure out what the "hot enough to start stinking but not melted yet smell" smells like. It it starts to blister, that's too hot.
Then, clamp it up and heat the chassis with the tweek to the "smell" point. You can unclamp it and bend with your hands if it's really bad.
Tonight, I will build the transmission out of my other EVO6 kit, and take pictures. I will attempt to replicate the problems other users are having.
They all are. You can fix that with some carefully applied heat from a heat gun, a dead flat surface, and a couple of C clamps. Heat up a piece of scrap Tamiya plastic till it melts so you can figure out what the "hot enough to start stinking but not melted yet smell" smells like. It it starts to blister, that's too hot.
Then, clamp it up and heat the chassis with the tweek to the "smell" point. You can unclamp it and bend with your hands if it's really bad.
#621
Tech Apprentice
As mentioned before the modification is very simple and maybe the original small 16T bevel gears will also be good enough. Use a 9 or 10 mm wood drill bit, drill approx 1.5 mm from the top of the 16T bevel gear ( small end ) to copy the indent that is in the TB-04 EVO 6 16T bevel gear so the c-clip will fit. I did it by hand and it took about 30 seconds to do.
The 39T bevel gear or TB EVO 5 One-Way gear is a direct fit.
Never had a problem driving 13.5 Boosted 12T(Tamiya) or even 6.5T with the Evo 5.
Andre
The 39T bevel gear or TB EVO 5 One-Way gear is a direct fit.
Never had a problem driving 13.5 Boosted 12T(Tamiya) or even 6.5T with the Evo 5.
Andre
#622
Tech Elite
iTrader: (36)
Keep in mind also that these plastic cases seem to vary greatly in quality control. Perhaps you got really nice ones?
#624
Tech Elite
iTrader: (36)
Haha, I'm not offended or angry man, but color me confused. I've spent HOURS with these cases, trying to identify what is preventing my bearings from free spinning, and it has to do with the pressure the case applies to the bearings when screwed together. Adding shims between the case halves actually improves the situation, but results in too much up/down movement in the bearings.
If you can prove me wrong, please, please do it! If you can guide me to a free spinning drive train I'll love you for ever
If you can prove me wrong, please, please do it! If you can guide me to a free spinning drive train I'll love you for ever
#626
Tech Elite
iTrader: (36)
I do wonder if the metal miter gears and/or the metal gears in my diffs add to that problem. More friction between the miter gears, more rotational weight with the heavier diffs.
#628
Tech Master
seeing how long a car spins for is not really that important, it doesnt really dictate that it will be better at accelerating or faster.
The most important thing is to ensure that its just free so that the force that is required to accelerate the car to its maximum velocity and to maintain it.
This is all down to the mass of the drivetrain, and the friction it has along it. A car that freewheels for a long time may have a heavier drive train than one that freewheels for less time, but assuming they are both free then the lighter drivetrain will be the better one.
Years ago I got obsessed with all of this, I had a TBevo3 that span for ages, but once I became clued up and swapped out to lighter components the car was much quicker on the track despite the wheels not spinning for as long.
As long as its not binding, and it moves on a slight incline I am more than happy with all of my cars nowaday (Belt and shaft)
The most important thing is to ensure that its just free so that the force that is required to accelerate the car to its maximum velocity and to maintain it.
This is all down to the mass of the drivetrain, and the friction it has along it. A car that freewheels for a long time may have a heavier drive train than one that freewheels for less time, but assuming they are both free then the lighter drivetrain will be the better one.
Years ago I got obsessed with all of this, I had a TBevo3 that span for ages, but once I became clued up and swapped out to lighter components the car was much quicker on the track despite the wheels not spinning for as long.
As long as its not binding, and it moves on a slight incline I am more than happy with all of my cars nowaday (Belt and shaft)
#629
Tech Master
iTrader: (4)
Join Date: Mar 2009
Location: Tween a Rock & a Hard Place in Pa.
Posts: 1,279
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Nice car but a lot of niggly bs for the price,hope it is really,really good for the amount of you have to do to it.