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Old 02-04-2007, 12:47 PM   #31
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The Revo's chassis is very complex so therefore it will break less than a flat CF chassis.
Redman-tell me why buggies put out more power than Revo's, please.
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Old 02-04-2007, 01:18 PM   #32
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How often do you see a nitro car running to cool even with the chassis helping to dissipate the heat? Not very often.
If you're talking five minute runs then it wouldn't make much difference, in which case you might as well race electric.

Buggies and truggies use bigger engines thus putting out more power. Unless you're talking about guys who use a different kit to mount a bigger engine in a revo in which case they would be equal power if you used equal engines.
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Old 02-04-2007, 07:02 PM   #33
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I will say it again, heat will not be an issue with a carbon fiber chassis. Myself as well as countless others have used a cf main chassis with the lst truck. Running a xtm 457 .28 in a large monster truck had no ill effects on the chassis. I later parted out the truck and there were absolutely no marks where the engine had been mounted.

There is a big difference between a cf chassis on a revo/lst vs a 1/8 buggy. On a MT the chassis is not as exposed and does not take the abuse that a buggy would take. Look at the underside of a well used buggy and you will see the abuse that it takes. The wheels are not large enough to prevent bottoming out or casing the chassis on bumps and large jumps.
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Old 02-05-2007, 11:28 AM   #34
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I want to say thank you for all the comments so far on this topic.

Is there any factory guys in this forum with comments on this topic?

We are in the planning stages of this project, and the first ones will be towards the 8ight. The process we are working on will produce a chassis with all the features of an aluminum one molded in. Meaning the flywheel cutout, molded edges etc. etc. This will not be a chassis cut from flat stock like the 1/10th cars.

Thanks again and look forward to more comments.
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Old 02-05-2007, 11:48 AM   #35
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open the flywheel hole up a bit more to fit the chrome tops without filing

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Old 02-05-2007, 12:28 PM   #36
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If you open the starter box hole anymore, you invite rocks and pebbles. It's much easier to narrow the wheel if your starter box to fit. Just spin the starter box and hold a file against the wheel. Done!

As has been beaten to death over and over, nitro cars use the aluminum chassis as a heat sink. The chassis doesn't generally get too hot because the heat is dispersed over the length of the chassis. I don't think a carbon fiber chassis will necessarily make the engines run too hot, but it's something to think about.

As for weight savings, you'd be removing weight from the absolute lowest and most central point of the car: the chassis. That instantly raises the CG of the car. Not necessarily bad, but not always good.

Designing the chassis to flex like the stock chassis would take some work. Aluminum may not necessarily be used as chassis material because of its flex, but it certainly doesn't hurt. As was said, flex is a very important aspect of all R/C cars and allows them to be easy to drive. Stiff cars don't work, period.

Molding the side guards into the chassis wouldn't be the best idea in my opinion. The five screws (or whatever it is) is hardly any weight savings (and again, that weight is very low to the car). If you take a hard side-impact that would crack the side pod, now the whole chassis is wasted, because you can't just replace the side pod.

As well, I can't believe durability won't be an issue. I'm sure the carbon fiber materials that the F1 guys use are a little too expensive for this application, haha. I've personally obliterated 4mm carbon fiber shock towers in 1/8th scale, in a racing environment. I would guess that a good chunk of your customers will be non-racers, and they beat their cars up WAY more than racers do on the track.

Many touring car CF plate chassis need to be sealed at the edges by the consumer. The whole drill....dab glue on the edges of the chassis, file it round, etc. If your chassis needs that to be done, I'm sure most racers/hobbyists won't take the time to do it correctly and you'll have chassis splitting everywhere.

I'm still not convinced that you'll be able to produce a carbon fiber chassis that performs as well as the stock one, holds up to the abuse of the people that are going to buy it, and still make money. I can imagine that the profit margin of producing CF parts scares companies away from it for certain projects. If you can, then heck, more power to ya!
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Old 02-05-2007, 01:51 PM   #37
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if you can mold front kick-up into it that weould be good..

Hit one rock with the chassis and scrapes will show...
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Old 02-05-2007, 01:54 PM   #38
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The chassis on my car is worn to the point where the rear screws will need to be slotted to get them out. I don't know how well CF will hold up to that?
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Old 02-05-2007, 03:52 PM   #39
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As a Carbon Fibre Technician, This is quite an interesting thread. I do not see heat being any sort of problem. As I work for a company supplying parts for Toyota F1 our carbon fibre will have to withstant huge temperatures. Although some types of carbon fibre with be able to tolerate the temperatures better than others. The scratching on an 1/8th car is something that you just will not get away with. Just look at the bottom of any electric touring car. Covered in scratches. Though it is a great idea. Will make the car very stiff and with not bend under impact as easily as aluminium.

Just don't try an use F1 grade carbon. Will cost in the region of about $1000.

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Old 02-05-2007, 04:16 PM   #40
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I sure heat is not a factor in that the carbon fiber would not be damaged but it would have an effect on motor cooling. As far a delamination, I know it would be a problem. The cost is probably the bottom line, compairing the carbon fiber fabrication technics of F1 to what we would get in a $600 buggy is not realistic. Has anyone seen the budgets F1 teams have? I don't see Losi or Kyosho (or anyone else) investing in autoclaves & all the other stuff they would need to do it right.
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Old 02-06-2007, 09:33 AM   #41
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I really appeciate all the input that is coming in on this topic. Thank you all.

Starting with the chassis stiffness, we can alter the layup schedule to change the characteristics of how the chassis flex's and distributes the load through out the entire chassis. Thats the beauty of it, being able to try different layups such as do you want more front to rear rigidity or more torsional rigidity. I also think that shock technology has gotten a lot better, thus being able to tune the car around a stiffer overall chassis setup.

The scuffing issues are what they are, they happen with the aluminum ones and they will happen with the carbon ones. Maybe there is a vac formed lexan underbody, or even better how about molded recess's to accept alu., titanium, or carbon replacements in the rear and front of the chassis. These are all doable.

Aaron I agree with you about molding in the sidepods, that would be a mistake. As far as the sealing of the edges that you talk about that is one of our top priorotites, this chassis will have no cut edge's like a chassis made from flat stock. It will be 100% molded, edge's, flywheel cutout, even the countersinks for the screws, etc. etc.

Thanks again for all the input.
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Old 02-10-2007, 12:46 PM   #42
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Hey Aaron I just noticed that you are located in Escondido. If I build a chassis would you be interested in trying it? My shop is in San Marcos, and we are moving forward with this project.

I look forward to hearing from you, either way.
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Old 02-11-2007, 07:06 AM   #43
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If you have the ability to lay up the carbon to facilitate flex then I think this is a WAY good thing !! You HAVE to have chassis flex !! You can't tune reactive camber in with shocks ! This is what you get with chassis flex. Also if the carbon flexes a bit more you can tune it with your chassis braces smaller part, easy to make = big tuning devise for little $$
I will say though you need to cool the engines ,especially the lower end ! How can you do this with carbon ?
Also transponders DON'T LIKE CARBON ! They have a hard time getting the signal through ? I have noticed this being a track owner and watching the Jammin's not count because of the holder they use ??
I really like the idea of changeable inserts for wear ,heck even the aluminium ones could use these .
2 things of most importance ,flex and heat dissipation all the rest can be fixed fairly easily.
Do you have FEA ? If so compaire the 8eight chassis flex to your proto-type carbon unit and see what you get ?
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Old 02-11-2007, 12:26 PM   #44
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being old school back when the rc 10 came out people were trying carbon fiber chassis and fiberglass resin chassis the wear factor and flex on the smaller electrics just weren't worth the extra work and expense of making them by hand.also along the same lines if you have any questions take a look at the k-factory chassis for the 777 sp2,it's a blend of carbon fiber and alum.the flex is there and the chassis works very well in rough track the carbon fiber is used mainly to stiffenen up some of the flex from the alum chassis.this might be the way to go just my 2 cents worth lol.of course i run kyosho 777 sp2 and k factory parts i might be biased but oh well lol
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Old 02-11-2007, 04:41 PM   #45
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Ya know, I checked the chassis temperature of a few 8IGHT buggies last night while thinking about this thread. I didn't break out the temp gun or anything, but I just touched them with my hand to see what was going on.

I don't think this thread has given enough credit to the heat sink capabilities of an aluminum chassis. Some of the cars I touched last night were pretty darn hot. Not hot enough to burn and certainly not hot enough to cause warping or any other problems with carbon fiber, but still hot enough to where the lack of cooling from the chassis might create an issue.

Matrix - San Diego County rocks, doesn't it?

I really appreciate the offer, and I'd love the opportunity to help R&D a project like that, but I'm obligated to run Losi OEM components, especially big stuff like chassis and drivetrain. I know Kyosho's race team has gone to that approach and I think you'll see that trend continue among all the race teams.
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