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


Bushing installation with sealant.

Bushing installation with sealant.

Bushing installation with sealant.

I would like to install bushing with sealant per BAC 5435 which requires sealant having a continuous line (squeeze-out). Fairing-out of the squeeze-out is optional.I would like to know what is the definition of “Fairing-out”. Does it means to make to make squeeze-out more smoothly by tool.

RE: Bushing installation with sealant.

If I had a copy of it I could be certain, but I think it means that you should remove any sealant that will interfere with the fasteners you are going to install through the bushing later. Sealants often "squeeze out" of the joint when assembled, and one must always consider how that last step will be dealt with - either to wipe it off, or let the blob protrude. Some manuals go so far as to specify the shape of fillet that is acceptable. In your case, the sealant that squeezes out may cover he face of the bushing or fitting, preventing the fastener (or mating part) to rest flat.


RE: Bushing installation with sealant.

The most common reason for installing bushings with sealant is to prevent moisture from getting between the bushing and mating bore/face surfaces, where it can cause corrosion. If there are any tiny gaps between the mating surfaces left unsealed, any moisture present will readily be drawn into these voids. Checking that there is a continuous line of "squeeze-out" at the joint ends is an easy way to visually confirm it is properly sealed. Personally, I prefer fairing-out of any excess sealant wherever possible. It is usually quick and easy to do by hand, and looks way more professional. Also, for situations that are sensitive to debris, globs of excess sealant squeeze-out can eventually break loose.

RE: Bushing installation with sealant.

To add to tbuelna's comments...

The ring of sealant between the ends of the bushing and the surfaces surrounding the hole not-only verifies the integrity of the wet-seal installation [100% moisture resistant], it also minimizes the effect of electrolyte [moisture] bridging across the metal surfaces [which are usually dissimilar]... by tiny droplets or thin-films that may form.

Regards, Wil Taylor

o Trust - But Verify!
o We believe to be true what we prefer to be true. [Unknown]
o For those who believe, no proof is required; for those who cannot believe, no proof is possible. [variation,Stuart Chase]
o Unfortunately, in science what You 'believe' is irrelevant. ["Orion", Homebuiltairplanes.com forum]

RE: Bushing installation with sealant.

Thanks for the suggestions!

So the point is that I have to make sure there are no any gaps between bushing and housing to avoid corrosion.

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!


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