Driving the Tamiya Wolf WR1, or is it a F104 now?

Getting pictures while driving, is hard.  But what I do have, are some stories.  And at least one pretty picture:

I ordered a bunch of parts to let me do some tuining on the F104w.  Only a few of them fit.  Here's what I can can say about parts for the F104w:  They're difficult to interpret, and hard to find.  The F103 spring kit fits.

The most useful information, is that the Tamiya Mini CVD's will fit in place of the stock support spring, and do provide some damping for the back end of the car.

So, onto the driving experience.  After completing the build, I was quite disapointed in how it was to drive the F104w.  It was fast, but any braking input caused it to spin, and acceleration was a exercise in patiance.  It has enough power to make driving on pavement a moderately scary experience.

Then again, it is a F1 car.



I didn't remember things being so touchy with my Bolink 91 sport.

Following the directions in the manual for setting up on a loose surface, things really didn't get much better.  In my order of hop-up parts, I also ordered some of tamiya's modern F1 tires.  They're a bit smaller in diamter, and much smaller in width.  They also have much rounder carcasses.

After putting the modern tires on the car, the cars behavior was much more predictable.  At the same time I also loosened up the ball diff a lot.  I keep getting stuck in the mindset that ball diffs should never slip, and should be setup very stiffly.  That's just not the case for pan cars.

The F104w also came with me to the track this weekend.  On CRC black carpet, and some STX tire sauce, the car was much, much better to drive around.  Left and right turning were mostly equal, it didn't spin on acceleration or braking, and it just wanted to go fast.

There was some axle hopping when in long corners though.  I think the foam inserts for the "classic" rear tires aren't stiff enough, and there may be some chassis tuning to do to help settle that down.  Or, I can just convert it to a F104 "normal" car, instead of a F104w.  That's, not as big of a deal as it might sound.

Cutting out the body wasn't as hard as the Wolf WR1.  The job took a couple hours, between decals, waiting for layers of paint to dry, and discovering everything that makes a F104w.. a W.

To convert from a "w" to a normal car, you need the F104 front suspension, "modern" f1 body, and a set of tires.

I also picked up another WR1 body.  Because I did the last one in metallic black.  And it's supposed to be painted in a special edition dark blue.  

 There will be pictures later, but I can't say I'm pleased with how tamiya handled the Wolf WR1 paint, and body.

Back to the subject at hand though.  The F104w is much happier on carpet.  Figuring out how to make it a good pavement car is still going to be a lot of work.  I've been told that switching to better tires makes a world of difference, so that's next up.

Till next time...  

Tamiya Wolf WR1 kit. A f104w chassis car.

Man, that looks like it means business.  

I've not owned a pan car since 1997 or so.  I've been itching to own one, and all of the dedicated pan pan cars out there tend to be pretty expensive.  Spending $300 on a pan car doesn't feel so hot when $300 will get you most of a 4wd buggy.

I was cruising Rctech.net, and someone in the F103 thread mentioned that the Wolf WR1, was for sale for a stupidly low price.  I suspect that means it's about to be discontinued, but that also means, I'm buying one.  Uh.. two. Yeah, I bought two.

A Little History
Tamiya has been making F1 r/c cars almost from the begining.  Their first F1 chassis was released in 1978.  And was a litteral pan car.  An aluminum pan, with foam tires, a metal direct drive rear axle, and suspension-less kingpins up front.

RJ Speed sells a car with "similar" configuration today.  The Digger, and Legends chassis.  But that's another story.

The "F100" series cars had their birth in 1986 as the Road Wizard.  That car lead to the car that eventually earned the name F101.  That car contributed greatly to the parking lot racing boom.  The F100 series cars were never "entry level" cars, but also were not aimed at serious racers, at least at first.

As pan cars evolved, with springs to carry most of the chassis weight, and then damper pads.  The F102 was an evolution of the F101, with better chassis stiffness, and fittings for damper pads.

The F103 was more or less a new car.  The front end mounts changed, the car switched to a complete two deck chassis.  It had a strut type front suspension.  And it came, even in the lowest spec, with a spring and a damper pad.  The F103 was the last F1 car from Tamiya to have transverse battery mounting.

This brings us to the F104.  It shares a lot of parts with the F103.  The front suspensions, the rear axles, things like damper pads are all about the same.  And, from what I've read, their road performance is pretty similar.

Tamiya didn't stop development there, and TRF took over the F1 car development.  Which, if I get there, will be the subject of it's own article.  Much like the high end touring car market, the high end F1 car market all really converged on one design, and it's hard to really make sharp distinctions about the different cars.

About the F104w
The F104w is one of Tamiya's attempts at taking a platform they already build, and make a scale chassis of it.  In this case, the "w" is a wider setup, to accommodate the older style F1 bodies.  In the process, the front suspension changed quite a bit, and you lose the aerodynamic front wing.  In trade, you get awesome bodies, like the WR1, Lotus 79, and other famous aero era F1 cars.

The high points:

• Fiberglass top and bottom decks
• Tamiya Hard Plastic everywhere
• Centered steering servo
• Longitudinal battery mount
• Easy radio tray layout
• A fully floating damper pad assembly
• Highly detailed body
• Many bearings in the rear axle.
• One piece thrust bearing!
• Ball Diff
• Rear load carrying spring

The low points:

• The rear pod is tight, making motor installation tricky.
• The battery pocket really only accepts roundside packs.
• Sliding kingpin front suspension (on the 104w...)
• No rear spring damper.
• Removing the right rear wheel resets the ball diff setting.
• The body is very challenging to assemble properly
• You need glues that aren't mentioned on the box.  CA, and rubber cement.

Photographing black parts, on black parts, nets you a black image.  ... go figure.

Criticism of the F104w

The car itself, I don't have much to speak about.  The radio trays are a bit flexible, and need to pivot on the top deck mounts.

The battery mount, while good for performance, is not good for ease of use.  It requires two body pins, and won't fit rectangular batteries.  To get my "square-ish" battery to fit, I had to put the friction o-rings for the radio trays under the trays instead of on top, to provide clearance for the round edges of the battery pack.

There's only one way to get battery leads out the top of the battery tray.  And that's essentially under the damper pad.

Building the Wolf WR1 F104w

I've built "one" real pan car in my life.  That was a bolink 91 sport.  There are other, similar cars, technically, my Kyosho Mini-Z's, and even my Tomy BitChar-G's were all "pan cars".  I even had load springs, a ball diff, and a range of t-bars for my Mini-Zs.  

But this was something interesting in it's own right.



Pan cars are really quite simple beasts.  It's just a stack of parts that starts at the pan and goes up from there.  The parts can look rather generic, so identification can be a problem.

For example, I put the damper pad springs under the kingpins when I first assembled my car.  You get two sets of small coil springs... the gold ones go under the kingpins, not the silver ones!

The chassis was a relaxing build, right until it came time to fit the battery.  Buy a roundcell LiPo, or else know that your battery is going to be a permanent installation into the chassis.

Tamiya is known for their bodies.  This one is no exception.  The Wolf WR1 body is quite the build.  The Wolf WR1 needs a special edition paint.  "PS Dark Blue"  That paint is available from Horizon Hobby at this time.  I didn't have the paint available to me, so I painted mine metallic black.  At a distance i'm not sure you can tell the difference, other than mine sparkles a bit.  It also saved me having to do some masking on the body.

Cutting out the body is a finger destroying project, the swingarm holes are tough, as are the creases behind the front wing, and the places where the body swings in to cover the rear pod.  I'd recommend drilling small holes at each inside corner, so the body doesn't tear at those locations.

The body, if you include the helmet, is seven peices, if you don't include fasteners, or things you can't see.



More black on black photography.  I need to do something about photographing these things.  More lighting would help to.  The body in black really made the car look good.

I found that doing the decals on the chassis was harder than doing it with just the body.  That's the opposite I found with the other bodies I've done.  Having the chassis frame of reference usually helps.

I still haven't painted the driver figure, but seeing the decaled body on the car for the first time, was shocking.  The car came alive.



Each rear view mirror, is it's own piece, stuck on from the inside.  The cockpit cutout is not a simple shape, to accommodate those mirrors, and the drivers  head.  The rear wing, is four pieces, three of which require painting.

The driver is three visible pieces, six if you count everything.  But adding the driver really finishes the look.  Sometime, i'll paint the drivers body, but for now, he's a clear ghostly body holding up a helmet.

So how about yours?
I have a Blue SR300 reciever, some generic brushed ESC, a Turnigy 4000mah 2s pack, and ~nothing else" on the car.  In the mail, I have an oil filled shock, a few t-bars, Tamiya's tuning spring set, fiber reinforced front suspension, bearings, and a spare body and tire set.



Sadly, I've not gotten to run the car yet.  There's been a lot of life going on....  But there will be a followup when that happens.  And when the hop up parts come.

Until next time....  

Just some pictures of my rc cars.

This is my TC4 wearing an non approved Barracuda body.

M workbench is rarely organized at the track.  But most of the cars are there.  The DT-02 is under the TT-02b body on the top left, the TT-02b is on top of the rail...

The TC4 wearing my practice body.  

The TT-02b just before it's first run.

Another shot of the TT-02b

My M05 ready for some street action.

The body on the M-05 is really very beat.

This is my DT-02.  It's a fun basher buggy.

The insides of my DT-02.

An Audi Quattro body on the M05.  Metallic silver doesn't play nice with the light dry coats method... so it's not pretty.

This is the special grease that Team Associated sells as green slime.  

The M05, before I screwed it up by driving it.

The ultra mini CVA shocks for my M05

I have a spare body, that will get painted like this.

First night at the track.

The TC4's initial build.  

DT-02 - Tamiya's do everything 2wd buggy

So lets talk about the DT-02.  

It's got all the features of a fancy buggy, at a hilariously low cost.  For reference, I bought one of the midrange models, for $110.  

A Little History

First, lets talk a little history.  In the early 1980's, Tamiya started releasing "cheaper" off road kits.  Tamiya had sold off road cars before, but they were high end products for them.  First came the Frog, in 1983, and in 1984, everyone's favorites, the Grasshopper and Hornet.  

This was just the start of a long list of cheap, versatile chassis that Tamiya would sell.  

Jumping forward a decade, Tamiya began the DT series buggies.  The 1996 release of the DT-01 was more or less, a Hornet, with decent shocks.  Still live axle in the back, still swing arms up front.  A transverse mounted battery.  The DT-01 was a kit dancing on the edge of Tyco, Nikko, and other toy store brands.  But, we're not here to discuss the merits of a fancy Grasshopper are we?  

In 2005 Tamiya released the DT-02.  https://tamiyabase.com/index.php?option=com_joodb&view=article&id=104&joobase=21&Itemid=1063  The chassis was set to bring back at least one classic car from Tamiya's history.  The holiday buggy.  As well as provide a platform for other hard shell, and polycarbonate bodied cars.  

About the Buggy

In comparison to Tamiya's other buggy designs, it was a very modern design.  Four wheel independent suspension, with a-arms and upper links.  The steering setup is classic Tamiya off-road. (for better or worse...)  And the gearbox is just about what you'd expect from Tamiya.  That is, nylon gears, sealed, and .6 metric pitch.  

The high points:

• Plastic Tub Chassis
• Sealed Gearbox
• Crud Proof Steering
• 4 Wheel Independent Suspension
• Durable Tamiya ABS plastic
• Reasonable Upgrade Path
• Easy Battery Management
• Just One Bearing Size
• Dirt Cheap
• Includes a Motor
• Sealed Power Switch

The low points:

• Most models come with friction dampers
• Limited Gearing Options
• No Slipper Clutch
• Soft Front Shock Tower
• Designed for Stick Packs
• A Bad Case of Bump Steer

Criticism of the DT-02

One of these days, Tamiya will start building their kits without bumpsteer in them.  But 2005, was not that day.  Between the unequal length steering links, and the absence of a rack to get pivot points in line, there's really not a whole lot that can be done.  

Access to the steering servo, for replacement or maintenance, is a bit troublesome.  It's a six screw job to get in there.  And being trapped under the chassis brace also limits the choice of servo saver.  

The chassis tub, and battery retention strap are really, very specifically, designed for stick packs.  With a little trimming you can get hardcase lipos to fit.  But it's not an ideal situation.  

Due to the motor surround, and gearbox design, getting wide gearing options is more or less a non-starter.  The gear cover holds one end of the spur gear shaft, this prevents easy changes of spur gear.  

Building the DT-02

First, this is now departing into "my experience" with the DT-02.

Building the DT-02 is typical Tamiya.  That's high praise.  The manual is good, and is specific to the version of the DT-02 you buy.  (I bought a Desert Gator)  And if you follow the directions, it all comes out perfectly.  

Be sure to have a JIS screwdriver, as that helps with the initial threading of screws into plastic.  A decent set of needle nose pliers will help assembling the CVD shocks if you got one of the ~better~ models.

Not counting the body, it took me about 3 hours to go from "pile-o-Tamiya parts" to "complete DT-02."

Painting the body was easy.  It's not easy to cut out, but the paint job is certainly easier than doing the paint on my Miata body for the M05.

Just a few words of advice.  First, pearl white, is not a solid coat, and needs a backing white paint.  Second, be sure to let your coats dry, and use very thin coats when painting over an existing coat.  

The decal job, is big.  But covers up most sins.  

The wings are usually molded "inside out."  so you need to do all the masking instead of trusting the build in overspray mask.  

All done, it looks a bit like this.  

It's a good looking buggy.  At least the desert gator is.  The Holiday Buggy, and other hard body buggys look pretty good too.  But are a good bit heavier.  I bought this for running on the local off road track while my on road batteries are charging.  

So how about yours?

I bought a Desert Gator.  Which is about the same as the Sand Viper, minus the speed control.  As opposed to something like the Super Fighter G, which has bushings, and friction dampers, it's got CVA shocks and bearings throughout.  

Sadly, the bearings are "just" shielded, as opposed to sealed.  But it's definitely something.  

So instead of going to the track I've been jumping off of things.  It handles stairs happily.  It jumps well.  On high traction surfaces, it will even wheelie!  

With the stock motor, it's slow enough that it handles being run into things very well.  It's also fast enough to impress people.  (if not someone who's really into r/c...)

When I bought mine, I also bought one for a friend of mine.  We built ours slightly differently.  

My car is built light.  I have a Turnigy D-Spec shorty steering servo.  A 2600mah 90c, ultra shorty battery pack, and team blue spektrum receiver.  It's very light, to get the correct ride height I only need about 3mm of preload.  

The other buggy, is set up with a standard size steering servo, and a compact 4600mah battery pack.  It needed almost twice as much preload to get the ride height proper.

Both cars are a blast to drive.  But there are some things were both looking to improve.  

What needs fixing.

With many low end cars, it's tempting to go nuts "fixing" everything on the car.  Eventually you end up deep into a car, where you could have just spent the same money and bought something better right off the bat.  

Realistically, this is why I bought the Desert Gator, as opposed to a Super Fighter.  Adjustable upper links, Bearings, and CVA shocks is a lot of value.  

The car could really use a ball diff.  Or sealing the gear diff, and filling it with something really goopy.  

A brace between the front shock towers should help the cars tendency to bounce the front end over ridges.  

There is some room to run bigger pinions, but you'll need to enlarge the motor mounting holes.  

How can I buy a DT-02, whats the best to buy?

The list is long.  https://tamiyabase.com/index.php?option=com_joodb&view=article&id=104&joobase=21&Itemid=1063#models-with-dt-02-chassis

• 93031 Super Fighter G Black edition
• 58340 Super Fighter G
• 58344 Desert Gator
• 58374 Sand-Viper
• 58401 Neo Falcon
• 58470 Holiday Buggy 2010
• 58485 Super Fighter GR
• 84212 Holiday Buggy (2010) Red version
• 58500 Sand Rover 2011
• 58522 Street Rover
• 58511 Nissan Titan
• 58536 Super Fighter GR (Violet Racer)
• 58553 Fighter Buggy SV
• 58615 RC Buggy Kumamonbajon
• 49475 DT-02 MS

If it were still in production, the "car to have" would be the DT-02 MS.  Sadly, it's long past it's production run.  Today, the car to buy is the Sand-Viper.  It comes with bearnigs, CVA shocks, adjustable upper suspension links, and an ESC.  (one that supports brushless motors too!)

The cars start at $100.  They're a lot of car for $100.

So lets talk about Batteries. Vol 1.

So let’s talk about batteries.

Many things about batteries depend on each other. Most people flying race quads are going to be flying 1300-1800mah 3 or 4s battery packs. I’m going to assume you know what mah are, and what 3s and 4s mean.

Chemistry is what really limits our batteries. Reaction area, and speed of the atoms and molecules. Reaction area, for LiPo’s works out to “physical size”. Speed of atoms is “literally” the definition of temperature. The warmer something is, the faster that reaction can happen.

LiPo batteries are built of thin layers deposited on big sheets of polyester. (I think it’s polyester) Some Lithium, Some carbon, a membrane that’s impregnated with an electrolyte. Those sheets get rolled up or folded up into the shapes we’re accustomed to seeing. If you’ve ever seen a bunt up battery, you can see those layers peeled apart. Durable batteries have thicker layers. Durable batteries have higher C ratings. We’ll come back to C ratings in a few moments. Batteries with more capacity, have bigger sheets of battery. These directly relate to the size of a battery pack.

For my 9xr ratio, I had a 2c 2200mah 3s pack, that was smaller than 1500mah 20c 3s pack. A 45c 1500mah 3s pack, is about the same size as a 2200mah 20c pack. This is due to the tradeoff of cell area, and cell durability. “Stronger cells” are thicker.

Now we need to talk about abuse. And abuse is something that we do ~very well~ in the multirotor community. Tiny batteries, steep pitch, and multi blade props, four 20-30-40 amp ESCs and 2000kv+ motors. (High Kv essentially means “low turn” for the r/c car guys.)

Battery packs beyond their capacity and number of cells, are rated on the “C” rating. C is “the capacity of the battery” The “C” rating is a multiplier of the capacity of the battery. This lets you do some math to figure out how to treat, and what is considered abuse of the battery. There’s going to be a separate charge rating for both charge, and discharge. Typical limits for charging are in the 2-4C range. That’s 2-4 times the capacity of the battery.

For instance, if we have a 1300mah battery pack, we could safely charge it at 2.6 to 5.2 amps. Slower charging is always better for a battery. To a limit… I don’t have any research handy, so I’ll say you don’t want to charge LiPo at less than 1/10C. This relates back to our bag of chemicals, the slower we charge, the more time atoms have to do their thing. The slower we ~need~ them to move, the less likely they are to damage their surroundings. If you exceed the speed that those chemicals can react, ~things~ start happening. For instance, electrolysis.

Electrolysis is the splitting of chemicals via electricity. Generally, it’s water, and that’s how we get puffed packs. When you push a pack to hard, and you get water splitting into H2, and the O2 then oxidizing other parts of the pack, you end up with a puffy pack, and less reaction area due to oxidation.

Let's stick to abuse. Charging, or discharging quickly, causes heating. Moderate heat can be a good thing. Batteries can “have things done to them” faster, if they’re warmer. To a limit, either by generating vapors, or, let's say, fire.

When charging, or more importantly, discharging, heating comes from within the pack itself. While we’re used to the idea of batteries providing power, they also consume some power. All parts of an electrical circuit, have some resistance. That includes LiPo batteries. This resistance is called “internal resistance”. For LiPo batteries used in commercial situations, which frequently see ~very~ cold temperatures, the procedure for starting involves a two step process. First, is “knowing” the cart/truck/plane won’t start, and applying the starter for a few seconds. This puts a high load on the battery, warming the pack. Then, you wait a few seconds, and try again. The engine would start on the second attempt, because the warmer battery could provide more current without the voltage sagging under load. Some r/c car people have taken to preheating their LiPo packs with some very high C charging. We’ll come back to voltage sag.

Now i’m making it sound like batteries being warm, is good. Unless you’re having peak current issues, it isn’t. Batteries age in relation to their temperature. The warmer they are, they faster they lose capacity and C rating. It’s better to keep batteries cool. Cold even. But not frozen, as that can cause the electrolyte to freeze and directly damage the cells from the inside.

In the past, the internal resistance of batteries were there to save us. You could short out most NiCad, or NiMh batteries and nothing would happen. They’d get warm, and finish discharging. No ~real~ drama, excepting some of the very latest NiMh cells, funny, that was discovered by the r/c car guys too. Maybe we should stay away from r/c car people. Do the same with LeadAcid, and you might get some steam… Their discharge would be self limited by chemistry and internal resistance. This, is not the case with LiPo. The internal resistance of LiPo packs are often in the miliohm range. This means we need to do current limiting somewhere else. Sometimes we don’t….

And when we don’t, because a lot of us use OSD’s, we’re aware of “voltage sag”. Voltage sag is what happens when we get ahead of the chemical reactions that restore the voltage of our batteries. Voltage matters to us, because our motors are a long series of wire coils. And the speed at which we can energize those coils, is directly related to the available voltage.

Back to cell abuse, deep discharge of LiPo batteries is a problem. When the voltage is ~very low~ in a LiPo cell, some of the copper used in the battery can dissolve in the electrolyte. This makes it more conductive, and makes it more prone to runaway. It’s also irreversible.

So how do we stop our packs from dieing? Keep them somewhat charged, so they don’t dissolve into themselves. Keeping a battery charged also has it’s downsides, when you charge a battery, you’re forcing the battery into a state it does NOT like being in. That is, it holding the positive and negative poles as far apart, electrically, as it can. So the lower voltage you can store it at, the better. But batteries also self discharge, so you need to have “some” buffer. The generally accepted voltage is 3.6v, for storage. Finally keep them cool when stored. Higher temperatures increase self discharge rate, and the damage the cells do to themselves while stored.

I ~think~ I have all of that right. I didn't cover balancing or cell choice. But that gets into an even longer discussion.

A little more Doink(er)

I made some more progress on the Doinker.  In fact, short of the props, it's complete.

There were a few steps leading up to that though.  I had to populate the PicoBlox.  The first thing I added was the power stub for the camera.



I really didn't get any pictures of modifying the receiver tray, and the spektrum satellite.  It's stuffed under the flight controller.  I have thick spacers under the FC to provide clearance for the satellite wire.

It's not the most pretty solution, but the "wedge them in" ESC mounts is quite elegant.

16ga wire is a little big.  Here I'm trying to get the receiver bound.  

Happily, I only got one motor wired backwards.  That's a first.  I've had as many as three of four spinning the wrong way.  The wires on the 1104 motors have varnish on them, so when you shorten, and strip them to attach to the ESCs, sand the wires a little, or else your flux and solder just ball up and fall off.

In the end, I swapped the 16ga lead for 20ga going to a JST plug.  Most of my multi cell lipos are either e-flite 3pin, or T-connector.  So I built two adapters to I can use all three kinds of battery without any real strain.

Next is to order a few batteries, and cut down some props.  

Adding FPV to a normal Micro Radian

E-Flite released a UMX Radian with a FPV camera on it.  I thought this was a great idea, but I really didn't like the idea of spending $99 on top of the cost of the glider for a $40 camera and a $7 mount.  

So the first step to adding FPV to a micro plane, is to get power for the camera.  That means cracking open your bird.  The canopy is held on with "just" tape.  The tape to use for putting it back together is Scotch brand 1/2" clear tape.  The glossy stuff.

The UMX radian has a additional speed control board.  There's three pins that feed it, and my pencil is pointing at it.  

The center pin is battery positive, and the pin nearest the sockets is ground.

I bought a bunch of eflite mini JST plug extension wires.  So I cut one in half and slipped it through the canopy.  To put a hole in the canopy, use a normal 3/32" drill bit and spin it in your fingers.

I taped the wires to the inside of the canopy.  Then I soldered the wires to the reciever.

And there we go, a plug on the top of my glider to power a FPV camera.  The factory FPV camera mount is $7 from E-Flite.  Or you can just hotglue your camera on.