Bicolor legs

[Philippe Hurbain]

Could anyone here read the design number hopefully embossed on bicolor minifig legs such as https://brickset.com/parts/design-21019 ? 21019 is the design number of the hips+legs assembly, but I'd like to know the number for the left/right legs. Probably different from 3816/3817 as it's a different injection process.

[Philippe Hurbain]

Could anyone here read the design number hopefully embossed on bicolor minifig legs such as https://brickset.com/parts/design-21019 ? 21019 is the design number of the hips+legs assembly, but I'd like to know the number for the left/right legs. Probably different from 3816/3817 as it's a different injection process.

Stupid me... just had to look in LDD! 20460 / 20461

[Magnus Forsberg]

Could anyone here read the design number hopefully embossed on bicolor minifig legs such as https://brickset.com/parts/design-21019 ? 21019 is the design number of the hips+legs assembly, but I'd like to know the number for the left/right legs. Probably different from 3816/3817 as it's a different injection process.

Stupid me... just had to look in LDD! 20460 / 20461

from LDD: 21019 (complete assembly, hip + legs)

exported: 20460 (left leg, complete) + 20461 (right leg, complete)

printed embossed inside:   20926 (left foot) + 20932 (right foot)


As I wrote in a part review somewhere, I don't think we will ever have a "third" partnumber on a dual injected part.
The first mould create 20926, in this case. The second injection will be into the second mould 20460, where the first "part" is allready placed. IMO the first "part" has to be treated as a sub-part, and there shouldn't be any edges between the two "halves".

[Magnus Forsberg]

I think we might need to set up some rules about how to treat, and talk, about these parts.

Are the two halfes Parts or Subparts?
Could a Part (with its own partnumber) be only placed in the s-folder?
These two coloured parts should not be treated as Shortcuts.

There is a difference between a dual injection and a two step injection.

• Dual injected parts use one mould, but are injected with two, or more, colours at the same time, thus creating a blended, swirly, mixtured coloured part.
  
• Two step injected parts use two, or more, moulds, and are injected at two separate occations, thus creating a very distint line between the two colours. That line is always at the same exact place in the design.
  

My first comments and thinking was made here:
http://www.ldraw.org/cgi-bin/ptdetail.cg...326p01.dat

[Philippe Hurbain]

I think we might need to set up some rules about how to treat, and talk, about these parts.

Are the two halfes Parts or Subparts?
Could a Part (with its own partnumber) be only placed in the s-folder?
These two coloured parts should not be treated as Shortcuts.

There is a difference between a dual injection and a two step injection.

• Dual injected parts use one mould, but are injected with two, or more, colours at the same time, thus creating a blended, swirly, mixtured coloured part.
  
• Two step injected parts use two, or more, moulds, and are injected at two separate occations, thus creating a very distint line between the two colours. That line is always at the same exact place in the design.
  

My first comments and thinking was made here:
http://www.ldraw.org/cgi-bin/ptdetail.cg...326p01.dat

For me: halves as subpart, for both injection methods. Not a shortcut, a full fledged part.
(edit: I read later your first comment, looks like we mostly agree)

[Magnus Forsberg]

No, I think it should be like this:

The first half is a Part, to be placed in the Parts-folder. It has its own partnumber.
The second half is a subpart, to be placed in the s-folder.

The two halves are together a Part, to be placed in the Part-folder.
A two coloured Part = (Part + subpart), and this is not a Shortcut.

Is there already another example like this, where we have a Part inside a Part without it becoming a Shortcut?


  legs.png (Size: 9.03 KB / Downloads: 124)

[Philippe Hurbain]

No, I think it should be like this:

The first half is a Part, to be placed in the Parts-folder. It has its own partnumber.
The second half is a subpart, to be placed in the s-folder.

The two halves are together a Part, to be placed in the Part-folder.
A two coloured Part = (Part + subpart), and this is not a Shortcut.

Is there already another example like this, where we have a Part inside a Part without it becoming a Shortcut?

I sincerely think that this scheme is needlessly complex. No benefit over using two subparts.

[Magnus Forsberg]

btw,

Are you working the LDD data, or are you cutting apart the reworked, corrected legs from Nils, 3816b and 3817b?
The LDD data is equally incorrect as the old legs 3816 and 3817.

[Philippe Hurbain]

btw,

Are you working the LDD data, or are you cutting apart the reworked, corrected legs from Nils, 3816b and 3817b?
The LDD data is equally incorrect as the old legs 3816 and 3817.

I'm using Nils' geometry. Soon on PT...

[Philippe Hurbain]

I sincerely think that this scheme is needlessly complex. No benefit over using two  subparts.

Another point that I think is in favor of all subparts: parts are supposed to be a closed volume. But adding internal separation between colors would not only add useless complexity, it would also cause bleeding.

[Magnus Forsberg]

I would like to hear from a third party here.

[Willy Tschager]

For me: halves as subpart, for both injection methods. Not a shortcut, a full fledged part.

+1

[Magnus Forsberg]

Could anyone here read the design number hopefully embossed on bicolor minifig legs ...

I can't drop this issue yet.
Looking at your original question again, forces me to question the numbers on the subfiles used in these legs.

I think we have an agreement on How these parts should be made.
Use subfiles,
don't add edges between the two colours
don't add any hidden structure that might cause unwanted surface bleeding.

The question I can't drop is the partnumbers of the included part, and its subfiles.
Should we really ignore the embossed number that a user might find inside a two coloured part?
Or should/could some of the subfiles have a different partnumber?

How do we describe that partnumber 20926 is included in partnumber 20460.
How do we handle that the number embossed inside a two coloured part is not the number a user should search for?


As two coloured parts are getting more common I think we need some sort of handling strategy here.

[Philippe Hurbain]

Should we really ignore the embossed number that a user might find inside a two coloured part?

Good point. I suggest to use that number (if and only if it is embossed) as a keyword in the part. Naming subpart accordingly to that number would be useless as a normal user will never see it.

[Gerald Lasser]

One more thing concerning those two colored legs which come printed
- Shall we construct these parts the following way:
- Create a leg by using both subparts without surfaces and add the print

or
- Create a leg by creating two seperate subparts useing the respective surface-less sub-parts and print.
- Join the printed top and bottom in a part?

What do you think?

[Philippe Hurbain]

One more thing concerning those two colored legs which come printed
- Shall we construct these parts the following way:
- Create a leg by using both subparts without surfaces and add the print

or
- Create a leg by creating two seperate subparts useing the respective surface-less sub-parts and print.
- Join the printed top and bottom in a part?

What do you think?

Not sure it really matters. I feel the second method is slightly better as it keeps separation between two differently injected halves, but for a pattern that extends in both areas it makes the patterning job a bit more difficult.

[Magnus Forsberg]

I see no reason to split a pattern printed spanning both halves.

But I have another question: 
Do we need a ruling on what half of the leg that should be hardcoded?
On the sleeved arm we dicided to hardcode the lower arm in yellow, but it has been later  divided into
many more subfiles to allow print on different parts of the arm.

In fact,
Is there anything that determines which part of a multicoloured part that should be hardcoded?

[Philippe Hurbain]

Is there anything that determines which part of a multicoloured part that should be hardcoded?

imho, the best to choose hardcoded part to minimize the number of assemblies needed (hoping that the ratio will not change with time )
Here I think that the hardcoded part must be the boots, because most of the time the hips and top of legs have the same color.

[Magnus Forsberg]

btw.

What number should be used on the hips+legs assembly?
3815bc01 is already used and now we have two coloured legs that use p01 and p02.

[Philippe Hurbain]

btw.

What number should be used on the hips+legs assembly?
3815bc01 is already used and now we have two coloured legs that use p01 and p02.

Maybe 3815bp01c01, 3815bp02c01, etc... ?

[Magnus Forsberg]

Maybe 3815bp01c01, 3815bp02c01, etc... ?

I think we should use the same number lego has on this assembly, with a pattern suffix.
21019 = 3815b + 20460 + 20461 (uncoloured base file)
21019p01 = 3815b + 20460p01 + 20461p01

Or should it be: 
21019cXX = 3815bpXX +20460pXX + 20461pXX (an assembly suffix gathering the printed parts)


Since we know that the old legs, 3816+3817 have a bad geometry and need a rework and a move to 3816b+3817b, I think we need to stay away from the 3815bpXX, or cXX, assembly shortcuts.
The hips+legs with corrected geometry are on the PT, but all the printed hips+legs need to be moved, at some time.

[Philippe Hurbain]

21019p01 = 3815b + 20460p01 + 20461p01

Agreed. I like this one. c01 doesn't really make sense as 21019 IS a composite shortcut.