14s Brushless Savage
 

Hello fellow builders!


During the end of last summer I got the idea to build a "true" monster truck.

My main goal with the truck will be to do a huge & fast hill jump over the local kids ski hill in our neighborhood.

On the wishlist I had maximum voltage available and feasible in a truck. The first idea was to use a LS and put 14-15s Lipo & brushless in it.

I have years of experience in rebuilding my Savage X to hold up with previous set-up with 6s and Lehner 2230/9 motor and MGM esc. Hence I decided to continue on that track, but with heavily modified set-up.

Motor: Lehner 2280/8 (6kW)
Lipo: Hyperion G3 3300mAh 6+6+2s => 14s with short run time
ESC: Jeti Spin 200
FLM widening kit
Bullet proof diffs etc.
Center Differential.
Brake: No solution yet... Is it really needed to do a hill jump anyway?
Chassis: Mold my own stretched chassie in Kevlar and Carbon fiber.

Complete build and all details available on my Swedish building thread, but I will post images and answer questions here as well.

http://rsb.se/arena/showthread.php?t=48769

Kevlar and Carbon fiber on roll for making the plates for the chassis:

http://rsb.se/gallery/files/1/5/3/dsc_0184.jpg

4 layers of Kevlar as outer impact protection and then 10 layers of Carbon fiber - pre-cut is a must before starting the mold process..

http://rsb.se/gallery/files/1/5/3/dsc_0191.jpg

Epoxy during mixing and image half way through the lamination process

http://rsb.se/gallery/files/1/5/3/dsc_0192.jpg

http://rsb.se/gallery/files/1/5/3/dsc_0193.jpg

Image of the hardened plate. The blue coating is the release agent.

http://rsb.se/gallery/files/1/5/3/dsc_0196.jpg

After starting the cutting:

http://rsb.se/gallery/files/1/5/3/dsc_0206.jpg

Last image right now, comparison of the new plate and the original Alu-plate and my older Carbon fiber plate.

http://rsb.se/gallery/files/1/5/3/dsc_0212.jpg

Awesome project!

How much practice did it take to learn how to create your own CF and Kevlar laminates?

One Hellava Idea !

Liking the kevlar chassis, slick.

Will will need brakes, for in air adjustments for when making that thing fly ????

Yeah, I think I will need the brakes. At the moment I am thinking of just using the softbrake settings to get a basic brake system, but I also have two back up plans:
1. Disc brakes on the center diff, it is very tight, so I do not really believe in this solution.
2. Disc brakes at all for wheels. I have bought the axle extension system for the Savage XL and will machine new wheel hubs and mount some disc brake system from Large Scale models. a pity that the Integy kit for the Baja get so bad critic..

Anyhow, picture of the chassie, just roughly cut sofar.

http://rsb.se/gallery/files/1/5/3/dsc_0215.jpg

And here the FLM kit

http://rsb.se/gallery/files/1/5/3/dsc_0162.jpg

http://rsb.se/gallery/files/1/5/3/dsc_0219.jpg

Laminating in Carbon fiber or similar is really simple, just make sure to get all excess epoxy out of the sandwich, either by vacuum bagging or by mechanical force.

That's a serious Monster build!

That thing is bonkers- I love it! :lol:

I bet you could set a few speed records given enough room, should have the grunt required with that hoofing great lehner & 14s lipo...

I saw the lehner Monster compared to your RC18 !! :lol::lol:
Deutsche Qualität oder ? :yipi::yipi:
We are all impatient to see the beast finished :D

Where is this ?? Please direct or supply link.
Thank You.

http://rsb.se/gallery/files/1/5/3/dsc_0181.jpg

You can find it in the SWE forum link he has in the first post ;)

Thanks Bro, missed that somehow?

Impressive Mill !
Looks like a freakin' Soda can.

Wow... v nice. Will be watching. :)

Instant favorite! God, thank you for Brushless technology.

In the link he gave.

Thanks,

I will gradually transfer the images over here and write comments in English. I know my self how boring it might get when trying to understand the text in a foreign building thread if the language is completely non-understandable...

Here's a image showing the ESC and the motor, quite beefy to get into the chassis. I have added 1.5 inch to the wheel base.

http://rsb.se/gallery/files/1/5/3/dsc_0220.jpg

So, here's the most complicated and time consuming part of the project - making the lipo trays...

Parts for the molds coming up:

http://rsb.se/gallery/files/1/5/3/dsc_0231.jpg

http://rsb.se/gallery/files/1/5/3/dsc_0229.jpg

http://rsb.se/gallery/files/1/5/3/dsc_0239.jpg

I never tried the functionality of the release agent on the MDF material before starting the lamination - it turned out to be a very time consuming mistake.

I never had the time to take any photos during the lamination as it was very complex - sorry for that, but here's images of the result.

It looks a little wavy, but it is only the fiber direction on the two topmost layers of Kevlar, the surface is very flat and nice. These top layers were draped over the boxes after the trays were polished.

http://rsb.se/gallery/files/1/5/3/dsc03901.jpg

http://rsb.se/gallery/files/1/5/3/dsc03905.jpg

Cutting and grinding the final shape was done later in the project..

More images, now with lipos in it

http://rsb.se/gallery/files/1/5/3/dsc03910.jpg

http://rsb.se/gallery/files/1/5/3/dsc03908.jpg

Nice project
 

Nice project. This is the first time I have seen anyone doing so much of their own fabricating for an R/C build. That is cool that you have so much experience with the laminating process to come up with such a unique project. Keep up the good work. I can only imagine what 14S is going to do with that motor setup.

Next part was a top chassis plate to bind the servosaver with the center diff assembly and the side plates. As it also should act as a stop and protection of the Lipo from the main gear it needed a 90deg angle.

8 bidirectional layers of carbon fiber = 2mm

By the way - the layers of fabric in the lipo trays was bidirectional.

http://rsb.se/gallery/files/1/5/3/dsc_0221.jpg

What are the kV and weight of your 4,4kW motor ^^
If we do the comparison, 1520/1Y NEU-CC is rated average 2kW :D :D
This savage will be a monster

kV is 925, weight apx 800 grams - Lehners, Neu or other HQ motors have approximately the same power/weight ratio. Availability and my experience of Lehner motors was the base for my choice. I know there are tons of opinions in this area...

It will be interesting to analyze the logging data someday

Here is the lehner motor data on 14s = 50V from their webpage http://www.lehner-motoren.com
The data @ 186A is the peak efficiency data

Motor type*2280/8, Windungen Windings*8, Spannung Voltage*50 V, Ri*8 mΩ
Current Input power rpm Momentum Output power Efficiency
/ A / W / min / Ncm / W / %
50.00 2,480.00 45,868 49.00 2,187.33 88.20
100.00 4,920.00 45,498 104.12 4,572.84 92.94
150.00 7,320.00 45,129 159.23 6,880.22 93.99
186.00 9,023.23 44,862 198.92 8,493.71 94.13
200.00 9,680.00 44,759 214.35 9,110.46 94.12

50k RPM at fully charged Lipo :yipi::yipi:
With 200A continuous current :yipi::yipi: ===> TORQUE :yipi:
94% efficiency :D :D :D
What will be your gearing ? Trying to get the 80 mph ?
The price of this german motor ? ;)

2280, hmm I think you should throw it out and opt for the Lehner 3080! :lol:

Awesome build!

About $500-800 USD...



Cheaper to buy a Neu equivalent over here!

Awesome project man. It will be interesting to see how everything holds up if you do the jump. Good luck.

A lot of parts will break - but I am willing to take that:party:

The 30 series of motor have larger diameter, so I would have to use other setup on the spur and pinion. Apart from that, there is space enough in the "motor compartment"..

Gearing, 48t spur and 12 - 18 on the pinion available => pretty darn fast anyhow..

The price will be equal for Neu vs Lehner for me as I would have to pay +25% tax on the Neu motor + the swedish postal service fee for being so kind and adding the tax...

Center diff setup i presume ?
And the diffs ? 10/43 ;)
Can you show us a picture off the hill you wanna jump ? :lol:

Pretty sure he is going with the "bulletproof" HPI diffs in the Savage X. 29/9 or 3.22 ratio.

I'll be watching. This should be one awesome vehicle.

Bonus: Added the picture of a brushless Serpent 960 were I had to make a quite advanced carbon fiber chassie in order to fit the Lehner 2230/9 and 6s Lipo in the center of the car.

http://rsb.se/gallery/files/1/5/3/dsc_0107.jpg

Finally the Lipos blew up and all other seem to be a few notches to large - so now it is just resting on the shelf :cry:

It was doing >100Mph and was built in the beginning of 2008 as a commercial for another project..

[YOUTUBE]http://www.youtube.com/watch?v=bYukCewlAx0[/YOUTUBE]