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TBuggy builds a TRX-4

TBuggy

Pebble Pounder
Joined
Dec 20, 2020
Messages
113
Location
Seattle
I wanted to start a thread for my first crawler. It won't be a complete build thread as there are plenty of those already. I did want to post/log the build though as it progresses, as far as updates, upgrades, and once complete driving experiences.

So far, collecting parts has taken me quite some time since I was being patient and waiting for things to be in stock and only getting things a little bit at a time.

I have been scouring youtube and this site for info on TRX-4 builds and that's how I decided how I was going to build this TRX-4.

So far parts I have picked out for this build are as follows;
-Yeah racing front and rear axles
-Yeah racing rear inner portals
-Yeah racing lower shock retainers
-Treal brass lower link mounts
-Vanquish SS links (I will probably only be using the lower links)
-TRC brass rear outer portal cover
-no name brass front diff cover
-HR offset steering link
-no name aluminum upper shock mounts
-Bow house LCG battery tray
-Samix bras c hubs
-Samix brass front inner portal
-SSD portal covers
-Junfac steel drive shafts

Electronics at the moment;
-HH Expert CrawlMaster 27t
-Reef's RC Tripple 5
-Spektrum 2 in 1 ESC/reciever

Wheels are boom racing with stock tires for now. I will look in to different tires later down the road I am sure.

I plan to run the stock body for now but eventually was thinking of getting a half cab body simply because I like that look.

Still in the process of putting things together but have come to a small hang up that I know I can fix, but would like to know if anyone else noticed the same thing and how did they deal with it?

Here's where I am at so far,
https://flic.kr/p/2kqEwJr
https://flic.kr/p/2kqAeqC

Love these outer portal covers...I had to get them because they have my initials on them! LOL
https://flic.kr/p/2kqBtEv

Now about one of the issue I am having, I went to install the servo and the realized the mounting holes do not line up? I am using a reef's triple 5 and I have heard this as being a suggested servo from some, but didn't see a mention of the servo not fitting perfectly.

Picture of the issue;
https://flic.kr/p/2kqBYWs

Second issue is the yeah racing spring retainers...does anyone else have experience with these? It appears I will have to file/sand down the outer dimensions of the shock mount so it will slide into place. I have not done this yet and wanted to wait until I heard from anyone else that has run into this. They should be able to slide down the mount about another 5mm based on the stock version and looking at the recess in the retainer itself.
https://flic.kr/p/2kqE28b

Thanks for all the help and info I have been able to find here I think I am well on my way to having my first crawler!
 
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That is quite the list of upgrade parts. I generally encourage first time drivers to get a feel for the truck in it's stock configuration before buying a bunch of parts that may or may not be an improvement.
 
That is quite the list of upgrade parts. I generally encourage first time drivers to get a feel for the truck in it's stock configuration before buying a bunch of parts that may or may not be an improvement.

I do agree and usually thats what I would do. I admit I went a little overboard but thats part of the fun, right!?

I actually plan on getting a TRX4 sport rtr also and keep that one almost all stock. I will get a good first hand comparison.
 
I figured out the picture thing! I didn't like posting a link and wanted to post the pic right on the thread like everyone else does. Just need to figure out how to make them a little smaller now LOL.

IMG_2512 by T Buggy, on Flickr

IMG_2510 by T Buggy, on Flickr


I pretty much have the truck built now. I am waiting on an ESC, I decided to go with the go to HW 1080 since it will be able to apply more voltage to the servo. I have never needed to use a BEC on an RC before so are there suggestions on which one I should get or do I even need one?

Also think it needs some lights now!

Thanks!
 
Just noticed you started a build thread. Congrats on getting the TRX-4! It’s a great rig to start with!

Nice upgrade list! Looks like it’s going to be bomb proof!

My Sport is basically built like yours. Built tough and ready for battle![emoji3]

I normally do not run a BEC. I’m running a Mamba X in my sport so no BEC needed. On my other rigs that are using the HW 1080, I’m just using the internal BEC and haven’t had much issue. It will depend on tire size and strength of servo if you’ll need to add one.


Sent from my iPhone using Tapatalk
 
OP,

Did you get your servo mounting issue figured out?

My Holmes and G13 both had the same issues as your having.

I filed out the passenger side mounting holes and kept the driver sides holes intact.

9828cce2cfc7d170fff5b3ced33e35a9.jpg



Mount the drivers side first then put then put the passenger side screws in the stock location servo mount holes. The screws now fit in the area you filed out.

Works just fine.

A popular RC YouTuber did this same trick when mounting a Reefs on a Trx4 I believe. He also said this would work just fine. That’s where I found this solution when I encountered this problem.

I see you’re running stock tires. The Canyon Trails are a very capable stock tire and even more so with a little modding.

I cut the lugs on mine with a dremel and trimmed the little tread on the center lug.

d82760288e19076176920b683f2b6510.jpg


I only had enough ambition to clip the outside little center lug. Lol. The rest are on my to do list. Modding stock tires is a messy tedious job but it’s free. My modded CTs do not hold me back on my slick granite rocks when compared to my Predator Hyrax and J Concepts Landmines.


Boy you got after this right off the bat!!! You’re not playing around!

Looks good!

Looking forward to see how it does out there. [emoji106]
 
OP,

Did you get your servo mounting issue figured out?

My Holmes and G13 both had the same issues as your having.

I filed out the passenger side mounting holes and kept the driver sides holes intact.

9828cce2cfc7d170fff5b3ced33e35a9.jpg



Mount the drivers side first then put then put the passenger side screws in the stock location servo mount holes. The screws now fit in the area you filed out.

Works just fine.

A popular RC YouTuber did this same trick when mounting a Reefs on a Trx4 I believe. He also said this would work just fine. That’s where I found this solution when I encountered this problem.

I see you’re running stock tires. The Canyon Trails are a very capable stock tire and even more so with a little modding.

I cut the lugs on mine with a dremel and trimmed the little tread on the center lug.

d82760288e19076176920b683f2b6510.jpg


I only had enough ambition to clip the outside little center lug. Lol. The rest are on my to do list. Modding stock tires is a messy tedious job but it’s free. My modded CTs do not hold me back on my slick granite rocks when compared to my Predator Hyrax and J Concepts Landmines.


Boy you got after this right off the bat!!! You’re not playing around!

Looks good!

Looking forward to see how it does out there. [emoji106]

Thank you for the reply!

Yes I did figure out the servo issue and ended up doing exactly what you just said to do. It really seemed to be the easiest and most logical solution. Its funny that the dimensions aren't standard on these size servos.

I had been wanting to build a crawler for some time now and finally decided to just jump in with both feet!

Thats good info on how to mod the stock tires. I will definitely keep that thought in mind.
 
Slowly but surely I am getting this thing closer and closer to its first run. I know I can just get everything running as is but I just picked up a CC BEC and wanted to make sure I hook it up correctly. i have seen several diagrams plus the one that is included with the unit. But still am not sure what the best way to hook it up is?

This is the BEC i picked up; https://www.castlecreations.com/en/accessories-5/cc-bec-010-0004-00

I have seen some people use a harness like this https://holmeshobbies.com/electroni...ssories/holmes-hobbies-rx-bypass-adapter.html I do have all the necessary parts to make one of these harnesses if this is the preferred way to hook things up. I wasn't sure if this was just used when you don't have enough ports or if its just a better way for one reason or another.

And then another diagram like this without a harness; http://www.rccrawler.com/forum/electronics/563314-cc-bec-spektrum-rx-issue.html

I am running a Spectrum DX4r pro https://www.horizonhobby.com/produc...CgOd-tldAvYRVX4awRC_ZtwC_R95ybbBoCzu8QAvD_BwE

Any advice is welcome and appreciated. I just don't want to hook things up and ruin something. This is my first BEC I have installed, I never felt the need to upgrade the ESC internal bec with any of my racing buggies. I guess the biggest part that confuses me is, I am not sure if it matters which port the BEC is plugged into?

My next question is when I go to make adjustments via castle link card I just keep the BEC powered by the battery and then plug straight into card correct?
 
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My servo is direct powered but this is my interpretation of the harness diagram.

8806d242a4f104ebba8fc6c315a1b397.jpg


Connector that says servo plugs directly into the servo and connector that says bec plugs into bec, then rx servo plugs into appropriate channel on receiver.

I want to say the benefit of using this harness is that you are not putting voltage to the receiver. I guess some receivers only handle up to x volts and with the bec putting out more than what the receiver is rated for, it can smoke the receiver. I think.

If I’m way off, I’m pretty sure someone will chime in and right the ship. Lol
 
Well now I found out (I guess I should have read a little more) that the CC BEC cannot be adjusted without a PC....lame I do not have a PC or windows.

Thanks for the reply again Benp, much appreciated!
I think the harness will be the way to go when I get the BEC programming figured out.

For now I guess I will run it as it is, cause I am getting a little anxious to try this truck out.
 
I wonder if it’s adjustable with the Bluetooth castle link?

I thought that was the ticket for a second and looked into that, but apparently this is the only CC BEC that is not adjustable via bluetooth. :cry:
 
Did a couple quick test runs the other day. I thought it handled very nice for a first run!
<iframe width="560" height="315" src="https://www.youtube.com/embed/ERE22KWqTPk" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
 
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Another quick video.
<iframe width="560" height="315" src="https://www.youtube.com/embed/SDHauRH7C80" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
 
<iframe width="560" height="315" src="https://www.youtube.com/embed/Q5bFVgYDkIo" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
 
Looks good!

That looks like a fun spot!

I’m jealous of you guys being able to wheel in January.
 
Did some work on the backyard course. One of the first runs, its been wet so rocks are slippery!
<iframe width="560" height="315" src="https://www.youtube.com/embed/Q8tNKVU6dG4" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
 
Did some work on the backyard course. One of the first runs, its been wet so rocks are slippery!


I love it!!!

Absolutely perfect that your course is part of the landscaping! It blends right in.

Looks like it’s a blast!!

ETA - Again, a bit jealous of you guys that are able to wheel in January. [emoji106]
 
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