Homemade brushless baja
 

After converted a from nitro to brushless real Baja and sold it cause need of money, I decided enjoy making an homemade baja starting from my Savage and inspiring myself with two baja project founded in this forum.

I started the project from savage, making an homemade chassis as in photo:

http://lh6.ggpht.com/_GS-R7ugwb24/Sn...6072009156.jpg

I used my Neumotor 1521/1Y (1577 rpm/v) and a mamba monster max with
6s zippy lipo.

http://lh5.ggpht.com/_GS-R7ugwb24/Sn...9072009168.jpg

I bought the real baja wheels, but the seller sent me wrongly 4 rear tires, so I'm waiting for 2 front tires yet.

http://lh3.ggpht.com/_GS-R7ugwb24/Sn...5082009175.jpg

http://lh5.ggpht.com/_GS-R7ugwb24/Sn...5082009179.jpg

http://lh3.ggpht.com/_GS-R7ugwb24/Sn...5082009181.jpg

So in my summer holiday I completed my homemade baja with bowtie MTS savage wheels for the firsts running tests.
I decided to make it 4wd also.

http://lh3.ggpht.com/_GS-R7ugwb24/Sp...0/DSC01305.JPG

http://lh4.ggpht.com/_GS-R7ugwb24/Sp...0/DSC01402.JPG

http://lh6.ggpht.com/_GS-R7ugwb24/Sp...0/DSC01404.JPG

http://lh6.ggpht.com/_GS-R7ugwb24/Sp...0/DSC01405.JPG

http://lh4.ggpht.com/_GS-R7ugwb24/Sp...0/DSC01412.JPG


This is a small video:

[YOUTUBE]http://www.youtube.com/watch?v=7WrFDgbHJ5k[/YOUTUBE]


I'm really satisfied from it, it runs very fast and motor temperature was 67 C° at max on grass/dirt/stones terrain, battery autonomy was great similar with savage (about 20-25 minutes with zippy 5000 mah 20c).
In the future I will test it with eagle tree system for better relevations data.

thats........Awsome mate ,what motor you got in it?

It is a Neumotor 1521/1Y (1577 rpm/v)

what esc, batteries, and what did you use for brakes?

Very nice.

I spy a Mamba Monster.:intello:

I used Neumotor 1521/1Y (1577 rpm/v) and a Mamba Monster with 2 x 3s zippy lipo 5000mah.
The brake is the esc brake.

I really like it! Awesome!

You Sir are my hero! I love it! One of the top 20 builds on this forum IMHO.

Well done. Very simple yet effective chassis. Love the use of a Neu 1521. This would have also been the perfect motor choice for my custom Baja built. What does your custom Baja wheigh with/without batteries?

Did you use the hexes of the Savage 5T to be able to mount Baja wheels? Could you wheigh the rear (and front as soon as you have it) baja wheel with Badland tire? I'm curious how much more they wheigh over my truggy wheels and tires.

What did you do to lengthen the front middle center cvd / Drive shaft? Got any pictures of your drive shaft assembly? Any issues with the length? Did you a steel tube?

Now that i see your paint job i think i should have also limited myself to 2 colors.

Thank You everybody for compliments...I'm so happy knowing you like my project. :lol:

For Othello:
I get inspiration from your baja project also! I like your work and videos!

My baja RTR with savage bowtie and 2x3s zippy lipo 5000 mah weights 6,7 kg.
A 3s 5000 Zippy lipo is 412 gr, so my baja without batteries should be about 5.8 kg.
One Rear Baja wheels plus a badland tire is 480 gr., while a savage bowtie (rim + tire) is 212 gr.
I will weight also front complete wheels as soon as I will receive front bowtie tires for baja.
Anyway the estimated weight RTR with 4 baja wheels should be about 7.6 kg.
To make front drive shaft I used an aluminum tube with a real cvd cutted at half and inserted an half in a side and an half in the other side of the tube. I drilled the tube and the cvd, then I locked the half cvds in the alluminum tube with two savage hex pin.
I would also close the chassis in front sides with two light carbon carters.
Anyway, I want to remake the front cvd in steel because alluminum tube is too smooth.
To be able using original baja wheels I made 4 aluminum adaptor, but I want remake them in steel too.
I searched for Savage 5T hex, but I did not understand if they are good for my use. Do you know HPI code for them and if I could use them also if I mounted the savage 17mm hex kit?

Sorry for my English not so good, I hope that I wrote is understandable. :oops:

Your english is better than many that grew up speaking it. :smile:
I wish I could communicate in more than one language.
It is great to have you here!

-Zack

Thank you Zack, I love write in this forum and is also a great training for my english :yes::yes::yes:

The baja wheels have a 24mm hex. The savage 5t has not been released here yet, and I am not sure if it will be released. HPI made 24mm hexes to allow the use of the baja beadlocks on the savage, but I do not think they are available yet either. Best thing I can think to do would be to get the easily available 23mm hex adapters for the savage and wrap some .5mm shim stock around the hex to bring the overall diameter to 24mm, use some epoxy to hold that stock to the 23mm hex and you would have a sturdy 24mm hex. I will have to weigh the beadlock/tire combo that I planned to use on my stretch savage project. I plan to use a std MT size beadlock (such as the popular maxximizer beadlock) and moab xl tires. I will have to cut a section out of the tire and glue it together to get the inside diameter to match the diameter of a MT wheel (since the moab xl tires are designed to go on a 40 series wheel). I am doing this cause I like the width of the moab xl, and want a tire with a taller sidewall (and taller overall height) than a std M tire can offer. Plus the ratio of wheel diameter to sidewall height will look more like a corr truck's stock tires (as I plan to put the 5t body I have on this creation).

Anyways, I really like your truck gyn77. It gives me more desire to finish my various large scale projects!

Very nice! Makes me want to start one of these!

I also thought to buy 23mm hex, but the problem was that I cannot replace the same Front Width 18.1" (460mm) and Rear Width 18.9" (480mm) of baja because savage braces are not so long as baja braces.
So I thought homemade adaptor was the best way.

Simple and effective at its best. Many engineers should follow the "Simple and effective" theory. A lot of the good set ups I've seen are simple. Good job.

Thank you Lutach! :lol::lol:

Very nice chassis design there. Like others have said I really like the KISS method as applied there. This makes me want to hack up the LST2.

Good point, I was looking for equal track width on my 5t so that should not be an issue.

Nice ride, how long have you been working on it?

what kind of motor temps do you see on the 1521 pushing that 7kg baja? and what is your gearing?

looks great by the way. just wanting to pick your brain to gain as much info as i can for projects i am doing/planning to do.

About a week (3 hours/day) for planning and making the chassis and a complete day to assembly and adapting all the other parts. :lol:

Neumotor 1521 got 67 C° at max after strong use on grass/dirty/stones and external temperature of about 30 C°.
My gearing is: spure gear 47, pinion gear 14 with center differential.
I want to see how it will get hot with bigger original baja tires.

67 degrees Celcius is about 150 Fahrenheit, that's a perfectly acceptable temperature for a motor at the end of a run. Good job!

Thanks for wheighing a baja tire/wheel. 480gr is more then i expected. A complete set of Baja tires should wheigh around 1800gr. That's about double the wheight of a 1:8 monster/Truggy tire set. Acceleration will suffer, amp draw will increase and runtime will be less. Hmm ... i would also have a smaller trackwidth with baja wheels as they seem not to provide enough offset compared to half offset truggy wheels. And the 24mm hexes are another story. I never saw those savage 5t hexes for sale. Guess i will stay with truggy tires. But i'm really interested in your "practical" results while running those "original" Baja tires.

Concerning the long center drive shaft. After my last run i spotted a place where the aluminium tube started to twist. I will also rebuild it. I think the easyest way is to replace the aluminium tube with a steel tube ... this should provide enough strenght.

I also thought about closing the front sides. Should provide more protection for the electric components and the center gears.

Awesome build Gyn! :great: Someday I'll get into 1/5 myself.

On a different subject- Some of you need to read the thread before you ask questions........ :grrrrrr:

From a technical point of view, this chassis must have very little torsional stiffness. To change this, you need diagonal beams or plates (e.g. CF with bolts in all four corners) connecting the four main beams. Anyway, you've built a nice vehicle.

Today I have received front baja tires. I had choosen bowtie tires to have front grip because my baja is 4wd.
The baja now weights 7,6 kg in RTR conditions. This is the real weight mesured!

Testing the baja with original wheels in my home with the same pinion (14t) used before with smaller savage wheels, I don't see any cogging, mamba monster is great and smooth and neu 1521 is very powerfull, but I will use 12t pinion and get estimed max velocity of 95 km/h!
I remade the front cvd using an alluminum full tube instead of empty alluminum tube. Now it seems to be more strong but I have to try it to see if it is strong enough.

You know what, I am so sure now that the standard 17mm hubs are stronger than the 23mm units. The 17mm's hold the axles better and spread the load out pretty good on the axle. A 23mm on the other hand, causes pressure points on the axle, causing higher stress... plus they wobble alot more than a 17mm.

I am not sure this helps you though?

Sweet build gyn! Makes me want to do a 1/5 project :yes:

Very cool project.

Here a photo of my baja with baja wheels and tires. It is juge!

http://lh3.ggpht.com/_GS-R7ugwb24/Sp...2092009232.jpg




Now I am thinking putting 2 super light alluminum carters instead of carbon one because I already have light alluminum sheets at home. The effect will be similar this:

http://lh5.ggpht.com/_GS-R7ugwb24/Sp...2092009234.jpg

http://lh3.ggpht.com/_GS-R7ugwb24/Sp...2092009237.jpg

When those tires get shreaded, you should look into Hostile tires. I have Hostile Nightmare MX rears on my real Baja and they're great. Hostile makes some of the best tires on the market for 1/5th.

I will do it!

Can't deny that baja tires with around 170mm diameter do look way better then 145mm Truggy/Monster tires. Especially the 80mm wide rear tire. I understand that with custom built (wider) Hexes you were able to maintain a front width of 460mm and a rear width of 480mm now that you have mounted those wheels with smaller offset? Maybe you could post a picture showing your custom hexes.

Using an aluminum shaft should pe plenty as CVD extension. Which diameter did you use?

Post your results after you drove it outdoor. Grip at the rear axle must be tremendous with those wide Badland tires.

Sure, in this evening I will take a photo of my homemeade hex adapter and then I will post it here.

In the photos with big baja wheels, I used my homemade wide adapter.
The front track width is perfectly 460mm, while the post track width is 490mm, 10mm widther of original hpi baja post track.
However, I'm thinking to reduce my homemade hex adapter to stress less the bearings in the Uprights that will be stressed enough from very heavy baja wheels.


On front cvd I used 8mm alluminum shaft diameter, it seems to be strongly enough at torsion and flexure, not as a steel but better of alluminum tube I used before.
I made it in alluminum again because was the fast way, if it will not work good, I will do remake it in steel to a guy that works with metals and has a big lathe and a CNC.

This is a photo of my handmade alluminum shaft 8mm cvd (sorry for image quality):

http://lh6.ggpht.com/_GS-R7ugwb24/Sp...3092009239.jpg

This is one of mine homemade hex adaptors for baja wheels.

http://lh5.ggpht.com/_GS-R7ugwb24/Sp...3092009241.jpg

Thanks for posting the last pic. Won't be an easy job for the bearings holding the axle in place.

Today I went to a park near home and tested the baja with new wheels.
On dirty/grass/stones and external temperature of about 32-33C°, motor temperature was at max 75 C°.
My Baja with neu 1521 is very powerfull!!!! :lol::lol::lol:
Today I was alone, so I have not video of running but only these new photos:

http://lh4.ggpht.com/_GS-R7ugwb24/Sq...4092009244.jpg

http://lh4.ggpht.com/_GS-R7ugwb24/Sq...4092009249.jpg

http://lh6.ggpht.com/_GS-R7ugwb24/Sq...4092009256.jpg

http://lh5.ggpht.com/_GS-R7ugwb24/Sq...4092009263.jpg

http://lh6.ggpht.com/_GS-R7ugwb24/Sq...4092009266.jpg

http://lh4.ggpht.com/_GS-R7ugwb24/Sq...4092009272.jpg

Nice job gyn, you'd be hard pressed to tell it apart from a gasser. Looks great!