The Maxx Project - Pt. 2

[smog]

It’s remarkable how well these old things clean up with some elbow grease. The electric conversions look like fun projects, I appreciate the novelty in what you are doing. There is no doubt that far and away the majority of what we see is simply following in the stream of what’s new and marketed. It’s refreshing to see unusual construction and creativity.

I have no real history in the world of stadium and monster trucks. My RC experience has two distinct periods . As a kid building Tamiya kits in the early 80’s, and as a father entertaining his kids post 2010. Now my kids are pretty much fully grown and I am left with it as a source of self entertainment. I occasionally have considered grabbing a stadium or monster truck as they seem to be the most available in local classifieds, but yeah everyone seems to think their vintage rc’s have great value around here. Must be the small population and supply. Of course the remoteness also makes have things shipped cost prohibitive. Perhaps I need to hit some garage sales...

Anyway keep the threads and posts coming. They are enjoyable

[OSRC]

Frankly, I'm kinda bored with solid axle trucks. I've built enough now that there's really nothing else to do with them. Something really revolutionary has to come out to get my attention nowadays. Until then, I'm always keeping my eye open for something to modify .... making something perform better out on the trail is a fun challenge!

You're not kidding about used RC prices, ouch. I used to buy and restore old Tamiya and Kyosho - not anymore.

[OSRC]

C-Maxx version 2.0 is finally done. Took the easy way out and just fudged on some Tamiya body mounts and dropped on an old T-Maxx body I've had for at least 18 years. I don't even know what it is....Proline Tundra I think. I found the window masks, but couldn't find the decals so I fudged some up. I went with the OG T-Maxx decal set for the throwback look. I freaking love it.



4WS in full effect. It never turned well, but this should make a ton of difference.


I know flex shots are passe, but I had to take one anyway. This truck has a ton of suspension.


I went out to do a test run in the backyard and plugged it in and nothing happened. O further inspection, apparently I stole the receiver for another project. Well, there's your problem! I dug out a new one and got it all set up.


It's geared a bit tall still for crawling duty, but it made for some fun bombing around. Amazed at how well a simple $20 Crawlmaster on 3S throws this chassis around. Definitely has plenty of power! I'll drop on a 14t pinion before heading out on a run.



Don't have much to crawl on in the backyard, but what I had it makes short work of.




Did some fine tuning on the steering and ride height and it's ready to go.

I've done a lot of custom builds, but this one is in the top 5 for sure. It's a mix of basher, crawler, and vintage with both nitro and electric overtones all in one lovable little gray fuzzball. Can't wait to get this back out in the woods.

[bgredjeep]

Very cool build. Any chance a standard 2.2 wheel can fit over the tmaxx knuckle? Maybe the lasernut wheels? I might have missed how tall the current tires are but it would look sick with some crawler tires.

Nice work

[OSRC]

Sure can, just barely. I thought about a 12mm hex conversion, or possibly SCX6 wheels and tires (which look excellent) but I like the fat 3.2 wheels. They are the essence of the Maxx trucks imo. Not to mention they have grip for days - that's a lot of contact patch!

[hnoroian]

I have an LST2 that I converted to brushless years ago. They are a blast to drive. And yes they do clean up nicely. Only problem is sometimes finding a-arms and bulkheads.

[OSRC]

I do have one I built to go fast too... Crawling is cool for sure, but it's a shame not using all that suspension.

[hnoroian]

Originally Posted by OSRC

I do have one I built to go fast too...

It fun to take it to the sand dunes and blast by people with +$100k 1:1s in the open and watching them try to catch up. They will almost always come over and talk about it.

[ktse]

C-maxx is awesome! I love everything about this.

I used to have the T-Maxx competitor, HPI Savage Nitro approaching 20 years ago while I was in high school. My buddy used to have a T-Maxx and we would terrorize construction yards jumping these things off the biggest dirt mounds we could find.

However once I started university, I didn't have time for RC cars, especially relatively high maintenance/time consuming nitro cars and took a 20 year break from the hobby.

Fast forward to end of 2021, another friend introduced me to the X-Maxx, it reminded me of my old Savage but bigger, heavier, and much faster. However as fun as it was jumping it off large objects, I was really more interested in finding out what it's limits were on crawling up trails and steep obstacles. We found out it far too punchy for slow speed handling and ended up launching it 30 feet down into a ravine. The experience piqued my curiosity and I ended up buying two crawlers last year.

Since that time, I have wondered what a fully independent suspension monster truck built for crawling would be like. The C-Maxx answers that question and I can't wait to see more developments on it.

Sent from my SM-G970W using Tapatalk

[OSRC]

First test run of the new chassis... sometimes it's a step forward, sometimes it's a step back.

The 4WS made all the difference in agility. It turns amazing now, and the 35kg servos proved more than enough. Interesting.



The new chassis does help with a bit more forward weight bias, but it's still geared a bit too high for finesse.



Lost 2 screws in the steering, so it had to call it a day early. I forgot to threadlock, so it was definitely an ID ten-T issue. The suspension though was a step backwards, it was way too soft and flexy. Plus, i have an issue with the hacked GTB radio - when switching from 2-4WS, the center point moves slightly on the rear wheels so it tracks sideways with 4WS on. I'll have to mess with the settings on the radio and see what I can do. It was enough to annoy me...I'm sure there's a solution there somewhere.

Not bad for a first run though...

[OSRC]

Did a bit of follow up work to the C-maxx. Went through the screws on the bottom of the chassis, countersunk everything, and rebuilt with threadlock. Nice and smooth on the bottom and no more lost screws


Dropped from a 17t down to a 13t pinion. Still not sure if that's low enough, but we'll see.


Found an old set of 1.5 CVD's in my stash, so I put them in back. The stock shafts have been a bit creaky, but nothing has broken yet. I have 2 more CVD's, but one is pretty bent, from back in my .26 big block days I guess.


Swapped in some 80wt to the shocks, and added longer rod ends for a bit more ride height. Ready for round 2!

[OSRC]

Testing V2, second run. Stole the tires for my Summit, so I swapped back to the prolines since they are a bit shorter and helped out with the overall gearing.. now it's definitely in crawler zone and excellent low speed resolution. Makes all the difference.


The only tuck I have than can bump up this rock. It's almost vertical, but the C-maxx pops right up there.


One of of my test rocks, it tests everything - down hill stability, turning, and climbing...


I come down the left side of the rock, make the turn at the bottom which is seriously off camber, and then climb back up the right side. Far right is a good climb, a bit more to the left is a bit more tricky since there's a significant lip at the top. All of my trucks take a turn on here, and it's not an easy line. Downhilled with stability aplomb, made the off camber turn due to the 4WS, and rolled right up both climbs. That puts it in pretty good company.



4WS changed this rig completely. it's now fairly agile, even with those big honking tires.


Excellent breakover.


I've already busted the rack up top.. I got cocky and did a hard roll and it shattered the roof rack. Oh well. Up the big test rock...pure test of climbing and grip. This truck does the same thing my other IS trucks do, it want to flip backwards on steep climbs. It's super stable to a point, and then flips pretty quick. I solved this on my Telluride by putting a diff in back with some silicone crammed in it. I'm wondering if that will help here too.


Getting to be leaf time... on the trails, this thing just eats. Everything! Big fat tires, decent clearance, and lots of torque goes a long way.


After almost 40 minutes of wheeling, I only used 24% of a 2200MAH 3S pack. Not bad! It's not that heavy, I have TRX4's that weigh much more. Kinda surprised it gets that good "mileage"


This is a 9" gap at least. I thought what the hell, and went for it. It has excellent approach and departure angles - those big front tires dropped in, clawed their way up the gap, and with a little bit of beans, the rears hopped right over. Very impressive! Did it a couple of times.


IS trucks sidehill like no one's business. This truck is no exception - it's like a spider sometimes the way I can turn on the side of a rock face and climb back up the side. COG is excellent, moving the battery down made a ton of difference.


Rocks, roots, doesn't matter. The C-maxx eats it up.


Finally nailed it - over the moon with this build...it's amazingly capable, and I'm not even sure what I'd change at this point (except the busted roof rack.) Might experiment with the rear diff a bit, it really made a difference on my 'pede crawler. Not sure it'll have the same effect with such big tires though. 4WS makes all the difference, it didn't turn for crap with just the front wheels but now it's decent. The driveshafts are probably going to need some beef - they make some cracking sounds here and there, but they are all holding up. I think the rear center shaft is going to be the first to bite the dust, but having said that those old maxx shafts are amazingly strong. I'm putting a lot of torque though some large grippy tires and I'm amazed they've held up this long. I'm thinking about tires... I love the look of the maxx tires - fits the truck perfectly, but this thing would be outstanding with some real crawler tires.

[OSRC]

First breakage! Took the C-maxx out and gave it a pretty good thrashing. Today's the first day I really felt grip was an issue, gigantic tires not withstanding. PL tires do NOT like cold weather, and today they were a bit on the stiff side. So I ended up rock bouncing a little bit and finally snapped a driveshaft.


Front left wheel got bound up against a rock and snapped the shaft - note the one wheel not turning. :( Figured that was coming eventually - Maxx shafts are tough, but not unbreakable. Beefed up parts on order!

[Gula]

FYI an ebay seller currently has the DYN7608 red aluminum steering upgrade for the 3906 emaxx

[OSRC]

Thanks Gula - was already gone by the time I checked it out - thanks for the heads up!

Speaking of, time for some more beef! I figured these axles were going to be an issue, so I had these on standby: Picked up some larger Maxx 3.3 shafts and knuckles a while ago from a chop shop and was just waiting for the stock plastic shafts to give up the ghost. Which they did!

Much, much beefier.


Narrowed slightly for the 1.5 Maxx arms and installed. Makes a huge difference! Does add about an inch of width though.


If these fail, I can try Summit CVD's which appear so far to be super strong. Or if I can swing it, MIP's and I'll never have to worry about it again.

[Gula]

https://www.ebay.com/itm/17590223132...mis&media=COPY This guy