×
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

Best compound to join tube and insert

Best compound to join tube and insert

Best compound to join tube and insert

(OP)
I have a tube with a 0.300" hole through the center.  I need a compound that will allow a user to assemble an insert into the tube via a slip fit, but when cured will not come apart.  I have tired various loctite compounds (272, sleeve retian compound), but the inserts come loose during usage.  The compound will not see any shear forces due to axial loading of the tube, but will see heat (max 270F), vibration, and some twisting force (amount unkown, but not high).  

Dan

RE: Best compound to join tube and insert

What materials are you currently using, and what is the surface finish of the ID of your tube and insertion part?

What was the failure of the Loctite material?

Ray Reynolds
"Computers in the future may weigh no more than 1.5 tons."
Popular Mechanics, forecasting the relentless march of science, 1949
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?

RE: Best compound to join tube and insert

(OP)
The two parts are 4130 steel.  The surface finish is as machined, Ra ~ 15 uin.  The Loctite to this point seems to breakdown.  There are still remnants of the Loctite, but the two pieces are free.

RE: Best compound to join tube and insert

The cause of failure could be anything, from improper cure times, too much clearance between your parts, or simply the wrong Loctite product specified.  I don't think Loctite 272 is going to work in your application based on what you have provided.  272 is only a threadlocking compound, not really intented for the application you are using it in.

You might want to investigate Loctite 648, good for temperatures up to 300°F. Fills gaps up to 0.006" diameter clearance. Fixtures in 5 minutes.

Do some research on www.loctite.com if you are set on using their products.

Ray Reynolds
"Computers in the future may weigh no more than 1.5 tons."
Popular Mechanics, forecasting the relentless march of science, 1949
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?

RE: Best compound to join tube and insert

(OP)
I am not set on using Loctite.  Is there an industrial adhesive out there (two part epoxy??) that may do better than the products that Loctite produces?  Thanks for the help so far.

Dan

RE: Best compound to join tube and insert

(OP)
Thanks for all the help.  I am contacting all the vendors to get test samples of their best adhesive system.

RE: Best compound to join tube and insert

Duc916,
Is there a reason that this must be an epoxy?  Is solder or braze an option?

Griffy

RE: Best compound to join tube and insert

(OP)
griffengm ,
    I am mainly looking for a procedure that can be done in a few minutes on a bench top.  The reason I have stayed away from solder and brazing is the time and equipment needed to do this.  It is my understanding it would take an oven of some sort to heat the parts and braze the parts together   (furnace braze?).  I need a procedure that will allow the user to find the correct insert and assemble the parts relatively quick.

RE: Best compound to join tube and insert

Hi duc916

Have you considered a press fit instead of bonding, coefficient of linear expansion would be the same for both parts therefore no loosing with temperature. However without knowing any of the forces the components see in service it would appear to be difficult to reccomend either an adhesive or an actual imterference without testing them.


regards desertfox

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