yet another rcm ext crt.5 :P
 

Alright, so I know there are a million of these builds up lately, so I thought I'd join the bandwagon :oops:

My pics keep getting taken off, so I'll just link to em:

Front top.

Battery side.

Motor side.

Overhead.

With the gear in those photo's the L/R balance is near perfect. Haven't measured it yet, will soon though. It must be damn near 50/50.

Anyway, my MM is broken and I have to make up a battery strap. The battery will be velcro'd in, and the hold down strap will be a piece of bend up 1mm alu sheet that will multitask as a spur guard, top, outer and front/rear roost guard. Basically itll be half a case kinda thing that I slot the battery in before putting it in the car and clipping it on.

I've never had a problem with servo's getting hot, hopefully it wont affect the Rx negatively. I'll mount the MM on the radio tray with the heatsink fins longitudinally and maybe a little cutout in the body (when I get one) for some nice airflow.

I've got electric evader body for free that should fit nicely, its a kinda small 1/10 stadium truck body. I'll just wait n see I guess.

The little wheels do look a little funny :P I'll probably get some traxxas Anaconda's for on road, talons or series dirt hawgs for bashing, and some 30 bow ties for anything a little more racy.

Any suggestions for a better suited wing?

Specs are:

Feigao 9L (2731kv unloaded, + installed ceramic bearingsi had laying around)
MM esc + CCBEC
4000mah 3s U series hecell lipo (20C cont)
TS-160 for steering.
Futaba FASST Rx
Geared 18/46 - unable to drive it with the mamba out of action though, so its all meaningless til then!

Comments/suggestions welcome!

Alright, I've looked through all the wings on tower, and have decided on either Lightning 10 wing, or Robitronic truggy wing.

The stock wing is 140mm (5.5in) wide, and the above two are 171mm (6.75") and 165mm (6.5in) respectively. Anyone tried either of those or have any reason I shouldn't get one of them? I prefer the look of the robitronic wing, but I wonder if a extra 25mm would be enough to bring it to scale?

25 mm is 1 inch, so that should be good. Had no idea that the lightning 0 wing was so big.

Yeah I cant decide.. the robo wing has started lookin funny the more I compare them lol... don't spose you or anyone has a lightning 10 wing to see how it suits an extended crt.5 size wise?? :P Or any other suggestions?

I was planning on using a LS10 wing on my crt.5 to balance the wide truck tire stance, but Amain was out of them the last time I placed an order. I'll have to check out the Robo wing too.

Anyone tried a sidewinder in a .5? I'm thinking of buying one to run in this till I get my MM repaired, then moving the SW into my MLST2 or something.

Any comments/suggestions on a SW + cap, Feigao 9L, 3s 4000mah 20C lipo running in this thing? I was thinking gearing for about 40mph. say a 17 or 18 pinion with the stock spur.

Also added a body. The colours a bit gross, but it fits the chassis as well as any I've seen so far. I think I'll stick with the stock spoiler. I wish there was a wing mount to bring it up higher though.


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Is that an Evader body? Looks like it fits pretty well with little modification.

I don't think a Sidewinder would like it. My truck has almost the exact setup as yours (9L, 3s 4000mah 20C, 18t pinion), except I'm running 2.2 truck Holeshots and with a CCBEC, and the MM heats up to about 140-150 on the track without any caps or fans.

Yeah. it works pretty well. I've got holes all over it now lol from moving it around. I moved it forward a little last night after those shots were taken. It's a little narrow, not too bad.

Hmm fair enough. I was going to run a CCBEC and cap which should help with the temps a little. Well I ended up buying one for the rusty anyway, so while I'm waiting for the MM I might give it a go with a 16t and see how the temps go. Cheers.

Let us know how it works out! I'm definitely interested.

Will do. Pity I'm in Aus and will have to wait ~2wks for shipping :(

I tried a sidewinder in my CRT.5 with a 5700 CC motor. It ran great on 2s, but terrible on 3s. Then I read on the CC site that you're not supposed to run a 5700 on 3s with a sidewinder. Oops.

A BEC might help it run that motor on 3s, but I just swapped it with an MM out of my Axial crawler and now it works phenomenally.

On the wing note, I ran a HB LST10 wing, looked HEAPS better then stock with the EXT chassis big tires, and a truck body

Nice looking .5 man! Clean layout

This is what BOR's EXT CRT.5 looks like now with the bigger wing and 2.8 Anaconda tires. (Thanks again for the great deal BOR!)

http://i192.photobucket.com/albums/z...08865Small.jpg

http://i192.photobucket.com/albums/z...08849Small.jpg

Nice, rusty body is a bit to big, but looks good

Weird seeing it with a new owner lol, kind of cool IMO, thanks for buying it lol, that was like 40 bucks short of my new radio, so it worked out both ways =)

I was just online trying to decided between the LS10 wing and the Mantis wing. Thanks for posting those pics the LS10 wing looks awesome. I just orderd one.

yeah it looks tops! I think ill pick one up too :P

Alright, I've got the battery tray/strap/spur guard/whatever done.

After about 2 hours of making and remaking and refining card templates, I finally traced a pattern onto some 0.5mm alu sheet and cut it out with the dremel wheel, then bent it up and drilled a few holes. It's held down by the posts and also acts as another diff brace.

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With the battery in place:
http://issima.customer.netspace.net....t/Image366.jpg

Then I cut up a bit of 3mm angle and drilled a couple more holes, then put a bend or two in:

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All the extra alloy on the battery side helps balance it a bit, it was a little motor-side heavy before (only very slight though). Haven't checked the balance yet with the new bits, but I'd say its evened it out a but.

That's looking pretty functional.

I like it!

Looks like you will have a hard time damaging the lipo!

It may even be able to take a bullet!

Haha thats the plan! (the not damaging bit that is :lol:)

Well, tyres rock up today. They look hot as too. I love the 30s dirt hawgs:

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I do like the design of that battery cover type thing- like an enclosed sidepod.

Yeah when I'm bashing it's surprising the amount of sticks and twigs I end up with sticking through the swing arms and such. I thought it would suck a but if I hit some scrub and got a stick through the swingarms and piercing one of my lipos... This should prevent that :yes:

Those castle top Dirt Hawgs look a lot more functional than the older style. I do like the look of the 30 series stuff.

yeah theyre Dirt Hawg II's in old terms - been around for stadium trucks ever since I got into RC a few years back. I only just discovered the other kind - got another set of CRT.5 stock rims and the older buggy Dirt Hawg I's to go all round on the mlst2 - something to wear on the road and light offroading.

Ahh I see what you mean about the castle tops now I think - just realised my old ST DHII's have filled in knobbles... makes sense :) The 1/18th dirt hawgs are also this newer 'castle top' style too - I wish they didnt discontinue the 1/18th edges though - not everyone has a 4wd 1/18th! :)

That makes more sense. I bought a set of DHs last year and they were the filled in tops. They worked good on the steet and other high grip areas, but not so good on actual dirt. The new ones look better for dirt.

Alright, maiden voyage with the sidewinder today. Damn this thing is cool! The motor (9L) stayed quite cool even after multiple top speed runs. Then esc was hot and batteries were warm (sorry no temp gun :P). I added some caps to the ESC and cut out a bonnet scoot for some airflow, and the ESC runs only just warm now. Huge improvement!

I think I might try and get some ventilation on to my batteries though, for 4000mah 20C batteries they got quite warm - although that was driving it as hard as I could (on the road, full throttle/brake bursts everywhere). Timing was set to normal and start power to low. I might have a fiddle with that and see if I can get it to improve much. Gearing is 18/46 and it has a very respectable top speed (running anacondas atm).

Initially the front wheels were unloading easily, so I went to up the oil weight an saw the thin was basically empty stock, so I half filled it with 10,000 and its a lot better now. It will wheelstand on the road but not too easily, only if you plant it. 7k probably wouldve been better if I had some. Still. This thing sure is a rocket! - I'll have to look into getting some better cells or ventilation though. Or I could just gear it down lol - will see how it goes. A few pics: Notice there is a plug hangin around there - I wanted to disable the BEC in the sidewinder, but am guess I still need to have the red wire in for programming purposes. Didn't have a servo extension, only a Y-connecter.

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That spur cover looks sweet. Top job. Haven't got a template at all :yipi:

Cheers. No template unfortunately, I made one out of this cardboard, just kept trimming it to shape then traced it onto the alu sheet and cut it out with a dremel wheel. wasn't too hard.

Alright, so I'm thinking about upgrading the battery. Has anyone had any experience running the 9L on 4s? at nominal (3.7v/cell) voltage it would be free revving to a hair over 40,000 so I'm a little worried about heat issues. I run an RCM heatsink (as you can see) but have also replaced the motor bearings with ceramic ones. Not that it has anything to do with the lack of effiency of the motor at high rpm, i figure every little bit helps.

I'm looking at a 2200 4s pack which is much more light weight. Was thinking of gearing it to the same speed (~42mph according to Brians calc). Either that or just gear it down with these batteries... they are getting a little toasty in there.