Hello fellow technic aficionados, my name is Technicbuff and I am a lurker on these forums. Today I present you some questions which form the basis for my first topic here.

I hope you may be able to help me with a couple of questions regarding technic pieces. Most of these are regarding parts which I currently do not have.

1) Can the wheels from the 8880 set be mounted on regular axles? I.e. Is it is possible to construct a viable suspension design that does not use the specialized hub pieces? (bricklink part #s 2999 + 2097 + 2738)

I do know that in an official technic set (8857) those exact wheels were mounted on a drive-train used to power a fake engine. The wheels were only secured with bushings: http://www.peeron.com/scans/8857-1/28. But I presume this technique would probably work using the friction force of the bushings only. I think the axle would slip inside the wheel if it was powered by a strong motor. That model had no suspension either.

I am planning a MOC that would use these wheels. I don't want to purchase the entire 8880 set because the old suspension parts are bulky, redundant, and I want to save money. This MOC would also use a pneumatic engine (LPE - derived) so the torque involved would be considerable.

2) Can the axle-hole in the old technic pole reverser (bricklink part # 6551c01) be driven complete around, or is there is a limited range of motion? I was thinking about how to make flashing sirens for a police car, and a mechanism could easily be built to achieve the rapid flashing effect.

3) Why are there no belts used in the drivetrains of any technic creations/supercars? I have viewed many different creations and I have never seen any model that uses belts in the drive train.

I remember building robots using the RIS 1.5 kit and I would use belts often as they provided flexible connection solutions and built-in torque protection. I would think even for steering racks that belts would be superior to normal gears if you didn't have a clutch gear available.

I understand there are some lengthy questions here, but I did not want to flood the board with several topics, so I have consolidated all my questions in this thread. I will patiently wait for your replies and advice. I have just emerged from a 6 year dark age and playing with Lego technic again is so reinvigorating.

Cheers,

The Technicbuff

Edited May 15, 201212 yr by TheTechnicBuff

1) Can the wheels from the 8880 set be mounted on regular axles? I.e. Is it is possible to construct a viable suspension design that does not use the specialized hub pieces? (bricklink part #s 2999 + 2097 + 2738)

I do know that in an official technic set (8857) those exact wheels were mounted on a drive-train used to power a fake engine. The wheels were only secured with bushings: http://www.peeron.com/scans/8857-1/28. But I presume this technique would probably work using the friction force of the bushings only. I think the axle would slip inside the wheel if it was powered by a strong motor.

Yes they can be mounted on regular axles. And there is more than a friction force to prevent slipping. It's hard to explain (with my poor english), but if you look at this picture from Technicopedia (http://technicopedia.com/8857/8857wheels1.JPG), you can see how the other end of bushing matches the wheel.

2) Can the axle-hole in the old technic pole reverser (bricklink part # 6551c01) be driven complete around, or is there is a limited range of motion?

Yes, it can be driven around, range is not limited in any way.

Edited May 15, 201212 yr by Meisseli

Lego uses rubber rings or chains instead of belts. I guess belts would be too special for general problems, because their length is fixed. By that I mean belts are used for solving common problems, and too many variations in length would be needed. Chains are expandable, so it's a flexible solution, rubber bands are elastic, and used in more special cases anyway.

And both of them are compatible with the other Lego pieces (like gears, wheels, bushings) while belts would require special wheels.

That's my guess

1) Can the wheels from the 8880 set be mounted on regular axles? I.e. Is it is possible to construct a viable suspension design that does not use the specialized hub pieces? (bricklink part #s 2999 + 2097 + 2738)

Yes. The bushing forms a mechanical lock with the wheel hub so it cannot slip.

http://technicopedia...8857wheels1.JPG

2) Can the axle-hole in the old technic pole reverser (bricklink part # 6551c01) be driven complete around, or is there is a limited range of motion? I was thinking about how to make flashing sirens for a police car, and a mechanism could easily be built to achieve the rapid flashing effect.

Yes. The pole reverser center can rotate all the way around, although no official set ever used it this way. These old pole reversers are very expensive, though, and I would guess that the contacts would wear out pretty quickly if you used them this way.

3) Why are there no belts used in the drivetrains of any technic creations/supercars? I have viewed many different creations and I have never seen any model that uses belts in the drive train.

A large number of older sets used belts in the drivetrain including 8480, 8485, and 8082. The only reason you haven't seen one in a supercar is because they haven't been motorized! The belts were used primarily as a clutch to protect the motor from stalling. Once the clutch gear was introduced with set 8479, they were no longer necessary so have become pretty rare.

You could combine 2x 3L thin beams, mount them in the holes of the rim, having the center be the axle tgat goes through them both. And you can use the pins for friction. I don't like to use rubber belts, because they slip, or they pull on the axle locations, if too tight, bending the axles and causing friction.