WFret by Jonathan D. Whitney v1.01 Copyright (C) 2000
Support e-mail: WFret_sup@hotmail.com

Installation Instructions
=========================
1) Unzip WFret.zip to a temporary folder
2) Run the setup.exe that was extracted from WFret.zip
3) Follow instructions in the setup wizard
4) After installation is complete, you may delete the temporary folder at your discretion

Introduction
============

WFret is a program designed to meet the needs of luthiers who build fretted instruments.  It is a general purpose fret spacing calculator that also has the capability of printing a template which may be cut out and taped or glued to the fretboard blank to mark it for fret slotting.  This relieves the luthier of the painstaking chore of measuring the fret positions.  In addition, WFret will display and print a chart of the fret spacing measurements.  These can be represented in millimeters or in inches, with selectable precision of 0.5 or 0.1 millimeters or 1/64th or 0.01 inches.

On the subject of precision, WFret uses double precision floating point arithmetic to calculate the fret positions.  This is as accurate as possible given current technology.  In other words, fret positions are calculated to about 14 decimal places.  The selectable precisions round off the actual value to a measurement convenient to humans.  These rounded off values are displayed on the charts.  When a template is printed, the printing functions use the original (non-rounded) values to position the print head.  Thus the accuracy of the template depends on the accuracy of your individual printer.  I would suggest (beg, plead, and implore) you double check the template accuracy through another means (such as an accurate ruler) before cutting any slots.  This will also ensure that you have aligned the template accurately on your fretboard blank.

Main Screen
===========

Number of Frets: Type the number of frets you wish to display in the chart and on the template into this box.  There is no practical limit on the number of frets.

Scale Length: You can either type in a scale length or choose one from a drop down list of the more popular standard scale lengths. I've included on this list the scale lengths taken from several fret marking rulers, templates, and pre-slotted fretboards available commercially.

Verify:  This button simply pops up a window that displays the number of frets and the scale length you entered.  This may be used to see the scale length in different units - for example if you chose a scale length from the list (which are all in inches) and you want to see what it is in millimeters before printing the chart.

Display Chart: This button causes the fret spacing to be calculated and a chart displayed in the large text box at the bottom of the screen.

Print Template:  If you click here, WFret will print a fret slot cutting template on your printer.  You can cut this template out, tape or glue it to your fretboard blank, and use it to position your fretting saw for cutting the slots.

Print Chart:  This prints the same chart as the "Display Chart" button, but on your printer instead of the screen.

Exit:  Hey, I know - this button gets you out of WFret, right?

Measure Units:  By clicking on the Millimeters radio button, you select millimeters. That means the scale length you entered will be considered to be in millimeters.  But if you picked a scale length from the drop down list, it will be converted from inches to millimeters automatically.  If you prefer English units (which not even the English prefer anymore) you should select the "Inches" radio button.

Precision:  The radio buttons available depend on the type of measurment units selected.  For metric units, the precision is half millimeter and tenth millimeter.  For English units, the precisions are 1/64th inch and 1/100th inch.  These precisions apply to the chart functions, but not to the template function.  The templates are printed out as precisely as possible within the limitations of your individual printer.  Most printers such as ink jet, laser, or even the old 24-pin dot matrix printers, have a resolution of at least 300 dots per inch, and so they are plenty accurate.  However, it is wise to at least spot check the measurements with an accurate ruler before cutting into that $30 ebony fretboard blank.

Calculation Method:  These radio buttons let you choose between two basic methods of calculating the fret spacing.  The first method is a non-cumulative method.  The measurement of the fret distance from the nut is based solely on the scale length and the fret number.  These two variables are fed into a formula which is based on the fact that to raise the pitch of a string by a factor of 2 to the n/12th power, you shorten the string by that factor.  Musically, raising the pitch by 2 to the 1/12th power is the same as raising it one-half a step (for example, G to G-sharp, or E to F).  Raising it by 2 to the 2/12th (1/6th) power will raise it a whole step (G to A or E to F#), and so forth.  Therefore raising it by 2 to the 12/12th power (i.e. 2 to the 1st power or just plain 2) raises it one whole octave which is shortening the string by a factor of two - that is, dividing the length in half.

The second calculation method is cumulative, that is to say the results of each calculation are based on the results of the previous calculation.  The measurement from the nut to each fret is calculated by adding up the measurements from each fret to the preceding fret, all the way back to the nut.  Each measurement is calculated by a formula based on the rule of 18ths, which is that the distance to the next fret is 1/18th of the remaining vibrating length of the string.  However, the number 1/18 is not really very accurate - the better number is 1/17.817.  Regardless of which factor is used, an inherent problem with this cumulative method is that any error (such as rounding errors) will also accumulate.  However, rounding errors are minimized by the accuracy of double precision floating point arithmetic.  

The bottom line is this: for all practical purposes, it doesn't really matter which method is used.  The results will probably be identical within 1/10th of a millimeter for any normal scale length.  I've included both methods just for comparison purposes.  What does matter, is the factor you choose if you decide to use the rule of 1/18th method.  See "Preferences Menu - Calculation Method" below for more information.

Menus
=====

File Menu:  The file menu has selections for Retrieving and Saving fretboard configurations, for Printing charts and templates, and for Exiting the program.

- Retrieve fretboard configuration. This menu item allows you to retrieve a previously saved fretboard configuration.  A configuration consists of the number of frets, scale length, the measurement units (millimeters or inches), and the measurement precision.  The separate configurations are retrieved as a group, by a name (for example "Classical guitar").

- Save fretboard configuration.  This item allows you to save the current configuration with a name.  The name may be picked from a list of current names or you may enter a new name.

- Print. If you click on the print option, a submenu will pop out which will allow you to print the screen ("Quick Form Print"), print the fret spacing chart ("Chart"), or print a template ("Template").  The latter two are the same as clicking on the "Print Chart" or "Print Template" buttons.

- Exit.  Clicking on this item will get you out of WFret.

Preferences Menu:  This will let you choose the measurement system and precision, set printing options for templates and charts, and save and retrieve these preferences.  

- Millimeters.  Click on this item to use the metric system.  This is the same as the corresponding radio button.

- Inches.  Click on this to use the English system.  Same as the radio button.

- Half (Metric) or 1/64th (English). This corresponds to the similar radio button and selects the "coarser" measurement precision.

- Tenth (Metric) or 1/100th (English).  This selects the "finer" measurement precision, same as the radio button.

- Set Print Options:  This selection brings up the "Set Printer Options" dialog, which will be explained in detail later.

- Calculation Method: You can select either the non-cumulative method based on the "12th root of 2" formula, or the cumulative method based on the "rule of 18ths."  To select the non-cumulative method, click on "Non-cumulative (12th root of 2)" on the Calculation Method pop-out menu.  To select the cumulative method, click on one of the three factors to be used in the calculations, as explained below:

--Common.  This factor is 1/17.817 (or, the inverse is 0.0561256).  This is the factor most often published.  I believe it to be the correct factor to use, because it yields a position for the twelfth fret (the fret one octave above the open string) which is exactly one half the non-compensated scale length.

--Sloane.  This factor is 1/17.835 (inverse 0.0560695) Respected luthier and author Irving Sloane published this factor in his book "Making Musical Instruments."  I have been unable to determine whether this is simply erroneous or whether it was an attempt to compensate for the string stretching as it is fretted, as this factor yields a slightly longer vibrating portion of the string.  However, this type of compensation is usually done at the bridge, not in the fretboard.

--Primitive.  This factor is 1/18 (inverse 0.0555555)  The method of calculating fret positions used to be known as the rule of eighteenths. This factor was used because it was easier to figure than the more accurate common factor, at least in the days before calculators. I included this choice in case you are reconstructing an earlier instrument that you know used this calculation factor.  I wouldn't recommend it for a new instrument.

--Explain.  This will give you a rehash of the information above.

Back to the Prefences menu,

- Save Current Preferences as default.  By clicking on this option, you will cause the program to save the current calculation factor and print options as the defaults which will be in place each time you run WFret.  Caution: once you save the preferences, there is no automatic way to revert to previous preferences.

- Reload Preferences from Defaults.  If you have made changes to the preferences but HAVE NOT SAVED them, and wish to revert to the defaults, you can do so by clicking this option.

Help Menu:  There is no Windows Help file currently implemented for WFret.  However, useful information is contained in this Read Me file.

- View ReadMe file.  Click here to view this file.  Click Okay when done, or Print to print this file.

- About...  This will display a small blurb about this program, its version, author, etc.

Set Printer Options Dialog
==========================

A message area at the bottom of the Set Printer Options Dialog provides help when running this part of the program.  

Fret Slot Cutting Template Print Options: 

Vertical (fret postion marker) line width (pixels). You can enter the number of pixels (dots) for the width (thickness) of the lines used to mark the fret positions on the template, in this box.  The thinner the line, the better, as long as you can see it.

Vertical Line Length.  This box allows you to enter a number which is the length of the vertical fret markers.  This is converted to millimeters if the "Inches" radio button on the main window is selected.  It is displayed back in millimeters when you are done typing.  The vertical line length corresponds to the width of the fretboard blank.  You may prefer a short line length (for example, to make tick marks at the fret positions along the edge of the fretboard blank) or a longer one so as to cover the entire fretboard blank with the template.

Space between template lines. You can enter the distance between the lines (rows) of the template printout here.  Like the Vertical line length, if you are entering in Inches, this value will be converted and displayed in millimeters.

Horizontal (alignment guide) line width (pixels). In this box, you can enter the number of pixels (dots) for the horizontal line which is used as the alignment guide.  This line is used to align the template to the fretboard blank.

Alignment guide position. This box contains three radio buttons for selecting whether you want the alignment guide line to be printed at the top, center, or bottom of the template.

Print Fret Numbers.  Check this box if you want the fret numbers to be printed on the template adjacent to the fret position markers.

Fret Spacing Chart Print Options:

Chart Font Size.  You can enter a number in this box which will be used as the font size for printing the fret spacing chart.

Using The Templates
===================

First, before printing the templates, determine the horizontal alignment guide line position: top, center, or bottom.  This will relate to your fret slot cutting equipment.  The center alignment line should be useful for slotting fretboards that are profiled before slotting such that the sides are tapered and thus cannot be used for alignment purposes.

After printing the templates, cut carefully across the paper along the horizontal lines, leaving the side margins of the paper (which are the end margins of the template strips) intact.  A paper cutter will be helpful for this purpose.  Next, using double-sided tape or glue, fasten the first (nut end) template strip to the fretboard, carefully aligning the horizontal alignment guide along the length of the fretboard and the first vertical mark with the end of the fretboard if already cut square, or else the position where the fretboard will be cut off for the nut.  If you prefer using a "zero" fret on your instruments, the first vertical mark should be placed in that position. The next strip should be fastened on overlapping the previous one, with the first fret marker exactly on top of the last fret marker of the previous strip (these two fret markers correspond to the same fret position).  Cutting the end of this strip diagonally may help in aligning these two marks.  Be sure that the horizontal (lengthwise) guidelines remain exactly in line also.  Continue with the remaining strip(s).  Prior to cutting the fret slots, check the measurements with an accurate ruler - check at least one fret position for each piece of the template.  Also, unless the fretboard sides are already tapered, check with a square that the fret markers are perfectly perpendicular to the edge of the fretboard which will be rested against the fret saw guide equipment (miter box or miter gauge, for example).  Remember, measure twice, cut once.

The accuracy of the template depends a great deal upon your printer.  I suggest that the first time you use WFret to print a template, you check the template accuracy thoroughly to ensure that it will meet your needs.


Support
=======
This software has been freely donated to the fretted instrument building community. My personal interest in supporting this program is high, but since I am not charging for this software my legal and moral obligation to support it is non-existent.  That said, I will make an earnest attempt to provide whatever support is needed.  I have set up an e-mail account specifically for support matters.  The address is WFret_sup@hotmail.com.  I will endeavor to check this account regularly for any support questions and respond to them.  Please direct all correspondence to this account.

Change History
==============
V0.90  Initial version
V1.00  Added 12th root of 2 calculation method.  Fixed rounding problems for .01 inch and
       0.1 mm chart display and printout.
v1.01  Fixed Print Preferences.  Fixed preferences menu selection of coarse measure
       resolution