BBenny

DT03 Chassis / bumper

Recommended Posts

Why have Tamiya (and all RC makers) stopped putting decent bumpers on their cars?

I'm running a 1990 Thundershot with a lovely big bendy bumper. It helped the car survive some pretty bad treatment.

My boy (6) has the Neo Fighter DT03. Running stock, although with 2s lipo. He has just broken the second chassis, on the nose where the last one went (to be honest, that time was my fault). Of course the model is "only suitable for over 14y" but he's a decent driver already and it gets me a chance to play too.

I'm replacing the chassis, but wondering if there are any third party or 3D-printable bumpers out there that cover the front end better than the stock item?

Is there a good way to reinforce the front end of the chassis?

Thanks

Share this post


Link to post
Share on other sites

I think a lot of people criticised them for being too "toy like" I always thought they were an integral part of the overall look of them!

Share this post


Link to post
Share on other sites

There may be an aerodynamic explanation. A big, wide, kick- up front bumper is effectively a front wing, lifting the nose at speed. And being stuck out in front of the car, hitting clean air, It has a good chance of actually working too. Not really good for performance or handling.

Share this post


Link to post
Share on other sites
18 minutes ago, TurnipJF said:

Not really good for performance or handling. 

This is so true, the last thing it needs is to make the front even lighter! What about a wider one like a hotshot with its name cut into the form of it? Some of the air would at least travel through it..stopping it from being an aerofoil. I may be over thinking this however! 😂 

Share this post


Link to post
Share on other sites

I’ve found the alloy offerings that are a flashy copy of the stock bumper. Totally useless as far as I’m concerned. 

Agree that the hotshot bumper would be ideal. Disagree about aerodynamics though, I’d guess this is only relevant at far higher speeds than this little buggy can achieve.

The DT03 bumper also serves to keep the hinge pin in place, so a replacement would need a bit of design work.

Is anyone any good at CAD? 

Share this post


Link to post
Share on other sites

Have to tried the Thundershot bumper on the DT03, looking at picks on Google, it looks like a bit of a trim and some holes drilled, it would fit? 

Share this post


Link to post
Share on other sites

I think it's more of a look thing.  I think they can make a stylish bumper, though.  

But if I want to be cynical... broken parts mean more business... (at the expense of reputation)

 

Share this post


Link to post
Share on other sites
4 hours ago, BBenny said:

I’ve found the alloy offerings that are a flashy copy of the stock bumper. Totally useless as far as I’m concerned. 

Agree that the hotshot bumper would be ideal. Disagree about aerodynamics though, I’d guess this is only relevant at far higher speeds than this little buggy can achieve.

The DT03 bumper also serves to keep the hinge pin in place, so a replacement would need a bit of design work.

Is anyone any good at CAD? 

I did a big Grasshopper style bumper 3D printed for my DT03 but it was no good. 3D printed nylon is way more brittle than ABS moulded plastic. I snapped two super easily before giving up on them. 

  • Like 1

Share this post


Link to post
Share on other sites

As I remember, the original grasshopper bumper snapped pretty easily. My early 90s example has an aftermarket bumper which was far better.

a little off topic here, but has anyone tried fitting the grasshopper 380 motor to the dt03? I guess I’m a bit weird by wantin to go slower, not faster! But less mass and less speed = less broken stuff.

  • Like 1

Share this post


Link to post
Share on other sites

That is odd.  The Grasshopper bumper is next to impossible to snap. It's like half-rubber. I have a few vintage cars from the 80's.  Even after 30 years, they are all quite flexible.  The bars on both ends are bent up, and ground thin quite a bit, but still unbreakable.  Unless you hit a wall squarely on the square portion.  

Or... maybe you bought a bumper and that happened to be a clone bumper?  'Pintopower' often review clones of the Grasshopper on his youtube channel.  Maybe their bumpers were brittle, even though they look the same?  

 

  • Like 2

Share this post


Link to post
Share on other sites

Well, I was a kid at the time, and had obviously put the 540 and 7.2v battery in there...possibly even the Parma super stock.

 

  • Haha 1

Share this post


Link to post
Share on other sites
1 hour ago, Juggular said:

That is odd.  The Grasshopper bumper is next to impossible to snap. It's like half-rubber. I have a few vintage cars from the 80's.  Even after 30 years, they are all quite flexible.  The bars on both ends are bent up, and ground thin quite a bit, but still unbreakable.  Unless you hit a wall squarely on the square portion.  

Or... maybe you bought a bumper and that happened to be a clone bumper?  'Pintopower' often review clones of the Grasshopper on his youtube channel.  Maybe their bumpers were brittle, even though they look the same?  

 

Maybe a 3d printed mounting that screws to the 03 bumper mounts and has lugs for the GH bumper? That might be doable. The 3D printed part would be pretty solid.

Share this post


Link to post
Share on other sites
2 hours ago, BBenny said:

As I remember, the original grasshopper bumper snapped pretty easily. My early 90s example has an aftermarket bumper which was far better.

a little off topic here, but has anyone tried fitting the grasshopper 380 motor to the dt03? I guess I’m a bit weird by wantin to go slower, not faster! But less mass and less speed = less broken stuff.

Just get a 35t crawler motor. Way slower than 25t Torque Tuned supplied. HPI do one for under a tenner.

  • Like 1
  • Thanks 1

Share this post


Link to post
Share on other sites
4 hours ago, BBenny said:

A little off topic here, but has anyone tried fitting the grasshopper 380 motor to the dt03? I guess I’m a bit weird by wantin to go slower, not faster! But less mass and less speed = less broken stuff.

The DT-03 uses the same gearbox as the DT-02, some versions of which came with a 380 size motor, so I don't see why it wouldn't work.

Just get a DT-02 Holiday Buggy motor adapter and motor support (both on the H sprue, part number 19005989) and you should be good to go. 

  • Thanks 1

Share this post


Link to post
Share on other sites
On 10/3/2018 at 3:37 PM, TurnipJF said:

There may be an aerodynamic explanation. A big, wide, kick- up front bumper is effectively a front wing, lifting the nose at speed. And being stuck out in front of the car, hitting clean air, It has a good chance of actually working too. Not really good for performance or handling.

While you are right in what you say, in that a kick-up front bumper generates lift by forcing the air the car moves through downwards and underneath, in reality this will make virtually no difference at the speeds the car is likely to be achieving with a standard 540 and 2s Lipo, especially if it is being used on any sort of off-road surface. There was a a whole thread about aerodynamic effects on 1:10 off-road buggies on here a while back, and the ultimate conclusion was that aero had no effect at all below about 20mph, due to the fact that the frontal cross-section of a buggy is so cluttered and compromised that there is no clean airflow for it to work in. This came mainly from an interview with a Schumacher engineer who had actually researched the matter.

That said, there will be certain circumstances in which a big bumper like that would make a difference. Over on the 'Official Top 10 Fastest RCers' thread, @Andyrt200 has a Thundershot which he uses for speed runs and which can achieve over 57mph on a more-or-less flat surface. Given the speed and flatness of the terrain, the big kick-up bumper on that car may well be making the car nose-light, simply because of the sheer amount of air it is having to deflect downwards as it bombs along.

But at normal 540 speeds on anything but a billiard table-flat surface, @BBenny's car will be compromised in so many other ways that the aero effects of the bumper is going to be a long way down the list.

Share this post


Link to post
Share on other sites

You need a sprung bumper like the WR02 if you keep driving in to things. A DT01 one might bolt on with some work, they are big and robust.

Share this post


Link to post
Share on other sites

Haha my sons have broken 2 rear axles - (effectively looses the wheel as it snaps where the pin goes through) on my DT-03 and nothing on the front so far - I guess they go sideways faster than forwards ;) ...

And generally I use the EPA function when my younger son is playing which is a lot easier than changing the motor :) 

 

 

  • Thanks 1

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now