drewcrew6

I need ideas for a front hub design that will eventually be 4 wheel drive with 1/2" axles and the truck will weigh about 30-40lbs. I'm not sure if there is anything out there already. I figured I'm going to have to make my own from scratch, as long as the design is simple thats not a problem. But if there is something readily avail that is reasonable that would be great.

Thanks
Drewcrew6

Soloratov

My Feedback: (1)

Drew......been a while. I have a fully designed front hub for my truck all set and ready to go. Mine is 1/4 scale, can't remember your scale off hand, but you could easily modify the dimensions to work for your truck. I think total cost to me...granted I made it myself was about 30 bucks for both. It runs 2 bearings for 3/8 shaft, and 3 ball joints for the suspension and steering.
Now, depending on how the next couple of weeks go, I may actually be scrapping these for a geared hub.......in my original research I overlooked the fact that a real hummer has these, which serves 2 very nice features. It would raise my ground clearance by 2 more inches, and give me a little extra torque gearing at the wheels.

Anyway, if you want some kind of drawings or whatever, let me know, I'd be happy to share.

Pics below:

bsrman14

Remember the weight to hp ratio.

speedy.d

brsman14, WHAT ARE YOU TALKING ABOUT it looks like these fellas have it under control

drewcrew6

Yes Solo it has been. Your front hubs look sweet. For only $30 can't beat that, the bearings alone are close to that. The part with the front hubs is I can't decide how to "fix" the bearings in a housing. Looks like you are using setscrews around the outside? What takes the turning forces on your hubs?
The truck will be quite heavy and will need to take massive stress when bashing it. Right now I have traxxas front hubs by rpm (#80032) and am using those for the moment. They are the strongest I could find at my LHS, they have nothing for 1/5. They are modified to take a 16mm bearing with a 8 mm shaft instead of the smaller 15 X 6mm bearings. I have very little runtime right now as I am having issues with a single part of the drivetrain.

I have been thinking about the rear suspension and have been looking at going to a 4 link. But I have some off the wall ideas on how to implement it just not sure how it will react.

Yes Bsrman I remember. By the way come on and give some more info on your car here [link]http://www.rcuniverse.com/forum/m_8305205/tm.htm[/link] . Wether its alittle more tech info or more pics or video even if it has a body or cardboard covering the areas you don't want seen. I posted over there also.

Thanks
Drewcrew6

Soloratov

My Feedback: (1)

Right now, I do not have any plans for fixing the bearings in place. They are held in the spindle like all the other 1/10 scale vehicles. I have a wall inside the spindle at a depth that is relative to the thickness of the outside bearing, one on either side. They are free to spin, but it is of little concern as they are pressed in, and spinning force is less of a concern than side to side movement. The positive of this design is it allows perfect alignment of the impact joints in relation to my suspension. I know they can take the load as well, as I have sat on the truck and rolled around our shop. I weigh 180lb, the truck is at 40lb, and thats way more than the total truck will weight. Rolled smooth as butter. Even hooked a high speed drill up to the diff I had at the time.......had the wheels roarin, kinda scared me too.
My only concern with those knuckles is that while nylon is tough and can take a beating, under the weights we are talking, I think the linkage area will bend and snap under stress. I have the same concerns even with my aluminum link as it is maybe a little thin, and it stick out a ways, but I will have to test it and see. Either way, let me know, I could modify my design if ou want, send you a cad file or something similar to help you out.....something i enjoy doing. I would just need to know exactly what bearing your going with, how you plan to link the hub to the arms, and then a general size. Don't get discouraged, imagine how I feel knowing I overlooked something and have to redesign a working part.......it sucks.

bsrman14

I can beat that price Bearings .050 x 2, 2 rod ends $1 each x2, aluminum Free. ujoint $15 each or free if you make the yourself. No plastic or steel allowed except for axles!!!

Soloratov

My Feedback: (1)

ok, so....15 for each u-joint......it's 6 rod ends, not 2, so there's 6 bucks, and 4 bearings, not 2, thats 2 bucks, looks like a total of 38. Hmmm good math. Also, figure in the cost of making the stuff, at least a few hours there. Granted I never figure that in if I make my own stuff, just sayin.

Anyway, Drew, one thing I did backwards was design the spindles before I knew what type of drive I was going to have. Having u-joints from an impact socket created one issue in that i need a square hole in my axle. Issue for me because I don't have a broaching tool or machine. What happened was my u-joints created an offset in my drive, and I then had to bury the bearings deeper in the spindle to make up for that offset. Just some caution in that aspect, thats all.

bentley marshall

have you got any pics of how you have set up the drive i the rear ??

drewcrew6

Thanks Solo: The "lip" inside for the bearings to press against is what I was wondering and meant by "fixing" the bearing.

Bentley: Right now don't have any pics as its just some thoughts in my head, currently I have no suspension and just stripped out my toro gearbox with little runtime on it. I think there may have been something wrong with it because my new one feels alot tighter and smoother. I am going to make some braces for the rear cover, I think it might be flexing a little also, allowing to much play in the gear mesh when under load.
I think most that are running the toro's have a shaft drive to the box. I currently have a sprocket on it that is causing sideloading so that might be the issue.

I am just wondering if anyone else has any issues with the toro's that get bashed so far it does not look like they will last unless its my application of it.


Thanks
Drewcrew6

Soloratov

My Feedback: (1)

I think it was QSL, or my old friend Berretta a while back that used those toro's, or suggested them. If I remember correctly people were actually having good luck with it, but I could be wrong. I think you might be right, I know those are meant to be shaft drive, direct connect to the engine, so the chain is probably torquing the input to the side causing binding and drag. Is it the orientation of your engine that requires the chain drive? Should be able to just turn the engine and then a real simple shaft could be attached.

drewcrew6

Yea Solo: It was qs and berretta I believe . I haven't been able to get any feedback on reliability of these. I'm gonna start a thread for this and see what comes up.
And I know that you are better then this just think a bit buddy: For a chain the engine is already inline with the gearbox. Anyway The reason for the shaft is trying this on the original chassis I built and it was the cleanest (mechanically) solution. This chassis is not long enough for something else. I guess I'm gonna bit the bullet and start a new frame to do it right. On the toro they have a pulley on the end so they do take some side loading but the belt is loose and it doesn't take nearly as much torque.

Thanks
Drewcrew6

Soloratov

My Feedback: (1)

hehe, you called me out on it...I know, I was tired and typing what I was thinking....not really thinking about what I was typing. But yeah, belts are usually ok, but those are meant for v-belts right? Not the best at torque....however it should be easy to swap out for a timing pulley. But, you can always follow my footsteps and redesign the chassis. It was Berretta that once told me, design it once, then when things don't fit right, you can redesign it so everything is perfect. Eh, I look at it as all part of the fun and challenge of homebuilts. Lets face it, we are all trying to cob something together from nothing, no way it'll work perfect on the first try.