Winding springs

Around August 25 1995, there was a discussion on piano wire and music wire, and Mike Rehmus (mrehmus@grayfax.com) posted a Basic program to calculate parameters for winding springs from these types of wire. The program is from an article in the February/March 1991 issue of Strictly IC magazine. Mike reports that there were a few errors in the published version, and says that this program works and comes up with the same numbers as the examples in the article.

There were also some corrections described on page 23 of the April/May 1991 issue.

In addition, there was a 2-part article in Home Shop Machinist by Kozo Hiraoko, May/June and July/August 1987; this is reprinted in the book Projects 3, available from the publisher of HSM. This article uses nomographs to do the calculations and shows setups for winding springs using a lathe.

In making this program work on various systems (there is no practical standard for BASICs) there are a few things to be aware of.

• On some systems, PI is a reserved name for the constant 3.14159265... On others, you will have to add line 10 to define PI.
• On some systems, LPRINT will print to the line printer, but on others it is not a valid command. PRINT can be substituted.
• On many systems, MID is a reserved word (for extracting/inserting strings) and cannot be used for variable names. You can replace MID with some other variable such as MIDID.
• On some systems, using TAB(xx) in a print statement requires a semicolon (";") between it and the following variable.

• The BASIC program

In January 1998, Dave Silberstein ( bazillion@earthlink.net) put together some very nice web pages on understanding and making springs. See http://home.earthlink.net/~bazillion/springs.html.