internal blind spline relief or cross hole spec for manufacture

[james_humphrey]

I need to spec the relief or cross hole required to allow manufacture of a blind spline.

if my understanding is correct, either I can have the spline cut with EDM in which case no relief is needed, or I go for broaching where a relief below the spline is needed to remove chips and allow the tool to pass.

As the shaft is critical structurally I need to be able to design the relief accurately for use in FEA software.

Can anyone point me toward a standard or similar to define the required relief for a given spline type.

(FYI - spline is a blind internal ANSI B92.1 class 5-44mm nominal diameter-13 teeth-8/16 pitch-42mm deep, shaft is 90mm OD where spline is required)

[Kelly_Bramble]

I don't think there is an industry specification that defines a manufacturing access relief for broaching or plunge EDM..

You can look at industry standard broaching tools to estimate clearance. Ultimately, each sourced manufacturer is going to different capabilities - a design for manufacturing review will get you the advice you need for the clearance details.

As the shaft is critical structurally I need to be able to design the relief accurately for use in FEA software.

That plan will drive the costs up - design for an adequate FOS if you have the material. Don't over tolerance..

[jboggs]

Talk directly to the shop that will make it. They will be the ones either cursing or praising "the engineer that came up with this" when they have to make the item to print!