CD's for the savage?
 

Hi guys,

Tried to update my old build thread with the question but didn't really get the results I was hoping for.

Thus I'll whip up a thread of its own for the question.

Which CD's are fit for a Savage? Pros, cons, cost, availability, range of spurs available, etc, etc... :)

The one Ive come across quite often is the ofna spider... but I cant find it on ebay and I cant really see which spur gears it can be fitted with?

What about some of the other CD's? Losi 8ight CD? Jammin X2CR Pro bla bla? others? Could a few of the "pro's" please shed some light on the subject for a poor guy who have never played with 1/8 buggies :)

Cheers!

Ofna spider availability seems a bit low but it has the strongest internal gears. I'm using a Slipperential atm which I don't recommended for a Savage as the slipper part isn't really up to it.

Looking to try a Vorza\Hot Bodies CD which i bought fairly cheap on ebay. There are a good range of spurs available for it, I have a Hellfire 52 tooth lightweight spur on it.

I saw that you posted about an Ofna center slipper. I'm really starting to think that i don't need\want a slipper at all in the center and they always seem to be troublesome. I have the slipper locked up on the Slipperential atm and using Ofna silicon diff lock fluid in it. This provides a near locked up CD driving experience but when landing on one end on power allows some power to the redistributed to the other end of the truck instead of instantly shocking the drive train. No drive train breakages for me yet.

Roger roger! I hear what your saying about the slipper ;)

not a bad idea with the hellfire spurs... 51-53 tooth spur could work just fine with a 1600KV motor :) But will supply last? seems the Hellfire is discontinued.... Hmm ok the Trophy 4.6 has a 50 tooth spur. Still a few more wopuldn't hurt.

Thank you for the info DV

Have placed a bid on Ebay for a Vorza CD.

The CDs from different suppliers are interchangeable right?

The reason why I ask is that one of my colleagues whom are producing alot of CNC parts for the projects would like to join me in the hobby... thus I think there is basis for some slighly more advanced custom parts than what I have been able to whip up on my own! But Id hate to ask him to make something fancy for the Vorza and then find out that the Spider or one of the Torsion versions is what we really need/want ;)

Another part Id love to try making with the CNC is the "wide knuckle" I was asking about in another thread...

Not necessarily, no. You'd have to get a bunch and do measurements. Now the Vorza diff is used in the Vorza, Hot Bodies D8/D8T and most of the Stadium line from Hot Bodies. The ring gear even works with the HPI Savage X diff cups. Think the Savage X diff internals are the same as on the Vorza/D8/D8T/Stadium but not 100% sure as they have different part numbers.

But the diffs out of my RC8T are slightly different size to diffs in the Savage X.

As a note, they bearings are probably the most important part though really as far as mounting the CD goes. The length dimension may differ slightly but the vehicles I've dealt with have the same outside bearing size (Savage, RC8/RC8T, Stadium and D8 diffs); believe they are all 8x16 bearings.

What is the point? Yes, the XL axle and other extends place more load on the outside bearing, but it fails just replace the bearing. I suppose you could construct a "wide knuckle" that actually extends the wheel out farther, but thats just really increasing the width of the track, which is helpful, but doesn't increase the suspension travel at all either.

Too bad about the CD's... but hey then I stay in the HPI family ;)

The point is to have less vibration given the smaller angle of the vibrating axle. I know that I could change bearings at a regular basis... but whats the point if I could have fun constructing something better over the vinter?

Go for it then! :) Better though would be new longer suspension arms!

Im going, Im going ;)

My toolshop buddy started dreaming outrunner direct drive to the diff's today... any motors fit for a Savage XL conversion of that sort (with all of the odd ends it has - rollout, cogging, lack of gear adjustment when you swap wheels etc...)

Im thinking that the OKhobby/infinite 1/5th scale ESC could be an ok HW ESC choise? At least the voltage is ok ;)

For my own Savage I am still going with the CC-Neu 1717 and a CD...

Do a search in the forums, I do believe someone did a outrunner direct drive conversion either with the Savage or a truggy.

Ive done the searching.

Something like this: http://hobbyking.com/hobbyking/store...idProduct=2097 on 8s should hopefully be able to opperate in a Sav XL size MT. Will not go for wheels bigger than stock flux.

I was just wondering if there was a new kid on the block providing better motor options for a direct drive Savage than the hobbyking? :)

Will follow the OKhobby 5th ESC thread in the brushless forum.

I believe
 

Yea I believe either SSSconcepts, Sikeston, or maybe Lincpimp have done outrunner direct drive projects in the past few years with some level of success. With so many choices in brushless motors now I don't really see the point of using an outrunner though. Unless you just have one laying around and want to use it in something. The CC 1717 should do just fine if your looking for ultimate power. Good luck with your quest.

Ended up with a HB Center Diff... seems to be identical to the HPI one (surprise...)! Spurs go up to 53 which gives alot of room for gearing adjustments :)

Only worry I have is that the housing looks like plastic!? Hope its black anodized (or how you spell that in english) aluminium.

Will construct the mount a bit assymetrical to get the 1717 as low in the Chassis as possible.

************************************************** ****************

The outrunner direct drive project is my colleagues. Would like to go high voltage / low kv. I suggested this motor: http://hobbyking.com/hobbyking/store...idProduct=2097 and the okhobby 1/5th ESC... then he could run 40-45 on 6s and 65ish on 9s ;)

He has some pretty good ideas for a transmission "shock absorbtion system".

By the way... wouldn't it be possible to have reverse with a cluth setup? Hmmm but you cant motor brake... right? Not a good idea.

No, its plastic. You can use a Savage X diff cup instead though.

Keep this updated, I'm wanting to put a CD in my DB17. I hate how bad the savage drives compared to my buggy and truggy.

Will do... just waiting for bits and pieces to arrive from the US chop shop to Denmark :)

My toolshop buddy began the wide knuckles... made a true wide knuckle for the front and a wide hub+knuckle for the back to eliminate the tie rods and slop in the rear end.

Sounds like I should get an IRC cup for the CD btw? http://www.innovative-rc.com/lightni...ver-p-209.html

Im debating if I should try to do something like the KD direct drive with a CD or mount the motor like Jahay on the side of the TVP. The later seems really easy to adjust.

Also I am debating if I should try to fit 1717, CD and 2x5800mAh Tunigys within the standard XL TVPs, go with larger TVPs or alternatively settle with battery boxes and the weight adjustability they bring to the equation...

Updates when I have progress to show or questions to ask :)

Keep on truckin!

Look at FLM's forward tranny XL chassis; I'd ask about max. size that would fit in the battery area and it was 4S and 5S or 6s was really dependent on size of battery.

Not sure how Jahay is stuffing 8-10S in his Savage, but I'm having enough issues putting 6S in my 5th scale conversion as I move to a center diff and thats only using a 1520 can.

I was working on a CD for the savage that would fit the original housing, in fact, i have the drawings ready.. Just need to find some time to make one. It used the standard size diff-cup.

Savage XL wide rear Hub/knuckle/whateverthenameis prototype:
http://www.rc-monster.com/forum/atta...1&d=1299586662

Close up:
http://www.rc-monster.com/forum/atta...1&d=1299586662

This increases the distance between the two bearings. Which hopefully will decrease axle vibration/wobble and bearing wear.

Been debating back and forth with myself :)

Do I really want to fit all of this in between the TVPs:
http://www.rc-monster.com/forum/atta...1&d=1299587267

The batteries could sit at the back... but they would sit a bit high for my liking (COG issue) and the truck would be arse heavy:
http://www.rc-monster.com/forum/atta...1&d=1299587268

In a battery box the balance of the truck would be easier to adjust. Further more the batteries could sit lower... battery boxes it is:
http://www.rc-monster.com/forum/atta...1&d=1299587268

The 1717 and 52T CD can be implemented off axis in order to allow for a slightly lower motor positioning. It will sit at the same height as a Flux... but with a CD :)
http://www.rc-monster.com/forum/atta...1&d=1299587268

The only thing Im a bit annoyed about is the need for a custom dogbone. I really do not like to have "wear" parts which are custom work. Working assumption is to use the standard XL rear Dogbone in the front and do a custom dogbone for the rear.

Guess Im ready to hit the workshop :)

Looks nice, but still leaves you with a poor axle design. Why not go with an LST2, 8T, RC8T, etc. axle/cvd setup if you are going to the extra effort?

And I would say just use the battery boxes. I have enough trouble trying to get a CD, batteries, motors to all fit in a stretched 5T custom chassis that I can't imagine trying it in a XL chassis.

Might want to look around for dogbones. Might find something thats the right length.

Maybe im just dense... but whats the big problem with the XL dogbones? I havent broken one yet... yet!

Also... if the dogbone/CVD is beefed up to bullet proff... something else will fail instead. Id prefer to have a dog bone as the weak link. Am I missing something obvious?

Nothing, I didn't mention the dogbones, rather tha axles. Axles are poor design given where the pin is located. Perhaps with the extended bearing support you won't snap the axle as much where the threads end; thats where I've always snapped my XL axles. Maybe its cheaper to replace the axles.

Checked your build thread... I see what you mean ;)

Still your running a rather heavy truck with pretty heavy wheels. The XL was designed to run with Terra pins at worst. Hopefully the axles in my XL size conversion with 40 series mashers will be ok :whistle:

After toying with the different parts today trying to figure out a feasible setup with regards to weight distribution (CoG and front/rear) I realized that my biggest problem with this build is the swizz cheese standard TVPs. Im missing material in the wrong spots! So I contacted a new Euro RC custom products supplier and got a quote for XL TVPs with no cut outs. Only holes for bulk head mounting pre made.
Initially I figured Id go with 5mm TVPs and cut them low to enhance the low CoG layout... but it turns out Alza can also supply them in 3,2mm carbon fibre... what to do :)

Well I had some issues with some 40 series Big Joes on my nitro XL too; however they are running heavier 40 series beadlocks, but I don't know that the wheels are too much heavier than non-beadlock wheels.

I'd go with 4mm... save some weight ESPECIALLY if you aren't doing any cutouts, those are bound to be heavy at 5mm. 5mm in the 5th scale build just has been overkill. :)

I'd base any design off the Flux chassis plates not the Savage X/XL plates. The Flux has a low CoG built in anyways.

Yeah, nice you found someone that will do things for a reasonable cost and actually respond to customer queries.

Nixpus, check my build from last year. Batteries in the back are fine, my weight is almost perfectly centered and the truck flies like a goddamn arrow. I actually found a slight bigger battery (5000mAh 6s) was better in my truck to give it a touch more rear traction.

All my stuff fitted in between the TVPs but the 1717 might make it difficult.


Who makes the rear wide hub? Will there be one for the front?

The wide hub will be made by my tool shop colleague. A wide front knuckle is also in the works. We'll only be doing two sets... but the idea is free to copy :)

Im still messing about with my ultra low CoG layout... might do cut outs in the TVP's to have the batteries sit horizontally just above a wide skid plate.

I actually think I could fit the 1717 in on the side of the servo like you did. Not a bad idea! The motor mounting is also smart... but may take too much space.

Here At us in Moscow that creates the people
http://forum.rcdesign.ru/f27/thread219012-16.html
http://s016.radikal.ru/i337/1103/2d/fa8503039948t.jpg

Not bad Berserk :)

Cant understand a word on the Russian forum but there are some nice pictures!

With my current layout the motor sits in the back and thus I fear the truck will be rear heavy unless I mount the batteries in the front.

Id still prefer to do a wide skid plate and have the batteries "side down" on each side of the front dogbone... but if it jacks my weight distribution I'll have to mount battery boxes up front.

So question for the pro's... is the flux battery boxes ok or should I aim at another brand or make some myself?

Me too
 

Yea me too. Love the videos, which helps when you cannot read a word of what is being shared. That truck seems to have plenty of power, and half decent handling, but the tires need to be taped to reduce the balooning effect. Looks like a fun vehicle. Was that a CC 1717 being used in there? What ESC was that?

Greetings
Guy RuslanG is engaged in the basic working out and frame manufacturing.
At present In photos last version under drawings and the first in metal.

ESC MMMv5
The regulator altered on this method
http://photofile.ru/users/berserk80/96565786/
Such variant is named "inverted"
The development beginning in this direction so-called Karabelnikov ed esc http://forum.rcdesign.ru/f27/thread1...ml#post1404006
http://forum.rcdesign.ru/f27/thread1...ml#post1411973

Basically it is made for Truggy Buggy with a horizontal plate.

RuslanG with completions has applied this variant of alteration esc + has added the radiator.

Motor mount under way... still need some support between the two parts :)

Alza racing delivers:
http://www.rc-monster.com/forum/atta...1&d=1300780233

Hmm... with a skid plate and some sort of dogbone protection the batteries could be squeezed in between the TVPs. Motor mount was made with a centered 1717 since this allow me to push it further back.
http://www.rc-monster.com/forum/atta...1&d=1300780233

On the other hand... a wide skidplate and a cut out in the bottom of the TVPs = batteries mounted low and horizontal:
http://www.rc-monster.com/forum/atta...1&d=1300780233

Where will the steering servo go with the batteries up front?

Interesting idea about the cutout in the bottom of the TVPs. If the batteries were up front they shouldn't cop much abuse there. I've been toying with the idea of mounting a battery sideways above the center driveshaft. Could move it back and forth to tune the balance as there would be plenty of space.

With the batteries "inside" I'd have to make a cut out in one of the TVPs, flip the steering arm 180° and mount the servo on the outside.

Its safe to say im leaning more towards the cut out approach... especially after I got the solid TVPs from Alza :)

How much were those TVP's? I've been thinking about making my own, but out of 3/8" lexan since its easier to cut than metal.

very nice!!! im happy to see that dejan at alza is getting more custom now!

Interested to see how this turns out...

IMO i would like to see you widen the internals of the chassis, and fit the lipos either side of the rear shaft.
I like the idea of moving the steering to the outside too!

Are you going to make the necessary cut outs yourself?

Im not really sure how much details regarding other rc sites we are allowed to post here before the board police pulls us over?

Heres the quote I got from Dejan:

plain plates without cutouts and holes (besides bulkhead mounting holes). The weight is for 2 TVP's:

Carbon 3,2mm 280g XL TVP's 60€
ALU 3mm 480g XL TVP's 25€
ALU 5mm 760g XL TVP's 30€,

Hope I didn't step on too many toes there? Anyway, if you have questions regarding Alza racing I suggest you shoot dejan a mail. He seems like a nice guy and is really fast at communicating as well as producing the parts.

The rest of the custom work I'll do myself. Straight cuts and hole drilling should be manageable :)

A little prototyping progress...

Cardboard TVPs with cut outs and batteries:
http://www.rc-monster.com/forum/atta...1&d=1300894939

I need some sort of end stop on both sides of the dogbone. There must be a U profile with the right dimensions somewhere!
http://www.rc-monster.com/forum/atta...1&d=1300895094

Servo can sit in its normal spot (more or less):
http://www.rc-monster.com/forum/atta...1&d=1300894939

Battery placement in relation to the dogbone (vertically):
http://www.rc-monster.com/forum/atta...1&d=1300894956

Ive got 1cm of 3mm thick alu on the bottom side of the TVP cut out at each end of the battery as it is. I wonder if its safe to go even lower? Damn I should have taken the 5mm TVPs! :whip:
If I could go lower it would help servo mounting... still for my friends inrunner project we need a different servo placement anyway. Bright ideas are welcome :)

Because this is the stuff we need to fit into the construction:

The fat outrunner:
http://www.rc-monster.com/forum/atta...1&d=1300895785

9 LiPo cells (its not the packs we'll use but you get the idea):
http://www.rc-monster.com/forum/atta...1&d=1300895785

Its slightly crowded at the backend where I have CD and 1717:
http://www.rc-monster.com/forum/atta...1&d=1300895785

We'll most likely have to do a cut out in the "bulkhead plate" otherwise the angle between the drive cups will be extreme... more fun challenges :)

I was planning on doing my 5T plates with the batteries cut out in a similiar fashion. My biggest concern was protecting the batteries from damage on the sides.

As for the 1cm... if you have a bottom plate that ties together the sides underneath the batteries, that should make up for any weakness in the TVP itself.