The Nanotube

[microgoat]

Thanks to Grover and Azvader for the inspiration I decided to re-do the TLT yet again, lower and lighter. This time there's nothing but a carbon-fiber backbone connecting the upper links. Wasn't that hard, as the old Microgoat chassis' shock and upper links shared mounting points, at least up front. Re-doing the rear to match was no biggie.

The backbone is constructed of a 1/2 inch CF strip, with .210 CF tubes joined to the ends. They're glued on with CA, layered with CF tape and epoxied, cross-wrapped with another couple plies of CF tape and epoxied again.

Yes, I know it's a globby, ugly mess. A little sanding will clean it up some, if it survives the initial testing. If it doesn't, then I won't bother. The backbone is pretty flexible, but the joints themselves are quite rigid.

The motor is facing backwards because it's an outrunner, and they don't care which way they spin. This way the gear cover acts as a skidplate.

I still need to add driveshafts and bolt on the upper links. Still in the mockup stage now, but it looks promising.

The chassis (such as it is) weighs about an ounce and a half.

[Double J]

Thats ugly but cool.
Let us know how it tests.

[Highmark]

I dig it


If it doesn't survive, you may want to consider building it out of a solid piece of carbon. I doubt the joints on that one will break but using a more uniform piece will make it less likely to break.

[microgoat]

The area I'm most worried about is the center, where the two holes are drilled. The holes themselves are CA'd, epoxied and have aluminum washers for reinforcement, but that's still the weakest part of the chassis.

I'm considering joining the upper link mounts to the lower link mounts as well, to cut down on chassis flex. At this point, the extra weight isn't going to be a problem, and I've got plenty of CF tube left over.

[dezfan]

It's butt ugly, but if it works, this will be the bomb!!!! And I thought the RD XL4 chassis at just under 4 ozs. (3.8 oz.) was light! Keep us updated Goat! Damn, now I have to shave some more weight of the Grunt!

[azvader]

Originally Posted by microgoat

I don't know, the more I think about it, the more I think I have to Xerox this one.

But that aluminum is soooo 20 minutes ago Mine's gonna be carbon fiber

And don't ask, it'll be a one-off booty-fab, not for resale.

I like your twist on the Rover design. I think I hitting the LHS for one of those tranmission skid plate tomarrow.

I know aluminum isn't cool but it's what I had. I gave Grover an old carbon fiber handle bar, I wonder what he's doing with it.

[microgoat]

If this works even a little bit, I'll re-do it with woven CF instead of the CF tape. Should be a lot stronger and much better looking. Probably lighter, too, since laying my own plies isn't the most effective method (LHS only had Dave Brown CF tape).

While the CA'd plies went on fairly smooth, the epoxied plies got bumpy and nasty, as the pics show. Doubling up the main spar wouldn't hurt, either. Overall, I think there's a ton of potential here. I should have it running tonight.

It's still 72 ounces without driveshafts or body, but with electronics and battery pack. What I took off by using CF instead of aluminum, I put back by using a full tranny case and gear cover, but the weight is much lower. The highest point on the chassis is 3/4 inch above the top of the tires

[Wrecker]

That's awesome! I can't wait to see it finished up and see how it performs.

[grover]

Originally Posted by microgoat

What I took off by using CF instead of aluminum, I put back by using a full tranny case and gear cover, but the weight is much lower. The highest point on the chassis is 3/4 inch above the top of the tires

Microgoat, I love it!

Hope it is strong enough/works out for you.
Why not hack the extra plastic off that tranny?


Mike I will look in the garage for that carbon bar if you want it LMK.

[microgoat]

Thanks Grover. I left the extra plastic on the tranny to protect the outrunner. Since the can spins, it needs a little protection from rocks, twigs and all the junk we encounter out there. I've got a few ideas to beef it up if I have to.

[mike]

How well does the suspension work with the upper links mounted on the shock mounts?

[microgoat]

I can get 7" under a wheel before another wheel comes off the ground, using Jato shocks. That might change a little once driveshafts go in and start binding.

12-1/2" WB
2-1/2" center clearance.

[Rockpiledriver]

That's very cool. A piece of flat alum plate say 1/4" would probably get the job done too. It might not be a whole lot heavier. Gret idea!

[dezfan]

Just ordered a CF plate off e-bay. I think I'm going to play too!

[JohnRobHolmes]

Wow. That is pretty cool! Of course I am partial to anything with laminate layers.

I can see that the middle part would be the only weak part really. A hard fall might shatter it. Only one way to find out!

[microgoat]

Here's a shot from the side. I'm planning to use this RPM Maxx skidplate (mounted sideways) for now to protect the bottom of the tranny. It's a good fit, just needs a few more holes.

Other than that and charging the battery it's ready for the rock test. I still need to move my indoor rockpile back outside.

I can already see where the chassis is going to fail. The epoxy is starting to pull away near the center, where the vertical tubes (tranny spacers) attach to the center spine. Version 2.0 will address that if it lives up to its potential.

Also note the mandatory flex shot

[dezfan]

Originally Posted by microgoat

Here's a shot from the side. I'm planning to use this RPM Maxx skidplate (mounted sideways) for now to protect the bottom of the tranny. It's a good fit, just needs a few more holes.

Other than that and charging the battery it's ready for the rock test. I still need to move my indoor rockpile back outside.

I can already see where the chassis is going to fail. The epoxy is starting to pull away near the center, where the vertical tubes (tranny spacers) attach to the center spine. Version 2.0 will address that if it lives up to its potential.

Also note the mandatory flex shot

Looking good Goat, looks pretty "flexy". Lets hope v1.0 holds up so we can see v2.0. I ordered some CF plate and some Delrin Stock. Going to do a Stealth based chassis. Can't wait for the crawling pics!

[JohnRobHolmes]

Steath chassis with lightweight outrunner ??

That would be even nicer! How about a "tuber" made from CF tube and rod? I have all kinds of that sitting around, and just bought 700+ feet of CF tow for $8 shipped. That would be enough to do a "tuber"

[EeePee]

Originally Posted by johnrobholmes

A hard fall might shatter it. Only one way to find out!

Cough cough. I know of a particular place where he has experience with some saaaaaaaaahweet driving moves.

[dezfan]

Originally Posted by johnrobholmes

Steath chassis with lightweight outrunner ??

That would be even nicer! How about a "tuber" made from CF tube and rod? I have all kinds of that sitting around, and just bought 700+ feet of CF tow for $8 shipped. That would be enough to do a "tuber"

Now if I could only find a "CHEAP" source for an outrunner???? Hmmm???? What to do?