Profile and lead traces

[[Lo...]]

Hello everyone,

I am having an issue with the profile traces on splines I am inspecting. They look horrible but the lead traces seem to look fine. Believe I ran into this before but can't remember how I remedied this. Included the gearing data and I am also using a 1mm probe. I am evaluating all 11 teeth not just 4. Not sure if that is something that needs to change or not. I am sure I left some details out that could help. Thanks for any assistance.

Lou

[[Ri...]]

1mm styli is too large for an internal spline of this size. You should either use a 0.3mm or 0.5mm given the available tooth length is only 0.05" (1.3mm). 

In addition, speed is also a factor - short splines require you to go much slower (especially on the involute/profile). 

[[Lo...]]

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Thanks Richard. Have a .5mm probe but ended up cutting the part down to get the probe to reach. And slowed the CMM down. Lines are a lot straighter than before, notice there is quite a bit of pitting or chipping on the splines as well. I'm sure thats not helping much. Thanks again.

 

Lou

[[Do...]]

Curious how you guys determine the scan path for your profiles. The method we've used measures from the True Involute Form to the OD low limit (for external gears) or the ID high limit (internal gears). 

[[Ri...]]

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 Usually you are limited to what the drawing stipulates. I've seen drawings have no specs on the involute form, and I've seen drawings have both the upper/lower limits of where the involute is to be valid. 

Sometimes it just isn't possible though due to the sizes required to achieve the spec limits, but I would always start by following what the drawing states. In most cases they just have the TIF, in those cases I just typically ensure that I am meeting that, and then let GearPro set the other limit. Obviously if there is a root/tip radius that I need to avoid I will adjust accordingly for that.