Upgrade to Brushless Motor for Dark Impact Advice Wanted

[Wooders28]

WOW,

Thanks for the information,quite concise!

So brushless run a bit like 3 phase motors.

I had a feeling the motor would run hot in that position,had trouble with that when racing the Optima Mid,i was at high school at the time though and had access to a vac former and redesigned the Mid body to include an air scoop which seemed to work quite well.

Good plan with the heat sink Mark,i think i still have the mold somewhere from the Mid,just need to make a vac former!

The only cell i had split was on a NiCad saddle pack (in the Mid) but i think that was just because they where loose cells taking a battering.

You guys on here know your stuff,

Thanks for the info.

[mike_o]

... Sensorless systems run cooler....

Interesting, why is that?

[TA-Mark]

I had a feeling the motor would run hot in that position,had trouble with that when racing the Optima Mid,i was at high school at the time though and had access to a vac former and redesigned the Mid body to include an air scoop which seemed to work quite well.

Good plan with the heat sink Mark,i think i still have the mold somewhere from the Mid,just need to make a vac former!

The Dark Impact body has side pod vents already moulded into the body. They are just closed over, and a decal to stick on them to simulate a vent. If you look close at the pictures in my showroom, I carefully cut the vents out and covered the holes with some fibreglass fly mesh glued in from the inside to keep the rocks out, then painted them semi-gloss black.

The closed in motor is more a problem with the chassis being so enclosed. There's no room for the usual clip on heatsinks or motor fans without cutting and weakening the chassis.

[TA-Mark]

Interesting, why is that?

Sensors are terribly inaccurate for motor timing purposes as the motor's magnetic fields change under load or at high speed, that's where sensorless is more efficient. Motor efficiency is lost mainly as heat.

[speedy_w_beans]

Interesting that sensorless runs cooler. That doesn't align with my experience, but maybe it was a problem with my setup.

I've run two different motor systems in a 1/10 RJ Speed pan car to do some speed runs, and the sensorless system definitely heats up more quickly. The first ESC/motor combo was a Novak Havoc 2S with 5000kV motor (their old Havoc sport system), the second ESC/motor combo was a Castle Sidewinder SV2 with 5700kV CM36 motor. In both cases I had the cars geared identically at 5:1 with 16T pinion and 81T spur.

With the Novak system I could run the car up and down the street as much as I wanted with minimal heat; I could touch the motor and ESC no problem. With the Castle system I couldn't go more than 5 minutes before hitting 160F or higher temps with an infrared gun. Also interesting is that the back of the motor can (the black part) was hotter than the can itself (the green cylindrical part).

With respect to 4WD buggies, there is a big difference in gearing recommendations between Novak and Castle for the same application. Novak recommends something like 9:1 for their 5000kV motor in a 4WD buggy; Castle recommends anywhere from 12.5:1 to 16:1 for their 5700kV in a 4WD buggy. If you shoot for 14:1 with the Castle, with a 78T spur in the Dark Impact you need a 17T 0.5 module pinion, which I'm not sure exists (at least from Tamiya). I've bought Tamiya's 23, 25, 26, 27, and 29T pinions in the past and don't recall seeing anything smaller; maybe Robinson has something. If you shoot for 9:1 with the Novak system, then the Dark Impact's stock 26T pinion should be in the ballpark.

I've also tried the Castle system in a DF-02 with no body shell, and with a 16T Novak pinion (11.3:1) the motor would get hot within 5-10 minutes of hard bashing. Even mounting fans to the motor and ESC couldn't keep the motor temperatures under control, but the ESC did well with the fan.

Now, to be fair to Castle, I bought their SV2 system when it first came out and shipped with the CM36 2-pole motor. Now that the SV2 system is shipping with the 1406 4-pole motors, the gearing recommendations may be easier to deal with. I don't own a 1406 or 1410 4-pole motor, so I can't comment on it specifically.

It'll be difficult to keep the motor cool in a DF03 Dark Impact just because of the way the motor is cocooned in the middle of the chassis. I also had to start rebuilding the rear diff a lot more often, and I also killed the aluminum gear on the slipper shaft inside the rear gearbox. After trying Novak 8.5T, 10.5T, and Castle CM36 motors in my son's Dark Impact, I wouldn't recommend doing it at all. My opinion: go for 3300kV, or sell it and get a DB01 instead; there are more opportunities to gear the system properly and address heat issues with venting. I've had better success with the DB01's ball diffs and belt drive.

-Paul

[TA-Mark]

You left the default ESC setup in the Castle system?

I ran the 5700Kv with 21T/85T and the 4600Kv with 23T/82T in the DF03. Not overheat issues, but then again, I did set the ESC up.

The gearbox is solid once you can get that Five Stars steel mainshaft. I was lucky to get 10 packs through it with the 4600Kv and the aluminium geared mainshaft.

[speedy_w_beans]

Yes, I actually went for the least timing and the most punch control, and it didn't help much. I did have the heat sink bars and a slipper clutch installed as well. I didn't get the hardened spur shaft -- by then I was done fiddling with the Dark Impact and Castle's motor. In the end I rebuilt the Dark Impact from scratch using replacement parts, painted the shell per box art, and now it's a shelfer in my son's room.

The Sidewinder SV2 ESC seems like a good unit -- it didn't get too hot without a fan, and with a fan it was great. My only problem was with the 2-pole 5700kV motor itself. I've been tempted to get a 1406 or a 1410 and try again, but at this point I'm pretty happy with Novak's Havoc and GTB2 systems.

Nice chart; at least it shows 13.6:1 is possible.

Take my experience as a single data point, no more, no less.

-Paul

[RS2RSR]

The fastest motor setup Ive tried in my DF03 is a Novak550 4.5 on 14.8v lipo.

Wheelies all day! It was also very impressive with the Novak 3s/8.5 Ballistic on 3 cells.

But now its back to the Novak 6.5. Completely undriveable on 3 and 4 cells, but very fun.

Had problems with the rear diff melting, but never had a problem when I rebuilt them with ceramic balls.

Read somewere that a guy heated up the aluminum gear, took it off and replaced it with a steel one.

[TA-Mark]

Read somewere that a guy heated up the aluminum gear, took it off and replaced it with a steel one.

That was probably on the RC Tech forum, DF03 thread. One guy there was pressing off the worn gear from one slipper mainshaft and heating up and pressing on another unworn aluminium gear from a disused standard mainshaft.

I had one shaft ground to 3.2mm where the gear sits and fitted two 0.6 module 18 tooth pinion gears onto the ground shaft. While better than the factory mainshaft it wasn't ideal.

[RS2RSR]

That was probably on the RC Tech forum, DF03 thread. One guy there was pressing off the worn gear from one slipper mainshaft and heating up and pressing on another unworn aluminium gear from a disused standard mainshaft.

I had one shaft ground to 3.2mm where the gear sits and fitted two 0.6 module 18 tooth pinion gears onto the ground shaft. While better than the factory mainshaft it wasn't ideal.

Good thinking

I found some helicopter pinions that has a 5mm hole and 0.6 module, but I need help to cut them smaller as they are too wide..

[RS2RSR]

Just ordered 3 sets of the FIVE STAR FS-7039 main slipper shaft from RC-Champ and just wanted you guys to know that FIVE STAR still have them in stock.

Just send RC-Champ a mail. The price wasnt bad either.

[Wooders28]

Just ordered 3 sets of the FIVE STAR FS-7039 main slipper shaft from RC-Champ and just wanted you guys to know that FIVE STAR still have them in stock.

Just send RC-Champ a mail. The price wasnt bad either.

Been trying to find the FS-7039 slipper shaft but having no luck.

Tried RC champ and a few others

Will setting a loose spring tension on the slipper help?

Ended up getting the Castle Mamba Max Pro ESC + NC5700kv Motor brushless set up.

[TA-Mark]

Will setting a loose spring tension on the slipper help?

Nope. I wore out two of them with silvercans (about a year's worth of weekend running). Got less than 10 packs with a Mamba 4600Kv before the mainshaft was toast. I have correctly adjusted slippers on all of them. I'm yet to wear out either a FS7038 or FS7039 mainshaft and they've been in there for some time now.

[Wooders28]

So are there any other options if i cannot find the 'golden fleece' of the hardened main shaft?

Am i going to have to manufacture one myself?!

[atf300]

wups,

my bad , didn't read it properly.

hope you have luck with finding them

[RS2RSR]

Running 81t 48p spur gears for the Team Durango cars in my DF03`s now and finding pinions is no longer a problem. Need to use the slipper pads from the Durangos also..

Using a carbon chassis the motor get much more cooling. Carbide balls in the rear diff and ceramic in the front.

Still running the Ballistic 6.5 and no broblems with the drivetrain

[Wooders28]

I found some helicopter pinions that has a 5mm hole and 0.6 module, but I need help to cut them smaller as they are too wide..

Just taken delivery of said pinion,

http://www.fast-lad.co.uk/store/revco_hard_revco_pinion_shaft_ho-0600lh-18t-p-13181.html

A little wide,better than not wide enough!

Nothing an angle grinder wont solve.

Hopefully press the old one off and this one on at the weekend.

Is the 'Tamiya 53124 3mm Tungsten-Carbide Diff Ball Set' worth purchasing just to bullet proof it or is that not required?

[RS2RSR]

Just taken delivery of said pinion,

http://www.fast-lad....8t-p-13181.html

A little wide,better than not wide enough!

Nothing an angle grinder wont solve.

Hopefully press the old one off and this one on at the weekend.

Is the 'Tamiya 53124 3mm Tungsten-Carbide Diff Ball Set' worth purchasing just to bullet proof it or is that not required?

My opinion is that the diffs last much longer between rebuilds with carbide or ceramic diff balls.

[Wooders28]

My opinion is that the diffs last much longer between rebuilds with carbide or ceramic diff balls.

Might invest,Only about £15,so not to expensive either.Hardened gear cut and pressed onto the main shaft.Easy enough to do too!

[jijohans]

Just taken delivery of said pinion,

http://www.fast-lad.co.uk/store/revco_hard_revco_pinion_shaft_ho-0600lh-18t-p-13181.html

A little wide,better than not wide enough!

Nothing an angle grinder wont solve.

Hopefully press the old one off and this one on at the weekend.

Is the 'Tamiya 53124 3mm Tungsten-Carbide Diff Ball Set' worth purchasing just to bullet proof it or is that not required?

How did this work?

[Wooders28]

How did this work?

Worked quite well, no gearbox or diff issues what so ever!

but

It turns out that a Castle 5700 brushless system and a 3s Lipo in a DF03 chassis is a handful.(Who would have thought!! lol)

Issues with the damper shafts bending and snapping,(uprated towers needed)

Gearbox ripping the bolts out and separating from the chassis,

Snapping drive shafts etc etc.

Good fun though.

[mman2005]

Hi all. Recently purchased a DI and haven't gone down the brushless route before. I already have a TBLE-02s esc and was looking at TBLM-02S 15.5t or 1.5t brushless motor. I understand I will need a cable but wanted to get some advice on what people thought would be a worthwhile upgrade. I have been running a sport tuned brushed motor until now on other cars. I want to avoid upgrading loads of parts, e.g. pinion, slipper clutch, etc. I'm not looking to race and wanted to know whether a 15.5t or 10.5t would be more suitable for my needs. Any advice would be greatly appreciated. Thanks in advance

[ThunderDragonCy]

In my (extremely) Limited experience the tamiya motors seem very very expensive for what they are. Modelsport made me up some tamiya plug leads for my speed passion motor to run on the tble-02s if you don't fancy soldering.

My Thunder Dragon is handling 10.5t no problem so I would think a dark impact would too.

[Buggyjam]

On 18/02/2014 at 0:42 PM, Wooders28 said:

Worked quite well, no gearbox or diff issues what so ever!

but

It turns out that a Castle 5700 brushless system and a 3s Lipo in a DF03 chassis is a handful.(Who would have thought!! lol)

Issues with the damper shafts bending and snapping,(uprated towers needed)

Gearbox ripping the bolts out and separating from the chassis,

Snapping drive shafts etc etc.

Good fun though.

I run a castle 57 with a mamba max pro in my neo scorcher. It's indeed a handful. Buggy is maintenance heavy, like 2/3 of my tiny collection. Currently it's in the shop needing a complete tear down. It has a snapped towers, skid plates finished, metal drive shafts worn despite maybe 6 runs, tyres shot (Proline dirt hawgs), metal a arms deeply stone chipped and CVAs are now junk ha. It's the kind of setup where every few runs you know you're going to be replacing something. Great fun though. 

[Wooders28]

10 minutes ago, Buggyjam said:

It's the kind of setup where every few runs you know you're going to be replacing something. Great fun though. 

It's just the actual gears (bar the heli mod slipper gear) and body I've not replaced yet! lol

She took 5S not too bad either to get top (For now) of the 4wd speed runs 😁