RC4WDs New Micro Crawler

[Aeronuclear]

Good thinking Jimbo wa, I saw a YouTube video of a red D90 1/18, by Alan ch, which I believe is also using a double motor set up. But his reverse was a lot quicker then forward. Looks good... Update us when you mounted yours.

How are you linking them electronically, can the ESC take it? How did you fix the gear motor to the vertical 'checker' plate?

[derycksan]

Finally got her back together after paint, lights and fpv install. Need to clean up wiring though.

Sent from my SM-G900P using Tapatalk

[Sparks1337]

Say hello to my little friend...

V2 works, like a dream:





And fitted in the chassis:




Its only done a quick turn around my study with the electronics hanging off the back, but I can confirm it rocks I'm stoked, and mightily relieved. And I've got very sore fingers ;)

Video to follow

[Shape_Shifter]

Originally Posted by Sparks1337

Say hello to my little friend...

V2 works, like a dream:





And fitted in the chassis:




Its only done a quick turn around my study with the electronics hanging off the back, but I can confirm it rocks I'm stoked, and mightily relieved. And I've got very sore fingers ;)

Video to follow

Nice work!

[Sparks1337]

Here is a quick vid

http://vid1081.photobucket.com/albums/j346/mungo1337/RC%20Cars/1-18GelandeBigBlock%201_low_zpszzabras2.mp4

[Sparks1337]

Video quality doesn't help, and I was going full tilt forward and reverse for most of it. It does have low speed control as seen in first part of vid, but a 3:1 reduction would be better. Bags of power and still relatively high gearing means it is a bit jumpy when thrown about

[spoo76]

That's similar to how I figured a divorced setup would go. Mount the motor and spur up front and use a shaft to connect to the pinion in the transfer case. It would also make more room for a bigger spur for more reduction

[Sparks1337]

Yeah I looked at a divorced setup but there aren't many mounting options, and this saved the faff of an extra shaft and uj's etc. There is room for at least a 54T spur in there as it is - I'm planning v3 with a 48T spur and ballraces. I'm hoping the bigger spur will push the motor high enough to allow me to use the 180 can, we'll see

[spoo76]

A mount for a divorced motor should be easy. Make a flat motor plate for the motor pinion and spur. Make a bracket to attach the motor plate to chassis rails. (All similar to 1/10 and SCX setups) and then connect the output to a driveshaft

[Sparks1337]

Easier said than done for sure and to what end? You'd be throwing the motor weight even further to the rear. To get the motor at the front you either have to flip the tranny or drill through the front of the case in exactly the right spot. Drilling that accurately isn't easy and you get one shot. Flipping this tranny raises the height of the output shaft, meaning no more nice metal shafts and nasty angles, I tried it. In any case, putting the motor right up front loses the only forward mounting spot for the battery, negating any weight bias advantage. I looked at all the options and doing it this way keeps the tranny stock and the motor weight low down and out of the way, if rear biased. Best compromise available imho

[spoo76]

Ahh I didn't know about the Trans output. As far as weight bias the mount and 130/180 motor should way more than the battery. I would have assumed with the lack of interior the battery could be mounted where the seats or front foot area would be. Its hard to tell without having one here.

[Shape_Shifter]

Originally Posted by Sparks1337

Here is a quick vid

http://vid1081.photobucket.com/albums/j346/mungo1337/RC%20Cars/1-18GelandeBigBlock%201_low_zpszzabras2.mp4

It looks like a great overall gear ratio! Does it have the torque to crawl slow over, say, a step, or does it stall until you stab the throttle?

[tacocat]

Originally Posted by Sparks1337

Here is a quick vid

http://vid1081.photobucket.com/albums/j346/mungo1337/RC%20Cars/1-18GelandeBigBlock%201_low_zpszzabras2.mp4

If you sold that motor set up I guarantee every single 1/24 gelande owner would buy one.

[Sparks1337]

@ Spoo76 sorry it was getting late and I was feeling tetchy - once you have it in your hands you see the options start to evaporate I'm sure a divorced setup could be made to work but it was beyond my limited comprehension! The batt is 850mah so quite a brick to offset.

@Shape shifter I just tried it over a big book. Ignoring the terrible approach angle, it still stalls out and chirps until at least half throttle is applied - it really needs a bit more reduction, but manages pretty well now at crawling. I kinda like that it runs around at a decent walking pace though, good for trailing.

Tacocat wish I had the means to mass produce, or at least sort out a few of my fellow sufferers on here I only had the one gear though, and it was all done by hand, very slowly...

[Shape_Shifter]

Originally Posted by Sparks1337

@Shape shifter I just tried it over a big book. Ignoring the terrible approach angle, it still stalls out and chirps until at least half throttle is applied - it really needs a bit more reduction, but manages pretty well now at crawling. I kinda like that it runs around at a decent walking pace though, good for trailing.

Try 3S if you can.

[Aeronuclear]

All, I managed to contact Alan ch who mod his for crawling, I speak his language. He sent a video:
https://m.youtube.com/watch?feature=...&v=UeNwHsZ_BxE

It's a double motor set up. I will find time to translate and post.

[Aeronuclear]

Originally Posted by Aeronuclear

All, I managed to contact Alan ch who mod his for crawling, I speak his language. He sent a video:
https://m.youtube.com/watch?feature=...&v=UeNwHsZ_BxE

It's a double motor set up. I will find time to translate and post.

The translation basically goes like:

Install 2 no. reduced gear motors in place of original trans. The motor he used is shown in the link below:

商品詳情

It's a 200rpm motor. He has upgraded the ESC and connect the motor in series.

Next he talked about the mounting, this is the part that I haven't quite figured out clearly yet. Direct translation goes like this: I have soldered a copper rod on the reduction motor, with tapped hole and fixed this on the chassis.

He next mentioned that he cut 1/3 of the stock Spring away to allow for more flex. And has reduced the amount of foam in the tyre.

A video of his truck:


https://m.youtube.com/watch?list=LLb...Uk&mode=NORMAL

Can someone figure out the mounting bit?

[Sparks1337]

Sorry Shape Shifter no can do, I don't have an esc that'll cope with 3S.

I did a quick back-to-back indoor trial against my big block losi to get some kind of benchmark instead. Identical motor, identical tyres and I think a 16/59 pinion/spur.

The RC4WD definitely requires more throttle to get it moving, and although it has reasonable low-speed control, I was having to give extra little squirts of throttle to get the RC4WD up and over some small steps, while the losi walked it on tickover.

Top speed is more or less identical, the landy was just starting to pull away after a 1.5m sprint, about a truck length in it maybe. More closely matched than I expected.

Then I weighed both trucks. The losi fully loaded with a 1/20 body is 330g. The RC4WD fully loaded is 530g

No real test but I'd say this thing needs more reduction - although going 3S might be an option...

I'm gathering parts for a 3:1 version of my box but it may be that 4:1 would be better given its extra weight. The motor has plenty of power at higher revs, but lacks torque for the low-speed fine control stuff.

One thing is for sure - adding power just highlights that this thing is not a natural crawler. Even with the mods to steering knuckles, lower links and shocks the losi ran rings around it - and that is running a crawlerx leaf chassis.

The front approach angle sucks, the axles are too wide and the pumpkins drag and catch everywhere. Bigger tyres will help, but I'm starting to feel like I'm kicking a dead dog.

Still, at least my handiwork is holding up to the abuse - so far anyways

[Sparks1337]

@Aeronuclear, I think it means he soldered a rigid copper cross-brace to the motor can and then bolted it to the chassis at either end. Same idea as Jimbo-Wa's above but with different mounting technique I'd guess.

[crawler will]

I don't know if it is just mine but has anyone else not been able to control their speed like as in you pull the trigger and it just goes full throttle?? Because it seems that with my divorced Losi transmission setup and the stock receiver/esc and transmitter it does this. But I tested my 2 channel futaba receiver and transmitter with one of those mini esc that are in clear heatshrink and I was able to crawl real slow but still give it some gas, however I think my receiver is buggered because when I let it rest and not touch the controls it starts jumping and takes off randomly, anybody know why that might be?????