Go big or go broke, first super

[Jmsideshow]

So I have embarked on my first odyssey into the crawling community and I've decided that the best way for me to do that is to build my super entirely from scratch. Yeah, I'm probably a bit crazy but why buy it when you can build it and be unique.

This is gonna be the chassis plate. The prototype is going to be 1/8" aluminum and once the design is finalized, I'm gonna get them water jetted out of carbon fiber. It's 10.35" long and 3" tall.

This is one half of the split worm drive gearbox. It's about 3.25" tall, 2.5" deep, and 2 7/8" wide per pair .It's being machined from T6 aluminum by www.emachineshop.com and have a 20:1 reduction inside the box and a reduction from 1:1 to 4.05:1 using a spur pinion off the motor for a range of 20:1 to 87:1 gear reduction. All the shafts are full ceramic bearing supported for low drag and minimal power loss through the seriously heavy transmission parts. The worm gear system is sourced from mcmaster-carr and is seriously beefy, the aluminum shafts that they ride on will probably give long before I strip a gear no matter what power I apply to this thing.

Motors: NeuCastle 1515 725kva brushless
ESC: Dual Tekin RX8
Servos: Hitec 7990 front and rear steer
Radio: 4pks
BEC: CC bec pro
Links: 3/16" Titanium rod with traxxis rod ends
Wheels: Axial narrow rocksters
Tires: Mud slingers narrowed and sipped
Shocks: Aluminum HPI NItro MT4
Battery: dual 3s in series for 22.2v 2000mah "true 100c" from maxamps.com

The drive system from the diff outputs to the wheel hubs are gonna be sourced from the HPI baja, I figure a little larger will keep it stronger, damn the extra weight, it'll be less spares for me to carry to the rocks. :twisted: The hub carriers are gonna be the aluminum upgrades for the Savage XL with a little work to make the baja wheel drives to work with them. Unfortunately I've gotta settle for sealed needle bearings in the wheel hubs since I cant find ceramics that are only 2mm thick lol.

The chassis and links are yet to go into production so any suggestions are more than welcome. Let me know what you guys think and I hope to get it out to at least one comp in the North Jersey area sometime this year.

 

[im2tall]

I'm doing the same vv

except I'm not builing my axles I'm using super bullies!!Looking like you have alot of work ahead of you !!Good job !!Can't wait to see how those axles are gonna look!!Keep RCC posted!!:shock:

 

[Jmsideshow]

except I'm not builing my axles I'm using super bullies!!Looking like you have alot of work ahead of you !!Good job !!Can't wait to see how those axles are gonna look!!Keep RCC posted!!:shock:

NO doubt, I'll have regular updates for the entire build. It'll probably make it take twice as long.:roll:

 

[Aussie Nerd]

Only 2 things I can say, I'd go with tekin motors not castle, as the tekins are sensored for smooth startup. Edit I just noticed your KV, the lowest tekin go is 1350 so I assume that's why your going neu. And second get some real batteries, those maxamps are going to crap themselves the second the even see a 1515. But other than that I'm really looking forward to seeing the result of this"thumbsup"

Kieren

 

[Jmsideshow]

Only 2 things I can say, I'd go with tekin motors not castle, as the tekins are sensored for smooth startup. Edit I just noticed your KV, the lowest tekin go is 1350 so I assume that's why your going neu. And second get some real batteries, those maxamps are going to crap themselves the second the even see a 1515. But other than that I'm really looking forward to seeing the result of this"thumbsup"

Kieren

Yeah, the low kva rating and the +1000 watt power rating are the reasons I went with the Neu. As for the batteries, I'll definitely take it under advisement. If you've got any suggestions for an alternative I'm all ears. I'm looking for some smaller batteries that have really high C ratings (+100) so I can take full advantage of my forthcoming motors' high power potential.

 

[Aussie Nerd]

If you want high C rating look elsewhere. Maxamps has a very nice reputation for taking 15c-25c packs are rebadging them as 50 to 100c so the traxxas fan boys think they are getting something that's actually good quality:roll: Plus I had those exact packs back when they only had 50c stickers on them, and they couldn't even handle 40 amps without puffing let alone 200 amps! Try thunderpower, hyperion or turnigy nano techs. They all do TRUE 45-90c packs. It seems like you'll have a fairly hefty rig anyway, it might be better just to go with something around the atleast 3000 mark? Those smaller packs even with high C ratings probably aren't going to have to long a life if your drawing right on their rated amps.

Kieren

 

[Jmsideshow]

If you want high C rating look elsewhere. Maxamps has a very nice reputation for taking 15c-25c packs are rebadging them as 50 to 100c so the traxxas fan boys think they are getting something that's actually good quality:roll: Plus I had those exact packs back when they only had 50c stickers on them, and they couldn't even handle 40 amps without puffing let alone 200 amps! Try thunderpower, hyperion or turnigy nano techs. They all do TRUE 45-90c packs. It seems like you'll have a fairly hefty rig anyway, it might be better just to go with something around the atleast 3000 mark? Those smaller packs even with high C ratings probably aren't going to have to long a life if your drawing right on their rated amps.

Kieren

I had a look at the Turnegy packs, I'll check out the rest. I was thinking the same thing as far as capacity went but hadn't messed around with the lipo tech that much yet so I wasn't gonna invest much into the battery packs till I found something that worked out well.

 

[Aussie Nerd]

If you just want to try out your options definitely go with HK packs. I think turnigy, rhino and flightmax all seem to be alright. Just check the feedback. If there is few that got ones with dead cells or something just find another pack. There is usually about 3 of the same capacity and C rating!

Kieren

 

[Jmsideshow]

If you just want to try out your options definitely go with HK packs. I think turnigy, rhino and flightmax all seem to be alright. Just check the feedback. If there is few that got ones with dead cells or something just find another pack. There is usually about 3 of the same capacity and C rating!

Kieren

Spent some more time on the boards and I think I'm gonna go with a pack for cheapbatterypacks.com. The guy who runs it had a pretty good page on some testing he did and his stuff looks pretty solid.

http://www.cheapbatterypacks.com/?apage=prodpage.asp&invid=Elite3300-30C-6s&sid=766242&bc_menuid=

Also looks like I'm gonna be starting the chassis plates tomorrow. They're gonna be some aluminum prototypes lacking some of the adjustment options of the final versions but it'll be a start. Pictures to follow, hopefully lacking significant blood stains.

 

[Jmsideshow]

Prototype chassis plates from 1/8" aluminum sheet

Before

I chopped it into even pieces big enough for the plates

Then using some 3M spray adhesive I glued two plates together so I could make both at the same time.

Using more spray, I glued on the cad drawing of the chassis plate

and started cutting. An hour later this is the result:

I left extra metal around the shock mounting points so I could drill more holes to find the perfect shock setup before the final design.

Now we start drilling...and drilling...and drilling. 4 hours later THIS is the result

And once separated here are my completed chassis plates:

WOO HOO!!! Only took 6 hours to drill the bagillion holes. I'll probably use 5 total. The final design will incorporate generous lightening, and significantly less adjustment options and will probably be made of delrin of titanium. Haven't decided yet.

Thoughts so far?

 

[Jmsideshow]

Well, now that I'm waiting for my gear boxes to get here from the machine shop, I'm itching to do something with the project... Guess I'll narrow the wheels. I start tomorrow, but I need a good width to shoot for. I was thinking about 1 1/4", that sound pretty good with a set of cut and shut sedona's?

Maybe, if I have time I'll start mocking up some links and see how this thing articulates, pictures to follow.

Comments welcome."thumbsup"

Oh, the ceramic bearings are gonna have to wait till next season I think. I'm not about to drop $1k for a handful of bearings no matter how much they help.

 

[Jmsideshow]

This is gonna be a long one (that's what she said) but it's mostly just pictures so strap in and hang on.

Okay, well it's been a busy week and however long. I spectated at motorama and got a big box of parts. Now I'm super motivated again and actually got some work done and since I know people like pictures more than words here we go with a wheel narrowing:


Here's what I started with. Offset is a little excessive but I can work with it.

AS you can see they're pretty narrow already but I'd like a bit narrower

I figure I'll take out about \/this\/ much

Since I don't have no stinking lathe I gotta figure out how to do this with a bench top drill press or a bench vise and a hacksaw. How about I do this:

Then I do this:

Then I can use my hacksaw to make pretty much perfectly straight cuts around the wheel and I end up with four of these:

Now were about 1.5" wide and ready for cut and shut sedona/moabs whenever they finally get here. You can see the part I cut out in the top center of the picture there.

Next I need something to hold the wheels and let them turn. How about I use these Savage knuckles, the baja wheel shafts, and some bearings carefully chosen for minimal cutting.

Now the problem is the bearings don't quite fit into the knuckles, sounds like its time to grind. Once again, no lathe means we improvise again with the drill press.

The back side/ inner bearing is just a hair larger than the bore so it only takes a second with the grinder

we get this

Now I have to get the front bearing in which is gonna take some work since the smallest bearing I could find is 2mm larger than the knuckle bore. I traced around the bearing and scribed a line to cut to. At least the stupid purple anodizing is gonna be handy for something

After some judicious grinding with my make shift grinding rig, the bearing drops in almost like it was meant to go there.

these wheel adapters gotta go though. With these my track width is nearly 16" hex to hex. I've got a plan involving a threading die and some 17mm nuts that will get my track down to 13.5", that's a bit more realistic I think.


I've also changed the chassis plate design something a little smaller with a little better geometry.

I read so much about 1:1 4-link design my head nearly popped but I think the new design is a lot better. Now I just need to cut it out... again.

That's it for now. This weekend I gotta figure out how I'm gonna attach the knuckles to the gearboxes. Should be fun, I see lots of cut up cardboard and lots of bent steel for the prototype. I'll post more on this later.

 

[kk_kk]

fantastic machine job

 

[rik]

this is very cool. i like how you narrowed the rims with the drill press. very creative. i also think your new chassis design will function a lot better. great job. "thumbsup""thumbsup"

 

[dezrik]

what program are you using to design the chassis?

 

[Jmsideshow]

what program are you using to design the chassis?

emachineshop.com

can't beat it for simple designs. Free software and instant pricing for your designs. It's pretty easy to work with too.

On an unrelated note, costs for my "made from scratch" axles have officially spun out of control, and it looks like the only benefit I'm gonna get is a 1/2" of extra ground clearance and the satisfaction of going broke building something I could just buy. The steering angle is pathetic, the weight is ridiculous, and it's not exactly the most subtle answer for a problem that wasn't even a problem. Looks like a set of super bully 65:1's it is. I hope my motors still fit.

 

[Jmsideshow]

Okay, anyone know if ANYONE has some 65:1super bullies in stock? I can't find anyone that has a set and I'm not throwing any more money at my abortion of an axle.

 

[Psychomonkey RC]

I think that CKRC and JPCustoms has them in stock. "thumbsup"

 

[Jmsideshow]

I think that CKRC and JPCustoms has them in stock. "thumbsup"

CKRC it is. Super bully 65:1's on the way. "thumbsup"

 

[Jmsideshow]

CKRC it is. Super bully 65:1's on the way. "thumbsup"

Well there I go thinking again. Super bullies are on back order with no time frame for delivery. But while hanging a clock in my bathroom, i slipped, fell, and hit my head. When I came to I had an epiphany, a vision... A VISION OF... THE GAME CHANGER

Actually I just stole most of that from Back to the Future, but the game changer is real and it's gonna earn it's name. Details will follow. "thumbsup"