RC10 Buggy but 3D printed

[Oblivious1984]

Another update for everyone - I've continued to have success with tapping different parts for mounting. The nose arrived so it's starting to actually look like it could be an RC car now.

I noticed that the shocks that I got seem to be too long for the car. The eBay listing specifically said that they were meant to fit an RC10 so I'm a little unnerved about that. Anyways, I don't have enough parts ready to truly mount and test them so I figure the worst case scenario is that I go to hobbytown USA and buy some new shocks.

As it turns out all of the LiFe batteries I have access to are much too large to fit with the setup in the way that I want. To solve this, I will probably end up buying a LiPO battery for the job.

Here are some photos of the progress:

[juicedcoupe]

Never trust ebay listings.

Many will attach words like RC10, Tamiya, and Kyosho to random parts in order to generate more search hits.

[XLR8]

...
I noticed that the shocks that I got seem to be too long for the car. The eBay listing specifically said that they were meant to fit an RC10 so I'm a little unnerved about that.
...

If the shocks aren't as described, you really should send them back.

[juicedcoupe]

May not be the exact same listing but a set like that was the first thing under "rc10 shocks", and this was also included.

[Dadio]

That's coming together nicely

[Oblivious1984]

May not be the exact same listing but a set like that was the first thing under "rc10 shocks", and this was also included.

Screenshot_20230425_142335_eBay.jpg

You sir have done more homework than I did. That's my failure.
To be honest I'm not really concerned. The shorter shocks are about the right length to act as rear shocks and I'm sure there's a set I can buy at the nearby store to fix the remainder of the problem.

I'll be 3D printing some more components tonight and hopefully tapping for tie-rods tomorrow. I've got a friend who's going to help me make the dogbones and axles from scratch in the machine shop, and then the last big thing to worry about will be the adapters for the truck transmission to work with dogbones. I'll keep everyone updated.

[Oblivious1984]

Edit: Accidentally posted the same thing twice - how does one delete a post?

[JosephS]

May not be the exact same listing but a set like that was the first thing under "rc10 shocks", and this was also included.

Screenshot_20230425_142335_eBay.jpg

You sir have done more homework than I did. That's my failure.
To be honest I'm not really concerned. The shorter shocks are about the right length to act as rear shocks and I'm sure there's a set I can buy at the nearby store to fix the remainder of the problem.

I'll be 3D printing some more components tonight and hopefully tapping for tie-rods tomorrow. I've got a friend who's going to help me make the dogbones and axles from scratch in the machine shop, and then the last big thing to worry about will be the adapters for the truck transmission to work with dogbones. I'll keep everyone updated.

You can use some spacers on the shock shafts on the internal of the shock to reduce the length. I run similar shocks on my rc10t2 and had to pull a lot of length out of them to make them work for a truck. Even the fronts shocks on the rear were long enough to pop the dogbones out of the socket

[juicedcoupe]

What length are the shocks, eye to eye?

Even original RC10 rear shocks were too long. You typically needed 5/8-3/4" of internal spacers for the correct length.



I suspect that the fronts are typical truck length, in which case you have another option.

Factory Works makes a front tower for using truck length fronts on a buggy.

Here are a couple of mine that use it.

[Oblivious1984]

You can use some spacers on the shock shafts on the internal of the shock to reduce the length.

What a great idea! I'll be taking the shocks apart this afternoon to design spacers.

What length are the shocks, eye to eye?

Even original RC10 rear shocks were too long. You typically needed 5/8-3/4" of internal spacers for the correct length.

Factory Works makes a front tower for using truck length fronts on a buggy.

Front shocks are 3.5 inches and rear are 4 inches. With the spacer thing I'll be able to solve the rear shock fitment perfectly but the front will need some additional adjustment to work. I think I might be able to 3d print an attachment that will work. If not, I'll purchase the front tower that you described.

Other updates - I'm continuing to 3D print and thread parts steadily. I also mocked up how I want to mount the transmission. I hate to drill through this chassis but I don't think it can really be avoided in order to properly mount this.

[Oblivious1984]

It's been a bit since I updated but I think you all deserve to see what progress has been made. Since my last post, I installed all of the tie rods on the front and back. That went pretty well! The front steering has a little bit more slop than I'd like, but that can be attributed to the imprecision of PLA parts on a low-quality printer.

I also mounted the transmission and got all of the hinge pins installed with C-clips. It crushed my soul to drill holes in this chassis, but at the end of the day it was the best way to mount the transmission and now it's on its way to being pretty secure. The electronics are mostly figured out and I'm happy with the steering range and throttle curve. I didn't end up using the speed controller that I wanted since it's too big, so I got a smaller one to do the job.

I took a stab at painting a body, something which I had never done before. I wanted to keep with the black/silver/gold theme, and I think it went pretty well for only using painter's tape and some generic acrylic paint from Michael's. Photos below - it stacks up pretty well against my dad's car! Now I've just got to make a sticker with "15" on it to match his and I'll be happy.

Next steps are to 3D print the shock spacers and some custom mounts to fit the battery. I'll update you tomorrow if that goes well!

[Oblivious1984]

Updates for everyone:
1) The 3D-printed spacers worked wonderfully for the shocks. There certainly is less travel than before but the car still has enough range in the suspension for me to be happy.

2) I've gotten a start on figuring out what to do for some traditionally metal parts on the car. The nose tubes were easy - I referenced my larger CAD model in order to make my own 3D-printable version:

3) The axles I decided needed to be much more precise, and so I've kept those as metal. Since I went with 3/16 wheels and bearings, the axles have been harder to source. Many people on eBay were asking ridiculous prices (one dude wanted $100 just for the rear axles ), so I grabbed some extra stock and machined my own axles with M4 threading on the end (I have nylock M4's on hand). It went pretty well for having not used a machine lathe in 6 years!

axle.png (442.6 KiB) Viewed 1221 times

axle.png (442.6 KiB) Viewed 1221 times

4) Electronics for the car are pretty much set now, and I'm happy with them. I made raised battery holders so that cables could be threaded underneath, but that had the side-effect of raising the battery up too high - it conflicted with the shell. I was able to get around that by trading the traditional plastic retainers with some extra-thick heatshrink. It's super secure now, so I'm not worried about it going flying in the event of a crash.

Next steps are to machine the rear axles and pins to get the rear wheels mounted up. I also need to trim the body still and get a better system than a paperclip for turning the car. Once those things are done, all I'll have left is to machine the transmission lockers and dogbones and then this thing will be good to hit the road!

[juicedcoupe]

Nose and wing tubes are easily made with K&S 83060 tubing.

JConcepts, JC Racing, and Dynotech all sell the aluminum front axles.

JC Racing makes rear universals in both (3/16 and 1/4) sizes and Custom Works has CVD's in 3/16.

[Oblivious1984]

Big update for everyone - she runs!!!

I ended up doing the same thing for the rear that I did for the front because it was pretty expensive to get things from the UK. That turned out to be blessing because then I was able to just order adjustable rear axles off of amazon and throw them in (photo of the finished rear setup below). I extended and 3D printed some wider arms to make all of this fit nicely.

The car looks beastly next to my dad's, I really couldn't be happier with the stance.

In terms of driving, it does handle very differently than the original RC10. Especially with no differential, I found that it wants to kind of launch itself on turns. I did buy additional gears to make the gear ratio identical on both sides. Even so, running this car at 100% throttle is scary. The thing can easily do a wheelie if I'm not careful, so I spent some time tuning it to accelerate more to my liking. What a blast!

I know that beauty is in the eye of the beholder and I'm super biased having built this car, but I think it really does look fantastic as a modern interpretation of the RC10. I was considering joining the running for build of the month next month... thoughts? Do you guys like the car in general or is it an abomination?

[Frankentruck]

This is a nicely done build! I personally prefer having a working diff but in a straight line on loose surfaces this is probably a rocket!