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Parametric Spur-Gear CAD file?
- Thread starter Helepolis
- Start date
mfgenggear
Aerospace
Please provide , hp or torque, RPM, diametral pitch or mod, pressure angle.
Have you calculated ? And trying to draw it?
AGMA van provide all the calculations.
There are free programs on line that can draw the geometry. For spur gears.
I have a program that can also draw it.
It cand create a ACAD file.
How will your gear be fabricated? For most gears, a machinist fabricates a blank, then they select an appropriate hobbing tool to cut the teeth. Your drawing calls up the number of teeth, the module for diametrical pitch and the pressure angle. Your CAD model only matters if you are 3D printing, or casting, or using powder metal.
Old drafting books have instructions on how to drawing good looking gear teeth using a compass. I have modelled gear teeth that way and 3D printed them. At modules of 1, or 1.5, they run smoothly. Performance-wise, the procedure approximates the involute form. Since I control the model, I added 0.1mm clearance around the teeth.
Look for an old drafting book, or Dudley's Gear Handbook.
mfgenggear
Aerospace
Drawoh
The issue is undercutting, the under cut will be above the true involute form diameter.
It will cause interference with the mating gear.
Profile shift will enlarge the pinion . It will require
A hob or cutter with the correct D÷F, depth of cut
To obtain the proper tooth thickness, and root.
And prevent interference. It's all spelled out
In agma.
Last edited:
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