Frankenstein Build

[mjensen]

Originally Posted by Fricker08

Hey before you scrap the whole project, I know they’re expensive but I believe the vanquish scx10 iii axle housing would allow you to flip the ring gear. Therefore spinning it the correct direction. My buddy has the housings and I asked him, he sent me this pic. Good luck either way man! I enjoy watching your builds



Sent from my iPhone using Tapatalk

Thanks for that. I have a Vanquish F9 on my VFD Capra and knew the bearing carrier/diff could be put in backwards so I figured the SCX10 3 version might be the same. Unfortunately Vanquish wants $242.00 plus shipping just for the housing and then, because Axial uses spiral cut ring and pinions I'd still need to pick up a set that's reverse cut which seem to be going for $35-40 when they're in stock. All that is a bit beyond my budget at the moment.



I suppose I could just buy a set of reverse cut gears for the Vanquish Capra axle and run that since the VFD Capra is in pieces because I took a lot of the mechanical bits off it so I could measure them up for this build. The advantage of doing that is that the pinion in the Capra housing is offset the same distance from center as the !0 3 housing even though it's wider and it's already set up for SOA/4link so I wouldn't need to mess with any of that. If I can find anther set of TGH Capra wheels to keep the width down I might get this thing working for under $100. I need to give this some thought.



Thanks for giving me a little push to rethink the scrapping idea. And thank your friend for the picture!

[mjensen]

Before I got too excited thinking I might have this thing figured out I figured I ought to double check the Vanquish Capra housing to see if flipping the diff would actually work. It won't. You can get the get the bearing carrier and diff in the third member backwards but it hits the inside of the housing when you put the axle together. Probably should have checked that before I ordered the reverse cut gears. This may be the case with the Vanquish SCX10 3 front housing too



I did find a SCX10 3 F9 style housing that looks like it might work. It's a bit overpriced cast metal housing by KYX and the reviews aren't great so I don't know if it would be worth taking a chance on it without knowing more about it. Anyone have any experience with KYX SCX10 3 front axle housing?

[twade984]

Can you install the whole third member upside down? I believe Harley did that in an f9 portal for his portal rear only vs410 pro. It would create a low pinion, but everything would be meshed the same. Low pinion probably wouldn’t be a concern since it’s portal anyway.



https://youtu.be/RZS3i59okq4

[mjensen]

Originally Posted by twade984

Can you install the whole third member upside down? I believe Harley did that in an f9 portal for his portal rear only vs410 pro. It would create a low pinion, but everything would be meshed the same. Low pinion probably wouldn’t be a concern since it’s portal anyway.



https://youtu.be/RZS3i59okq4

The 3rd member on the Vanquish Capra front axle isn't symmetrical like the rear axle is so it wouldn't fit together.


I actually watched Josh's video for his rear portal mod this morning because I was trying to figure out what kind of overdrive issues I'd have if I just stuck an AR45 straight front axle on this truck. He had to grind the upper link mounts off the 3rd member because they are machined as part of it then make some brackets to mount the links. I definitely wouldn't want to start grinding on my axles.


You can flip the 3rd member on the stock Capra axles but unfortunately the front has a center pumpkin so it wouldn't work with the VFD.


Thanks for trying to help!

[mjensen]

A bit off topic but the Harley Designs video that twade984 linked above is really good if you're looking for information on how to figure out final drive ratios and overdrive percentages. Josh goes through the math and explains it really well.

[twade984]

Man what a bummer. One last thought, I saw somebody mention a company that makes a 3D printed rear case for the vfd to allow reverse rear output, only problem is I can’t remember the name of the company! I looked it up once, but can’t find it now. It was mentioned here on rcc.


Sent from my iPhone using Tapatalk

[mjensen]

Originally Posted by twade984

Man what a bummer. One last thought, I saw somebody mention a company that makes a 3D printed rear case for the vfd to allow reverse rear output, only problem is I can’t remember the name of the company! I looked it up once, but can’t find it now. It was mentioned here on rcc.


Sent from my iPhone using Tapatalk

Great! Thanks, I'll see if I can find it. At this point I'm running out of ideas.

[twade984]

Man it was driving me crazy that I couldn’t remember who made it, but I finally found it.

https://seasquirrel.co/products/vp-v...ut-reverse-kit


Sent from my iPhone using Tapatalk

[twade984]

Man it was driving me crazy that I couldn’t remember who made it, but I finally found it.

https://seasquirrel.co/products/vp-v...ut-reverse-kit

[mjensen]

Originally Posted by twade984

Man it was driving me crazy that I couldn’t remember who made it, but I finally found it.

https://seasquirrel.co/products/vp-v...ut-reverse-kit


Sent from my iPhone using Tapatalk

I appreciate you finding that for me. If I'd designed my chassis with a longer wheelbase their mod would be a good solution but with my shortened wheelbase, short driveshaft to the middle axle, and the output on their case being a lot higher I don't think the driveline angle would work. Since the middle axle is a pass through axle feeding the rear axle it has equal length upper and lower links to keep the pinions relatively flat during travel. Right now when the middle axle is at it's lowest point the driveline angle is pretty high. If this were a 4x4 I could shorten the upper links so the pinion would stay pointed at the transmission output during travel but I can't do that with this 6x6 setup.
Thanks for trying to help. If I end up making a 4x4 out of this truck I could use their case together with one of my TRX alxes which would be a lot cheaper that putting together an AR45p rear.


In the meantime since I had already prematurely ordered the reverse cut gears I decided to take a chance on that KYX housing. I'll know in a week or so if that's going to work.

[twade984]

That all makes sense, no worries. This is a cool project and I hate to see it not get finished.


Sent from my iPhone using Tapatalk

[mjensen]

The KYX axle housing showed up yesterday. The description on Amazon was quite vague saying only that it was a metal housing so I wasn't expecting much. There was an identical housing minus the KYX logo listed on Amazon from another Chinese company that claimed the housing was CNC'd aluminum but it was clear from the pictures of both housings that they are cast. I'm guessing from the weight of the KYX housing it's probably cast zinc. Very heavy. The inside of the housing looks like it should be no problem flipping the diff but I'll know for sure tomorrow when the reverse cut gears arrive. Hopefully this will work out.


For comparison I weighed the Supershafty CNC'd front housing that used to be on my Capra and the KYX housing. Huge difference. 2.3oz vs 5.2oz. If I use all the brass I had on the Vitavon axle plus the servo this one will weigh in at close to a pound and a half

[mjensen]

I got the front axle put together tonight. For anyone that might consider buying this particular front housing or one of the other copies being sold by various Chinese companies I'd advise against it. It's cast of an undetermined metal(and not very well) for one thing in spite of some of the companies claiming it's CNC'd aluminum. And the machining, what little there is, is terrible. I spent over an hour with a file, drill, and sandpaper cleaning things up so the steering and axles would even turn. Normally I would return something this poorly made and gotten something else but unfortunately this is only thing I found that had even a chance of working.



Anyway it's working now and turning in the right direction so I can finally start making some forward progress on this build instead of going backwards.

[twade984]

I’m glad to hear the project continues! I had a set of kyx trx6 housings and was less than impressed.


Sent from my iPhone using Tapatalk

[mjensen]

Originally Posted by twade984

I’m glad to hear the project continues! I had a set of kyx trx6 housings and was less than impressed.


Sent from my iPhone using Tapatalk

It's really too bad because the design is fine but the execution is horrible. It would be nice if one of the high end aftermarket companies would make a portal front axle with the same pumpkin offset as the AR45's, which seems about perfect for link and drive shaft clearance on front mounted motors, with a symmetrical diff housing so with the proper ring and pinion you could use it with any rear axles. IE a better version of something like what I used.



Then again maybe there aren't enough people out there trying to put things together that aren't really meant to go together like I tend to do to make it worth while.

[Fricker08]

Man I’m glad you got this together, and it’s spinning the correct way.
I know the trouble of spending way too much time on something poorly made all too well… it is unfortunate but I appreciate the insight about it. Stoked to see where things go from here


Sent from my iPhone using Tapatalk

[twade984]

Originally Posted by Fricker08

I know the trouble of spending way too much time on something poorly made all too well…

Some of us do it for a living…

[mjensen]

It's been a while since I've felt up to doing anything on this build but today I decided to see if I could figure out the cnc router I bought a year ago. A lot of confusing stuff but I managed to grasp enough to cut out some rails that actually look pretty good.
(in the picture I posted you'll have to imagine the other rear rail is there. I ran out of 3mm stock)

[twade984]

That looks great, glad to see some more work done on this


Sent from my iPhone using Tapatalk

[mjensen]

Originally Posted by twade984

That looks great, glad to see some more work done on this


Sent from my iPhone using Tapatalk

Thanks! I got a bit more done today. There's still a lot left to do but at least it's progressing.