Nomenclature

Nomenclature for screws

Nomenclature: Screw length_(LDu) x thread_diameter_(LDu) {head type} {slot type}

At present we have the following {head type}:
- Countersunk
- Pan
- Flat
- Beveled
Screw length is measured from the flat underside of the head, except for Countersunk when it is measured from the flat top surface.

At present we have the following {slot type}:
- Slotted
- Cruciform
- Triangular

Examples:
u9000.dat - ~Screw 44.5 x  5 Countersunk Slotted
u9013.dat - ~Screw 12 x  6 Pan Cruciform
u9021.dat - ~Screw  6 x  5 Flat Slotted
u9022.dat - ~Screw  4 x  4 Beveled Triangular
--Mikeheide 09:56, 10 July 2011 (EDT)

Nomenclature for tyres

Nomenclature: width_(mm) / profile_as_%age_of_width x rim_diameter_(mm) [optional qualifier]

Please note that this dimensions has to be in mm!

This text needs to be extended with some information about measurepoints for the dimension.
Original LUGNET discussion is at http://news.lugnet.com/cad/?n=13760

Examples:
50951.dat - Tyre  6/ 30 x 11
87697.dat - Tyre 12/ 40 x 11 Wide with Center Band
u9131.dat - Tyre  7.2/ 45 x 8.8
--Mikeheide 10:11, 10 July 2011 (EDT)

Unit of Measure differences ?

Why are wheels and tyres in mm but screws are in LDU? ++Lar: t/c 17:47, 11 July 2011 (EDT)

I don't know. Are they? Have to investigate. --Mikeheide 00:46, 17 July 2011 (PDT)

They seem to be... see Nomenclature for screws. ++Lar: t/c 12:10, 17 July 2011 (PDT)

I have take that from a part on the PT. I think Chris has written that. But I see no reason to change as measuring in mm/inch is quite more difficult. With this approach you can much easier find a screw that already exists and fit your needs. IMHO.--Mikeheide 00:07, 23 July 2011 (PDT)

So maybe it's wheels and tyres that are the odd man out then. Changing them is more extensive I suppose. Also many LEGO tyres have the size imprinted/molded in the rubber. ++Lar: t/c 05:57, 23 July 2011 (PDT)

We have a mix of units across the library (studs/brick height units/LDu/actual) and it doesn't make sense to use a single unit for everything. I deliberated long and hard on the tyres, to help solve the problems of small/medium/large that existed. In the discussion at http://news.lugnet.com/cad/?n=13760 I decided to go with something that most closely matches the commercial (ISO) nomenclature, which is in some cases used by LEGO. Cwdee 21 August 2011 [P.S. I didn't find any reply interface, so edited the page directly - is that how this Talk thing works??]

Thanks for the explanation, and yes that's how replying works... talk pages are just like any other pages (unless the wiki has installed Liquid Threads, which this one hasn't and which I advise against). Note, you may want to consider setting your signature so that when you go ~~~~ in your post it autoadds a signature. Mike and I have that set already. It's in your preferences. ++Lar: t/c 11:31, 21 August 2011 (PDT)

Thanks cwdee 12:09, 21 August 2011 (PDT)

Nomenclature for wheels

Currently there is no Nomenclature for wheels that we agreed on. So the following is only a suggestion from me.

Nomenclature: width_(mm) x rim_diameter_(mm) [optional qualifier]

Please note that this dimensions has to be in mm!

This text needs to be extended with some information about measurepoints for the dimension. The same measurepoints has to be used also for the tyres

--Mikeheide 10:20, 11 July 2011 (EDT)

Use of leading space for numbers

The reason for using leading space in front of numbers lower than ten (10) is the sort order in listings.
Example: (wrong order)
Brick 10 x 10
Brick 2 x 2
These two description would be in a list just the wrong way because the seventh character (as it is the first different) will decide about the sort order.
So if we add a whitespace in front of the 2 we have "whitespace" and "1" at the seventh character. Because the "whitespace" has a lower internal value as the "1" the correct sorting order will be visible.
To show it visually here I had to substitude the whitespace by underscore.
Example: (correct order)
Brick__2_x__2
Brick_10_x_10

As this has not been considered from the beginning of the library there are little inconsistances in the library.
I like to mention here what I had discovered so far that does not follow the simple rule - "If number is used and number is lower than 10 use a second whitespace in front of that number":
at parts and subparts

• if the word 'type' is the last word before that number (Baseplate 32 x 32 Road 9-Stud Landing Pad Type 1 (Orange) - [1])
• if the word 'Road' is the last word before that number and the letters '-Studs' are direct attached to the number (Baseplate 32 x 32 Road 9-Stud Landing Pad Type 1 (Orange) - [2])

My earlier resumee at this place has been wrong. The real old part with L, V, H and / direct after the number do have a leading whitespace. And that makes sense to me because of the sort order.(2011-06-25)

at primitives

• if word 'Torus' is in the description only the first of the numbers needs a leading whitespace
• if word 'Circle' is in the description none of the numbers needs a leading whitespace
• if word 'Cylinder' is in the description none of the numbers needs a leading whitespace
• if word 'Cone' is in the description only the first of the numbers needs a leading whitespace
• if word 'Ring' is in the description only the first of the numbers needs a leading whitespace
• if word 'Disc' is in the description none of the numbers needs a leading whitespace
• if word 'Chord' is in the description none of the numbers needs a leading whitespace

If you have an original part that does not fit into this scheme please inform us. Please do not use the parts on the PT as reference because there are parts that follow not these rules maybe because of the usage of DATHeader.
To bring DATHeader in a good condition I like to have this cleared if possible.
The soon coming version 3.0.8.0 of DATHeader will act as described here but without a correct check on the primitives.

--Mikeheide 16:32, 24 June 2011 (EDT)