Cross RC BC8 8x8 Build

[HumboldtEF]

Hi guys! New here... I’ve been contemplating making a huge purchase for a Xmas gift for my son so he and I can build away over winter break.
This is a great build thread so thanks.
I’m hoping you guys could recommend the top additions I should purchase so we don’t get stuck with needing things like the thin washer/shins you mentioned.
I see servo size is important as many don’t fit.

Do you mind giving me a short list of things to get for this kit like the small washers etc since you’ve had time to work out all the minor adjustments?
Thanks a million.

Well that sounds like an awesome gift. I hope he's old enough to appreciate it.
Disclaimer/warning If you purchase the parts I recommend below this will become a quite expensive project. Due to the weight of this rig you really shouldn't skimp on the electronics.

You need 2 strong servos the stronger the better. The spacing of the servo can be adjusted easily with some styrene or plastic scraps. I used the Savox 2290 which aren't cheap but they're about as strong as they come.

You'll also need a ESC, I would recommend the Castle Creations Mamba Monster X. You might need some wire and bullet connectors depending on how you wire the motor.

You'll need a receiver with lots of channels, how many? well that depends on how many of the features you end up using. I went for a 7 channel receiver which meant that I needed a new radio as well which also wasn't cheap.

The washers were just generic hardware store washers, just look back at my old posts for the specs.

to glue up the body you'll need some type of plastic cement like bondene (it melts and fused the parts, its not actually a glue)

I'm sure I'm forgetting a bunch of stuff though.

 

[Helijib]

Well that sounds like an awesome gift. I hope he's old enough to appreciate it.
Disclaimer/warning If you purchase the parts I recommend below this will become a quite expensive project. Due to the weight of this rig you really shouldn't skimp on the electronics.

You need 2 strong servos the stronger the better. The spacing of the servo can be adjusted easily with some styrene or plastic scraps. I used the Savox 2290 which aren't cheap but they're about as strong as they come.

You'll also need a ESC, I would recommend the Castle Creations Mamba Monster X. You might need some wire and bullet connectors depending on how you wire the motor.

You'll need a receiver with lots of channels, how many? well that depends on how many of the features you end up using. I went for a 7 channel receiver which meant that I needed a new radio as well which also wasn't cheap.

The washers were just generic hardware store washers, just look back at my old posts for the specs.

to glue up the body you'll need some type of plastic cement like bondene (it melts and fused the parts, its not actually a glue)

I'm sure I'm forgetting a bunch of stuff though.

Thank you so much. I'm on the fence as this is a huge purchase.
It sounds like an amazing rig but with a few shortcomings like lots of play in the axels and a ton of play in the tranny? And not really meant for rock crawling.
I have the Mamba X esc already so I'd be lucking out there. I was thinking 4 channel rx but sounds like that isn't enough. What are you running on all 7 channels?
Throttle, Steering, gear shifting, Lights? Winch?

I've read a few people are running this motor... do you recommend this?
https://holmeshobbies.com/motors/br...r-540-sensorless-rock-crawler-motor-1062.html

I'm really not familiar with bondene. If this machine rolls over will the cab crack or is it super durable?

Thanks for all the effort. We have been looking at 8X8 and 6X6 machines forever. If you have any other recommendations that would be awesome.

 

[HumboldtEF]

Honestly I didn’t want to explicitly talk you out of it but im not sure how much fun a kid would get out of the BC8 unless they really like the model and can drive like a adult. its not meant to be driven fast in not really meant to be a crawler, if it rolls major damage may occur (it weighs 20 lbs). Also whoever’s driving better be able to stop it if it rolls and that may be dangerous, ive never let mine just roll on its own i just don’t see it surviving a big tumble. it would be a fun project but im not sure the driving and ownership will deliver the same joy.

as for other recommendations I think its gonna be hard to beat the Traxxas 6x6, it’s should be fun, super durable more appropriate for a kid and much easier to maintain. though it does lack the build part of the equation.

I’ll have to double check what ive used on the rx later tonight.


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[Helijib]

Honestly I didn’t want to explicitly talk you out of it but im not sure how much fun a kid would get out of the BC8 unless they really like the model and can drive like a adult. its not meant to be driven fast in not really meant to be a crawler, if it rolls major damage may occur (it weighs 20 lbs). Also whoever’s driving better be able to stop it if it rolls and that may be dangerous, ive never let mine just roll on its own i just don’t see it surviving a big tumble. it would be a fun project but im not sure the driving and ownership will deliver the same joy.

as for other recommendations I think its gonna be hard to beat the Traxxas 6x6, it’s should be fun, super durable more appropriate for a kid and much easier to maintain. though it does lack the build part of the equation.

I’ll have to double check what ive used on the rx later tonight.


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Thanks, I totally hear ya. The build is what I'm after. My son can drive well. And is totally into scale performance, so slow will be good. BUT the roll over issue seems like it could be a disaster. If the body can't hold it's weight on a slow rollover that could be a problem! I understand it's a super detailed model but yikes, RC's tip over every so often. Any other recommendations would be great and appreciate your help!

 

[Helijib]

Would love to know what motor you all ended up going with in this rig? Not looking for speed by any means. Just power... power to climb and pull.
Appreciate the feedback.

 

[HumboldtEF]

Would love to know what motor you all ended up going with in this rig? Not looking for speed by any means. Just power... power to climb and pull.
Appreciate the feedback.

They do Include a motor with the kit which isn't bad, its a 560 sized motor. I ran that motor for a while before swapping. Just so I could put my own spin on it I installed a HH 550 Crawlmaster and its a decent match. Probably a bit undersized but I'm guessing even considering that since Holmes uses very strong magnets it might just have more torque and power that the stock motor.
I searched for a 560 sized motors but came up with zero made for crawling.

I have a friend who installed the HH Revolver 1000 KV, but I dont know If I'd want brushless power running through this thing. He mentioned it being a great fit with plenty of torque. Also 1800 kv is just too much it really needs the 1000 kv.

As for other 6x6's there's the new Axial which should be solid enough for a kid to run. RC4WD makes their Beast 6x6 and I only mention that because I think its probably one of the least appealing to me due to my experience with the brand. It looks like it might just be a stretched TF2 on coil springs (or maybe its closer to a Gelande 2?).

There's also the HG 6x6's, they look very nice and detailed, They seem to have a somewhat oddball design like the CrossRC's have (very complex design) when compared to mainstream RC crawlers. I have no experience with these though.

 

[Helijib]

Hi guys,
That’s for all the info a few weeks ago. I bit the bullet and bought the the BC8 and it’s been a great build with my son. We are at the point of adjusting the shifting servo and steering servos with some power. I have a new Castle Creations BEC 2.0 and have a question about how this would work with the BC8. I'd like to start off with the 2s power board the BC8 comes with. The new CC 2.0 waterproof BEC has two separate leads that in the Castle directions says to plug both leads into the RX. Bit of course this BC8 is a different beast so wondering how I use this nice Castle Creations Bec properly with this build? Or any BEC for that matter with the 2s and 3s boards.
Thanks so much with your time with this!!!

 

[Helijib]

Run into a few questions about the SK-1 sound kit.
Did you guys get a wiring diagram with your kit? I’m having a hard time figuring this wiring out with the board that the BC8 comes with. Any help would be great.
Thank very much!

 

[jaromir.mendl]

Hi guys,

That’s for all the info a few weeks ago. I bit the bullet and bought the the BC8 and it’s been a great build with my son. We are at the point of adjusting the shifting servo and steering servos with some power. I have a new Castle Creations BEC 2.0 and have a question about how this would work with the BC8. I'd like to start off with the 2s power board the BC8 comes with. The new CC 2.0 waterproof BEC has two separate leads that in the Castle directions says to plug both leads into the RX. Bit of course this BC8 is a different beast so wondering how I use this nice Castle Creations Bec properly with this build? Or any BEC for that matter with the 2s and 3s boards.

Thanks so much with your time with this!!!

here is wiring pic. for the BEC, important is to remove the red wire from the ESC if u are going to use the BEC(found it on internet but its working), for the rig i would recomend 3s battery, also dont forget to program the BEC to give the required power for the servos, it can be done by the castle link

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[HumboldtEF]

Hi guys,
That’s for all the info a few weeks ago. I bit the bullet and bought the the BC8 and it’s been a great build with my son. We are at the point of adjusting the shifting servo and steering servos with some power. I have a new Castle Creations BEC 2.0 and have a question about how this would work with the BC8. I'd like to start off with the 2s power board the BC8 comes with. The new CC 2.0 waterproof BEC has two separate leads that in the Castle directions says to plug both leads into the RX. Bit of course this BC8 is a different beast so wondering how I use this nice Castle Creations Bec properly with this build? Or any BEC for that matter with the 2s and 3s boards.
Thanks so much with your time with this!!!

personally I didnt trust running the voltage I run my servos at through all of the controllers and boards so I used a Bypass adapter. I used HH dual bypass adapter
https://holmeshobbies.com/electroni...iring-accessories/dual-rx-bypass-adapter.html

On that BEC you can plug one or both of the leads into the Receiver, the 2nd lead is how they get the extra amperage I believe. Anyway it works fine with 1 or both plugged in.

I think 2S is a good speed for this truck.

As for the sound kit there was a insert included with the sound kit wiring diagram. (you can ignore the notes I wrote on it)

 

[Helijib]

Thanks for both of those messages! Ours didn't come with that wiring diagram of the sound kit!!!! OMG... been puling my hair out but now all will be ok. Thanks for posting this, sure wish our would have come with that, it would have saved a lot of time! eeeek. Ours came with a duplicate insert of a wiring diagram for 2s and 3s setup.
Build is coming along well so far.

 

[HumboldtEF]

Yeah the wiring is one of the things I liked least about this build, its all over the place. I spent a few days staring at these inserts and searching for more info online (and finding nothing).

 

[Helijib]

Yeah the wiring is one of the things I liked least about this build, its all over the place. I spent a few days staring at these inserts and searching for more info online (and finding nothing).

I agree completely. A huge thanks to you guys for helping out with missing info.
Really appreciate it.

 

[HumboldtEF]

No problem happy to help!

 

[jebster]

So I finally picked one of these up. I'm in the build process but had a question. What paint did you use for the tail light and blinker lens covers? I want to get the red and yellow colors but wasn't sure of the type or brand that would work best.

 

[HumboldtEF]

So I finally picked one of these up. I'm in the build process but had a question. What paint did you use for the tail light and blinker lens covers? I want to get the red and yellow colors but wasn't sure of the type or brand that would work best.

Sorry I just noticed your question. I have good luck with Tamiya TS paints (for hard bodies not lexan), clear red TS-74 and clear orange TS-73.


Sometimes it takes many coats to get the red to be less on the pink side. One thing that helps in this regard is to paint both the inside and outside of the lens. Also worth noting, you cant really put a heavy coat on with these paints, just stick to many thin coats.



I just did these blinkers on Friday, about 3 coats on each side (inside and outside).

My method for holding these in place while painting is to put some painters tape on a box with the sticky side up (but stuck to the box as well) then just stick the lenses to it. When you're ready to flip it just stick it to the same spot.

 

[jebster]

Thanks for the response and all the advice. I'll be getting those paints to do mine because it looks like yours came out nice.

Sorry I just noticed your question. I have good luck with Tamiya TS paints (for hard bodies not lexan), clear red TS-74 and clear orange TS-73.


Sometimes it takes many coats to get the red to be less on the pink side. One thing that helps in this regard is to paint both the inside and outside of the lens. Also worth noting, you cant really put a heavy coat on with these paints, just stick to many thin coats.



I just did these blinkers on Friday, about 3 coats on each side (inside and outside).

My method for holding these in place while painting is to put some painters tape on a box with the sticky side up (but stuck to the box as well) then just stick the lenses to it. When you're ready to flip it just stick it to the same spot.

 

[jebster]

By the way, did you ever get the sound system to work? I think I have the same issue you had where I can get the horn to sound and the startup/idle but no throttle response.

 

[HumboldtEF]

By the way, did you ever get the sound system to work? I think I have the same issue you had where I can get the horn to sound and the startup/idle but no throttle response.

No I never got it to work on throttle inputs, I just gave up. The actual motor is so loud that its hard to tell if the sound kit is working but I'm pretty sure it does not throttle up (it just idles).

 

[jebster]

No I never got it to work on throttle inputs, I just gave up. The actual motor is so loud that its hard to tell if the sound kit is working but I'm pretty sure it does not throttle up (it just idles).

Ok. I might reach out to see if cross-RC has a suggestion. Although they never responded to my message about the kit missing half of a specific size of screws so I'm not sure how good there customer service is.