To Work with Bend Tables
Inventor can include an Excel bend table, use an external Excel bend table, or import a bend table in a .txt file.
Include an Excel Bend Table Using the Integrated Editor
A column for a specific bend radius must contain values for each specified angle row. Each cell within the table must contain a value.
On the ribbon, click Manage tab
Styles and Standards panel Styles Editor 
.In the Style and Standard Editor dialog box, click the expand/collapse “+” to the left of the Sheet Metal Unfold Rule.
In the list of existing unfold rules, click the Default rule to serve as a template.
At the top right of the Style and Standard Editor dialog box, click New.
In the New Style Name dialog box, name the new sheet metal unfold rule you are about to create. In Name, enter a descriptive name to replace the supplied Copy of Default, and then click OK.
In the new sheet metal unfold rule that is listed, enter the following edits:
- Method. Bend Table
- Linear unit. Set for the bend table
- Using Excel, open the bend table that you want to use.
- In Excel, select the range of cells containing the bend angle column and the row of bend radii and all cells for the selected angles and radii. Use CTRL+X, cut these cells to the clipboard.
- In the Style and Standard Editor dialog box, click to add a thickness value, and enter a value for thickness.
- A table consisting of rows and two columns appears to the right. Position your cursor in the empty cell in the upper left, right-click and then click Paste Table. After the cells in the integrated editor populate with the data that you cut from Excel, click within any cell to edit it.
- To add rows and columns, right-click a cell and then click Insert Row or Insert Column.
When you finish your edits to the bend table, click Save.
Set Up Externally Stored Bend Table Using Excel
Browse to the sample bend table spreadsheets in the \Autodesk\Inventor [version]\Design Data\Bend Tables folder (in \Documents and Settings\All Users\Application Data) and double-click one of the .xls files to open it.
Scroll to the line that starts with /U, and enter units of measure.
Scroll to the lines that starts with /T and enter the following tolerances:
- /T1 +/-. Represents the default sheet metal thickness specified in the Sheet Metal Styles dialog box.
- /T2. Determines if a bend radius parameter that is outside the range of bend radii values is valid. If the parameter falls between two bend radii, then the analyzer interpolates the correct value.
- /T3. Determines if a bend angle parameter that is outside the range of bend angle values is valid. If the parameter falls between two bend angles, then the analyzer interpolates the correct value.
Select File
Save As, give the spreadsheet a new name, and click OK.
Edit Externally Stored Bend Table Using Excel
You can use a bend table file that has your units of measure and tolerances to create a bend table for each material thickness.
When you edit the value of specific bend deductions, a conditional equation determines the bend deduction values provided in the sample spreadsheets. A bend table that is populated with empirical values determined by measuring sample pieces produced on a specific piece of equipment is more valuable.
You save the spreadsheet in a text (*.txt) file because the analyzer uses the text format to calculate bends.
- Browse to the bend table *.xls file, and double-click to open it.
- Scroll to the line that starts with /S and enter the sheet thickness, and then scroll to the line that starts with /R and enter bend radii.
- Edit the value of specific bend deductions, as required.
- Highlight and copy the table, then scroll down to an empty area of the spreadsheet and then paste the copied table.
- Rename the table and reset the material thickness.
- Continue to copy and paste the table, renaming it and setting a new material thickness, as necessary.
- Select File Save As, select .txt file type, and then click OK.
Import Bend Tables Previously Saved as *.txt
Releases before R2010 required that you edit and save bend tables as ASCII text files (*.txt). You can import and save these files as an unfold rule. The bend table that was previously saved as text is imported to the newly named style. You can make any additional edits using the integrated bend table editor.
- On the ribbon, click Manage tab Styles and Standards panel Styles Editor.
- On the lower left side of the dialog box, click Import.
- In the Import Style Definition dialog box, browse to the folder for your bend table text file.
- Set Files of type to: Bend Table Definition (*.txt)
- Select the file containing the bend table that you want to import.
- Click Open.
- In the New Style Name dialog box, enter a meaningful name.
Sheet Metal Bend Table Example
;
; Use an ASCII file editor to customize the values to your specific conditions. All bend radius columns must contain values.
;
;-----------------------------------------------------------------------
;
; Notations used in tables:
;
; ';' = remark character
;
; '*' = start of a new table
;
; '/' = special character
; U = units of tolerance; thickness; bend radius; and correction values
; m; cm; mm; micron; in; ft; or yd
; S = sheet thickness
; R = bending radii
; A = opening angle
; T1 = Tolerance (+/-) for sheet thickness S (valid for the whole file)
; T2 = tolerance for equal min and max bending radius R
; The T2 tolerance is used at the minimum and maximum
; bending radii R in the tables. For model bend radii that fall
; between two values existing in the table, the resultant
; correction value X is determined by linear interpolation
; using the appropriate x values in the table.
; T3 = tolerance for equal min and max opening angle A
; The T3 tolerance is used at the minimum and maximum
; opening angles A in the tables. For model opening angles
; that fall between two values existing in the table, the
; resulting correction value X is determined by linear
; interpolation using the appropriate X values in the table.
;
;-----------------------------------------------------------------------
;
; The correction value X is applied as follows:
;
; L = A + B - x
;
; (L = unfolded length in flat pattern)
; (A = length of side A (outside measurement of bending zone))
; (B = length of side B (outside measurement of bending zone))
;
;-----------------------------------------------------------------------
;
; Angle A expressed in degrees.
;
;-----------------------------------------------------------------------
;
;
;UNITS for tolerance; thickness; bend radius and correction values
/Ucm
;
;TOLERANCES valid for the whole file
;
/T10.000100
/T20.010000
/T30.010000
;
\*\*\* TABLE 1
;
;sheet thickness
/S0.050000
;