Autodesk 00128-051462-9310 - AUTOCAD 2008 COMM UPG FRM 2005 DVD, User Manual

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Then… If you want to…
select Calculation rules, and then enter a value for Riser Count. specify the total number of stair risers
■
When Riser Count is set to (automatic), the number
of risers is based on the overall length and overall height
of the stair and the code limits specified on the Design
Rules tab. The Straight Length value of the stair is
adjusted automatically.
■ When Riser Count is (user-defined), you can specify
a value that is used to calculate the tread depth and riser
height. If these values fall outside the stair limits, an error
message is displayed.
select Calculation rules, set all fields to (automatic), click
the icon to Riser to change it to , and enter a value for
Riser.
specify the height of each riser in the stair flight
select Calculation rules, set all fields to (automatic), click
the icon next to Tread to change it to , and enter a value
for Tread. You can also specify the Riser count when you set
the tread depth.
specify the tread depth for each tread in the stair flight
NOTE If a value is set to user-defined on the Calculation rules worksheet, it can be modified directly in the
Properties palette.
NOTE If is displayed next to a field in the Calculation Rules dialog box, that field can’t be changed until
another field is changed from (user-defined) to (automatic).
9 Select the type of arc constraint to use when creating the spiral stair:
Then… If you want to…
select Free for Arc constraint. create a spiral stair run with no constraints
select Total Degrees for Arc constraint, and enter a value for
Arc angle. This includes the terminal landing or tread. create a spiral stair with a specific number of degrees for the
stair flight
select Degrees per Tread for Arc constraint, and enter a value
for Arc angle. create a spiral stair with a specific degree for each tread in
the stair
10 Expand Advanced.
11 Specify the Floor Settings:
Then… If you want to…
enter a value for Top offset. change the thickness of the floor finish material at the top of
the stair
enter a value for Top depth. change the depth of the structure at the top of the stair
enter a value for Bottom offset. change the thickness of the floor finish material at the bottom
of the stair
Creating a Spiral Stair with User-Specified Settings | 1151