Designing with Fully Surfaced Mold Blocks in XMD-S

Solid mold blocks have become such a hit in XMD-S, users have started to ask us if there’s any reason to keep the part and parting line sheet bodies that XMD has traditionally relied on.  We’ve looked into it, and with release 4 of XMD-S, we’re proud to say that you’re free to kill your surfaces — take solid modelling all the way!

This article will explain the different ways of working with surfaces in XMD, and the pros and cons of each.

Free Surfaces

Integrated Surfaces
Using your surfaces as separate sheet bodies is the mode that XMD has traditionally operated in. XMD will read this geometry and treat your mold blocks as if they were trimmed to it. 

For example, holes in the core block will not be created above the surfaces, even though there is quite a bit of core block solid above them.

 XMD-S fully-supports working without separate sheet body surfaces. XMD-S understands which faces of the mold blocks make up the part and parting line surfaces. 

As of XMD-S 9.0.4, this method of operating is completely supported.  Read on to learn more about this exciting new feature.

Why Free Surfaces?

Why Integrated?
Freedom and flexibility. 

  • You are free to start the mold design immediately by putting the part and a roughed up parting line (if available) on the proper start-up levels.
  • You can use part references to reduce memory, and get faster load and save time.
  • Poor part data won’t have as much of a negative impact.
  • Fewer issues with model editing, particularly for those that prefer to work with automatic holes turned on.
 Power and precision. We recommend this for most cases. 

  • On average, solid modeling is much easier than surface modeling.
  • Much easier to visualize the final product.  Understanding what XMD is looking at is more straightforward.
  • Solid errors are more likely to be caught upfront.
  • Surfaced blocks are always ready to be exported and can be read more clearly and efficiently by other CAD/CAM software.
  • It shows your company’s professionalism and that it is up-to-date with current technologies.
  • If your modellers work with solids, you might as well too!

Free Surfaces FAQ

Integrated Surfaces FAQ
Where does my part go? Level 100.1 for the cavity side of the part, and 200.1 for the core side. 

Where do my parting line surfaces go? Levels 100.2 for cavity half parting line surfaces, and 200.2 for core half.

What surfaces go on the parting line level? Only and exactly the molding faces, excluding the part. Put another way, when the mold opens, you see part surfaces (100.1, 200.1) and other surfaces (100.2, 200.2).

Which plate(s) does XMD apply the surfaces to? Any plate the free surface intersects.  If it does not “enter into” the plate, it is not considered.  You can use the “identify plate surfaces” command to find out exactly (see below).

 Do I still need the free surfaces? It is still recommended that you start the job with the part surfaces (and parting line if available).  Other than that, once you have impressed the surfaces onto your solids, you should get rid of them to avoid duplication. 

What is the procedure for integrating the surfaces? There are many viable techniques.  One way is to create a trim sheet (start with the part and parting line surfaces stitched together and close up any free edges), and then trim your mold blocks against them using KeyCreator’s Trim Solid to Sheet Body/Faces command.  Another way is to import a solid from another CAD system.

A few things to keep in mind in terms of XMD:

  • Use the master plate (the one without holes) for surfacing and modeling operations.
  • Verify that after your surfacing, your plate is still a closed manifold solid.

Won’t XMD still need the part geometry? XMD has saved the size of the part in the .xmd file, and that is enough for most of our calculations.  This value can be verified in the parting line editor.

Can I trim my blocks AND keep free surfaces?

You can, but we don’t recommend it.  Keeping surfaced blocks and free surfaces creates more work for XMD, KeyCreator, and yourself!  XMD will use both the plate surfaces AND the surfaces on the part and parting line levels, meaning it will have twice as much data to process.  Duplicated geometry slows KeyCreator’s saving, loading, and basic rendering of the geometry.  It also means higher memory usage, which leads to a higher likely hood of instability.  And finally, YOU will have more work to do in order to keep both sets of surfaces up to date.  It will also be more difficult to anticipate what XMD will be looking at since it is pulling in geometry from multiple sources.

What if my components aren’t behaving, respecting the surfaces?

Usually this is caused by a problem with geometry.  To help diagnose the problem, use the “identify plate surfaces” command to see what XMD is working with. This command is a huge timesaver for getting to the bottom of such issues.  It may be that there is some geometry on the part/parting line levels you forgot about. If so, these levels will be turned on and the offending faces will be highlighted.

Upon running it, you are asked to choose from 4 surface sets to display:

  • SelPlt (Select Plate) – Identify the surfaces for a selected plate, as used by AutoWater, bubbler projections, and SmartWater’s AutoDepth mode.
  • CorHalf (Core Half) – Identify the core half parting surface as made up by a combination of core side plate solids.  Ejector pins use this set of surfaces.
  • CavHalf (Cavity Half) – Same as above but on the cavity side.  (Currently, no commands use this set of surfaces, but if you’re really curious…)
  • IntfChk (Interference Checking) – This set of surfaces represents what XMD feels are the critical faces of a particular plate solid.  By critical faces, we mean the faces that you really don’t want a drill bit busting through!  It is used by the new “Plate Faces” option in Interference Checking, except for waterlines.  Waterlines are checked against every plate face.

Once you’ve made your choice, XMD will then show you the desired surfaces.  Some examples are pictured below.

Core Half: this surface is made up of multiple plates. This is the set of faces ejector pins project to.

Select Plate: The computed surface of a single plate. These faces are used by bubbler projections and AutoWater.

Contact Us

We worked hard to get this working smoothly.  In the event that you are still having difficulties, please call.  Sending us a screenshot of those highlighted faces may be helpful. Whatever the problem is, we will go out of our way to get it corrected and fixed up for you.