Kronos XTR 2022 build by DaniC

[DaniC]

All right guys! I've been drooling over the Kronos KTR 2022 since it came out, and I've finally pulled the trigger!

I bought it last night from eurorc.com, very nice website specially for those in Europe. Same prices as buying direct from corally.com, but much cheaper shipping and a 5% discount. The XTR + Torox 185 + Kuron 825 = €706.85, pretty decent I think! I had already bought servo, Rx/Tx and a few other goodies.

Anyway, starting this thread to share my build, this is what I'm putting into the XTR:
- Torox 185 ESC
- Cappack 35V 6800µF (self made)
- Kuron 825 Motor
- Heatsink with Dual Fan (link)
- Promodeler DS630BLHV Servo (plan to run it at 7.4v)
- DumboRC X6FG Receiver with the X6 Transmitter
- Corally Wheelie Bar (C-00180-567)
- Sketer Roll Cage Foam (C-00180-834)
- Shock Cap Protectors (C-00180-658)
- ARP Design Mug Guards
- ARP Design Shock Protectors
- ARP Design Center Tower Pin Holders

I have everything bought and ready, just waiting for the XTR, ESC and motor to arrive. I've DIYed my own cappack, bought a bunch of 680µF capacitors and built one for the XTR with 10 of them.

Here's the final result on the cappack, I couldn't get the heatsink to fit nicely so I went with self-amalgamating tape instead, and covered the PCB with liquid tape so between those two things it's pretty waterproof.

I can't wait to get building!!!

 

[BashingBrian]

Look forward to seeing it..!!

 

[DaniC]

Look forward to seeing it..!!

Thanks man! I'm pretty excited about this one.

I think one of the first things I'll do is the whole drywall tape + shoe goo to reinforce the body. Although I don't use shoe goo, I just use spray adhesive and works great and it's not as messy.

 

[BashingBrian]

Although I don't use shoe goo, I just use spray adhesive and works great and it's not as messy.

That's interesting, do you have a link to the adhesive that you use

 

[DaniC]

That's interesting, do you have a link to the adhesive that you use

Sure, I think there's a good few that would work. The last time I used this Bostik adhesive spray on my Traxxas MAXX, that was over a year ago and the body is still holding up. I documented the process on this forum.

 

[DaniC]

My XTR has arrived!!! Oh man, I'm so impressed with the quality of this thing! I can't wait to build it up and get bashing! More on that soon.
Only issue so far, the driveshaft came bent, already opened a ticket with them to get a replacement.

 

[DaniC]

She's ready to rip!

This is how the build went the the things I learned.

1. The ARP Design mud guards are fantastic, they fit perfectly and they look great, highly recommend them.

2. The ARP Design shock protectors are also very well made, they fit perfectly and they actually replace the spring retainer at the bottom, it even has the 1/4 twist locking mechanism like the stock ones have. They are made of a hard plastic, I think I would like to see these made in a more flexible plastic, minor complaint. Also, note that these don't seem to fit too well in the back shocks, I think they're intended for the front shocks only, on the back the spring kinda catches with the plastic. I had bought four of these but took the back ones off because of this. That's ok, don't really need them in the back, specially with the mud guards on.

3. The ARP Design center tower pin retainers are a massive improvement over the tiny o-rings to come with the truck.

4. The shock cap protectors are a good improvement. They actually replace the plastic inserts that go between the standoff and the shock cap.

5. While the shock caps are good, notice that because they're bigger they will touch the body at the front and it will actually be a very snuggle fit to put the body clips on. But they do fit, you just have to push the body down a small bit and then insert the clips. I actually prefer this as it makes the body fit snuggly and removes the awful lexan rattling noise.

6. The Corally wheelie bar is very nice and very solid. But perhaps too solid so we'll have to see if it survives landing on it or something like that. At the bottom it's supported under the diff case and at the top it replaces part of the wing mount.

7. The Torox 185 looks great and the receiver cable is plenty long to go under the battery tray and into the receiver case. I do worry about the cables rubbing against the plastic as you see in the picture. I thought about cutting a bit of the plastic, but I didn't want to take things apart to do that so went the lazy way and just put a strip of gorilla tape over it. Also, the ESC comes with a cappack already installed. So the cappack I made a couple of weeks ago will have to wait.

8. My choice of servo fits great and has loads of torque and is fast.

Some other thoughts:
- The Sketer tower foam fits very well, I just took a small bit of the front so now the foam follows the shape of the body.
- I took the diff out and put a small blob of 20mil diff fluid I had, it felt very loose so hopefully this will reduce ballooning a bit.
- On the servo horn, as well as loctite I also put a locking washer as I've had these screws back out very easily in the past.
- Didn't open the shocks but they fell good, seems like they where properly built.
- Didn't bother to open front and rear diffs, I'll do that on the first service in a couple of weeks.
- All screws and nuts where properly installed, nothing came loose and good amounts of loctite where used on all metal to metal fixings.
- Working on this truck is easy, but time consuming because of all the bracing and extra screws and catching nuts.
- As mentioned before, the center-back driveshaft came bent. And after having taken the center diff out I understand why! It's very hard to put the diff back in along with the front and back driveshafts, it nearly feels like you need to force them in, and it's very hard to ailing the whole thing. I actually thought I would have to either take the motor mount of or the front and rear diff cases off. It's because of all the bracing, the angles needed to put the shafts in and push the diff down into the mount it just means the shafts hit the braces. Anyway, spent a good half an hour trying to put the diff in without having to take everything apart, and without forcing the shafts. In the end I managed, but it took loads of patience and precision.
- To feed cables in/out of the receiver box means you have to take it off the chasis, 6 screws.
- I'm waiting for the motor heatsink and dual fans to arrive.

Overall guys I'm super impressed with the quality of this truck! I can't wait to try it out, but of course today is raining and don't want to get it all dirty and muddy the very first time I use it.

 

[BashingBrian]

Looking good..
My advise is to cut the side guard , you'd be surprised how quickly that plastic will cut through those wires..!! The tray wobbles around unless you have added the extra screw underneath..

P.S. where did you get the servo from.???

 

[DaniC]

Looking good..
My advise is to cut the side guard , you'd be surprised how quickly that plastic will cut through those wires..!! The tray wobbles around unless you have added the extra screw underneath..

View attachment 2425

P.S. where did you get the servo from.???

Yeah you're absolutely right man! I'll cut the side guard, otherwise I'll regret it! That bit of gorilla tape I put there might protect it a bit, but will eventually chew through it.

I buy Promodeler servos directly from their website, they're pricey, but best in class IMHO.
https://www.promodeler.com/brushless-servos.aspx

This one I put on the XTR I brought it myself from a trip I had to the US a few weeks back, it was shipped to the hotel. But I usually get them shipped to an address in NJ using a post forwarding service (AddressPal in Ireland) and they take care of customs and tax etc. I'm sure you have similar stuff in the UK.

 

[DaniC]

Done, removed a bit of the plastic side guard so it doesn't rub against the ESC cables.

I noticed one more thing around this area, if you feed the throttle cable vertically down and under the ESC mount (blue line in picture below) the cable will rub slightly against the bottom of the side guard where the screw goes in (red arrow in picture below. So I fed the cable down and around the side to avoid that.

Lastly, that hole under the chasis does not quite align with the hole on the ESC mount. Have people managed to put a screw in there?

 

[DaniC]

Here's that servo in action!

 

[KnowAir]

Looking great!! Nice additions you've put on there! I don't know if I like the battery adapter, but they do work. I ended up using some 4mm threaded rod to replace the pins for the body tower support thingy..the o rings disappeared right quick.
Enjoy my friend

 

[DaniC]

Looking great!! Nice additions you've put on there! I don't know if I like the battery adapter, but they do work. I ended up using some 4mm threaded rod to replace the pins for the body tower support thingy..the o rings disappeared right quick.
Enjoy my friend

Yeah I don't like the battery adaptors either, but my two 4S batteries are Traxxas, a mistake I'll never make again.

 

[KnowAir]

Yeah I don't like the battery adaptors either, but my two 4S batteries are Traxxas, a mistake I'll never make again.

My brother has a pile of TRX batteries and chargers, as well as Spektrum..they are good IMO. Good run times and performance, but I can't stomach the price or the proprietary nature of their products..

 

[DaniC]

My brother has a pile of TRX batteries and chargers, as well as Spektrum..they are good IMO. Good run times and performance, but I can't stomach the price or the proprietary nature of their products..

Yes, and those TRX connectors are silly, I don't like how the cable is soldered in.

 

[KnowAir]

To put numbers on it, my brother and I both have bone stock xmaxx's. He runs the 6700mah TRX which cost $150 each. I run CNHL 6200mah @$50 each..he gets 5 more minutes run time..

 

[DaniC]

To put numbers on it, my brother and I both have bone stock xmaxx's. He runs the 6700mah TRX which cost $150 each. I run CNHL 6200mah @$50 each..he gets 5 more minutes run time..

Geez! 5 more minutes also means the probability of breaking something is a lot higher, which can potentially translate to higher running costs!

 

[BashingBrian]

@DaniC .. That servo looks awesome..!! I'm sad we don't get them over here, I might email them to see if they ship direct to the UK..

 

[KnowAir]

@DaniC .. That servo looks awesome..!! I'm sad we don't get them over here, I might email them to see if they ship direct to the UK..

Indeed! That thang is sexy I have looked long and hard at the ProModeler lineup.. I must agree if it's within one's budget, it's money well spent. This one's budget isn't included

 

[DaniC]

@DaniC .. That servo looks awesome..!! I'm sad we don't get them over here, I might email them to see if they ship direct to the UK..

They do ship direct yes. I asked them before. I just use the parcel forwarding service because they handle all the import paperwork and it's just easier.

Indeed! That thang is sexy I have looked long and hard at the ProModeler lineup.. I must agree if it's within one's budget, it's money well spent. This one's budget isn't included

Yeah, they're pricey, but they'll probably outlive everything else, including the truck itself!