Didumos69

Your standards remain high. Very impressive!

Straining the minor edge half way the 2L peg of a 3L pin is not the same as straining the outer edges of a peg or half peg as described in the referred amendments. But never mind, next time I think the Earth is round, I'll keep it for myself;-)

I will try with two half bushes and a belt wheel. If that will prove sufficient I will use that, What do you mean with 'illegal'?

I tried with two belt wheels, which are also a tight fit and these still slider off after pushing the suspension a few times. I think the nice thing about using the squeezed rubber connectors is that it actually 'damps' the side movement of the rim and recovers from this movement.

Hi, For the AWD platform that I'm working on (project 'Steppenwolf') I've been looking for a way to better fix the rims to the axles (5.5l with end stop) coming out of my self-composed wheel hubs. I ended up shoving a rubber connector (damper) onto the axle and squeeze it between two 2l lift arms. The short lift arms are attached to three 3l pins that are inserted into the rim and held in place with three more 1.5l pins and a belt wheel covering the hole thing. See image. The image has been rendered, but I applied this in real life and it actyally works, even in a setup with high suspension demands such as my AWD platform. The idea may of course also be applied to the similar rims with 6 pin holes. I thought this might be useful for others and may even look good on truck-like vehicles. The whole thing may of course also be placed on the inside of the wheel, but in a steering setup that would move the center line of the wheel away from the virtual kingpin, which I personally don't like. Regards, Diederik

Thanks! I will try this method. Regards, Diederik

Hi, I'm looking for a way to disassemble a large shock absorber, without causing any damage. I want to place a soft spring on a yellow/black shock absorber, which is originally equiped with a hard spring. Has anybody experience with this? Any help is very much appreciated. Regards, Diederik

For more info see this follow-up topic: http://www.eurobricks.com/forum/index.php?showtopic=123304

Update: I removed the images, the front suspension wasn't properly designed at this stage.

Having a full-time job and a family at home I'm affraid I won't find the time to live up to all of your suggestions, but thanks for thinking with me. My focus will remain to be on constructing a front wheel suspension that combines drive with aspects such as Ackermann steering, Camber angle, Caster angle etc. Making compromises will be inevitable, but if the result has some educational value (and of course does not fall apart while demonstrating) I will be satisfied. This also explains the minimalistic body; I want the suspension to have maximum room to travel under any steering angle. The educational purpose is also the reason why I don't plan to motorize this build. It's clear I have to go back to the drawing table when it comes to the front wheel hubs and their outer casing. I did manage to rearrange the outer casing such that the upper ball joint is fully lowered into the hub. This completely locks up the outer casing between the upper and lower wishbones (at the risk of labouring the obvious: the space between the upper and lower wishbones is fixed due to the vertical arm that connects the center of the upper wishbone with the center of the lower wishbone). However, the way the lower ball joint connects to the rest of the casing remains to be the weakest point of the setup. I will continue to search for improvement. About your suggestion to rotate the hub 90 degrees; I did investigate this, but couldn't come up with an appropriate setup. The lower ball joint would need to be placed beneath the hub, making the construction too large to fit inside the wheel, there would be no room to connect the lower suspension arm to the ball joint. Another aspect that narrows down the construction options is the fact that to obtain Ackermann steering the steering ball joint needs to be placed 1 studd to the inside of the car. When steering, this ball joint would bump into a vertical arm or shock absorber placed along the back side of the wish bones. This is why both the vertical arm and the shock absorber are both placed at the front side of the wish bones. The best compromise I found was to place the shock absorber as close as possible to the vertical arm. A push-rod-like shock absorber on top of the upper suspension arm would also be an option though. Anyway, thanks for the feedback. Helps me to improve this concept. I'll keep you posted... Regards, Diederik

Thanks! I use Bluerenderer: http://www.eurobricks.com/forum/index.php?showtopic=109972

The construction is of course a compromise. It does rely on the connector attached to the lower ball joint, which is indeed a weak point. If the hub would be a little larger, than the upper ball joint would already be completely pushed into the hub. In that case the vertical arm would lock up the hub and prevent the lower ball joint from getting disconnected. Ideas on how to make the hub an exact fit are welcome! Bear in mind that the hub needs space to turn en move up and down without touching the suspension wishbones, especially around the ball joints. Regards, Diederik

Update: I removed the images, the front suspension wasn't properly designed at this stage. As promised some pictures of and considerations behind the front suspension of the 'Steppenwolf': Kingpin inclination - To aim the projected axis of the steering down through the kingpin more towards the middle of the tire's width at the level where the tire touches the surface, the upper steering cup is moved 1M to the inside of the car while keeping the lower steering cup fixed. This reduces the scrub radius of the tyres. Zero scrub radius is possible without an inclined kingpin, but requires a deeply dished wheel so that the kingpin is at the centerline of the wheel. Lego wheels are not dished enough to have a vertical kingpin at the center of the wheel. Caster angle - To give the car a feeling of wanting to maintain a straight line, the kingpin leans slightly backwards. Variable camber angle - When the vehicle is in a turn, body roll should result in positive camber gain on the lightly loaded inside wheel, while the heavily loaded outer wheel should gain negative camber. Ackermann steering - A tooth rack with a fixed position with regard to the length of the car - it can only move sideways, not forwards or backwards - would weaken the effect of Ackermann steering when placed in front of the wheel axis. When placed behind the wheel axis, it actually amplifies the effect. Vertical arm - The extra vertical arm placed exactly halfway the upper and lower wishbones freezes the distance between the upper and lower steering cups during compression/expansion of the suspension. This locks up the self-assembled front hub and prevents it from getting disassembled during operation. Differential placed 0.5M in front - The differential is placed 0.5M in front of the wheel axis. This allows for a little more steering reach, because it gives the inner steering wheel some advantage on the outer steering wheel which is convenient because due to Ackerman steering the inner wheel will steer farther than the outer wheel. Suspension position under car's own weight - To make the overal suspension behavior a game of compression on one side and expansion on the other side, the normal suspension position under the car's own weight should be somewhat compressed. That will give the suspension some room to expand during operation. See also: https://bricksafe.co...olf/suspension. I'm curious what your opinion is about this. Regards, Diederik

Thanks for all the nice responses! More images of the front suspension are coming... I didn't plan to motorize it. I personally prefer to sense the drive while moving it by hand. But I can imagine their is space behind the seats and above the rear axles to place engines and a battery. Whohahaha! It does go back to the time when I started playing with Lego Technic though;-) I don't know whether I will be making real building instructions. I'm currently working with groups in LDD to have a building guidline for myself. I might offer those in the future. I will soon be posting close-ups of the front suspension. Regards, Diederik

This topic has been followed up here: http://www.eurobrick...howtopic=123304