How to apply part markings

This article explains how to add markings to your 3D assembly in MasterShip. You'll start with a detailed 3D assembly that already includes part data. By applying marking lines and text, you can transform your model into a clear build kit. This process is crucial for minimizing errors in the workshop and optimizing logistics at the shipyard. Essentially, you'll be adding visual cues to indicate how parts connect and providing essential part information directly on the model.

Did you know? Effective part markings can significantly improve the quality control process, as any discrepancies can be easily identified during the assembly phase.

Adding markings to plate parts in MasterShip

This video demonstrates the functionalities MasterShip has to offer for marking parts. Next to that, we have listed some of the best practices from the engineering perspective below:

• Timing of marking: Start marking after the detailed construction is done and approved. This prevents mistakes in the marking process and potential rework.

• Marking of connecting parts and stiffeners: Add marking lines for connecting parts and stiffeners to indicate the position, thickness direction and PosNum of connected parts and stiffeners. This practice can transform your 3D model into an efficient build kit. Having the positions of connecting parts marked, saves a lot of mistakes and overhead from looking at construction drawings and sorting out parts.

For automated marking of connecting parts and stiffeners within the same drawing, utilize SHIPMARKPARTS and SHIPMARKSTIFFENERS. To automatically mark connecting parts and stiffeners from other drawings, use SHIPMARKADJACENT. This is a great time saver. When using automated tools, always check the results for correctness.

The commands SHIPADDPARTMARKING and SHIPMARKINGTEXT enable you to apply any form of generic marking lines or text. Also, SHIPPARAMIDMARKING is a simple yet effective tool to specify part or stiffener direction.

• Defining beveled edges on parts: Bevels are defined on parts where the adjacent plate thickness differs by more than 4 mm. Bevels are essential to ensure proper welding and assembly. The SHIPMARKTEXT command in MasterShip can be used to mark the bevels on the parts. 

• Marking of positioning lines: Mark positioning lines on the part every 500 mm for waterlines and verticals. Smaller parts should have at least one vertical and one horizontal marking line. These lines provide reference for assembling all the parts in the workshop. 

SHIPADDMARKINGGRID can be used to mark a 'grid' on your part. This is particularly useful for big parts, such as decks and bulkheads.

• Consider on which side to mark: If there are a few connecting parts on the other side of the part, relative to the viewing direction, then the marking lines for these parts can be drawn dashed and indicated with an 'OS' text marking. 

If the majority of the connecting parts are on the other side of the part, the part can be marked as usual and put upside-down in the nesting. This practice prevents you from too many dashed lines that might need to be transferred to the other side of the plate by hand later, and enhance a clear view.

For these situations you can check the box 'Mark on other side' from the part data dialogue window in MasterShip, and apply your markings as usual. By using this function, the markings will show up in purple color instead of green color in the sectional drawings, and the part will be nested upside-down.

• Mark openings on parts and cut-out after assembly: Sometimes it is desired to cut-out an opening on site, after the plates are assembled. This is done to prevent misalignment issues. For example a door or a hatch in a deck is nice to cut-out after the deck plates are welded together. It can be beneficial to partly make the cut-out while CNC-cutting, by using dashed cutting lines. This goes especially for more complex shaped lines (such as rounded corners), or to save time in making the final cu-out.

• Mark part information: This enhances the logistics on the shipyard. Having a part ID (PosNum), production unit and any treatment information helps sorting out parts.

In MasterShip, this is typically done after the plate nestings are made. Using the command SETTEXTINTPLATE you can get the part information as marking text in the plate.

Expert tip: In MasterShip, the default is "partID / Production unit - sub assembly / operations". To tailor this data to your shipyard, you can modify the format and amount of part data to print on the part. Here is how: How to modify marked part data.

• Marking bending and folding lines: Clearly indicate bending or folding lines and dimensioning to facilitate correct and efficient part processing.

• Indicate chamfer at plate edges: This is done using text marking on the edges. Chamfer is used when there is a relatively big difference between the thickness of two hull plates.

• Prevent cluttering the part: Too many markings can make the part difficult to read.  For this sake, it might be that not all these best practices should be implemented, but at least considered.

Marking hull plate expansions and molds

All of the above practices apply to hull plates expansions and molds too. Though, there is a 'catch'. With hull plates expansions, marking lines are always to be created during the expansion process. Not afterwards, as is the case with the rest of the ship's construction. Therefore:

• For hull plate expansions: Always expand marking lines from 3D to 2D too. Applying marking lines manually after the hull plate is expanded, will almost always be wrong. 

In MasterShip, hull plate expansions are made with the commands SHIPDOUBLECURVEDEXPANSION and SHIPSINGLECURVEDEXPANSION directly from the 3D model. While using these commands, the user is always asked to select positioning lines to be marked from the 3D model. This way, the marking lines are also expanded an exactly at the right position.

• For molds: Apply text marking on both the molds and the plate expansion to indicate their positions.

Output and next steps

By implementing these marking practices and utilizing MasterShip’s tools, you can significantly enhance shipyard logistics, reduce on-site errors, and improve overall production efficiency. The resulting detailed 3D assembly model, enriched with production data, provide a solid foundation for subsequent nesting operations.