brushless 1/5 4wd conversion about to begin! couple questions.

if you still wanted a center diff,what about making a mount for the baja diff,then using an idler gear of some sort to get the pinion to it.it might also offer some more gear reduction if needed.just a thought...

[Ryu James]

Originally Posted by KaztheMinotaur

The MT gasser with those HUGH tires weighed 37 pounds! I calculated hte impact force of it hitting something at 35 mph and it came out to around 400 pounds.

I'm currently using a scanner-rc.com servo for steering. 348 ounces at 6V. It is digital and works well for the price of $60. None of the US distributors carry that one so I have to get it from the Canadian distributor. $60 shipped to the US isin't bad though.

What about using this motor? http://www.innov8tivedesigns.com/pro...roducts_id=515 The power seems to be similiar or am I missing something?

that motor is more like the size of a Neu 1515 (14.8oz). i have seen those motors but have never heard of anyone using them. i think my buddies might use those for some budget planes they build.


hey,
does anyone know why this servo says to use NiCD packs only?

http://www3.towerhobbies.com/cgi-bin...XVPF0&P=8#tech

COMMENTS: Use with NiCD batteries only
A note on Coreless motors: Conventional servo motors have a steel
core armature wrapped with wire that spins inside the magnets. In
a Coreless design, the armature uses a thin wire mesh that forms a
cup that spins around the outside of the magnet eliminating the
heavy steel core. This design results in smoother operation and
faster response time.

[Overdriven]

It's says "NiCd only" because they don't want you to use alkalines, but they haven't kept up with the rimes to include NiMh and lipo etc.

Personally I'd run a 1/4 scale servo. The two you linked still have alot of torque and either should be plenty. Also I don't care how big the gears are, there's no way they can be as big as a 1/4 scales, it's physically impossible. And what about the gears in the JR is big, the teeth, dia, width? Usually what happens in standard servos is the gears get wider to increase the contact area of the gears making them stronger. Even though the standard has more torque than the 1/4 scale, the 1/4 has stronger gears so it can stand up to the shock loads that get past the servo saver.

[Ryu James]

Originally Posted by Overdriven

It's says "NiCd only" because they don't want you to use alkalines, but they haven't kept up with the rimes to include NiMh and lipo etc.

Personally I'd run a 1/4 scale servo. The two you linked still have alot of torque and either should be plenty. Also I don't care how big the gears are, there's no way they can be as big as a 1/4 scales, it's physically impossible. And what about the gears in the JR is big, the teeth, dia, width? Usually what happens in standard servos is the gears get wider to increase the contact area of the gears making them stronger. Even though the standard has more torque than the 1/4 scale, the 1/4 has stronger gears so it can stand up to the shock loads that get past the servo saver.

makes sense. thanks for the advice.

[Ryu James]

THE 8MM, MOD 1.5 pinions are avail on RCM now. i ordered a few for the conversion. also, i met with machinist to start on motor mount


http://www.rc-monster.com/proddetail...=rcmbajapinion

[KaztheMinotaur]

So I was thinking...you aren't going to be able to run mechanical brakes that way you have it now. The brake pads ride on 50024 and 50074 which is connected to the D gear on the outside of the gearplate 50011. You have all that removed in order to run a pinion / spur to the center diff...which seems like the best idea.



In this picture the upper gear mounting plate is turned around to face the side that the pipe is normally on.



I think you are going to have to rely on ESC brakes...

[Unsullied_Spy]

Brakes? We don't need no stinkin' brakes!

You bring up a good point. I wouldn't rely 100% on ESC braking when it comes to something with that much kinetic energy, not with modern ESCs at least. I'd set the brakes to 10-20% on the ESC and come up with some mechanical brakes that will work. Running brake discs at the center diff like it's supposed to be will interfere with your gearing options unless you go for some really puny brake discs. I think I'd go with brake discs on the diff input cups or even 4 wheel braking. It'll take some work to figure it all out, but this conversion is going to be worth it.

[brushlessboy16]

I say front disk brakes for a 5b.. not sure on the hex size but they sure do look sexy...

[KaztheMinotaur]

Baja disk brakes will be the best idea. I don't think there will be a way to get pads on the diff cups.

I assume that Dave's has those brakes? Link?

[Overdriven]

Redcat hex is 22mm, baja is 24mm. The Redcat can run the baja rear hexes all around, either way you need new wheels or new brake discs made for the smaller 22mm hex.

Why can't the stock brake be run again? I thought it was in the front of the diff opposite the gear. I guess motor clearance is a concern with the motor mounted up front? Can we get a pic with the stock brake disc in there?

IMO it's time to figure out the target speed and do some math to determine what the size of the gears will be to see what will fit with the stock brake. Unless of course you want to adapt brakes at each wheel anyway.

[KaztheMinotaur]

I have Dark Soul Baja hexs on mine now as I am running Desperado / BowTies.

You can see better pics on the RedCat site: http://www.redcatracing.com/RC-Cars/1-5-Scale-Gas

I don't know if the brake will mount up to the hub carrier.

[lincpimp]

Stock brakes are on the shaft that come off the gear reduction cluster and goes to the bevel gear, so he has that entire assy removed. Either putting disks on the diff inputs, or preferably on the wheels would be the other options.

[Overdriven]

Oh, ok. I was wondering why NONE of the pics had the brake on the center diff! Brakes on the wheels get my vote then. If he's got a machinist to make the motor mount, make some new discs with the 22mm hex in them. I'd think that would be less expensive than machining a new shaft and mount for the center diff to accomodate a brake. Plus brakes at the wheels would be more powerful and fade resistant, important considering the weight of this thing.

[KaztheMinotaur]

Whats the link for that brake kit?

[BL_RV0]

Originally Posted by KaztheMinotaur

Whats the link for that brake kit?

http://integy.com/st_prod.html?p_pro...94&p_catid=126