HumboldtEF's Evolving TRX-4

[HumboldtEF]

Well I just cant keep my grubby little mitts off of my "completed rigs". I just won one of the new Crawler Innovations TRX-4 Electronics trays that was given away on RCCrawler last week which has spurred me on to do something I wish I had done originally (though they weren't available yet). (Thanks again CI "thumbsup")

I pulled off my homemade front bumper with SSD ox winch, It was nice and heavy but didn't provide the best approach angle.

I picked up a KMS K3 servo winch to make up for removing the heavy front bumper and winch, but its not close to making up the weight lost, although by relocating some electronics to the tray it may have at least shifted the weight forward.

I got started with the SSD front bumper, I really love how simple it is "thumbsup"
I decided if I was going though another evolution that I'd try to get the best approach angle that I could so I flipped the front bumper mount upside down.

Here's the bumper after i cut off the lexan flush with the bottom of the headlight buckets

Not as tight and high as it could be (before flipping the mount)

Bumper mount oriented normal

Flipped/upside down

Flipping the mount raises the bumper 5/16"/8MM. In order to make room for the higher bumper I cut out the lowest row on the radiator grill. A large pair of scissors worked amazingly well for this, though I did need to squeeze very hard also holding them from outside the handle gave a bit more leverage. I just held it tight to the top of this lower row while I cut. I honestly don't think I could have done better with other tools, was a bit surprising.

The radiator grill now has a little step up from the lights which the bumper can now tuck under and be pulled inwards as well.

It should have enough room around it that it wont be rattling on the bumper as I drive, but its gonna hit on rolls and tumbles.

the approach angle is pretty damn awesome now "thumbsup" maybe 80 degrees or so.

I'm still wiring up the new servo winch and figuring our wire management so up at the electronics tray its a bit of a rats nest at the moment. I was able to cram everything but the receiver up there. Its got a KMS K3 servo winch, the Traxxas light controller, CC 10 amp BEC, Holmes ESC, the winch controller (mounted on top of the servo winch)

I may not have been paying the closest attention when I unhooked my winch controller so I'm troubleshooting why its not working. I brought it to work to kill some time this morning but didn't have anything on hand to help me figure it out, but I have a feeling I have swapped the inputs and outputs Hopefully I haven't done any damage.

I also started drilling holes in a few parts to reduce weight were strength isn't as important. I also cut off the portion of the body posts that hang below the mount. Even without the cross brace these towers are roughly 100% stronger than SCX10 shock towers (man those are flimsy) so they'll be fine.

I'm still waiting on a fairlead to put on the front bumper, which I believe SVT923 did first, thanks for the Idea!


I've also done a lot along the way to get here so I'll be going back through the forum to find any useful posts to add here.

 

[Teng]

Well done and Subscribed [emoji1320][emoji106]


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Nice work on your front bumper should be very helpful on steep hill [emoji106]


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[HumboldtEF]

Nice work on your front bumper should be very helpful on steep hill [emoji106]


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Thanks, it was a helpful bit of ballast. Though I did drag it quite often, well just like stock bumper clearance wise I guess. But now its been replaced with a much lighter aluminium bumper from SSD. I'm trying to get the weight back up front though.

I figured out the issue I was having with my winch. One of the leads on the winch controller board had broken loose but being coated in plasti dip made it hard to notice. This lead has broken loose before, I may have got a dirty solder with all the plasti dip around it.

I've also got a full set of MFR portal covers which Ive treated with Brass Black which tarnishes or darkens the brass.

If you do this use gloves and maybe a mask, its nasty stuff.

I used cotton swabs to hold the brass black liquid in place as surface tension tends to make liquid pool up and pull away from sharp edges. The brass black worked best if I had just dipped the cotton swab, after it had reacted with the metal it stopped working as good as the fresh swabs. This process took a while due to the many contours of the covers.
I left the inside alone so it doesn't react with the bearings.

I left the wet swabs on overnight thinking it would help but it just made it spotty, I don't recommend that.

I did this treatment to match the Codyboy Designs portal weights which I also treated (I just have 1 set up front)

 

[Levi]

Looks like you got a good project going on. I notice the holmes hobbies goodies you have and mentioned. How do you like the hh stuff? Any thoughts or comments about it? Hh seems to be great stuff from what I gather.

 

[HumboldtEF]

Looks like you got a good project going on. I notice the holmes hobbies goodies you have and mentioned. How do you like the hh stuff? Any thoughts or comments about it? Hh seems to be great stuff from what I gather.

Thanks

I do love the Holmes Hobbies motors and their ESC's though the ESC is just a tweaked Castle Creations ESC (I think they add the Holmes Hold and silent mode). I think the only place they fall short is their older servos, they just revised the SHV500 (V2) so it might be better now, but I've broken quite a few center pins on their V1. I picked up a new V2 servo and so far so good.

 

[Levi]

Thanks

I do love the Holmes Hobbies motors and their ESC's though the ESC is just a tweaked Castle Creations ESC (I think they add the Holmes Hold and silent mode). I think the only place they fall short is their older servos, they just revised the SHV500 (V2) so it might be better now, but I've broken quite a few center pins on their V1. I picked up a new V2 servo and so far so good.

Good to know thanks. I've been eyeing out the hh motor for another project and debating on which to use. I'd have to agree the hh esc is a copy of castle pretty much.

 

[HumboldtEF]

So I've driven the new configuration a few times and I've upset the balance a bit up front, not enough weight has been put back. I'm still not ready to give up on the heavy body though. I really like the improved approach angle with the SSD front bumper.

I did undo the preload all the way on the springs to get it hunkered down more, maybe having the rear this soft is allowing it to flip backwards easier?

I've also run into some interference with my wireless winch controller, it works but is glitching on and off based on how far away my remote is. If its 6"-8" away it works fine, but as it gets farther away it starts to glitch. I tried to put some caps on the winch motor with no luck, I disconnected the wires from the main motor and it still had interference. I moved the controller as far away as I could also with no effect.
I'm not sure I can do anything about it. Although I did hear that HeyOk is coming out with a revised wireless winch controller ( I hope I'm not spilling the beans here) which is a bit smaller. I'm gonna pick one up in hopes that it will be more reliable.

 

[rockhugger]

I added pre load to mine and noticed improved crawl characterics. Agree that it would want to roll backwards with less pre load. It's heavy and has a lot of torque so it needs extra support at the shocks. I wish they would release option springs with higher rates

 

[ScoJac]

I wish they would release option springs with higher rates

They have them, 4 optional rates. I seen them in the accessories section a couple weeks ago.
$6.00 a pair


Standard spring rates
no stripe .45
green stripe .54

Option spring rates
yellow stripe .22
white stripe .30
orange stripe .39
blue stripe .61

 

[HumboldtEF]

They have them, 4 optional rates. I seen them in the accessories section a couple weeks ago.
$6.00 a pair


Standard spring rates
no stripe .45
green stripe .54

Option spring rates
yellow stripe .22
white stripe .30
orange stripe .39
blue stripe .61

Thanks, I had tried out some Ascender springs but need to go even stiffer.

 

[svt923]

I'm still waiting on a fairlead to put on the front bumper, which I believe SVT923 did first, thanks for the Idea!

I'm glad my bad influence is affecting others. :mrgreen:

 

[HumboldtEF]

I keep meaning to update this thread. I gave the Defender body a bit of a face lift and shaved off some weight here and there and I just installed the Holmes Hobbies 1800 KV Revolver motor paired with a Sidewinder 4 ESC.

Its a very unique motor for sure definitely diesel like as JRH has described, it dosnt bog down as easily and because of that carries momentum very nicely. The noise is not as bad as I expected (I think videos dont do them justice) though I plan to limit late night use to avoid annoying the neighbors. Dialing in a gentle throttle curve got me a nice slow start up, along with setting start up power to high and timing to 0. I ended up dropping from a 11T to a 9T pinion (running on 3S) and I'm happy with being able to crawl and hill climb in 1st gear so it has a nice slow speed but enough headroom (wheelspeed) to still climb.
I think the 1400KV motor would be a good fit too and it would give you more room to play with gearing, right now I'm at the lower limit.

The drag bake on the Revolver is super strong and I ended up turning it down to 5% as I like it to roll down hill ever so slightly rather than lock up the wheels especially with this front/top heavy rig. Having the drag brake set there really makes this motor feel different because when you let off the throttle (when you're giving it a trigger full) it takes a second for the wheels to stop spinning instead of just instantly stopping like is typical. I handed off my controller to my brother to show him this and it only took one try for him to notice the difference. I think its kind of cool and a bit more like a 1:1, but again this is probably down to my drag brake setting.

I'll put some pics up later tonight of the body mods but the inspiration came one night in the middle of watching a youtube video with a heavily modded Defender that was turned into a truggy, I immediately picked up some scissors and started trimming up my body. I wasn't copying what they had done just inspired to do something a bit different.

Fender flares were cut with scissors

I reminds me of someone hiking up their dress when I look at the rear

That got me started on pulling apart everything I could on the body looking for areas I could shave weight. I pulled off the roof rack which I had tried before but didn't like how the body would rattle against the bumper now that the support this roof rack provided was no longer there. This time I took a few extra steps after removing the roof rack, I dropped down the body mount posts so they only stuck up as much as needed (they pop up higher to go through the roof rack) and I cut 2 lengths or rubber hose to go around the body posts that provide support below the body pins. I also did a mod that was mentioned to me by Rockhugger where he took out the center sections of the exocage and trimmed off any excess in order to get the cage tight up against the body, I found the top pieces were 7/32 too long and the font cross piece under the windshield was around 3/16 long. I measured these but loosening one end and pushing it past the other end so I could check how much tighter I could get them. Take that measurement divide by 2 and thats how much you cut off each end. After tightening up the cage the rattling was reduced quite a lot, it still rattles on big bumps but it something I can live with now. I also like the look of the tighter cage.

I took off the front and rear inner fender supports and basically hit it with some buckshot (drilled tons of holes) leaving support where needed. I also shaved off the top of the front support because it contacts the under side of the hood and was taking off some paint, I had previously put some gorilla tape in between them but cutting it down is a better solution I think.

I also hollowed the first aid kit and gas cans out as much as I could

I trimmed up the fender flares and I cut off the step on the sliders so all thats left is what the bottom of the body slots into.

 

[niro750]

Nice work, how much weight did the body mods save?

 

[Shinchu]

Very nice Casey! I think you might have convinced me I need a brushless rig haha
You think that can would play nice inside a scale motor cover? Asking for a friend...
I like how you described the softer drag brake. Makes a ton of sense.
Great work on the body too!
One of these days I will build something NOT a tribute so I have a little more freedom... Well Andrews Chevy I guess.
Nice work! Hope to see it again at proline by the fire 2019!!!

 

[rockhugger]

Nice Casey, that tighter cage looks awesome, and something so subtle has a big effect on the truck. Not only does it eliminate rattles, but now you can squeeze through tighter crawl spaces by (............) that much "thumbsup".

I started lightening my cross members by way of shot gun method, but eventually just took the side cutters to them and removed big chunks of material, I think my total loss just in C-members was 14'ish grams, and they are still doing the job traxxas intended them to do.

I can post pics of the before and after if you like... I don't want to polute your thread before checking. "thumbsup"

 

[HumboldtEF]

Nice work, how much weight did the body mods save?

Well for once I decided not to weigh anything like I usually do. Instead of looking at numbers and deciding I should shave off more i decided to just take off as much as possible with the blinders on so to speak.


I recall weighing it with the old heavy steel front bumper and it was 9 1/2 ish lbs. I just checked and now its at 8 lb 14 oz and most of that weight was up high so it really feels better at steep climbs and side hilling, just the body weighs 1 lb 7.4 oz. This weight "shavings" has really reinvigorated my interest in this rig.

Very nice Casey! I think you might have convinced me I need a brushless rig haha
You think that can would play nice inside a scale motor cover? Asking for a friend...
I like how you described the softer drag brake. Makes a ton of sense.
Great work on the body too!
One of these days I will build something NOT a tribute so I have a little more freedom... Well Andrews Chevy I guess.
Nice work! Hope to see it again at proline by the fire 2019!!!

Thanks!
I'm a brushed motor fan deep down but I do like the Holmes brushless motors too and the revolver has to be the closest you can get to a brushed feel. Just be warned though they will lead to bashing, with great wheelspeed comes great responsibility lol. The number of roll overs since installing this motor has skyrocketed.


I considered putting this in my Land Cruiser which has a scale motor cover and i dont think it would end well. Scale motor covers slide over the RC motors with a tight fit, in fact this is what holds them in place. So if the motor itself spins so does the 3D printed motor. I suppose one could print a larger version or one with a larger opening but that would be a tricky balancing act. the other thing is it would insulate the noise from the motor and depending on your viewpoint could be good or bad.



Yeah throwing out the rule book is really freeing.


I hope to make it to PLBTF next year too, is like a 14 hour drive but well worth it.

Nice Casey, that tighter cage looks awesome, and something so subtle has a big effect on the truck. Not only does it eliminate rattles, but now you can squeeze through tighter crawl spaces by (............) that much .

I started lightening my cross members by way of shot gun method, but eventually just took the side cutters to them and removed big chunks of material, I think my total loss just in C-members was 14'ish grams, and they are still doing the job traxxas intended them to do.

I can post pics of the before and after if you like... I don't want to polute your thread before checking.

Yeah thanks for passing along that tip on tightening the cage up "thumbsup" I haven't found the right spots to squeeze though yet but I believe it.

I'm interested to see what you did to your crossmembers, please post up pics when you get a chance.

 

[HumboldtEF]

I just wanted to link a few other things that should have gone in this thread and to make it easier to find. I also added some older posts on the truck.

I added a bunch of 3D printed goodies here http://www.rccrawler.com/forum/traxxas-trx-4/587920-3d-printed-goodies-trx-4-a.html

This was copied from the Mods thread:

First mod, smaller black body clips from an Axial Yeti, they fit better/dont rattle and dont stick out as much as the chrome

Magnets to hold on to the body clips

Theres a nice spot to hide a magnet under the top of the roof rack, not visible when assembled

Custom front bumper with winch mount. theres plenty of weight up front now, made from 1/8" thick steel

Custom rear bumper, this seems to be about the most clearance you can get without cutting the body. Its a bit thin but it is braced on the back side

I was able to retain the 2 locating holes that the back of the body uses, I had to trim the plastic post a bit so they dont stick out

I simplified the rear gate, I removed the spare tire and cut its mount as well as the gas tank mount free and bolted the tanks in front of the hole left after I cut off the spare tire mount.

Another simple mod, snorkel dress up using a crawler innovations sticker and an old speaker grill.

Sticker

One old speaker grill that I've repurposed once already

I used scissors to cut the shape out which was much cleaner than a Dremel, no filing needed. On the raw metal edge I used permanent marker to color it in.

CA wood glue (non whiting) I put a dab in a little plastic container and used a skewer to apply a tiny bit on each corner once I had it lined up. Its just glued to the sticker (hopefully lol)

I tried to make it smaller than the end of the snorkel so its inset all around, hopefully it wont cut me.

 

[niro750]

Nice work