Since I got such quick and helpful advice on my piston rod question, here is my next challenge: universal joints!

Specifically, how do I work out the compound angles of a double u-joint connection? See the image below, where I need to connect axle A to axle B by using the short connecting axle that's floating nearby.
   

Here are some parameters:

• Axle A is oriented parallel the model's Z axis; axle B is oriented at an angle to it. The connector will have to be rotated in both the X and Y directions, but you can't just set one and then the other, because changing either affects both. I'm guessing the 't' word, trigonometry, will come in again here, but because of the compound angle, I'm not sure where to place the triangles.
  
• Axles A and B are rotated 22.5 degrees with respect to their longitudinal axes; my assumption is that the U-joint will transmit the same angle to the connector axle, and that while this rotation needs to be accounted for, it won't change the method needed to determine the connector angle.
  
• I guess I need to determine the rotation of the U-joint hubs at A and B, around both of their local X and Y axes. Again, my assumption is that the hubs themselves, however they may be rotated, will always remain at the same coordinates in absolute space; that is, they always form the point around which the connector axle is angled at each end.
  
• The end of the axle at B may need to be slid downward along its own longitudinal axis in order to correctly intersect the connector axle; this unknown position makes the trigonometry harder to figure out for me.
  

To say the least - I have something left for the era of steam engines.



Especially these time, where the Art Deco has been founded - although my love belongs to the "Art Nouveau",

... also termed in German as "Jugendstil".



Simple marvellous!



So I built this steam locomotive - so as this "Lady" should look like,  trying to reach a maximum from the real original shape....

..as a relict of those nostalgic "Golden Times".



LDraw delivers some benefits, such as "no Dustcatchers" or "room murdering Vitrines", no Limitations of Brick parts amount or unavailable colors.

Also custom parts, patterns or stickers can be designed without any problem.



Always lovely to begin a new project



So, here it is:



Built in th Year of the Lord 1923 and

highlighted with technical performance-enhancing conversions and with representative paint, this machine was first exhibitioned 1925 in Paris, at



"Exposition Internationale des Arts Décoratifs et Industriels Modernes"



Original:

Name: Gt 2×4/4

"5773"

Later Termed  : BR 96

Indicated Power: 1630 PSi



Model:

1 x Buwizz

2 x original medium motors

2 custom Parts: Wind deflector on the cab, drive rod

1 modified part: 3,2 mm pierced 49098.dat (Chimney collar)

a big bunch of patterned parts

BBB Train Wheels

   
   
   
   

Hi Team,

I've created Tail 2340p030 but the surfaces seem to lose their relationships (?) when imported to Blender using the LDR import plugin.

The part was created using LDPE to create left and right templates for use in LDPC, then patterns created. These left and right patterns where then added to the subfile of 2340s01.

         

The created part imports into Stud.io correctly but subsequent export/import into Blender seems to break the part apart.

   

What term/technique have I overlooked or misunderstood?

I've actually created all of the "Canada" series printed bricks and am happy to submit them once this piece is complete.

Thanks in advance.
Adam

Attached Files

  2340pb030.dat (Size: 69.11 KB / Downloads: 3)

Over at the Stud.io forum there was an entry concerning the missing stud-logo on an old part, namely 50949.
I check it and noticed that the primitive is in upper case (STUD.DAT) that leads the renderer to ignore the substitution. Upon changing it to lower case the LEGO-logo was rendered.
   

Do we have an overview how many files still have uppercase prim in them? Shall we recycle them?

Since, although this part appears in only a single set (5571 Giant Truck), that set seems to be a favorite model for many of us, I thought I'd officially request the wheel hub that missing from the library:

https://www.bricklink.com/v2/catalog/cat...4a#T=C&C=9

Happy to work on it myself…but that will be sometime in the future after I get (much) more familiar with parts authoring!

«AWESOME LDraw» is curated list of LDraw resources, such as apps, 3rd-party parts libraries, tutorials, everything related to digital lego modeling.

I created a new LDConfig file using RGB colors from LDD:


  LDConfig.ldr (Size: 32.34 KB / Downloads: 14)

with the following conventions:

* LDraw and BrickLink mostly share naming conventions for their colours.
* Where possible LEGO colour numbers were used.
* The LEGO numbers, names and LDD colours are taken directly from LEGO Digital Designer.
* Colours were compared with Ryan Howerter colour list.
* Rubber colours got their value from the correspondent solid or transparent colour.
* Some transparent colours were altered so that they can be displayed with their LDraw alpha level.
* Edge colours for solid, pearl, metallic colours were calculated the following way:
  If the lightness value L in the HSL colours system was above 20% a Gray with 20% relative
  luminance in the terms of RGB-Gray was used.
  If the lightness value L in the HSL colours system was below 20% a Gray with 50% relative
  luminance in the terms of RGB-Gray was used.
* Edge colours for transparent, chrome, glitter colours were calculated the following way:
  The lightness value L in the HSL colours system was lowered by 20 %. If the lightness value L in
  the HSL colours system was below 20% it was rosen by 20%.

What do you think of it?

Philo kindly compiled a corresponding visual file:



The old version for comparison:

I tried to load a model and found that a number of Bionicle and Factory parts where not available for LDraw.
If someone could make these, I would really appreciate that.

LDD number    Bricklink number    Bricklink description
41890    41890    Arm Mechanical, Super Battle Droid
98570    98570pb01    Hero Factory Chest Badge with 'H' on Light Bluish Gray Background Pattern
98562    98562    Hero Factory Weapon - Handcuff
47299    47299    Bionicle Toa Metru Knee Cover
19179    19179    Minifigure, Weapon Blade with Bar and 3 Spikes
92222    92222    Hero Factory Shield with Handle for Clip
15407    15407    Minifigure, Hand Armor
47298    47298    Bionicle Toa Metru Foot
98564    98564    Hero Factory Zamor Sphere Launcher - Bottom Half with Axle Hole
98593    98593    Hero Factory Shoulder Armor, Sonic Speaker
98341    98341    Ring 4 x 4 with 2 x 2 Hole and 4 Arrow Ends (Ninjago Spinner Crown)

Thanks in advance,

René

https://youtu.be/4cvr20Q39gw

New parts @ 4:13

I can't quite figure out how to calculate the angle and vertical distance of a piston rod on a rotated crankshaft, specifically using LDCad's Selection Info tool. Here's a diagram:
   

So the crankshaft has been rotated -49.5 degrees. The piston rod (A-B) will move up the Y-axis, but I don't know that distance (it's slightly less than the current Y distance between A and C). Also, point B will remain at its current X position but point A will rotate around point B to connect with the axle at point C. The angle of that rotation is the second thing I don't know.

No doubt this has been tackled many times before, but I'd like to know the precise way to figure it out (rather than downloading an already finished model). It's either slightly more difficult, or vastly simpler than I realize.   (And I do know about the piston placement script in LDCad, but AFAIK it doesn't recognize these old-style piston parts or brick-built cylinders.)

Again, the two values I need to find are:

• The distance to move the piston rod along the Y-axis, and
  
• The angle to rotate point A around point B so that it connects with axle C