How to extract numbers for calculation when entering a string of text into a cell

Function calPP(inputStr As String) As Double
    Dim dimensions() As String
    dimensions = Split(inputStr, "*")
    If UBound(dimensions) < 2 Then
        MsgBox "Input format error, please make sure the input contains 3 numbers separated by '*'."
        B1 = 0
        Exit Function
    End If
    Dim od As Double, id As Double, ln As Double
    od = CDbl(Replace(dimensions(0), "mm", ""))
    id = CDbl(Replace(dimensions(1), "mm", ""))
    ln = CDbl(Replace(dimensions(2), "mm", ""))
    Dim volume As Double, mass As Double
    volume = (od - id) * ln * 8.96
    mass = volume / 1000
   calPP = mass
End Function

Why can't the code get results


Cell A1 Key in OD9.525*0.8mm*850mmL

formula like this ((9.525-0.8)*850*8.96)/1000

Cell B1 Get result is 66.4496