×
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

Rubber Molding for Checking Thread Profiles

Rubber Molding for Checking Thread Profiles

Rubber Molding for Checking Thread Profiles

(OP)
In order to check thread profiles on our parts, we use a product called ReproRubber.  Its a two part mixture that when mixed and placed over the threads, it hardens and allows us to verify the profile.  This stuff is rather expensive and we are looking for alternative solutions.

I've found a few possible alternatives but I wanted to put this out there to see if anyone had some suggestions.

RE: Rubber Molding for Checking Thread Profiles

Not sure from your description how much heat is allowable but there are several low temp (120-200 DegreeF)compounds available through McMaster Carr.  They are listed under Cerro alloys.  They give good detail and are not too difficult to work with.
Another material that gunsmiths and mold makers used is sulfur.  They melted it, poured it in a gun barrel or mold.  It gave good detail with minimal shrink.  Worked well for internal threads with the addition of a tab for handling.

Griffy

RE: Rubber Molding for Checking Thread Profiles

It sounds to me like paraffin wax may also work.  Self-lubricating, low melting, reuseable. It may not have the rigidity necessary, but may be worth a shot.

aspearin1

RE: Rubber Molding for Checking Thread Profiles

Try a silicone or urethane rubber mold making material.  Be sure to use a mold release with the urethane or it might stick.

RE: Rubber Molding for Checking Thread Profiles

(OP)
griffengm,  the application is room temperature.  Its a room temperature cure, sets up in around 8 minutes and hardens to a rubber like consistency.  But I'll still look in Carr just to see.

RE: Rubber Molding for Checking Thread Profiles

jvisosky,
I used a similar material from Devcon for a time to make holding fixtures.  To reduce the amount actually needed, we used a rough core made of steel and cast the rubber around it.  This let us reduce the castable by 4-6 X.

Griffy

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