My Micro-t to Micro High Roller to Micro Desert Truck.

[olds97_lss]

I have a myriad of threads for this, but nothing cohesive that has the full history of it. So I thought I'd take what I could from my original FrankenMicro thread and put it here as a starting point.
https://www.rctalk.com/forum/threads/frankenmicro.65264/

Updated original post image links and reposted here as I can't edit the original post from 2008:

Well, in leu of buying a longer DT chassis, I figured I'd futz around a bit with some light gauge steel and my micro-t. I added about an inch to it's length between the esc and rear shock tower.

I did this primarily so I could run micro raminator tires on it with an AAA saddle pack that I made. She won't win any beauty contests, but it sure runs a long time and is fast! May need to upgrade the shocks to some that have oil as I understand they are a bit stiffer and don't do a lot on the stocker. With the added weight mine has, I'm sure they will compress.

Anyway, poke fun if you wish. I enjoyed working on it though. Made it handle jumps a lot better and pretty much killed my wheelie problem. It takes off at WOT now in a straight line and really cooks.

The original with AAA's:

The raminators on the rear:

The extension plate:

A brace on top to keep it from bending on landings:

And for the concourse, really butchered body:

Looks ok from the front though, this is what the cat will see coming at it!

I forgot and left it on last night, so the battery is dead... charging now, I'll try to run a full pack through it to see how long it lasts. Best guess so far is 30+ minutes of cat chasing.

Upgrades:
axles with nuts
bearings all around
Atomic II motor with bearings
ziptie front tierods
raminator tires/wheels

Video from second post:

 

[olds97_lss]

I then converted it to a high-roller. I stuck with the AAA cells, just reconfigured them to be a flat 4xAAA pack, modified the battery bay area to fit the esc/receiver like I did on the micro-t chassis so the pack could just lay on the flat top part of it.

Also made little risers for the rear to make it stand a bit taller:

 

[olds97_lss]

Since I had the 2.4ghz brushed/brushless board that had a normal 3 wire servo plug, I modified it a bit to fit a micro traxxas servo I had in it.

Also made a servo horn to fit the servo, which removed the servo saver:

I also replaced the fixed steering links and upper a-arm links with micro ball ends:

I later rebuilt the oil filled shocks and put on appropriate springs so they would actually function and ditched the 4xAAA pack and started running a 2S lipo. To keep the shocks from leaking on me, I turned them upside down. They have worked fine for a year like that.

Somewhere in the middle I replaced the trans case with a hot racing one that used a bearing on the input shaft. I also did the MSCT diff mod so it had a more robust diff in it. Odd that I don't have any photo's of that...

 

[olds97_lss]

I recently tried putting the brushless motor from my MSCT in it (since I never drive that in the house, too large/fast). I ran it for a bit, but didn't care for it. It lacked bottom end torque and I wasn't able to finda lower kv motor to try and use, so I went back to the DT motor.

Then we recently got a new kitten who was really interested in the truck. The previous cat's would wander after it for a few minutes, then just go somewhere high and watch it. This new cat chases it like it's a mortal enemy the entire time it's running.

With that in mind, the High Roller was just too tippy in the corners to outrun her. So I found a DT chassis still available and moved everything over to it. I must have pinched a wire or something because when I turned it on to test everything, steering worked fine, forward worked fine, reverse didn't do anything and after about a second, it blew out a fet and desoldered the negative motor wire from the board...

I spent many hours online trying to find a replacement and came up empty. Then I noticed the fet's all appeared to be the same, 4502GM and I started trying to find a replacement. The only one I found was in China via ebay, so I ordered 3 for $9 and figured I'd try replacing it in 5 weeks when it shows up... if it shows up. The next day I was digging through my spare parts and found the original AM brushed board. It had 2 of the same fet's on it. Since I threw away the AM radio long ago (it was so glitchy), I decided to try and transplant one of the chips. After an hour of tedious desoldering and resoldering using tweezers and a magnifying glass... this was as good as it got:

Wired it up on the bench and tried it. It powered on, steering worked, forward worked... no reverse or brake. Back to the internet...

 

[olds97_lss]

Found a cheap brushed 20A esc on amazon, 2 for $16, figured it was worth a try.

From my other thread asking anyone if they new of an alternative:
https://www.rctalk.com/forum/thread...d-losb9524-or-alternative-for-brushed.129761/

They showed up and I spent the better part of 5 hours installing it and an old orange dsm2 receiver inside the battery bay of the micro-DT chassis.

Seems the esc doesn't have brake. There was a switch on it that allowed for braking, but I removed it and jumpered the leads assuming it was either forward/brake or forward/reverse, the switch had 2 positions. I should have tried both settings to see what it did before installing it, don't know why I didn't. Perhaps the other setting makes it do forward/reverse and brake. It came with 2 of them, so I could wire up the second one on the bench to see what it does.

The esc:
Readytosky RC 20A Brush ESC Motor Speed Controller w/Brake for RC Car Boat Tank(2PCS)
https://www.amazon.com/gp/product/B086LDK6LD

I shortened the servo lead by a bit more than half so I didn't have so much extra to try to cram in there with it.

I ran across a 30A version too, but it's longer. Not sure it would have fit.

I put a new hole in the MHR body, made a body post out of a piece of a probodyrc body for the rear and left the MHR front body mount as it was. It's at a goofy angle now, but it still works.

Also, the spur is for the micro-crawler. I had that on there to slow it down and add some bottom end torque when running the DT or raminator tires. It doesn't fit inside the spur cover though. It didn't on the high roller either, but I sanded it with a sanding drum on my dremel until the inside wall was paper thin all around the spur, then it fit. May do the same with the standard cover to help keep hair/fuzz from getting all wound up in the spur.

Finished product:

Only ran about 1/3 of a pack through it tonight. Will try and run a full pack through it this week to see how the esc does. I did cut away the heat shrink around the larger fets so they could breath a little bit better. Isn't a ton better since I have it jammed in the battery area, but still they aren't wrapped with a thick heat shrink anymore, so it couldn't hurt.

I removed the esc and changed the jumper (used to be a 2 position switch that I somehow already lost) to see what the other setting did. It does have brake, but it's forward/reverse/brake. The brake is so weak that it's useless even on a micro-t. It barely slows it down and I repeatedly smashed into everything in my path. I took it apart and put it back to forward/reverse. Isn't the easiest to control, but at least I smash into less stuff.

If I didn't have the MSCT diff internal mod I did many years go, the forward/reverse slamming would likely fry the diff. But as it is with the DT tires on it, they just do a reverse burnout if I go too far in reverse. I changed my radio EPA to make things a bit more controlled to 70% fwd 25% reverse. I have the old atomik BB motor in it and I'm running it on 2S.

I also was able to dremel out the inside of the spur cover enough to get it to fit over the larger spur.

My small 2S packs are really old and after running 2 packs through it, it didn't seem to overheat or have any issues. The only notable issue is that when the pack gets low enough, the car will take off in bursts on it's own. When I checked the pack with a checker, one cell was 2.8v, the other was 3.2v. My dynamite 2s/3s DYNC0505 charger doesn't seem to balance the packs very well as when I take them off the charger, one cell will be at 4.19 and the other at 4.14.

I ordered a couple new 300mah 2S packs for it.

Just glad it's working again.

 

[olds97_lss]

I'm 99% sure the traxxas servo died on me at some point, was just a cheap micro servo from one of my revo's that was for the reverse shifting. If I take it back apart, I'll look at it and see what's in there, but it has a servo saver on it now and I'm 99% sure it's a metal geared servo with more torque as well. The servo saver didn't fit the traxxas splined servo.

 

[lolazam]

Just wanna say I really appreciate this post. I was looking to repair a losi micro receiver and it was nice to see somebody trying to do the same thing and posting about it and its not from 10 years ago. its cool to see your progress and trial and errors in pictures. thanks and keep it up!

 

[Greywolf74]

Brings back good ole memories of my Losi DT