Recent content by gearguru

A lot of info here. When I worked with metric gears, I used metric units for all calculations; one can easily convert the dimensions to inches when its done and if it is needed. The Swedish designers did the same, I believe. Happy Easter to those who celebrate it.

Today is another anniversary - the Challenger... But let's go back to the OP: There are 4 books by Boris Chertok about the history of the Soviet rocket industry, available as a free download. Amazing and mostly very honest and very detailed writing by a person who was inside of it all...

If the "backlash" means "clearance" between two gears in mesh, then we need to know the meshing gear data (tooth thickness); or am I wrong?

tbuelna: As I put it before: the 18T/26T/70T configuration will not assemble with 3 equally spaced planets.

If the planets in the planetary with 18T sun, 26T planet, 70T annulus have to be equally spaced, then there can be just 2 or 4 of them.

Per my calculation no. of teeth on the mating gear should be 64: Center distance then will be 0.8*(11+64)/2 = 30mm (= 1.1811") To create the mating gear more data is needed: pressure angle, tooth thickness, outside dia, root dia...

Couple clicks and google found https://amesweb.info/Screws/metric-thread-dimensions-calculator.aspx Be aware: because of the tolerances, the actual dia of the external thread is always smaller than the nominal ( for example the M25 thread has the OD slightly less than 25mm; it allows to safely...

3DDave is referring to pitch, not to the OD of the (external) thread. His answer is correct for any metric thread with the 1mm pitch.

And one more: http://www.hessmer.org/gears/InvoluteSpurGearBuilder.html

This one looks interesting too. http://www.me-bac.com/index.php?task=gear

Lately I found several web pages for designing the gears. One of them is https://www.emachineshop.com/gear-design-software/ I did not check for accuracy of their calculations, use it carefully. I think that eventually we could create a list of similar services/apps with our own notes about them.

I do not remember that; did you try to look around using the "search" option on this page? What exactly are you looking for? I collected some calculations/standards/books/magazine articles; I might have what you need. Keep safe and healthy, fellow engineers!

@mfgeggear: I sent an email to the owner of the geargenerator, I believe he is in Hungary. Obviously he is a very skilled programmer. My calculations are mostly done in a spreadsheet, but in the past I also tried to create some simple programs in VB. They still work. Now I am retired and only...

I played with the geargenerator again. There is the option to create the internal gears as well. (in gear properties click on the box "internal". I was wrong in my previous entry. Very clever program. Now I'll check if I can enter my own major and minor diameters...

Well, mfgenggear is a very reliable source and "old" and knowledgeable member of this site too. Actually everybody in this thread brought interesting and valuable input. @mfgenggear : Thanks for the interesting links. The geargenerator web is nicely done, but does not allow to enter the tooth...