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Old 11-12-2011, 06:53 PM   #101
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It'll work.
That's golden!!! exactly what will beaf up the drive line!!!
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Old 11-12-2011, 09:37 PM   #102
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Looks good!

So, what did that take to get them to that point? Think that will work with the stock tubes or did you have to use the max tubes for the bigger bearings?
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Old 11-13-2011, 01:45 AM   #103
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Looks good!

So, what did that take to get them to that point? Think that will work with the stock tubes or did you have to use the max tubes for the bigger bearings?
The only way to provide a strong enough boss for the CVD stubs was to go with the 8mm ID bearing.

I'm done with the stockers. They are the only parts on the whole rig that have less than precise dimensions. I'm still convinced they are pulled before proper cooling... they are the thickest parts, and no one made a mold that was intended to curve the tubes forward and down. They remind me of a tapered candle that saw one too many hot days.

The stock 6mm bearing at the inboard end is used as a carrier only. It serves only to keep the axle aligned in the spool, and when properly aligned will be fine. The rest, you can have.

If you just put a hollow transaxle together, and look through it... it's problem is obvious. The M/M setup is like bore sighting a gun. I cut the fit to nearly interference... they press together by hand, but cannot be smoothly clocked without either using wrenches or lubing the stubs with mold release. When you spin the assembly, all you feel is bearings. Silk.

Up soon is custom knuckles so any CVD can be used. I'm going to try some camber, and high steer. I agree with A... this thing is worth a serious look into it's potential.

edit: Driven Case(Right) 2P I'm gonna cut what I have, and move on. This means there is 1 set spoken for, and 1 set up for trade. The rest is mine!

Last edited by ekd; 11-13-2011 at 05:47 AM.
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Old 11-13-2011, 10:15 AM   #104
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Okay give some more info on the cv's. What are they and what are you using for bearings. Looks like the diameters are different and the only part that is mad torque is the gearbox.
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Old 11-13-2011, 12:45 PM   #105
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Phat, check out post #17, 39, and 85. It's all laid out there.

I'm using Savage CVs, but with custom knuckles, anything should work.

Last edited by ekd; 11-13-2011 at 02:42 PM.
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Old 11-13-2011, 07:40 PM   #106
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Can someone pls tell me the ID of the Axial AX10 Cs?
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Old 11-13-2011, 08:52 PM   #107
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Exactly 12.5mm.

I've got the entire C-Hub digitally modeled from when I was designing these:



If you need any other dimensions, let me know.
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Old 11-13-2011, 10:02 PM   #108
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Thanks, man!

Is yours still apart? I'm having a ton of fun with mine... and haven't charged a battery for ages.
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Old 11-13-2011, 11:01 PM   #109
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Thanks, man!

Is yours still apart? I'm having a ton of fun with mine... and haven't charged a battery for ages.
Yup, I'm in school full time (14 credit hours) and work 40hrs a week, as well as in a long term relationship, so finding hobby time lately has been difficult.
I've got a few days off from school for fall break so I might be able to get some time to work on it.
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Old 11-14-2011, 08:31 AM   #110
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Guys, how much would almost 60* of steering be worth?

It could happen... I think. When building precision machinery, I always do something uncommon here: Support twin bearings in the center as well as the outer race. It means you have to fit a spacer (between the center races) of equal (or better) tolerances as the bearing's itself.

This not only spreads side loads (thrust) between both (a typical knuckle floats those loads to one or the other), but positively locates the born part, if it has a boss (pin, collar, or nut) incorporated. Smoother, stronger, and more precise.

A double universal joint can go smoothly to about 60*... IF it is supported and located rigidly and precisely at both ends. It would be labor intense, but it can be done.

Could it be worth it?

Last edited by ekd; 11-14-2011 at 08:46 AM.
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Old 11-14-2011, 02:14 PM   #111
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Guys, how much would almost 60* of steering be worth?

It could happen... I think. When building precision machinery, I always do something uncommon here: Support twin bearings in the center as well as the outer race. It means you have to fit a spacer (between the center races) of equal (or better) tolerances as the bearing's itself.

This not only spreads side loads (thrust) between both (a typical knuckle floats those loads to one or the other), but positively locates the born part, if it has a boss (pin, collar, or nut) incorporated. Smoother, stronger, and more precise.

A double universal joint can go smoothly to about 60*... IF it is supported and located rigidly and precisely at both ends. It would be labor intense, but it can be done.

Could it be worth it?

For these things, more steering would always be a good thing, but at some point you have the tires getting into the links and shocks. Double UJ's could be a viable solution, but there's gonna be plenty of custom parts that will probably not be worth the cost for the small number of people that would buy them. I think more people would be interested in just CVDs that can get 45 or so degrees worth of steering.

I think the stock components have at least 10 more degrees of steering with very little modification, and with the CVDs you found, and possibly others, I'm personally fine with the amount of steering we are looking at.

I'd still be interested to see what you have in mind though.
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Old 11-14-2011, 07:05 PM   #112
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There is another consideration as well. The difference between a proper setup and one that just "feels" good... a few thousandths... is the difference between a service life and efficiency that would please a high volume manufacturer, and a device most efficient at destroying bearings regardless of their cost/quality.

I'm possibly on track to making a setup that can be properly tuned for the former, without the builder needing a dial indicator, tweezers, and bag of micro shims. It's been brewing for a while, and after the M/M axles are cut I'm planning to proto it.

As to cost and customer base... who cares? Although it would be fun to see a product compete well, the last thing I want is to go back to work. I paid dearly in sweat and blood to build up a life that can best be summed up in 2 smilies: , and

The last thing I want, no matter who it might impress, is to fight over weak FRNs with a CNC machine somewhere in China.

This would be for us red headed step children.

Got the dimensions of the Axial hex tube ends?

Last edited by ekd; 11-14-2011 at 07:08 PM.
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Old 11-14-2011, 08:13 PM   #113
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Got the dimensions of the Axial hex tube ends?
Do you mean the 12mm wheel hexes? The round boss that protrudes into the wheel part?
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Old 11-14-2011, 08:43 PM   #114
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The bosses for the Cs. I want to see if I can come up with something that will allow using my sub axles in smaller dia tubes.

Now that I know hard numbers, I'm seeing quite a few different CV joints that could be used.
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Old 11-14-2011, 11:37 PM   #115
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I think you're asking about the axle tube ends.... they are round on the Axials and hexs on the Venoms.
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Old 11-14-2011, 11:58 PM   #116
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You're right, J. I was thinking about those on A's rig. Venom.

Axial uses both round and splined, correct?
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Old 11-15-2011, 07:06 AM   #117
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You're right, J. I was thinking about those on A's rig. Venom.

Axial uses both round and splined, correct?
The Axial AX10/SCX10 tubes are round with keys and screw bosses:


The XR10/Wraith tubes are splined but the C's have an angled kingpin:


(images pulled from instruction manuals)

Let me know what dimensions out of either of those you need, I have both C-Hubs modeled.

I'm planning on making the end of the stock tube fit the AX10 C-hub but I might retain some of the splines from the original axle to make sure they are perfectly centered and even on both sides.

Last edited by monkeyracer; 11-15-2011 at 07:09 AM.
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Old 11-16-2011, 12:28 AM   #118
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Thanks.

If you can make room for an 8 x 12 x 4 bearing, I can cut you shafts I'll cheerfully guarantee for life. We could set XR 45* CV joints in with no problem.
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Old 11-16-2011, 08:35 AM   #119
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Thanks.

If you can make room for an 8 x 12 x 4 bearing, I can cut you shafts I'll cheerfully guarantee for life. We could set XR 45* CV joints in with no problem.
Hmm, I might be able to make a 12mm bearing work. It would only leave .25mm around the bearing to seat the C-Hub though. The other option would be to look into 8 x 13 x 4 bearings (probably harder to find though) and capture them by the c-hub with the end of the tube.
What about going smaller than 8mm? I think 7 or even 6mm would be fine, and 6 x 12 x 4 bearings should be easier to find.


My idea was to get something like these:

Front Universal Drive Joint 2P

And cut off the ball end, and extend the shaft to the correct length. It would be about $40 for all 4 axles to do this. These would give us at least 45*, but probably more. But I want to see how much I can tweak out of the stock as comparison.
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Old 11-16-2011, 09:25 AM   #120
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If you use a 6mm bearing, the walls of the socket would be thin. I'm not sure they would hold up. At 8, with my 4.5mm Savage CVs, they are stout.

7mm bearings are probably as small as the design can help with.

You could turn the ends to fit just the ends of the Max tubes. It's almost too easy... but, you'll still have that curve.
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