Race chassis?

[moparkid88]

im liking where this is going... what if you just bought a empty axial tranny housing and went off from there. its cheap and youll have it there if anything else comes up. i do remember now the txt tranny having the shafts more towards the center of the housing.. what about esc and rx locations?

 

[DeathWish]

You're right, the shaft's come from the center but the pumpkins aren't center on the axles. I could buy a empty trans later down the line once I get everything going. I'm thinking about putting a plate or something up front by the shock tower, I believe that would be best for it. Keep a lot of the weight up front.

 

[moparkid88]

so i take it you have a hook up on a cnc? im in school now for my toolmaker apprenticeship.. when i get some vacation time im going to take a cnc class.. are you going to have the support bars going from one side of the plate to the other?

 

[DeathWish]

A friend of mine that works at a AmTrac train yard does and he's been helping me with another project, CPE Evo Wheely King aka Race King. Yeah, I plan on adding cross braces, how many, that I don't know just right now. Have to get a prototype and go from there. What I might do is order some cross bars from Brett and go from there. Just have to wait and see how everything works out.

 

[moparkid88]

that would be a good idea.. then they would be the same width as his chassis...

 

[DeathWish]

I might cut them down some so they aren't the same as the Ground Pounder and a little easier to put the Wheely King trans in without having to put of spacers in there.

 

[william g]

what if you mounted the trans backwards, motor sticking towards the front and the battery crossways in the chassis right in front of the spur/pinion?

That would keep the battery weight lower and near the truck's f/r center

 

[jetboat]

I hate to give out my ideas but...

Mount the trans in the stock config, then have a motor mount that puts the motor in front and below the gear. Ive built a couple crawlers like it and it works perfect.

With 2s lipo the weight savings by dropping the battery below the trans is marginal but its there. Most racers also wont be running a 4000-5000mah pack for a race, they will run a 1000mah and they weigh next to nothing. However, if I ever get around to redoing mine I will put a lower mount. Currently I run my battery crossways above the motor (axial trans) and it works great.

Dont design it around the stock wk shocks. They suck and there are no good options in that length. Design it around some xxl (4") e-maxx shocks (or at least give the mounting for them). Sure you loose some travel but they are 1000x better shock.

 

[DeathWish]

I'm not really designing it around anything on the Wheely King, just designing it off real monster truck chassis'. I'm thinking about possibly making the chassis' about 15.5-17 inches long. Yes, It seems kinda of long and added weight but that's what prototypes and testing are for.

 

[jetboat]

my 13-14" chassis came out to be 16" long. My 12-13" chassis is about 14" long. Just to give you some ideas.

 

[DeathWish]

Thanks, any and all ideas are welcome as I try to get something worked out with my friends.

 

[DeathWish]

Alright, a small update about the chassis'. After sitting down and talking with my buddy, we kind of thought of a way to do the chassis' to keep them light, durable and still look nice to everyone. The thought is to use some aluminum that's a little thinner than .125 and closer to that of the Ground Pounder. With what we have going in the thought process is to have the chassis outlining the real chassis BUT to only cut out small parts of the chassis on the side around the cradle and where the transmission would go. All of this will change with each chassis. Thoughts on this?

 

[bpare207]

Then this won't be a race chassis. It'll be a scale/replica MT chassis made of aluminum plate.

 

[DeathWish]

I don't see how it wouldn't be a type of race chassis when it'll be kind of like the ones CPE makes for the Clod Buster.

 

[DeathWish]

William, that's a good idea. Or another thing I could try is moving the motor and trans more toward the front of the chassis and having the battery in front of the spur/pinon still.

 

[william g]

problem is if you move to far forward the front driveshaft gets very short and the rear very long.
That's why if you spin the trans around putting motor weight forward and battery rearward of transmission near the spur running side-side it'll center the weight pretty good.

I've setup one of my GP-WK's with 75mm long front links 85 rear and the front shaft compared to the rear shaft is a lot shorter for just 10mm of centering difference.

 

[DeathWish]

True, I guess I can incorporate 2 sets of mounting holes so you can run the motor in the stock position and reversed with the motor up front. This weekend I'm going to sit down and draw up some chassis ideas and hope to post some pictures of them on Monday or Tuesday.

 

[jetboat]

might I suggest a different material... Aluminum bends on a hard impact and doesnt bend back well, I would use either g10 or delrin. Either of those will also cut weight without sacrificing strength.

 

[JKRacing37]

I don't see how it wouldn't be a type of race chassis when it'll be kind of like the ones CPE makes for the Clod Buster.

If you look at clod race chassis they all have the batteries mounted at the lowest possible position, and also the electronics tray is as low as they can get it and not interfere with the movement of the links. There is not any extra material that extends forward and rearward past what is needed for shock mounting locations. Obviously this does not give a scale appearance as there is no truck 1:1 truck that runs shocks on the links and has no frame at the front or rear of the truck, but what is does is lowers COG by not having any unnecessary material up high and centralizes mass fore and aft. Look at the CPE Terminator chassis as an example of what I'm describing:

Terminator Chassis

I think that is why people would say this is not a "race specific" chassis. Most of the chassis that are marketed as race chassis you would not want to bash with.

Also, to avoid tire/lower link interference (especially if running Clod sized tires) don't make the chassis too wide. This will help taper the lower link away from the front tire as the tires turn left and right and help avoid rubbing.

I can't wait to see what you come up with though. Sounds very interesting. Are you going to do any CAD drawings or anything like that or just jump right into prototyping?

 

[DeathWish]

I understand what you mean by the clod chassis but the difference is that a clod has the motors on the axles and a WK doesn't so everything kind of centers around the transmission and motor. Maybe that's what some aren't seeing I'm not sure. I'm going to try and keep it about the same width as much as possible. This will be more like a real monster truck than anything dealing with the weight placement. As for drawings, I'm going to just draw up a few designs on paper and then go from there. I hope to have something to show this coming week as for a design. I might just do a simple design first and see how it goes.