Hrafn

@Carsten Svendsen my first thought would be to try https://www.bricklink.com/v2/catalog/catalogitem.page?P=44374#T=C doubled up it gives you 6 blades, then you can align successive pairs on the same axle at 30 degrees offset between each pair. But that gives you too much twist… hm. For augers, I have seen other builders use flex axles twisted in a helix around an axle, to give a sense of the auger’s edge.

@Jundis, neither. I would use 12z double bevel gears instead - the knob wheels wear quickly and I have been told they are inefficient because they don’t mesh closely.

Between https://www.bricklink.com/v2/catalog/catalogitem.page?P=87408&idColor=11#T=C&C=11 and the portal axle? I would try that out and see if it is feasible before worrying about the placement of the servo - you are cramming a lot of complexity in there.

@Technic tango how were you planning on steering that swing axle bogie module? Can you use skid steering on it?

Fair enough! 😁

As usual I have over-complicated things. Have a motor drive one side of a differential; have the output be the other side; add friction to the housing by meshing it with a gear on a friction pin. When the output is blocked because the lift has reached the top or bottom, the housing will spin instead of the output. You can switch any of the elements around - the motor could dive the housing, or the housing could drive the output.

I think so. A lot will depend on the motor, gearing, and load on the output axle. You could use a return to center mechanism like the hockey spring, or, better, Sheepo’s return to center system (I would link to it but his site seems to having issues).

Here is a purely mechanical proof of concept, which works no matter which way the motor is turning. The motor is attached to the red liftarm (Bricksafe cropped the picture). The motor remains on all the time, but when the output axle (with the lime connector and 20z gear) is blocked, the differential housing is blocked as well, and the orange gear selector disengages the red clutch plate from the gray clutch gear. The dark gray 2L liftarm is blocked from rotating more than 90 degrees either way, and acts as a manual switch to re-engage the output axle when desired. Construction notes: The clutch plate is on a smooth 2L axle joiner, not a ridged one. Obviously you would need a rigid structure- this just shows the positions of the parts. And the orange gear selector tends to rotate slightly even when the output isn’t blocked, so it needs some friction or a rubber band or spring to resist that tendency.

For a pure PF solution, connect the motor to one side of a differential, and the PF switch to the other. Drive your mechanism from the differential housing. When your mechanism reaches its limit, the motor will drive the switch, turning itself off. https://bricksafe.com/files/Hrafn/technic-misc/trim.5D0469E9-E870-4EB2-8010-7C0F3476E099.MOV Note that this isn’t a 100% solution since it only drives your mechanism in one direction.

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Great stuff! Is the front suspension based on the TC18 Porsche by @Limga?

This is really great. Thanks for sharing the suspension details, it is a very clean build in this scale. As for terminology, TC18 is a little cryptic, but specific; I have seen it called mid-scale as well. I too wold like a common term for it as I am working in this scale as well.

Such clean bodywork! I would love to see a video or gif of it moving.

I hear you. Maybe if the two parts directly under the headlights were white instead of black?

Making excellent progress! The one thin I am not sure about is the grill - the bit with the Bionicle teeth reminds me of longhorn cattle, which doesn’t fit the rest of the car IMO. Can you maybe flip that portion upside down?

😂 I hear you on that! As soon as I post something I invariably realize the flaws with it.

Thank you for providing and updating all of these tools, and letting people know about the updates. I have found the wheel tool especially helpful.

The bodywork looks so good! I like the linkage holding the hatch in the up position- it is a nice little touch.

Thanks for getting the pics to work. I would use 1:8.4 scale, because a model with wheels that are too small will look odd; the reverse is not true, as slightly oversized wheels usually look ok.

Your images did not upload.

I was experimenting with the 14 tooth gears because when using 2 gears, if the gears have a number of teeth divisible by 4, you get an angle between thee input and output shafts (15 degrees if using 12z gears.). With a servo, this is undesirable because when the servo is in a neutral position, the steering shaft is not. The 14z gears can be oriented to avoid this issue. I ended up finding a compact solution using the PF-M and Sheepo’s recommended return to center steering solution; it works well in isolation but I haven’t tested it integrated with the rest of the vehicle yet. The steering doesn’t _have_ to go in the glovebox, but I wanted to see if I could make it work so that there was room for a full interior. At this scale a servo would be too large to really look like a center console.

The bodywork looks good! It has strong kei car vibes to me, a little reminiscent of the Autozam AZ-1 crossed with a Miata.

In the Technic gear lineup, there are the old 14-tooth gears, which I have used precisely for this reason.

Good point. Also, getting the car to go straight would be difficult. Maybe I just need a different RTC mechanism that requires less power to overcome, so when the PF-M stalls, the stall current isn’t too great. Maybe the one that uses two 2x4 L-shaped liftarms. A servo solution would be even better if someone can figure out how to make it compact enough.

@That_LEGO_Guywhat is the red part in the front suspension?