Author Topic: Gear calculation help please  (Read 3355 times)

Offline Chuck in E. TN

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Gear calculation help please
« on: September 12, 2013, 03:10:27 PM »
 I am making a custom fine feed banjo for my 7x14 lathe. I have 20 and 80 tooth gears, from a laser printer, that are the same mod as the 7x change gears that I want to use.
 Is there a formula to calculate the center to center distance of meshed spur gears? I would like to lay out the holes for the gear axels without having to allow for adjustment for tooth mesh, making the attachment of the banjo via a clamp on the lead screw bushing.
 Chuck
« Last Edit: September 12, 2013, 05:44:47 PM by dsquire »
Chuck in E. TN
Famous TN last words: "Hey ya'll, watch this..."
MicroMark 7x14, HF X2 mill, Green 4x6 saw. Harbor Freight 170A mig

Offline tom osselton

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Re: Gear calculation help please
« Reply #1 on: September 12, 2013, 04:47:52 PM »
I would mesh them together and measure the inside of the shaft's then add 1/2  of both shaft's diameter should give the center to center distance.

Offline Pete.

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Re: Gear calculation help please
« Reply #2 on: September 12, 2013, 05:40:23 PM »
If you know the pitch circle diameter of your two gears the centers will be half the sum of their PCD's, plus whatever you allow for clearance.

Offline John Stevenson

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Re: Gear calculation help please
« Reply #3 on: September 12, 2013, 06:40:45 PM »
Chuck.
50mm answered over on HSM.
John Stevenson

Offline Chuck in E. TN

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Re: Gear calculation help please
« Reply #4 on: September 12, 2013, 07:23:05 PM »
John, I often post the same question to several forums. I get way more info, most of it good. Got 3 good websites and 1 good shop calculator program, all of which reinforced what I knew and what others provided.
Habit I guess, as I have friends all over the internet and no one close that shares the same interests.
I gratefully thank all that relied.
Chuck
Chuck in E. TN
Famous TN last words: "Hey ya'll, watch this..."
MicroMark 7x14, HF X2 mill, Green 4x6 saw. Harbor Freight 170A mig