More Range of Suspension Movement w/These Parts?

[DLuders]

Can you use Bionicle parts (with BALLS on the ends) to click onto Technic Connectors (with Ball SOCKETS) to make BIG Suspension Steering Arm units? My son and I want to make a big Technic MONSTER TRUCK with a big, beefy suspension having GREAT RANGE of movement. However, the selection of Technic Suspension pieces is rather limiting for larger vehicles ( http://www.bricklink.com/catalogList.asp?c...P&catID=141 ) . The official Lego suspension arms offer too little vertical travel for a Monster Truck.

So, I ordered a few items from Bricklink, got them in my hands today and fiddled with them. It is possible to make a jumbo Suspension Arm assembly that's a LOT BIGGER than the ones you're used to. As pictured below, the three key pieces are the #47330 "Bionicle Vahki Torso Lower Section ( http://www.bricklink.com/catalogItem.asp?P=47330 ), the #60176 "Technic, Axle Connector 2 x 3 with Ball Socket, Closed Sides, Squared Ends" ( http://www.bricklink.com/catalogItem.asp?P=60176 ), and the #bb78 "Technic Ball Joint with Double Rack" ( http://www.bricklink.com/catalogItem.asp?P=bb78 ), which Peeron lists as Part #x843.

My digital camera is on the fritz, so I'll try to describe the steps below:

1) Snap the balls of 1 ea. #47330 Bionicle Torso onto 2 ea. #60176 Connectors with Ball Socket, to form the top and bottom pivots of the Steering Arm. The #60176 Connector with Ball Socket pieces (in turn) pin onto LONG Technic Liftarms of your choice using blue #43093 "Technic, Axle Pin with Friction Ridges Lengthwise" ( http://www.bricklink.com/catalogItem.asp?P=43093 ). Alternatively, each #60176 Connector with Ball Socket piece can connect to 2 ea. Technic Liftarms directly, using 4L Technic Axles. NOTE: Don't use the lookalike #32174 "Technic, Axle Connector 2 x 3 with Ball Socket, OPEN SIDES" pieces; they are weaker than #60176 and crack easily (see http://www.bricklink.com/catalogList.asp?q...ith+Ball+Socket ).

2) Note that the #47330 Bionicle Torso piece has a choice of two central holes through which an axle can connect onto the wheel. Axle-to-wheel connections can be made stronger by using 2 ea. #4185 "Technic Wedge Belt Wheel (Pulley)" ( http://www.bricklink.com/catalogItem.asp?P=4185 ) on the outside of the Steering Arm assembly (next to the wheel). They allow Technic pins to snap onto the wheel's outermost holes to reduce the torque on the axles.

3) Connect 1 ea. #bb78 Ball Joint with Double Rack to the #47330 Bionicle Torso using a 3L Technic Axle. Then, snap 1 ea. #60176 Connector with Ball Socket onto the ball of the #bb78 Ball Joint with Double Rack, to offer a pivoting connection to your steering rack assembly. The back-and-forth rotation of the #bb78 Ball Joint with Double Rack causes the #47330 Bionicle Torso to pivot (thus steering the wheels). There is a WIDE-RANGING 3-directional SWIVELING action -- up, down, and back-and-forth. The combination of Ball-and-Socket connections are a bit snug, so if one wanted a looser fit a bit of sandpaper on the balls could reduce friction a tad.

Hey you experienced "Trial Truck" builders out there -- do you think that this concept is worth developing further? Maybe somebody else has already thought of this, but I don't think so. Feel free to experiment and comment, and use it in your own MOCs.

[backbone]

It`s bad idea in my opinion.

Ive tried this concept, practice proved that is too tight link for suspension.

And ball socket and ball parts are good, but hard to make good and durable suspension for trtr.

[DLuders]

It`s bad idea in my opinion.

Ive tried this concept, practice proved that is too tight link for suspension.

And ball socket and ball parts are good, but hard to make good and durable suspension for trtr.

OK, but if you SLIGHTLY SANDED the balls, wouldn't it be a looser fit? The parts are MUCH MORE ROBUST than the standard Technic Suspension pieces.

[backbone]

Without any modifications of socket or ball parts, this suspension idea is not quite good.

Build, and test it - and another problem - size of suspension built with these parts.

I think it will be hard or impossible to build it in 1:13 scale or smaller.

Edited March 27, 2010 by backbone

[Ras_Al_Ghul]

I haven't done much work with them personally, but they are so tight fitting that I imagine they can only work in VERY large scale models. The only ones I've ever seen are some of nicjasno's cars.

[DLuders]

Thanks for the feedback. I'm not trying to make a 1:13 scale official "Trial Truck" conforming to the official BrickTruckTrial.com rules. My son and I want to make a big MONSTER TRUCK (which has an oversized suspension and wheels).

[Blakbird]

Thanks for the feedback. I'm not trying to make a 1:13 scale official "Trial Truck" conforming to the official BrickTruckTrial.com rules. My son and I want to make a big MONSTER TRUCK (which has an oversized suspension and wheels).

I think you are between a rock and a hard place with these ball joint parts. In stock configuration, they are so tight that your suspension won't be able to move under it's own weight. If you sand them down (which is kind of cheating) they will rotate more easily but they will also pop out of the socket more easily making them fall apart if you bump them too hard. I think you need parts with positive locking.

By the way, there is no particular reason you need purpose built suspension parts at all. Just build them up out of beams like the old Technic sets. Then you can make it as big as you like.

By changing the position and mechanical advantage of the shocks, you can get plenty of travel like this MOC from Grazi. If there is not enough spring force, you can always put a few in parallel.

[Front]

One thing that is possible it to place the Bionicle sized balls between two Technic beams, so that the ball fits in between two Technic holes. It will give a ball-link with more or less zero friction. But off course the movements will be limited somewhat by the cross axle colliding with the two beams. But still is allows some 3D movements.

[Zerobricks]

Too bulky, too much friction... And beside TT's usually use solid axels, not independent suspension. Only good for nicjasno's cars, but they were sanded and the car uses some heavy non lego mods.