e's ExMT

[ekd]

It's here! After much thought, and a bunch of lurking here... I decided to get a crawler, and chose the Mad Torque to cut my teeth on. I've just run it a bit, but I'm hooked.

Modding stuff is a lifelong passion, but I have never cut a gear, so after looking over all the choices of RTRs (so I can learn as I break stuff) it became clear that this rig's steel innards made it an obvious choice. The fact that some skilled guys here have already laid a good trail (but not yet a highway) makes this attractive as well.

It can't be discounted that a complete set of gears (both options) cost me $10... from hobbypartz, a few hours south of me. Or, that the axle housings cost $3.50 a pair... it's more fun to mod, sometimes, when you can afford to screw up royally.

The rear steer parts are ordered, and I am going to try to learn to drive with a stick asap.

I'm watching with interest as the hunt begins for CVDs... but there is plenty to do here in the meantime. I would very much appreciate any comments or ideas from you guys, and promise to share mine... no matter how dumb. I'm in this for fun.

8)

 

[ekd]

I have the electronics figured out. A while back, I got a hell of a deal on 7 Losi Strikes for a family fleet. They were the defective ones (I was aware when I bought them), and Losi's CS made me as close to a fanboy as any company ever has. They replaced the ESCs without question, and allowed me to keep the bad ones. Here's the deal: The reverse is super weak in the regular mode... but in crawler and race mode, they work fine.

They are only good for 2s (12T), but that fact makes other design considerations moot. I will be running mounted A123 cells, so I will be working with 6.6V... which makes it unnecessary to buy a CC pro BEC. Cheap servos will either have to dance to that music, or burn... "thumbsup" First up will be 3 $12 Tpro MG946Rs... :twisted:

This system will only cost me the price of a couple good motors... not bad idea anyway. I just need to get some advice on what to buy. I'd like to get more speed, but not at the cost of (2) 3s ESCs and a good BEC.

Any thoughts? Anyone?


Edit: I just ordered a Punk computer. As if I don't have a lot to learn already... :roll:

 

[ekd]

I like the Max Stone axle housings a lot better.

http://www.nitrorcx.com/18maxstrocr.html

They look like they could be modded by shaping the inboard flange to match. If anyone has a 'stone, I'd appreciate knowing the flange diameter, and the length of the housings from the base to the pivot hole.

I really want to clock these axles before making brace/servo mounts, and those housings have stout, low mounting points.

Also, does anyone have the Punk programmable computer, and do you like it?

 

[ekd]

I had to see what a difference getting rid of clod stall would make, so I threw it together and ran it. I'm glad I went this route.

It's a rat's nest, but when the Punk shows, I'll wire it right.

 

[demonoid369]

It looks good, don't get discourage if no one replies, I like how you have read up on your stuff which I must applaud because not much people do that

 

[ekd]

It looks good, don't get discourage if no one replies, I like how you have read up on your stuff which I must applaud because not much people do that

You know, I was just beginning to wonder if I was talking to myself... :mrgreen:

ExMT owners are a small group in a small (super) world... I don't expect much response, but do hope we can help each other find what we need. I like modding stuff that isn't covered (better than I ever could) by tons of companies. I had a custom MC shop back in the day before you could put a Harley together without buying a single part from WI. Then, things went nuts... and we began to tell customers "It takes more than a credit card and a Crescent wrench to build a true custom." I'm here, and starred up, to enjoy the "one off" stuff.

I went ahead and ordered the 'stone parts. A $10 experiment. Those parts are the only thing I like better about the 'stones. I'm pretty sure I can make them work... if the length is close.

I was looking at the hexes monkeyracer found, and started to poke around the other Exceed parts lists, and found these:

http://www.nitrorcx.com/mad-bd2003.html

I wonder what the difference might be? I wish we had a place to collect info on parts compatibility and dimensions... (hint, hint).

 

[ekd]

This is as far as I'm going with this until I finish the custom axle/trans housings. Those parts will be here tomorrow. It'll end up with axle mounted shocks and batteries, so DIY custom shocks and TVPs are coming soon. It's obvious there is a lot to lose in plate weight, and gain in CG.

It will already climb a wall to the degree shown, and cross RR tracks without hesitation... so it's already becoming a fun urban rover. The A123s actually didn't reduce wheel speed as much as I feared, and I have enough torque (but maybe not a Mad dosage) for now.

Also coming tomorrow are the other 2 cheap servos, and a cheap FPV wireless rig. The servos will be wired directly to the batts, and the cam setup will be detachable. I'm kind of excited about trying crawling from my wheelchair. "thumbsup"

I set a personal record yesterday...

I've been building grossly overpowered bashers for a while now, and I have never made it through more than 2 outings without ripping gory chunks off of a rig. So far, I have tripled that without breaking a thing. Is this what it feels like to be all grown up?

Tool induced carnage tomorrow, I promise. :mrgreen:

 

[monkeyracer]

Just saw this thread. Good start so far and good luck with the build going forward.

Comments:

The madbeast hexes look to be exactly the same as the madfire hexes, except the madfire hexes are half the price.

The Maxstone tubes look interesting, and I would love to see what you do with them.
I was thinking of making an axle brace, similar to what abavuso did, but not in the same way. for clocking the axles, I was looking at the MT flanges and think they can be clocked, but I haven't had much time to work on the MT.

I bought a punk dig, but haven't installed it yet, and actually I am looking at doing the FS-GT3B hack for 6 channels, dual ESC with rear steer mixing.

The MG946R's will be fine on 6.6V, and can handle 7.2V just fine. I am looking at getting a 1/4 scale servo for each axle for my build, since I don't like the idea of the servos fighting each other if they are not perfectly synced.

For motors, the stock are around 70t, so pick up some inexpensive 55t or 45t motors. These often pop-up in the classifieds or ebay for decent prices. I got a set of 55t's that I cleaned up, cut the comms, replaced the brushes and springs, and removed the stickers, and they look and work great. Much better drag brake, torque and wheelspeed.

I moved my shocks to the axles since I hate link mounted shocks (too sloppy, no matter how you do it) and the chassis is my own creation to allow them to mount up.


What part of Central Coast? I am from Lompoc, and miss Cali a lot. Will probably plan to head back when I am done with Engineering school.

Keep up the great work, I'll be watching this thread now.

 

[BentMetaL]

EKD, might want to load up the front with some lead. I wrapped the front rims with 6 ozs and got some 1/4" led fishing wire from Wally World. mad almost 6 wraps on the front axles. This is still not enough to make the tires grab on slick rocks. Tires will be my next purchase. I think I'm going to try the proline 2.8 badlands. But I'm not sure they will work on beadlocks. I'm also going to narrow the chassis and split the upper links.

 

[ekd]

Just saw this thread. Good start so far and good luck with the build going forward.

Thanks!

Comments:

The madbeast hexes look to be exactly the same as the madfire hexes, except the madfire hexes are half the price.

When enough guys are playing with these, I hope we can get a stickie with all the conversions/equivalents going. I don't care if it's only a few bucks, half price is... half price!

The Maxstone tubes look interesting, and I would love to see what you do with them.
I was thinking of making an axle brace, similar to what abavuso did, but not in the same way. for clocking the axles, I was looking at the MT flanges and think they can be clocked, but I haven't had much time to work on the MT.

I think they can too. We'll see what works... :mrgreen:

I bought a punk dig, but haven't installed it yet, and actually I am looking at doing the FS-GT3B hack for 6 channels, dual ESC with rear steer mixing.

Oh boy! More homework... more fun.

The MG946R's will be fine on 6.6V, and can handle 7.2V just fine. I am looking at getting a 1/4 scale servo for each axle for my build, since I don't like the idea of the servos fighting each other if they are not perfectly synced.

I think your way will be much cleaner, and cost effective. I'm going to end up with a rig bristling with servos, so I want a standard size for all. I intend to link the 2 with a bar, slotted for the aux servo so it has a bit of travel before it joins the main on the load. We'll see if that helps.

For motors, the stock are around 70t, so pick up some inexpensive 55t or 45t motors. These often pop-up in the classifieds or ebay for decent prices. I got a set of 55t's that I cleaned up, cut the comms, replaced the brushes and springs, and removed the stickers, and they look and work great. Much better drag brake, torque and wheelspeed.

I'm on it.

What part of Central Coast? I am from Lompoc, and miss Cali a lot. Will probably plan to head back when I am done with Engineering school.

Monterey county. I hope there is good work waiting for you here... Lompoc is as nice as it gets on this planet. I'd be a bit homesick, too.

Keep up the great work, I'll be watching this thread now.

Thanks. Again. Glad for the supervision... "thumbsup"

***

 

[ekd]

EKD, might want to load up the front with some lead. I wrapped the front rims with 6 ozs and got some 1/4" led fishing wire from Wally World. mad almost 6 wraps on the front axles. This is still not enough to make the tires grab on slick rocks. Tires will be my next purchase. I think I'm going to try the proline 2.8 badlands. But I'm not sure they will work on beadlocks. I'm also going to narrow the chassis and split the upper links.

Yeah, the tires suck for crawling anything slick or wet. I want to try cut and shut someday, but I plan to destroy some basher tires before I start cutting new tires up. Some guys make it look easy... I can do the exact opposite with very little provocation. :mrgreen:

I'm debating going 4 link, I have to study up on the pros and cons. Why do you plan to?

 

[monkeyracer]

Lompoc is nice, but I'll likely end up more south, closer to LA area, but hopefully not too close to LA. Depends on where the job offers are. Colorado is nice, but it just doesn't compare to the Central Coast for sure.

As for the build; I am looking into an easy way to do 4 link for these, but that will depend on how I clock the gearboxes.

The slot idea for the "slave" servo is interesting, but I'm leary of how it would work in action.

If we can organize the mods a little better, I think one of the moderators would be willing to sticky the post. I'm looking into CVDs/universals to get more steering and beefen up the axles. Still need more research on it though.

 

[ekd]

The slot idea for the "slave" servo is interesting, but I'm leary of how it would work in action.

If we can organize the mods a little better, I think one of the moderators would be willing to sticky the post. I'm looking into CVDs/universals to get more steering and beefen up the axles. Still need more research on it though.

I don't know enough about servos to comfortably bet more than a beverage that this will work... but, it's worth $24 to me to find out. We'll know pretty soon.

If the build threads on these continues to be of the quality seen so far... it shouldn't be long before we can put together something very helpful to the folks who wander in later.

I just read up a bit on the FS hack. I have so much to learn here. I'm hoping to get full function from the right stick of my 6, and leave the left for controlling the cam.

Why do you plan to go 4 link? Are there any advantages to a 3 link?

 

[monkeyracer]

Why do you plan to go 4 link? Are there any advantages to a 3 link?

The 4-link gives a little bit of rotational stability. That and there is a lot of slop in the 3-link connector that comes with the EXMT.

Also, I want my links to have the same axis of travel as the axis of rotation in the rod end to provide unhindered movement and better stability. (The lower links already do this.)


I'm looking into the GT3 hack to get easy proportional dig and 4ws functionality. I have a 6 channel radio modded into a pistol case, and it can work for that function, but it is much harder to accomplish. Also switching between the Super, my 2.2 TTC 4WS/Dig/winch Trail Rig, my drifter, rally truck, monster truck basher, and two other scalers, it is a lot easier to do with the FS-GT3 than with the FS-T6A that I have now.

 

[ekd]

The 4-link gives a little bit of rotational stability. That and there is a lot of slop in the 3-link connector that comes with the EXMT.

Also, I want my links to have the same axis of travel as the axis of rotation in the rod end to provide unhindered movement and better stability. (The lower links already do this.)


I'm looking into the GT3 hack to get easy proportional dig and 4ws functionality. I have a 6 channel radio modded into a pistol case, and it can work for that function, but it is much harder to accomplish. Also switching between the Super, my 2.2 TTC 4WS/Dig/winch Trail Rig, my drifter, rally truck, monster truck basher, and two other scalers, it is a lot easier to do with the FS-GT3 than with the FS-T6A that I have now.

Thanks. Please document the work on your radio? Your threads are among the very best.

I saw the price for another stock ESC is $15. I won't need one, but it sure seems like an easy way around clod stall (and going with lower T motors). For an econo rig, it could be the one of the most cost effective mods going. If anyone tries it, I'd like to know how it goes.

 

[John-e Bravada]

I guess it's time for me to chime in on one of these MT threads. I'm also building one. I went the $15 stock dual ESC route. I'm mixing ESCs with a 6ch hacked GT3B and running rear steer with it as well. I ran dual stock servos in the front till I burnt up one of them now I'm running dual Atlas servos on a bracket similar to BIG E's. I made an OTA setup with the knuckles flipped to the back of the axle to help the ackerman angle. I’m running AX10 Hysteer Al outer knuckles. I have Venom knuckles to clock the inner knuckles to try and get my caster back in shape but I haven't started that yet. I had problems with the 3-link bracket coming loose so I made my own brackets and converted both ends to 4-links. I stretched the wheelbase with S-bend Delrin rear lower links to 17.75". I'm running 55t motors and CC BECs front and rear on 2S lipos. The stock ESCs don't have a cut-off so I made a Micro Scream for it. For wheels I cut a set of 40 series Axis bead locks to 1.5" and cut and shut a set of Moabs like Abavuso. Traxxas Revo hubs brought the track width back in check.... I think that's the list so far. I have a set of HPI 4.5" rims and 6 Sedonas on order. I also have a set of AX10 CVDs on order to se if I can cut and shut them to work in the MT axles.<?xml:namespace prefix = v ns = "urn:schemas-microsoft-com:vml" /><v:shapetype id=_x0000_t75 stroked="f" filled="f" path="m@4@5l@4@11@9@11@9@5xe" oreferrelative="t" o:spt="75" coordsize="21600,21600"> :mrgreen: <v:stroke joinstyle="miter"></v:stroke><v:formulas><v:f eqn="if lineDrawn pixelLineWidth 0"></v:f><v:f eqn="sum @0 1 0"></v:f><v:f eqn="sum 0 0 @1"></v:f><v:f eqn="prod @2 1 2"></v:f><v:f eqn="prod @3 21600 pixelWidth"></v:f><v:f eqn="prod @3 21600 pixelHeight"></v:f><v:f eqn="sum @0 0 1"></v:f><v:f eqn="prod @6 1 2"></v:f><v:f eqn="prod @7 21600 pixelWidth"></v:f><v:f eqn="sum @8 21600 0"></v:f><v:f eqn="prod @7 21600 pixelHeight"></v:f><v:f eqn="sum @10 21600 0"></v:f></v:formulas><vath o:connecttype="rect" gradientshapeok="t" o:extrusionok="f"></vath><?xml:namespace prefix = o ns = "urn:schemas-microsoft-comfficeffice" /><o:lock aspectratio="t" v:ext="edit"></o:lock></v:shapetype>Time will tell. If I wasn't working on a bodyless chassis for an AX10 I'd be building one for my MT.
<o></o>
<o></o>
I think that's it for my Hy-jack Sorry, keep up the experimentation!<o></o>

 

[ekd]

Side by side. The stone's take 8 x 16 x 5mm bearings, the MT takes 6 x 10 x 3mm.

The mounting flanges are completely different... enough so that it seems to make the most sense to graft the MT flange to the Stone tubes. If the MT flanges were cut with some tube left on them, it could be turned to fit into the bigger ones... giving tubes with nearly double the thickness at the base, heavier Cs (replaceable), and at any length desired.

If CV axles can be found close to the stock lengths, these parts can easily be combined to fit them.

 

[ekd]

I guess it's time for me to chime in on one of these MT threads...
<o></o>
...I think that's it for my Hy-jack Sorry, keep up the experimentation!<o></o>

Nothing to be sorry for! If you don't want to start a thread, go ahead and put the juicy stuff in this one. I'd like to see it all, either way.

And welcome, noob! Finally, I have someone to pick on! :mrgreen:

 

[monkeyracer]

Good find on the Madstone tubes. They look much beefier than the Torque tubes.

I've still got some other ideas I want to try, but need to order some parts first.

 

[ekd]

Can't wait to see what you're thinking.

The Stone tubes are 20mm OD, and 14mm ID (nearly out to the hex C mounts). The MT's are 7.5mm ID, and >14mm all the way to the base of the Cs.

As soon as I have definite lengths... I want to use common CVDs, without mods... I'll turn the MTs down to a nearly interference fit, and have an infinitely and repeatedly clockable (set and pin) setup with nearly 7mm thick walls (full length, if desired). That ought to hold a screw or 2. The Al Cs and knuckles would finish this nicely (but not cheaply).

Can't wait to see what Abavuso comes up with on the trans bracing.

Can someone please tell me how to hook my vid receiver to my laptop (2 RCAs)? For the electronics end of this, if you assume profound ignorance on my part... you'd be doing us both a favor.

Edit: found this... love newegg anyway... bought it. http://www.newegg.com/Product/Product.aspx?Item=N82E16812270387