Oh well, another one of those weekends and off to Bashley for some boat racing. I mean Car racing if it is dry!. This time the Gazebo is water proof…. We think 
New Cyclone car, New Nosram 10.5 motor, New Futabe Servo, New 2.4ghz KO Esprit III system. What else can I change? Maybe the the driver if it all goes wrong.
We were not going to use our blog as a advertising point but thought I would for this, as loads of you have been asking when the Serpent S400 gear diffs would be back in stock. Guess what, they are. Finally. Thanks.
So decided to take a trip up to the Cotswold last Sunday. Woke up at 5 and headed off about 5:30. Got to the track and guess what, raining. However, we where proud of ourselves as we had got a nice new waterproof gazebo. Let’s see the British weather stop us now. So got it all setup in case the rain decided to stop and unpacked all our gear ready for (maybe) some racing. Anyway decided to take a stroll around, stopping at each tent and gazebo on the way around to minimize getting soaked. We had to laugh as we entered a gazebo which was leaking as it was not waterproof. What made it even funnier was the site of about 4 people inside with large umbrellas (which could barley fit) trying to hold back the rain. How proud we where that ours was water proof, chuckle chuckle……
The laughter was short lived. Decided to get back to our area, walked inside and.. WET WET WET. Leaking, waterproof my backside. Upon investigating further we discovered that it was water resistant. Oops not waterproof. Not even splash proof, as after about 10 minutes later we could have got the shampoo out.
So at around 9:30 the meeting gets called off as the heavens opened. Never mind, and we decided to pack up quick and see if we can get booked into Aldershot for the rest of the day as it was said to be dry. So 1 hour 30 minutes later, we almost arrive and the weather looks good. 5 minutes later and guess what, yep we brought the weather with us and the heavens opened again. Bl**dy typical!. At this point we decide that the British weather has beaten us and decide to get back for the Grand Prix, ultimately thinking that it would also be called off too. Not this time…
Unfortunately the day had Beaton me and I nodded off about 10 minutes into it
Bugger.
Some racers are not sure whether to suck or blow.
One day they will find out if they are lucky which is best for them.
However regarding fans , blowing is the only effective way. The reason is that the impellor collects air from a 180 degree sphere and blast it as a jet onto the hot target. If you fit a skirt around the fan body the blast is even more effective.
Now if you were to try and suck the hot air from the target it would have to occupy the 180 degree sphere or cold air would also be pulled in, say from the sides which would have no cooling effect. But if the fan had skirts enclosing the hot target then the air flow would remove the heat .
Also the cooling effect is directly proportional to the surface area that the moving air passes over, so fitting a multi finned heatsink should help the cooling. But beware that sometimes the heatsinks are a poor fit with air gaps between the motor and heatsink and also the airflow can be turbulent and less effective.
I recommend the biggest fan possible as the air moved by the fan blades increases greatly for just a small diameter increase. So use at least a 30mm and up to 50mm square is possible.
Note that fans vary considerably and the airflow of the cheap ones is almost useless
Get a high rpm fan say 5 to 6 volt and run at the 7.2 volt. Also the deeper they are the more effective the blades, so look for a 8 to 10mm deep case, which will also be stronger.
Expect to pay up to £15 for a real high performance fan.
The one I use is 50mm square, 10mm deep, weighs 20gm, 5volt. Airfow rated at 10.2 cu ft/min (or 17.34 cu m /min) Anyone want to work out the litres per sec? I think it is about 4.75.
Anyway that is a good airflow, and keeps my LRP 10.5 brushless from meltdown.
So suck or blow, you decide.
Nick
Now, we are trying to scare people about brushless motors but please try not to get them too hot. We have seen a number of brushless motors burnt out from way too much heat due to over gearing or adjusting the timing ring without knowing the implications.
Remember you cannot abuse these motors like you can with brushed motors. Brushed motors, when they over heat will generally cause the brushes to burnout, com to blacken or even magnets to go off. All of these can be fixed by new brushes, a skim and the can also be re-magnetized. Brushed motors very rarely will have the windings melt as the brushes will generally go off before this has happened.
When most makes of Brushless motors and too hot, it will cause the windings in the can to melt along with other components inside. The can on a brushless motor is the expensive part! Sorry their is noooo repair service for this abuse.
Bottom line:
1) Do NOT over gear them.
2) Monitor the temperature as per the manufacturer’s recommendations.
3) Keep them cool with a couple of fans and a heat sink especially in the summer. If you are using LiPos then you have no excuse for the additional weight of fans. 2 fans will not slow the brushless motor down as they take minimal wattage.
Just because your mates motor has not burnt out on the same gearing does not mean yours will not. We all have different driving styles. Some are smooth and some just hammer the throttle and brakes.
Another note is that when using brakes on brushless motors, the power is taken far more from your cells. Brushed motors have stronger magnetic field and will slow down quicker. Brushless motors need to have their pulse reversed to get them to slow down quickly. This equals more heat and more power taken from your cells.
We all want our cars to go faster that the next person. Just be careful.
I will try to get a picture up of some burnt out windings to show you the damage.
Testing down Aldershot track today, trying to go faster.
I used to be quite good , but am off the pace now, probably due to lack of testing, but more likely just getting worse with age.
So , took the 3rd hand Cyclone , Moorespeed down to see if I could tweek my lap times. Hoped to find 0.5sec a lap with clever adjustments.
Car felt good at start but already o.5 sec slower than Nigel who has the new TC. Also was slowest of the 4 of us testing. Looked at their setups which are a lot different from mine. I was trying the new XRay black springs, 2.6 rear and 2.8 front, which I’m told are the new in thing. Nigel however still uses the HPI silver springs front and rear. I also use the 1.4mm roll bars front and 1.5mm rear, while all others use a soft copper 1.2 mm rear.
I try the 1.2 mm rear bar and find the car perhaps has more rear grip, but i push harder making the back hang out sideways exiting corners. I go back to the heavy rear bar.
I try Jons cyclone which looks good, only to find it has no steering, I understeer straight off the track on the sweeper. He says to take a high line into the curve, sweeping in, but I usually enter low and hug the wall, which will not work. I understeer at every corner and give it back.
It seems I drive with extreme steering and cannot drive with any understeer. I guess that is why the back of my car often jumps from side to side. However I persevere. I reduce rear toe block from 3 to 2.5. On the Cyclone you never know what you will get with the rear toe, as they seem to have random angles from 4 degree to zero depending on your luck. Mine seems reasonable for a clockwisde oval so I carry on. Car appears the same so I leave it on.
After a few other adjustments, nothing makes much difference. So finally put on some almost new tyres (Sorex 32). Car immediately responsive, hanging on and plenty of steering. Times are best I have achieved all day.
So, all I learnt after all, was that new tyres are better than anything else if you want to go faster. But we knew that already. I think my memory is going as well as my driving.
Nick
We did send this out in a news letter but for those that do not subscribe, here are some facts. We where doing some testing on brushless rotors with tools that show digital readouts of the magnetic fields for the Novaks and Orions. We discovered that the Novak rotors seemed to have a much more consistent magnetic field, but was 15 - 20% lower on average compared to a Orion rotor. However the Orion rotors did have a higher field on the best we tested but where more random. Of course the magnetic field is by far not the only factor to take into account. The diameter of the rotar, timing, bonded/sintered, windings and thickness of the windings, etc.
Anyone as we have been making brushed motors for many years now, we are looking at key factors of what makes a good Brushless motor and will be developing our own in the near future. So watch this space as they say.
If you are after a cheap LiPo charger as a spare or are just starting off then click here. We originally got it in for testing to see how it would perform. It does work fine but most of you seem to want LCD LCD and just LCD displays. Nothing so fancy on this one but it does the basics.
Just a quick note on the Trinity DPD dischargers. We are selling them off very cheap to clear them. Nothing wrong with them but we just bought toooooo many (oops Nick!). They did retail for around £110 or so a little while ago. Maybe the price will tempt you.
We have decided to start getting back into Off Road 1/10th electirc again. Such as the Schumacher Cat, Associated B44, etc. We used to cater for these a long time ago. So rest assured we still know what we are talking about. We are just waiting for our stock to arrive. Tempted to get a B44 myself exept using it over the winter many years ago with pressurized water cans to clean them did put me off. We shall seeeeee.
Well I tried revamping our store banner at the top of our site but I am not too impressed with it. If anyone can do a good one for us then it will stand for a long and we would really appreciate it. Or even if you have any suggestions. Let us know.
Thought I would get myself a Race spec 10.5 Orion so will be trying it on the 6th July down at Aldershot club. Should be pretty good from what we have seen and heard.
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