Author Topic: Excel list - program for gears  (Read 29452 times)

Offline GeorgK

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Excel list - program for gears
« on: August 10, 2007, 02:41:25 PM »

I am straight at the beginning of my new hobby. Unfortunately I do not know very well how to make the gear wheels. Did someone already draw gear wheels, did some Excel calculations or has written a program with that is possible to produce gears?

I would like to get dxf-files for my cnc mill.
Thank you


Offline jss

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Re: Excel list - program for gears
« Reply #1 on: August 11, 2007, 09:31:58 AM »
You may want to look into a program like this.  I have no knowledge of its functionality, however it appears to offer at a modest price the features you want.

Involute and Cycloidal
Gear-Wheel GCode Generator

    *This design solution from Graham Baxter easily designs the tooth form.
    * Handles BOTH internal and external spur gear designs.
    * No need to create gears in CAD then export to a GCode Generator. Saves time!
    * Creates a tool path file for a CNC mill.
    * Makes a DXF file for verification.
    * Output is in standard GCode format and without modification is read by standard viewers.
    * priced at only US $49.00.

Offline GeorgK

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Re: Excel list - program for gears
« Reply #2 on: August 14, 2007, 10:05:40 AM »
Thank you very much for your answer.  I am looking for a program where I can see the parameters.



Offline bobledoux

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Re: Excel list - program for gears
« Reply #3 on: August 15, 2007, 06:22:39 AM »
Try this.  Build a spreadsheet with the factors:

Offline Martyb

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Re: Excel list - program for gears
« Reply #4 on: August 15, 2007, 07:43:16 AM »
I've combined the clock math spreadsheet from Gary's wooden clocks
With that module calculations sheet (Posted originally by JR I believe)
For me that give a nice single point of reference for a large part of the calculations in gear train.

I also have that gear generator listed.  If you build the spreadsheet like we're talking about, you can take the module it calculates and punch it into the gear generator.  The generator will then recompute the other variables and you can compare.  The combination of all the tools has really helped my understanding of what people are talking about.  For the longest time, all the different diameter measurements was stumping me.  And yes, it gives me a shortcut to the gear profiles without drawing the tooth profiles independently.  I've pulled the generated DXF file into autocad to draw out the internal spoke designs.

There's another gear calculator spreadsheet floating around here as well.  I've got it marked as  It will generate the G-code for cutting the gears.  I haven't tried it out yet, since I don't have my CNC finished yet.

Offline jss

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Re: Excel list - program for gears
« Reply #5 on: August 15, 2007, 05:37:50 PM »
Two different offerings regarding you question.  I'm not sure these will fill the request.
download the trial and look at section 6 ,7 and 19 will draw gears with dxf-output --lastest ver is 1.15

MITCalc - Spur Gear Calculation v1.14 Shareware Download ...
Geometric design and strength check of spur gear (straight and helical) ... MITCalc - Spur Gear Calculation. License Type: Shareware. Date Added: July 29, ... - 17k - Cached - Similar pages

Geometric design and strength check of spur gear with straight and helical toothing. Application is developed in MS
Excel, is multi-language and supports Imperial and Metric units and solves the following main tasks:
- Calculation of helical and straight toothing (external).
- Automatic design of a transmission with the minimum number of input requirements.
- Design for entered coefficients of safety (static, dynamic).
- Calculation of complete geometric parameters (including corrected toothing).
- Optimization of toothing by use of proper correction (balancing specific slips, miminizing specific slips, strength...).
- Calculation of strength parameters, safety check.
- Design of gearing for exact axis distance.
- Supplementary calculations (calculation of parameters of the existing gear, temperature rise, design of shafts,
check dimensions).
- Support of 2D and 3D CAD systems.
- Drawings of an accurate tooth shape including data (X,Y coordinates).
- Support of 2D CAD (AutoCAD, AutoCAD LT, IntelliCAD, Ashlar Graphite, TurboCAD) and 3D CAD in full
calculation package (Autodesk Inventor, SolidWorks, SolidEdge, Pro/E). The calculations use procedures,
algorithms and data from
standards ANSI, ISO, DIN, BS and specialized literature. Used standards: ISO 6336, ISO 1328, DIN 3990, ANSI
B6.1-1968, AGMA 2001-C95, AGMA 2001-D04, AGMA 908-B89/95 and others.This module is a part of MITCalc -
Mechanical and Technical Calculation Package for gear, belt and chain drives, springs, beam, shaft, bolt
connection, shaft connection, tolerances and many others

 6.1   Number of teeth Pinion / Gear                                                     N           21              38
 6.2   Face width (Pinion / Gear)                                                        F        5.6000           5.4300           [in]
 6.3   Normal module                                                                   mn                 0.3333                    [in]
 6.4   Transverse module                                                                mt                0.3333                    [in]
 6.5   Diametral Pitch (normal)                                                         Pn                3.0000
 6.6   Diametral Pitch (transverse)                                                      Pt               3.0000
 6.7   Circular pitch                                                                   pn                1.0472                    [in]
 6.8   Transverse circular pitch                                                         pt               1.0472                    [in]
 6.9   Base circular pitch                                                              pN                0.9840                    [in]
6.10   Base circular pitch transverse                                                   pT                0.9840                    [in]
6.11   Center distance (pitch)                                                           C                9.8333                    [in]
6.12   Center distance (production)                                                    Cm                 9.8333                    [in]
6.13   Center distance (working)                                                       Cw                 9.8333                    [in]
6.14   Pressure angle                                                                   F                 20.0000                   [°]
6.15   Transverse pressure angle                                                          t               20.0000                   [°]
6.16   Pressure angle at the pitch cylinder                                          F wn                 20.0000                   [°]
6.17   Transverse pressure angle at the pitch cylinder                               F  wt                20.0000                   [°]
6.18   Helix angle                                                                       Y                0.0000                    [°]
6.19   Base helix angle                                                                Y b                0.0000                    [°]
6.20   Tip diameter                                                                    DO         7.6667          13.3333           [in]
6.21   Reference diameter                                                                D        7.0000          12.6667           [in]

  6.22   Base diameter                                                                    DB        6.5778          11.9028           [in]
  6.23   Root diameter                                                                    DR        6.1667          11.8333           [in]
  6.24   Operating pitch diameter                                                        DW         7.0000          12.6667           [in]
  6.25   Addendum                                                                         ha        0.3333           0.3333           [in]
  6.26   Dedendum                                                                          hf       0.4167           0.4167           [in]
  6.27   Tooth thickness on the tip diameter                                             tno        0.2336           0.2523           [in]
  6.28   Tooth thickness on the tip diameter (transverse)                                 tto       0.2336           0.2523           [in]
  6.29   Tooth thickness on the pitch diameter                                           tnc        0.5236           0.5236           [in]
  6.30   Tooth thickness on the pitch diameter (transverse)                               ttc       0.5236           0.5236           [in]
  6.31   Tooth thickness on the root diameter                                              tr       0.5532           0.6655           [in]
  6.32   Unit tooth thickness on the tip diameter                                        to*        0.7007           0.7569           [modul (1/P)]
  6.33   Unit correction                                                                  dY                0.0000                    [in]
  6.34   Total unit correction                                                        x1+x2                 0.0000                    [modul (1/P)]
  6.35   Addendum modification coefficient                                                  x       0.0000           0.0000           [in]


the following is a PDF---free

Using Spreadsheets to Parameterize Spur Gear Design for Laser ...
File Format: PDF/Adobe Acrobat - View as HTML
While many programs. exist to model non-linear surfaces, they do not work easily on the unusual design of a gear’s. tooth. Since spur gears are such a ...

Enjoy the reading!!

« Last Edit: August 15, 2007, 07:26:15 PM by jss »

Offline GeorgK

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Re: Excel list - program for gears
« Reply #6 on: August 16, 2007, 01:38:47 PM »
You can found the latest Excel version (GearCreate8) here: