Chassis design help

[OTHGbronco82]

I want to make my own chassis for my MRC and I have a rough sketch right now. With the cab included it's right around 3.5 inches tall at the highest point and in between 6.75 and 7 inches long. Was just wondering if this chassis would be legal. I can probably take off a 1/4 of an inch from the cab and chassis and bring the total height down to 3 inches.

[Dravpnir]

Originally Posted by OTHGbronco82

I want to make my own chassis for my MRC and I have a rough sketch right now. With the cab included it's right around 3.5 inches tall at the highest point and in between 6.75 and 7 inches long. Was just wondering if this chassis would be legal. I can probably take off a 1/4 of an inch from the cab and chassis and bring the total height down to 3 inches.

Accordingly to the 2013 rules (cannot find any for 2014) the chassis has to be atleast 6.75" long, 2.5" wide and 2.75" high.

[OTHGbronco82]

I drew a box 6.75" long and 2.75" high and went from there. I'l probably end up making it just a hair longer and taller than the box just to make sure. Thanks for the input.

[MRCrackhead]

Keep your front and rear upper links level with the ground, at ride height.

Add holes above and below to adjust from there, but that's a good starting point in almost every case.

Forward bias rake on the skid is always nice.

Keep the lower links as long as possible.

Um, that's about all I know....lol.

Oh, and never fry bacon naked...... now that's really is everything I know.....lol.

[OTHGbronco82]

Originally Posted by MRCrackhead

Keep your front and rear upper links level with the ground, at ride height.

Add holes above and below to adjust from there, but that's a good starting point in almost every case.

Forward bias rake on the skid is always nice.

Keep the lower links as long as possible.

Um, that's about all I know....lol.

Oh, and never fry bacon naked...... now that's really is everything I know.....lol.

I have a chassis that I'll be borrowing the geo from. I'll probably modify the length of the skid plate though. If I can, I'll get enough G10 or Delrin to make 2 chassis and send one of them to one of the more experienced MRC guys to see what they think of it.

[MRCrackhead]

Originally Posted by OTHGbronco82

I have a chassis that I'll be borrowing the geo from. I'll probably modify the length of the skid plate though. If I can, I'll get enough G10 or Delrin to make 2 chassis and send one of them to one of the more experienced MRC guys to see what they think of it.

Oooooh, pick me, pick me!

Hahaha

[OTHGbronco82]

Originally Posted by MRCrackhead

Oooooh, pick me, pick me!

Hahaha

Maybe. If I can I'll try and get enough for 3 and send one to either you, winner, or everetty. Just depends on when I get some G10.

[OTHGbronco82]

So photobucket finally quit being a bitch and now I have pics. This is how far I've gotten. The box that it's in is 6.75" long and 2.75" high. So the chassis is just over the requirements for height and I'll probably make it a tad longer just to be safe. I might also redesign the cab later on but I kinda like it. Plus I think it'll be better when rolling over with the rounded cab. Might go with something that's close to a Chaotic Switch. And yes I realize it looks a lot like t3rry's design, but it's slightly different and is what I came up with.

[MRCrackhead]

Looks good.

I'm not happy with my current chassis because the upper link mount holes are all over the place.

To adjust up or down slightly, you also move fore and aft; otherwise you have to move really far up or down to stay in the same "hole" (if that makes sense).

They don't offer ease of adjustment like your vertical lines should.

[OTHGbronco82]

Originally Posted by MRCrackhead

Looks good.

I'm not happy with my current chassis because the upper link mount holes are all over the place.

To adjust up or down slightly, you also move fore and aft; otherwise you have to move really far up or down to stay in the same "hole" (if that makes sense).

They don't offer ease of adjustment like your vertical lines should.

Yeah, to many holes and it gets complicated trying to figure out which works best. Now I'm in the process of angling the skid plate and some other stuff. I need to figure out what I can sell so I can buy some G10 or maybe some Delrin. First chassis will be cut out of what ever is cheaper.

[FocusMiah]

That is looking good. I think i am going to do the same and use your idea of the box and see what i can come up with. Until i can get a Karnage chassis lol!

[OTHGbronco82]

I've had some feed back and this is what I came up with. Version 1 on top and #2 on the bottom.

[MRCrackhead]

I would keep the front shock mounts higher than the rear by the amount of "rake" you're trying to achieve.

The skid rake you show on #2 will happen naturally that way.

Tilting the transmission forward just causes clearance issues with the spur gear and the front of the chassis.

You'll have to make the chassis longer to allow the room needed for the tilted spur.

Longer chassis equals shorter upper links.

Simply "raking" the shock arms tilts the entire chassis instead.

That should give you what you're aiming for, without having to limit the front shocks as much internally.

You may need to limit them externally, if you ultimately end up with more articulation than you want; but that's much easier than internal limits (oil, bleeding, shock rebuild, etc.)

I always prefer to limit my suspension; not be limited by it.

For me, the rear shocks just never seem to be long enough, the fronts are often too long.

I've rebuilt many shock arms trying to compensate for what should have been in the design from the start.

Draw a straight line through the front and rear shock mounts, tilt until that line is level with the ground, and see what the skid looks like. Adjust from there.

#1 may be closer than you think.

Just my 0.02

[OTHGbronco82]

So something like this? From the red line moved up to the blue line.

[MRCrackhead]

Yup.

Now draw an imaginary line from approximately the center hole "blue line" front shock mount, to approximately the center hole rear shock mount.....hold the imaginary line level with the ground and see if the chassis rake is about what you want.

That gives you rake, with full piston travel on both front and rear shocks.

Articulation should be much more than you need, but limiting is a nice option to have.

[MRCrackhead]

Make sure the "blue line" is still 1" below the top of the cab to keep it legal.

If not, perhaps it's the rear that needs to be lower.

[OTHGbronco82]

I've got it figured out. And it was the rear that needs to be lower. I'm going to screw with it in Inventor and see if I can get something that looks good.