Do all bevel gears of the same MOD mesh?

[RainbowsParticipant @rainbows]

With one of these 15T 30T bevel gear pairs you can buy off ebay is it possible to buy two and mate the gears of the same size with each other to form a mitre?

I was reading up on miter gears and some stuff implied that the gears only worked in specific teeth pairs. Thought it best to check.

[RainbowsParticipant @rainbows]

[vintagengineerParticipant @vintagengineer]

If they are the same MOD they should mesh so should run together.

[jacques maurelParticipant @jacquesmaurel42310]

you must buy the gear pair as the angle between the gears axis is involved.

J Maurel

[JasonBModerator @jasonb]

As Jacques says you need the correct pairs, a set of 15/30 will mesh with each other but you could not mesh a gear from a 15/45 set with them even if the same Mod or DP.

Good by those gears I have used them on a model, could not buy one of the two cutters for that sort of money.

Edited By JasonB on 07/01/2017 07:44:22

[Anonymous]

Posted by Rainbows on 06/01/2017 23:20:38:

…….is it possible to buy two and mate the gears of the same size with each other to form a mitre?

In a word, no.

The two gears will mesh, as they're the same MOD, but the pitch cone angles will be wrong, so the axes will not intersect at right angles.

By definition mitre gears have a 1:1 ratio, ie, the same number of teeth. Consequently the pitch cone angle will be half the axis intersection angle. So if the gear axes intersect at 90º then the pitch cone angles need to be 45º. Like these 16 tooth gears that I have modelled in 3D CAD:

The tooth shape depends on both the number of teeth and the pitch cone angle, unlike spur gears.

Andrew

[Michael GilliganParticipant @michaelgilligan61133]

Posted by Andrew Johnston on 07/01/2017 08:38:42:

Posted by Rainbows on 06/01/2017 23:20:38:

…….is it possible to buy two and mate the gears of the same size with each other to form a mitre?

In a word, no.

The two gears will mesh, as they're the same MOD, but the pitch cone angles will be wrong, so the axes will not intersect at right angles.

.

That's a very clear summary, Andrew … Thanks.

MichaelG.

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