Open an new drawing and insert a U shaped Rebar; add a Mark and link it to the Rebar.
Edit the Mark and insert n=5. Leave a zero spacing and a zero range; we just want five pieces of this rebar. Generate the BBS and verify that it does show a total of 5 bars for the record number 1.
Make a copy of this Mark and double click it to edit n=3. When an AutoRebar object is copied, it inherits all the links of the original object. This means that the copied Mark is also linked to the same Rebar and vice versa (try to stretch the Rebar and you’ll notice both the Rebars to update).
Click to update the schedule; because these two Marks share the same Mark Number and are linked to the same Rebar, they add up to the same record in the bending schedule. The BBS now displays a total of 8 bars for the Mark Number 1.
Now copy the Mark again but this time change the Mark number from 1 to 2. Leave the n=3 field untouched and close the edit form.
Update the BBS. Although this new Mark is linked to the same Rebar, it creates a new record in the schedule because it has a different Mark Number.
Now insert a second Rebar, a simple straight bar (or any other shape you may prefer; I will refer to a straight bar for the sake of simplicity).
Select the newly created straight Rebar and click to add a new Mark linked to it; the new Mark Number is 3 because a Mark Number 2 is already present in the drawing. Leave the default n=1 field; we want this Mark to bring just a single instance of this straight bar.
Update the BBS. A new record is created for the Mark Number 3.
Now edit Mark 3 and change the Mark Number from 3 to 2. This action will generate a conflict and AutoRebar warns the user with the following Message when the BBS command is executed:
WARNING: a conflict of Mark numbers has been detected. Two Marks share the same position n.2 but they refer to different Rebars.
The duplicate Mark has been excluded from the Bending Schedule. Please resolve the conflict to complete the BBS.
Edit the Mark again to solve the conflict by changing the Mark Number; use 5 (or any other unused Mark Number).
Update the BBS. A new record is added for the straight bar under the new Mark Number.
By default AutoRebar starts the Mark Numbers from 1. This can be changed in
Options > Marks > Mark data > New Mark numbers start from n.
That can be useful to assign different Mark numbers to different parts of a structure. For instance, in a multi story building:
Mark numbers 100, 101, 102, ... for level 1;
Mark numbers 200, 201, 202, ... for level 2;
Mark numbers 300, 301, 302, ... for level 3;