Typhon The mega upgrade **Now with oversized Brushless POWA!**

[kenm04]

I suck at naming.

Anyways this is the journey of taking my Typhon mega 4x4 from mega to what ever it ends up as in the end.

The planned wish list is the same as any other but there are a few extras that I plan on playing around with such as a Custom transmitter and receiver with telemetry.

I've been holding off on making this thread until I actually had to replace parts. And the spur gear was the 1st to fail and get an upgrade.

I went with the Arrma 57t CNC steel spur gear and an RRP 11t pinion gear to keep the gear ratio as close as possible. (stock = 5.353:1, new 5.182:1)
I had previously been debating between the HD spur gear and the steel one because of a comment about preferring the spur gear to get chewed up vs a pinion gear. After getting the new gears I realized that chewing up the pinion might actually be the better way to go because:
Pinion costs as much as a new spur
Pinion gears aren't limited to a specific brand, and since arrma has parts issues, I'd rather have to swap a pinion that I can get from anywhere rather than wait for an arrma spur gear.
I'll be swapping out the pinion gears anyway for different battery and speed conditions.

Before changing out the gears I had failed to check and see that the shaft adapter would need to be changed out when going from the mega spur and slipper to the blx spur and slipper. Thankfully the shaft adapter is aluminum and I just ground and cut off the extra length shown sitting where the battery normally would in the image above.

The next upgrade will most likely need to be the motor and ESC as now when I run the Typhon, the motor smells like burnt enamel motor wire but I don't see any over-heated windings yet. The plan for the motor ESC upgrade will be a hobbywing Max 10 SCT with a Hobbywing 4267 2600KV then play with pinion gear size.

 

[SrC]

DId you clean out that Brushed motor yet?
It needs servicing regularly. It has no Ball Bearings and gets a drop of oil at both brass Oilite bushings.
Use a motor spray / Electrical contact spray solvent, to flush out normally wearing Brushes. (dust)This collects inside the motor as does dirt ingress and fouls out everything including the brass bushings. If staying with brushed, I would invest in a rebuildable type brushed motor. I do this in my Crawler brushed motors. The rebuildable motors have Ball bearings like Brushless do. They also run way cooler. Are rebuildable and can be opened up for better cleaning, lubing the BB's and Motor Brushes can be easily be replaced unike sealed can motors like the stocker you have. Consider a 1/10 Fan and HS set. Hot running brushed motors reduce run time drastically.
Rebuildable non-fixed endbell upgrade motors can be had cheaply. In some cases cheaper than the stockers (Fixed endbell type motors)
Apex and Hackmoto brand brushed motors come to mind, what I also use. I also run a Holmes Hobbies brushed rebuildable motor. Considered the best.
My Crawlers for me run best with Brushed motors. Harcore bashers these days run BLX.
Upgrading to BLX will require a bit more upgrades to the drivetrain besides just the steel spur. BLX has way too much more torque/power for a basic Mega drivetrain.
To your comment, yes, I would rather destroy a pinion than a spur gear any day. Pinions are always the cheaper part. And easier to replace.

 

[Edough13]

Going good so far it looks like. Ya I highly suggest the steel spur over the plastic and even if you cut the slot in the chassis or try to seal the PM it will still fail and get chewed up eventually. Also as you said you can find a new pinion about anywhere if it does get damaged from a bad gear mesh and a lot cheaper to replace. I'd suggest when you go brushless to at least run a 13t pinion or 15t so motor rpms aren't through the roof running the smaller gearing. I've ran same pinion and steel spur in my Granite for about a year now without a single issue. Even running it on 4s and sending it as hard as I can both spur and pinion look the same as the day I installed them. I also cut the slot under the spur in the chassis as IMO and experience that is the best option to save your motor bearings and spur/pinion. Just an example when I got the vorteks I purposely left the PM alone to see how long the plastic spur would last and on the 3rd pack motor bearing blew and spur was eaten up also. So since put slot in chassis and went to steel spur and after 10+ packs with my son driving it as fast as he can on our soft sandy dirt not a single issue yet.

 

[kenm04]

@SrC No, I'ven't cleaned or rebuilt the motor yet. The thought did cross my mind though while looking for a thread locker. Even using contact cleaner crossed my mind but I was still concerned with spraying something into the motor and possibly getting more packed crud to build around the brushes and in the bearings.

The fan and heatsink idea isn't bad a bad one and I didn't even think of doing it. Granted I was more concerned about getting the Typhon up and running again, it had sat ideal for a month due to the spur gear and me experimenting with the stock radio gear and a Dumbo RC set. All of which had the soldering iron was taken to them and none of them technically functioned...I stole the RF modules from the dumboRC stuff and thought I could use the IPX connecter and antenna from the stock receiver and re-use it on the dumboRC stuff before I removed the RF modules. Needless to say, I lost the IPX connector and with no RF modules, I had no working radio systems. Luckily the stock receiver has a PCB antenna, so I just had to make a solder bridge and the stock system worked again, albeit with a shorter range but good enough for tracks and bashing around the yard.

I'm also still curious as to where all the metal powder came from inside the gear housing. Before switching gears I had, still have a bunch of metal powder that is magnetic clinging to the motor screws inside the gear housing

@Edough13 I had seen where people had cut slots for the gears, although It seemed like there was enough clearance with the stock gear housing and the new spur gear to the chassis so I didn't modify the chassis.

I double-checked the motor calculations, if I get a hobbywing 4268 2600KV motor. I should be able to at least 17MPH on with my current 2s packs provided the 4268 will run on 2s.

And up to 30+MPH with 2s if I go up to the RR 23t pinion.

And potentially up to 70+MPH on 4s with 23t pinion.

 

[kenm04]

Looks like I'll be upgrading the motor and esc. I think the stock motor dissolved the positive brush armature, brush and part of the arm itself.

 

[Edough13]

Yes the point of the slot in the chassis is not to help it clear the chassis but rather to let dust or debris fall out and not damage the gears getting stuck inside the PM.

 

[kenm04]

As mentioned in post #5, the positive brush in the stock motor disintegrated. And I needed a new motor.

Previously I was tossing around the idea of a max10 sct and a 2600kv motor. After overthinking which motor and ESC, I felt that oversizing a little would be a good thing so I went with a Max 8 and a 2200KV motor.

Figured this would allow for some decent gearing while keeping temps low at anything from 3s to 6s, and see if the Typhon self-destructs at 6s or not.

The first order of business, figuring out where I was going to mount the ESC. The stock location doesn't work with Max 8 since it's bigger, at least it doesn't sit on the receiver box nicely. The left side of the chassis is a no-go so that just leaves between the receiver box and the motor. However to even see if the ESC fit in that location I had to be able to mount the motor. I didn't have a 3s motor plate, but I was curious if the stock mega motor mount would work, and it does nicely. With the motor mounted to the power module, I just had to clip it in and then which orientation would work. Turns out only one, and with little room to spare.

The only problem with this spot is that there is a post, two ribs, and two screw mounts. The ribs and screw mounts weren't that big of a deal, but the post had to go. After cutting the post out I realized the two screw mounts stood just a little higher than the ribs so they got trimmed.

Next was figuring out how I was going to mount the ESC and get it out if and when I need to remove the power module. At first, I thought about screwing the bracket that came with the ESC to the chassis and then using the adhesive strip to hold the motor down, as this would also allow space for the servo cable to get back to the receiver, but then I wouldn't get access to the screws to remove the bracket which would also be in the way of removing the motor. Velcro was the next and simplest idea, however, I didn't feel that it would hold the ESC down when I started really bashing and I couldn't find any in the house and nor did I want to buy any. Which lead to the only option I could think of, drilling holes in the chassis and then mounting the ESC to the chassis via screws.

I started out using the bracket the came with the ESC as a template since the holes of the bracket matched the holes on the bottom of the ESC. However, I forgot that the ESC overhangs the bracket so I had to re-drill the holes after I had drilled all 4. Worse still, was that after I tried to reposition the bracket and drilled the 1st hole to try and align it to the ESC, I noticed that the hole needed to be elongated. Now I'm left with L-shaped slots basically to mount the ESC.

Luckily though the heads of the screws for the ESC are big enough to cover the funky holes. The only issue was the screws heads were sticking up and could catch anything if the chassis got too low to the ground or if something stuck up high enough. I didn't have any counter boreholes for the heads so I used a slightly oversized drill bit to make the indentation, although one of them, the drill bit into too much and started going all the way through.

Just need to tuck the servo cable under the sides of the ESC and run it to the receiver box after installing the power module.

Now that just leaves the question, what gearing? Did a little digging and seems like a lot of folks are running between 17 and 21t with the majority around 17t or 18t, excluding crazy speedrunners who are doing 26t+ pinion and 35 - 48 spurs. I wanted a good range of choices including low gearing in case I wanted a calmer drive or higher gearing to see how fast I can go without getting duplicate gear sizes or too few gears. Found these on amazon.

I neglected to read that these are for a 1/8in shaft and not the 5mm shaft of the hobbywing. After realizing that I bought gears with the incorrect shaft size I decided to see how hardened they were. I'm no metallurgist or mechanist, but if I can take a standard carbide drill and a jewelers file to enlarge the hole to 5mm, then I don't think they are hardened enough or at all. Took me about an hour first-hand drilling out the bore to 3/16 in (4.75mm) and a set of jewelers files, I was able to enlarge the bore so that the gear fit the shaft perfectly without any wobble. Installed it and set gear mesh.

 

[kenm04]

All that's left is to tidy up the motor leads so they don't bounce around or get in the way of the body. And since I don't have any lipo's other than the 2s's I bought to run while this was still brushed, I'll just have to run it as dual 2s packs.

Next up is deciding if I'm going to convert my 2s packs to xt90 or convert the ESC to EC5, find a nice easy access home for the power button, install the center shaft support bearing when it gets here at the end of the month, get a 3s motor mount, and design up a 3d printed motor support/fan mount.

Oh and get a video of how squirrelly this is with stock settings and the controller set to 100% and the battery at storage charge since I haven't charged them to full since buying the new house.

 

[arrma only fans]

put Velcro between the batteries so they don't fall out, I had that problem

 

[kenm04]

put Velcro between the batteries so they don't fall out, I had that problem

You called it! Except....the one pack didn't fall out, it shot out the front. I'm starting to wonder if the battery dislodging and ejecting out the front caused all the carnage and not the 3in piece of my drive way.

On that note, I priced out all the parts fix everything that's broken and get some parts to replace parts that I think were stressed or fatigued. And the total came to around $300 which begs the question:

Do I buy all the parts and fix it?
Do I buy a brand new typhon mega and use the old good parts as spares?
Or do i try and get a used 6s typhon or 6s typhon roller?

 

[arrma only fans]

You called it! Except....the one pack didn't fall out, it shot out the front. I'm starting to wonder if the battery dislodging and ejecting out the front caused all the carnage and not the 3in piece of my drive way.

On that note, I priced out all the parts fix everything that's broken and get some parts to replace parts that I think were stressed or fatigued. And the total came to around $300 which begs the question:

Do I buy all the parts and fix it?
Do I buy a brand new typhon mega and use the old good parts as spares?
Or do i try and get a used 6s typhon or 6s typhon roller?

Pics? Also check out Jenny’s…

 

[kenm04]

Pics? Also check out Jenny’s…

Post in thread 'What did you break today?' https://www.arrmaforum.com/threads/what-did-you-break-today.8928/post-646153

 

[arrma only fans]

Post in thread 'What did you break today?' https://www.arrmaforum.com/threads/what-did-you-break-today.8928/post-646153

Get this, move all the electronics wheels and body over to this chassis, it will run smoother because it is new.

https://www.ebay.com/itm/NEW-Arrma-...2349624.m46890.l49286&mkrid=711-127632-2357-0

 

[kenm04]

I had seen that and thought about it, but when I brought it up to the wife of buying rollers or just flat out buying a new mega 550 and then selling off what I didn't need/want she said no. But, I did take your advice and checked out Jennys, ended up buying almost everything from there for $70. The only things I didn't buy from jennysrc, because I couldn't, was a new power module, fast eddy bearing kit, and RPM front a-arms for around $66.

The only thing I'm missing out on is getting a CNC front diff, maybe next year I'll buy those finally.

 

[kenm04]

Got all put back together and did a speed run.

approx 500ft in 11sec, 45 Ft/s, or around 30 MPH.... Then yesterday when I took it, I realized I had the controller set to 50% throttle limit. Repeated the test and did the 500ft or so in 7-8 sec, right around 48MPH.

Compare that to the calculations, and it's pretty close!

 

[kenm04]

Got the steel rod, badlands, and LED headlights in. The rod was cut to hub pin length, installed, and badland mounted! Then took it for a spin to what difference the badlands make.

Now to design up a headlight mount and design a two-stage light controller to control the headlights with the transmitter.

Running 4s and punch 2 on the ESC.

 

[kenm04]

Made a test piece to clamp the headlights since I didn't have the front shock tower to take measurements and design a headlight holder to fit. Anyways just temporarily placed the clamping piece on to an old front shock tower to get an idea of how it would look.

Also took the Typhon to the in-laws yesterday to drive around, they have a large front yard to drive around in the grass with, and ended up unglueing both rear tires off the rims with the controller set to 75% or 100% throttle control. Managed to tuck the foam back in and reseat the tires but could only zip around at 50% throttle.