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thestug
2011.08.10, 09:48 AM
I have read somewhere that people heat their AWD chassis to help prevent the chassis from warping over time due to chassis heat. How is this done?

JAC
2011.08.10, 10:39 AM
Don't know about warping ,but one of my AWD staid on top of a mini oven broiler and over the course of several weeks observing how beautifull it looked I did'nt realize that the heat was transferring to the bottom of the car every time my wife used the oven. I noticed something wrong when the batterry door was hard to dissengage. Some of the plastic very mildly deformed(very hard to notice), what I did notice was many crack lines had developed thoughout the botoom-around the screws. The car was drivable and balanced. My point being, I'm not to confident about this plastics properties. Hope this helps.

thestug
2011.08.11, 12:36 PM
Interesting, I heard that heating a chassis will help prevent warping. Kind of like when metal is preheated before welding with a torch, but perhaps plastic won't react the same way.

JAC
2011.08.11, 03:54 PM
Interesting, I heard that heating a chassis will help prevent warping. Kind of like when metal is preheated before welding with a torch, but perhaps plastic won't react the same way.

To me the plastic cracking happens when it cools although i'm no expert.

Digitalis West
2011.08.11, 07:57 PM
This is not something I would do. When the plastic is molded there are stresses frozen into the plastic from the molding process. Some of this is from the forcing the thick melted plastic through the mold, some of it is from the uneven cooling of thick and thin sections of the part, some of it is from ejecting the part from the mold too quickly so that more parts can be made in the same amount of time.

If you warm the plastic up to a point where it is just about to flow, those stresses will relieve themselves causing the part to warp into a more relaxed state. I guess, in a sense, the car will not warp any more after heating it up... but this is not because heating up the part prevents warp, it is because heating it up will let all of the warp that was going to occur happen all at once.

The same is true for metal. This is why you heat it up before you weld and not after.

thestug
2011.08.11, 11:03 PM
This is not something I would do. When the plastic is molded there are stresses frozen into the plastic from the molding process. Some of this is from the forcing the thick melted plastic through the mold, some of it is from the uneven cooling of thick and thin sections of the part, some of it is from ejecting the part from the mold too quickly so that more parts can be made in the same amount of time.

If you warm the plastic up to a point where it is just about to flow, those stresses will relieve themselves causing the part to warp into a more relaxed state. I guess, in a sense, the car will not warp any more after heating it up... but this is not because heating up the part prevents warp, it is because heating it up will let all of the warp that was going to occur happen all at once.

The same is true for metal. This is why you heat it up before you weld and not after.

So the best idea is just to keep the plastic around the motor as cool as possible with heat sinks and such,right?

bermbuster
2011.08.11, 11:22 PM
So the best idea is just to keep the plastic around the motor as cool as possible with heat sinks and such,right?

sounds good to me....:cool:

Digitalis West
2011.08.12, 12:32 AM
So the best idea is just to keep the plastic around the motor as cool as possible with heat sinks and such,right?

This will help a lot. Being careful about where you store or leave the car is also important. ie. Leaving it in your vehicle in the parking lot while you are at work is a bad idea.... ask me how I know...:mad:

You can also try bracing the chassis with something stiff that will resist the warp. Carbon or glass fiber are good candidates. Something similar to the Kyosho brace for the MR-03 would work well.

thestug
2011.08.12, 12:41 PM
This will help a lot. Being careful about where you store or leave the car is also important. ie. Leaving it in your vehicle in the parking lot while you are at work is a bad idea.... ask me how I know...:mad:

You can also try bracing the chassis with something stiff that will resist the warp. Carbon or glass fiber are good candidates. Something similar to the Kyosho brace for the MR-03 would work well.

What kind of brace? I guess I have never seen a MR-03 with a brace. I guess i'm not really sure what this would look like on an AWD. I understand what you mean about leaving your car on someplace hot. I broke my very first chassis this way. Perhaps I should store it in the fridge. :)

Digitalis West
2011.08.13, 05:31 PM
You would want a thin carbon plate that connects the front and rear of the chassis. The carbon can be very thin because you are not trying to keep the carbon from bending but rather, you are trying to prevent stretch from corner to corner of the chassis.

Nominally you could just glue a really thin carbon sheet to the bottom of the chassis but on the MA-010, the motor access makes this problematic.

The other option is a bolt on carbon triangle for the top of the chassis. It could connect the antenna boss on the battery side to the electronics cover and rear suspension screws on the motor side.