CHS Handrail

posted 18 Feb 2013, 18:41 by Colin Manning   [ updated 26 Mar 2013, 06:45 ]
Create a CHS Handrail in seconds. For Bocad users in Australia, the PST Handrail has been the standard way for placing Monowills handrail. It does the job well, but there are some issues.

Some history

The original PST Handrail was modeled using square bar for the stanchions, rails and balls, and the balls and baseplates were placed as dummy members.

When PST wrote the original macro, Bocad was running on HP computers running HPUX, with a massive 64-128 MB of memory - Megabytes, not Gigabytes, and running at lightning fast 75MHz - again Mega, not Giga! The limited performance (by todays standards) of these computers required simplification of the model as much as possible, hence using solid square bar (One point for each end - two points in total) in lieu of a CHS (as much as 36 points at each end - 72 points). This provided a considerable reduction in the time to generate or refresh views, and the size of the model database.

Another simplification involves creating dummy balls and dummy baseplates. The dummy baseplates can lead to incorrect bolt location lists, as the bolt list may indicate that the beam is bolting to an unknown member, resulting in wasted time, mistakes and frabricator queries. The model is not complete and not directly manufacturable.

Our Solution

Based on the original PST macro, the modified macro places the stanchion and rails using the profiles documented by Monowills, and creates the stanchions as one member. This allows the selection of the stanchion as a member, not requiring the operator to remember to select the stanchion as a construction group or assembly, and the beam is bolted to the stanchion member, not the stanchion assembly.

We have also modified the dialogue box for PST ==> Handrail ==> General settings to allow for Shop vs Site run handrailing, and merged vs non-merged stanchions.

We have also modified the end closure macro to place either a top, bottom or horizontal end closure, naming it to comply with the current Monowills naming convention - less work when it comes to editing your drawings or lists.

In summary:
  • Use CHS instead of Solid Bar
  • No dummy members
  • Single part stanchion
  • Model represents actual build, rather than approximation
  • Option to select Shop vs Site run handrailing
Modified PST Handrail in action
Image: CHS Handrail

CHS Handrail