×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

general question on splines

general question on splines

general question on splines

(OP)
How do I determine what spline is on an existing shaft? Is there a tool to measure the spline or a standard method of measurement. Does anyone have a resource for finding standard spline dimensions? Thankks in advance.

RE: general question on splines

Knowing the od and the number of teeth, you can use the
general equation.  OD = (N+.8)/DP   (DP =Diametral Pitch)

Splines are similar to 1/2 of a stub system as to Addendums
and Dedendums.  Metric

So the equation can be revised to
OD x DP = N +.8 and then
DP = (N +.8)/OD

This assumes no profile shift correction.

RE: general question on splines

dimjim

You forgot the pressure angle

RE: general question on splines

Israelkk,
I do not understand why pressure angle would influence the
od of a spline.  Wouldn't the od simply be pd plus two
addendums?  Were you confusing this with dimensions over pins or balls?

RE: general question on splines

Israelkk,
It just came to me what you were inferring.
Yes the equation would give you the DP of the spline,
but you would have to check the pressure angle by
using dimensions over pins and then probably require
two different ball sizes.  I am so used to working with
30 degree involute splines, I often forget there are
other standards as well.  Thanks.

RE: general question on splines

(OP)
Well, the most difficult thing about this shaft is the size of the splines, they are very small. It is a motorcycle shifter shaft if that helps. I'm trying to determine the size for a female mating end.

RE: general question on splines

Rob1970,
Small is relative.  What is the od and number of teeth.
Can you tell if the external spline has a straight or
curved surface?  There are Metric Splines as well.
Do you think the mortorcyle was made domestically or
abroad?  Internal Splines are kind of like the reverse
image of an external spline.  The tooth space must
exceed the tooth thickness of the external spline
by on a few 10 thousandths or 10 hundreths depending on
size.  What happened to the old part?  Totally destroyed?
It might be a standard SAE type spline if made domestically.  If so, then the information would be available in one of the SAE books governing Splines.










RE: general question on splines

First we need to know, if it is an involute pline. There are also standardised splines with triangular shaped teeth and also splines with teeth created with parallel straight lines.

RE: general question on splines

There are also metric involute splines which have addendum shifted teeth as standard.

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources