Female mould GRP exampleMaxsurf provides a method for specifying skin thickness and material properties that are consistent and compatible with both Hydromax and Workshop. This also allows sections with skin thickness deductions to be displayed in Maxsurf, printed from Maxsurf or exported to a DXF file.
Thickness can be either specified directly or selected from the Material pop-up menu. The Material pop-up menu will contain materials that have been loaded from the Workshop materials library. Workshop may be used to modify the library; users who do not have Workshop will have the default library.
The direction that the thickness projects from the line of the designed surface needs to be specified. Three choices are available:
· inside the designed surface
· centred on the designed surface
· skin outside the designed surface.
To do this Maxsurf needs to know what the inside and what the outside of each surface is. Make sure the Outside Arrows are set up correctly (pointing outwards, generally towards the “wet side” of the vessel). For more information on outside arrows see Outside Arrows on page 100.
Note: Skin thickness and hydrostatic calculations
In Maxsurf skin thickness is used for creating the table of offsets, however for hydrostatic calculation purposes, skin thickness is ignored. Hydromax can be used to calculate the effect of skin thickness on the vessel’s hydrostatics by selecting “include skin thickness” in the opening dialog.
An example of a thickness deducted inside the hull would be a hull made of foam sandwich, where the Maxsurf surface modelled the outside of the hull. The skin thickness deduction would then give the line of the inside of the foam core and laminations.
Female mould GRP example
A typical steel or aluminium boat is designed to a moulded line, to the outside of the framing, but the inside of the hull plating. Another example is a GRP boat build from a male mould. The Skin Thickness would then be added on to give the line of the outside of the plating.
Frame construction method (Same for male GRP mould method)
Plating centred around the designed surface would be unusual for the hull shell, but has been included for possible use in the specification of internal structure.
You can see the effect of the skin thickness and direction you have specified by displaying deducted sections. To display deducted sections
· Choose Contours from the Display Menu and select Deducted Sections.
If this option is selected, deducted sections will be displayed on screen and included in DXF and IGES file output.