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Thread for the inaugural year of Technic sets.
853/956 - Auto Chassis (main model)

[attachment=4084]

My first model submission!

No known errors, but a few spots are "unbuildable" in LDraw, because they depend on the natural tolerance of physical plastic (common among early Technic/Expert Builder sets):
  • Where the steering tie rods join the control arms, the pins are not "in click" with the 2x4 Technic plates.
  • The inclined 1x8 Technic bricks of the steering column are slightly out of alignment at their upper connection point.
  • The rear suspension "struts" are well out of alignment at their upper connection point, such that the 4L axles are considerably compressed into the toggle joints.
OMR compliant, made with LDCad 1.6c (under Wine)
Nicely done!
851/952 - Tractor

Tractor with one of the equipment attached. The other ones are also in the file.

Tyres in color Rubber-Black

OMR compliant according to MPDcenter tool.

Build with MLcad 3.51
In equipement 1 the driving axle
Code:
1 0 -25.5 -48 -5 0 -1 0 1 0 0 0 0 1 3705.dat
is placed too high, it collides with top plate and doesn't enter in the hole of bottom plate.

Also, since the model is shown with equipment 1, I think that the attachment beams of tractor should be configured/rotated so that the small wheels of equipment 1 sit on floor (and so that the top 40t gear properly mesh with driving crown gear of tractor)
852 Helicopter /954 - Sky Copter

OMR compliant according to MPDcenter tool.
Added updated file.

Build with MLcad 3.51
(2020-03-21, 8:26)Philippe Hurbain Wrote: [ -> ]In equipement 1 the driving axle
Code:
1 0 -25.5 -48 -5 0 -1 0 1 0 0 0 0 1 3705.dat
is placed too high, it collides with top plate and doesn't enter in the hole of bottom plate.

Also, since the model is shown with equipment 1, I think that the attachment beams of tractor should be configured/rotated so that the small wheels of equipment 1 sit on floor (and so that the top 40t gear properly mesh with driving crown gear of tractor)
Hello Philippe,

Thanks for the comments. Apologies for the 'mess'. I clearly missed some clean-up actions.
This file should have corrected all your points and more I found myself.

When get files added to the overall list of official models?

Regards Allard
(2020-03-21, 13:31)aefferen Wrote: [ -> ]Hello Philippe,

Thanks for the comments. Apologies for the 'mess'. I clearly missed some clean-up actions.
This file should have corrected all your points and more I found myself.

When get files added to the overall list of official models?

Regards Allard

Still looks like some gears not meshing properly in the implement—in the first place, the whole implement is about 5 LDU off-center in the X direction. Then, the top 40t gear would have to be rotated by half a tooth to mesh with the crown gear. Finally, the two side "blades" of the implement will have to be rotated to mesh with the center one (which should end up being correctly oriented once the above problem is fixed).

Also, I spotted some extraneous 1x4 beams attached to the rear axles of the tractor, duplicating ones found in the lever-1 submodel. And, is there any particular reason to have the model's origin (0,0,0) so far away?

Finally, the steering column isn't fitting inside the 1x2 beams that hold it—this is always a tricky problem with these sets. And something's wrong up front, where one of the 8t gears is colliding with the 1x2 brick holding the axle. Looks like both gears just need to be slid backward.

Sorry to pick apart so much! Technic models are definitely challenging because of stuff like this, but that's where the fun (?) is with them.  Smile  And I've certainly had invaluable help from other members of this forum in solving some of these challenges. You're welcome to have a look at my version of the tractor model (attached) if it's useful at all.

As for when models get added, I think it's a weekly process, though in my experience it seems to be quicker than that, once everything's compliant of course. On that note, the OMR spec does have guidance about file structure for sets with alternate builds—would that apply to the different attachments in a set like this? If so, I guess there should be a separate MPD file for each version, named according to which implement is attached—but good luck figuring out which real-world implements each one is supposed to represent!  Wink
[attachment=5007]
(2020-03-21, 16:29)N. W. Perry Wrote: [ -> ]Then, the top 40t gear would have to be rotated by half a tooth to mesh with the crown gear. 
To be honest, I almost never go to the trouble of meshing gear teeth...
(2020-03-21, 19:39)Philippe Hurbain Wrote: [ -> ]To be honest, I almost never go to the trouble of meshing gear teeth...

I do if it's not too bad but mostly I don't either.
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