Project: Savage Flux 5T

[thzero]

I think 8mm is ok, I haven't bent any axles yet. But the Savage axle is just a damn stupid design that introduces a huge weak point at the threads. They needed to have gone standard buggy/truggy style with the axles.

As for the ProLines I think it was two-fold. First, soft material used and poor design by ProLine as their attempts to lighten the hub just made it weak. But yes I agree that the pin diameter is too small and the pin is frankly too short so there is very little area to spread the force on and that was the second part of the issue. The 24mm hex adapters from HPI, although suffering from the poor axle design, are much beefier with a better design. I did run these for a bit, before breaking another axle, and the hubs did hold up.

I do like the Baja 24mm hex adapters as, like most buggy/truggy, its a pin through design with a thick pin so there is a fair amount of area to transfer the force through.

If I could get some 17mm to 24mm adapters I would probably switch to truggy arms myself. My only thought of the truggy arms would be that they are made for racing so will be stiffer, which means they may break more often under extreme bashing than the more flexible Savage arms. I may do this for my nitro/brushless transformer Savage... haven't decided; debating between that and doing a straight axle (using twin-force axles) based MT.

I've been following your LST thread, looks promising.

Originally Posted by lincpimp

Given your experience with std savvy hex adapter failures, and your mod to allow baja adapter I wonder what you think about having 8mm axles in a savage?

Looks like the small stock hpi pin casue the failures on the hex adapters. Just not enough material and the slot wanted to cam off the pin the whole time it was under load.

I see the setup you have now as much better, as long as the xl axles will survive.

I plan to use an 8mm truggy style setup, and hope it will last better under power.

Any thoughts on this?

[lincpimp]

Good info.

I do remember you mentioning breaking the hpi axles. I do agree that the adapters are a bad idea, and the entire axle needs to be changed.

Pity hpi does not make a kit like this to fit the shd dogbones:

http://www3.towerhobbies.com/cgi-bin...&I=LXKZR3&P=OW

Or something like this to replace them with cvds:

http://www3.towerhobbies.com/cgi-bin...&I=LXLHF4&P=OW

[thzero]

Yeah... what they really need to do is replace the Savage suspension and graft on the D8T arms instead. :)

[lincpimp]

They need a wide arm setup with 8mm axle cvds and a better hub design with increased steering throw for the savage. And fixed rear hubs as an option too. And upper arms with turnbuckles that match the wide arms. The could stick with the c hub setup they have now, just some wider hubs with larger bearings spaced farther apart for better load handling.

Can't wait for the cen stuff to come in, looking at the pics and diagrams that really looks like the hot ticket.

[Jahay]

hmmm only time will tell about the CEN parts!

[thzero]

Be interested to see what measurements you get .

From my measurements for suspension width, with the suspension flat on the ground, from outside hex to outside hex:

Savage X: 14.25"
Savage XL: 15.25"
RC8T: 15.125"

I was a bit surprised by this. But on the flip side, the suspension arm is longer so the you should have more suspension travel. Also, the axles and extenders are far more robust than the Savage junk. Unfortunately not viable yet for the build as no one has made any 17mm-24mm hex adapters.

[thzero]

Made some changes. First off, I had to shorten the chassis by 8mm in order to use dogbones that I could find; although I may have found somewhere to do custom dogbones so I may change it back.

If I looked at 3S, or 6S, I could definetly fit doubles within the frames, but would need to have the batteries (obviously with 5 or 6S block; 5S being what I'm running now) positioned over the drive shaft. As part of the process of creating new frames, I wanted to reduce the CoG so was hoping to run the batteries on either side of the drive shaft low in the frame. This meant 3S batteries. There is about 30mm clearance (driveshaft is thicker than the standard Savage) on either side of the driveshaft which is enough for most 3S 40C ~5000mah batteries.

But with the Mamba XL having come out, and having 8S max with motor braking, I wanted the ability to not only run 6S but to also run 8S batteries. After sampling the various 40C or above, 5000+ or above 4S batteries I realized I needed at most 50mm wide area for the batteries. Unfortunately since the Savage TVPs are only 73.75 mm wide from inside to inside, that means that two 4S batteries won't work as most of the batteries were around 40-45mm wide!

So what I did was refactor where I was going to put and mount the batteries. In the forward section, I create two cutouts that leave room for two 3S or 4S to sit on either side of the driveshaft. The cutouts mean that the batteries will extend beyond the TVPs, but that shouldn't be an issue nor should the cut-outs as I plan to use 4.5mm carbon fiber for the frames. A bottom plate, cut out of CF again, will act as the battery holder and as a skid plate of sorts too.

Will need to create some type of guard that surrounds the outside of the batteries and attaches to the TVPs to keep the soft packs from being damaged; either that or will need to construct some battery shells for soft packs or just use hardcase 3S when running 6S.

[toplakd]

I like this design also. More than 5b design. I made one just like that for an Austrian guy. With transmission of course :)
I see also, that you wont need a skid plate as your chassis will be almost completely sealed at the bottom. Nice work.




Dejan

[thzero]

Yeah, this is my build thread... thanks!

Originally Posted by toplakd

If this picture is not apropriate, than let me know and I will remove it.

[thzero]

Well I've been pondering what I want to do with this. I keep wanting to add truggy features to it, i.e. truggy diff cases (D8/D8T/etc), center diff, swapping to diff arms, etc. Not to mention the issues with fitting 8S between the rails. The above solution seems best, but I am just not content with it.

So I began to wonder why not just go with a truggy (my RC8T) to began with. The issue is I really want to run the Baja 5B tires/wheels. But there aren't any 24mm adapters; after poking around I found that Integy, yup the same, makes some extenders for "buggies" and a different couple of options; so I picked them up to see.

First is this.
http://www.integy.com/st_prod.html?p...155&p_catid=75

However, this don't work as when the wheels are added there aren't any threads left to thread the nut on.

Second is this.
http://www.integy.com/st_prod.html?p...31&p_catid=102

Well for my case, they were two wide so the pin wouldn't line up with the hole in the axle.

Third is this.
http://www.integy.com/st_prod.html?p...539&p_catid=93

Ah! They work; almost... had to grind a tad off the end to get the pin to match up, not too much and not where it will seriously hamper things. They are pretty well machined and very beefy, much more so than the standard RC8T axle extensions, but its probably made of the standard crummy alloy Integy uses. The one thing I really don't like is that all that keeps the pin in, and its a standard pin through design, is a large o-ring. I should note that these come with two sets of pin holes, the 3mm for like the RC8T and a slightly smaller set; the pin holes are perpendicular to each other. So these should fit the LST/LST2/LSTXXL, most 8th scale truggies and buggies, plus probably some more. Savage not so much.

These things are wide! From the outside of the bearing to the outside of the hex, the standard RC8T axle extension is 18.75mm. These are 38.5mm. So thats a 39.5mm, 19.75 per side, of extension! Not quite sure I needed that, could use probably just 20mm. Total width, outside hex to outside hex, is 422.25mm.

Here they are in comparison to the standard RC8T axle extensions...



And here they are on the truck... need to pull it apart and get a comparison shot between the two.



Obviously these are 23mm hexes, so need some metal tape to take up the slack for use with the 24mm Baja wheels. The biggest issue is that the threaded shank is only 9.5mm as compared to the 24mm Baja hex hub which has a threaded shank of 12.5mm. So the nut won't fully thread onto the shank. As a reference, the thickness of the wheel is 4.5mm for some ProLine Tech 5 wheels as compared to 6.5mm for the ProLine Desperado wheels. Basically there is about 3.4mm of thread outside the Desperado wheel and the hex nut is 6mm thick; slight issue. Suppose I could grind down the wheel about 2mm; wouldn't be prefect but still.



Now, if I could only find someone who could machine me a set of these, about 19mm shorter, and with 24mm hubs and 12.5mm threaded shank it'd be prefect.

For reference, the pin through design for the RC8T has a pin that is 3mm diameter and 16.5mm long; not quite the 4mm that the Baja uses, but its slightly thicker and definetly longer than the standard Savage pin.

And just some shots with the 5B tires mounted...

[Knez]

Can u maybe provide info about the tire/ rim, front and back?

How tall are tires, what is the weight of the rear combo and front combo?
Dosent look much offset by the rims alone?

How do u like them?

[thzero]

They are Baja 5B tires/wheels; specifically the ProLine Badlands tires and Desperado wheels. Somewhere in this thread I believe I provided the weight. None of the wheels I've seen for the Baja 5B, I haven't looked at the truck wheels as I think those are just too big for an 8th scale platform, have any offset. But as an FYI, neither do the 3.8" Trenchers.

I like them for a large "buggy" platform because they have a low sidewall, so it drives more like you'd expect a buggy to as opposed to say a monster truck.

Originally Posted by Knez

Can u maybe provide info about the tire/ rim, front and back?

How tall are tires, what is the weight of the rear combo and front combo?
Dosent look much offset by the rims alone?

How do u like them?

[Jahay]

Originally Posted by thzero

They are Baja 5B tires/wheels; specifically the ProLine Badlands tires and Desperado wheels. Somewhere in this thread I believe I provided the weight. None of the wheels I've seen for the Baja 5B, I haven't looked at the truck wheels as I think those are just too big for an 8th scale platform, have any offset. But as an FYI, neither do the 3.8" Trenchers.

I like them for a large "buggy" platform because they have a low sidewall, so it drives more like you'd expect a buggy to as opposed to say a monster truck.

I have been desperately looking for an ideal tire for the savage... I wanted to maintain truggy handling... and like you said, it is important to keep the side wall low. Yes those trenchers are huge but the side wall is massive! I HATE ROLL OVERS!
i think the proline baja tyres are great! (people dont like them on heavier bajas as they wear quickly, but they should be perfect on the savage)... also with the powerful brushless systems, there isnt a worry about moving these tyres and i believe the heavier wheel/tyre combo def gives more stability at speed...


edit

just had a re read of your entire thread! I love how you have tried to play around with the truck so much!!!
You are going the CEN arm way, and i have tried the LST Arm direction... We can compare which hubs work best with these tyres haha
What do you think?
Also with your experience with your tyres, how have you found them in corners? do they slide a little or is there so much side bite that they grip and force you to roll over?

[thzero]

On asphalt it does have a tendency to roll over in sharp cornering. But I attribute that to the higher CoG on both the TVP design, the higher placement of the motor in the Flux TVP design, and the batteries being over the driveshaft, and a bit with the width of the truck even with XL axles.

Offroad I've really had no issues.

Originally Posted by Jahay

Also with your experience with your tyres, how have you found them in corners? do they slide a little or is there so much side bite that they grip and force you to roll over?

[thzero]

Since I'm looking at turning my truggy into a 5th scale (mostly because I found myself trying to truggify the Savage so why not start with a truggy intead), I turned by Savage back into a standard sized Flux to run on 4S (for now); got one lid painted up and this how it ended up...



Some non-standard features...

TCS Crawler TVPs (until I decide what I want in custom carbon ones to fab up)
ProLine Trencher tires on Tech 5 wheels (love the look of these mounted up)
Integy rear-hubs
FLM Drag Link (http://www.fastlanemachine.net/prodd...lm48000&cat=22)
FLM Skid Brace (http://www.fastlanemachine.net/prodd...lm47500&cat=22)
Spektrum DX3S/3100R transmitter/receiver
Running 47/19 ratio (may go up to 47/20... if I want tons of speed, I can whip out the truggy)
HD Drive Gear 18-23T (102514)
Yellow springs and 50W oil
Modified steering hubs (see further up this thread)

Will be looking at swapping to using truggy-style hex hubs instead on modified XL axles. Also when I rebuild the diffs I'll swap to using the Vorza/D8 cups and HD internals.

May eventually put a 1518 (my 1520 is going in the 5th scale) with the GCM 42mm motor mount.

This is just planned to run on 2S or 3S; nothing too wild.