Contact US

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!

*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




Here is the hypothetical. We must drill a hole to mount a feed-thru terminal with a body diamter of .145 +/-.010. The feed-thru must be soldered in with a gap around the body of approximately .005 to ensure good capillary action to flow the solder. Taking into account tolerances, what size hole should be called out on the housing?

RE: Tolerance

Hi Billtati

Does the feedthru manufacture spec the proper hole to drill.  Most electrical components give you the required hole and mounting foot prints.

Having said this I would drill a 5/32" or .156.  This gives you the required .005 gap nominal, and in a worst case the feedthru still fits.


RE: Tolerance

Unfortunately the manufacturer (Tusonix) does not give a recommended mounting hole. Your answer makes sense but I think you understand my concern. If the feed-thru comes in on the high end (.155) and the hole in the housing is 5/32 (.156) the solder MAY not flow correctly. Thanks for the second opinion. I believe it is what I will do.

RE: Tolerance


You know there are mfgrs who make solder preform rings.  All you have to do is slide them over the solder terminal and heat them with a heat gun.  I believe RAYCHEM (now part of TYCO) is one mfgr.


RE: Tolerance

Yes. We are using preform rings. However, thanks for the heads-up!

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! Already a Member? Login


Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close