Twin Hammers Kit - electronics recommendations

[gfmucci]

I'm a noob for crawling/rock racing, and I don't own a Twin Hammers, yet, but expect to acquire the KIT form in a short while.

What is the best combination of ESC and motor for this vehicle? Is brushed recommended over brushless? If so, why? What are the pros and cons for brushed and brushless in this application?

I expect to do equal crawling and higher speed (20 to 25 mph?) to take advantage of the 2 speed tranny, so I guess this combo would be a bit of a compromise for each task.

The budget:

Hammer kit: $249
Airtronics receiver: $110 ish ( I already own the Airtronics MT4 controller)
Sensors for receiver: $23
Servos: $100 ish (for 2)
Moter/esc: $110 ish

Thanks, Jerry

 

[Fantuzzi]

I had my TH equipped with 19T and then 17T brushed motors and the stock ESC. It worked well for my style of crawling and trailing. The chassis can't handle higher speeds well like a buggy, so the brushed combo was OK, but still kind of mild in open terrain.

To get a little bit more thrill, I just installed a LRP 10.5 brushless motor with a fully programmable SkyRC ESC. I did not try it yet, but I played around with 0° start timing and the turbo timing to extend the range of use. On the bench it looks very well, responsive in low and it blows the wheels on full throttle in high. I'm keen to try it out on the trail and I will update my driving experience with this combo.

 

[meatmonkey]

I happy with my current setup of a Gen1 Tekin Redline 17.5 turn, geared 24/82, powered with a Traxxas ET3-s (cheaper MMP alternative on ebay) on 2s 2200 lipo.

I'd say it crawls pretty darn good in low for a brushless setup, but still tops out in the mid teens in high. Runtimes range from 45 minutes while trail running, to less than 20 minutes if I'm bashing in snow.

If you really want 25MPH and keep decent crawling you'll probably want to go with 3s lipo, otherwise you'll have to gear so high on 2s that it won't crawl well.

If you were mostly focused on crawling then a brushed setup will provide slightly better "creep", but if you expect it to go fast as well then you are stuck doing regular motor maintenance, such as comm cleaning, replacing brushes, etc.. I mainly went with brushless because I didn't want to have to pull the cage off very often.

This is also the reason I run a Hitec 7950 steering servo. The stock sliding rack binds badly and makes life hell in general for your servo, so pick a strong one, or get the St. Erie bellcrank kit.

You can get away with a cheaper ($25 Hitec 225) shift servo as long as you properly set your endpoints. I'd suggest a Hitec 7954 for the steering, unless you can afford the 7950.

 

[gfmucci]

What makes brushed a bit better than brushless (and sensored) in crawlers. What motor or driving characteristics give it the preference for most folks. Is it just the lower price, or the way it runs?

It looks like I need to take my high gear speed expections down from the mid 20''s down to the mid teens.

I also undestand the SENSORED brushless provide smoother running, a less "coggy" feeling at low speeds. Is that a characteristic of brushed as well?

 

[Sr.Irie]

Here is my setup that works for me
ESC: Mamba max pro set on full sensored mode, water proofed
Motor: Turnigy TrackStar SCT 5T Sensored Brushless Motor 4150KV
Battery: 2S 4200
Gearing: 32t/ 78t

My Twin Hammers will do just over 30MPH in second and in first it will crawl slow and smooth with no heat issues with motor or ESC. VIDEO. This motor is cheap for what it is, basically the price of a good brushed motor so if I do kill one in water I am not out allot of money. I have gotten it pretty wet (not submerged) and at one point it was so filled with mud it made a funny noise and did not turn so good, but still it has not died. That is the only down side I have found with this motor is the open can it lets junk in and I must clean it out from time to time.

If it were me I would not even look at brushed motors any more and would go sensored brushless only. To keep a brushed motor working well there is maintenance that should be done every few batteries, new brushes, turn the commentator, ect. I have done that sort of thing for years and do not want to do it any longer. Brushless you just have fun and run it.

 

[MeanTT]

Here is my setup that works for me
ESC: Mamba max pro set on full sensored mode, water proofed
Motor: Turnigy TrackStar SCT 5T Sensored Brushless Motor 4150KV
Battery: 2S 4200
Gearing: 32t/ 78t

My Twin Hammers will do just over 30MPH in second and in first it will crawl slow and smooth with no heat issues with motor or ESC. VIDEO. This motor is cheap for what it is, basically the price of a good brushed motor so if I do kill one in water I am not out allot of money. I have gotten it pretty wet (not submerged) and at one point it was so filled with mud it made a funny noise and did not turn so good, but still it has not died. That is the only down side I have found with this motor is the open can it lets junk in and I must clean it out from time to time.

If it were me I would not even look at brushed motors any more and would go sensored brushless only. To keep a brushed motor working well there is maintenance that should be done every few batteries, new brushes, turn the commentator, ect. I have done that sort of thing for years and do not want to do it any longer. Brushless you just have fun and run it.

Agreed. Why spend the money for brushed, honestly? Are you worried about losing a motor in the wet? If so, buy from China! I have gotten motors that work fine for 20 bucks. Sure they are 3000KV 540 brushless motors, but hey, they will beat the heck out of a brushed motor.

For your price point, I would suggest exactly what Sr. Irie recommended. If you don't care about slow speed stuff, get a Castle Sidewinder system which is what I use. 3800 KV, sensorless and 30+ MPH 4 pole power. You don't need to spend a lot to get a lot.