Bonding aluminum to aluminum - Doable? How?


Page 1 of 2 12 LastLast
Results 1 to 12 of 17

Thread: Bonding aluminum to aluminum - Doable? How?

  1. #1
    Registered
    Join Date
    Apr 2005
    Location
    Brazil
    Posts
    101
    Downloads
    0
    Uploads
    0

    Default Bonding aluminum to aluminum - Doable? How?

    Dear expert machinists:

    Here is the problem: I have a lot of aluminum extrusions, but they are all a little thin: 1/8".
    Now, when I need a thicker piece, I was wondering if I could bond together a few thinner
    pieces, with some type of adhesive, and end up with a material "almost as rigid" as
    the real thing: say, three 2"x1/8" bars to make a 2"x3/8" bar.

    Is this doable? What kind of adhesive would strongly bond aluminun to aluminum?
    Epoxi? How to prepare the surfaces and conduct the cure?

    Thanks a lot for your suggestions

    Nelson

    Similar Threads:
    Last edited by Arquibaldo; 10-29-2009 at 02:52 AM. Reason: typo


  2. #2
    Member Kool Parts's Avatar
    Join Date
    Jan 2004
    Location
    USA
    Posts
    536
    Downloads
    0
    Uploads
    0

    Default

    This is a cut and paste of a answer I gave to a similar question a while back.
    Gary

    I have done some extensive testing with different adhesives and 6061. The best by far is Locktite E-30-CL. Used to be known as Locktite glass bonder.

    Its clear and has a 30 min working life. Found this as a tip from a Locktite engineer years ago. He said that it outperformed all of there other products for alum.

    I have put this stuff through shear tests you wouldn't believe..That said it might just eat plastic for lunch! But for $8.00 you get a 50ml twin syringe set...so a pretty cheap test. Part #29329
    Gary




  3. #3
    Member RotarySMP's Avatar
    Join Date
    Mar 2004
    Location
    Vienna, Austria
    Posts
    1257
    Downloads
    5
    Uploads
    0

    Default

    To bond aluminium you need to get the epoxy to bond to Al, and not to the oxide. You need a method of stripping off the oxide, then keeping it from reacting with oxygen wheil applying the glue.

    Is this job structural or just decorative.

    Regards,
    Mark


  4. #4
    Registered
    Join Date
    May 2007
    Location
    UK
    Posts
    767
    Downloads
    1
    Uploads
    0

    Default

    Hi Nelson

    Forgive me asking but why? The cost of the glue could exceed the cost of some new bar stock. The problem with any laminated material is that the glue lines represent possible fault lines if the part is stressed. The exceptions being where the laminated material is porus as in wood or cloth where the composite laminate can be stronger than the materials used on their own.

    If the parts are stressed take into account that the glue used may soften with exposure to water or other solvent - shatter under impact - have a restricted usage temperature range. In other word know the glues limits.

    Hope this helps

    Pat



  5. #5
    Registered
    Join Date
    Apr 2005
    Location
    Brazil
    Posts
    101
    Downloads
    0
    Uploads
    0

    Default thanks

    Thanks a lot, fellows - All very good replies.

    RotarySMP : unfortunately, it is a structural job.

    wildwestpat: yes, I know - adhesives have a lot of restrictions - not to mention temperature;
    they are organic compounds, so they give up at 200 to 300 Centigrade max, while most
    metals are still holding...

    My problem is actually the supplier: The people I buy extrusions from only sell them in whole
    pieces, ie: 6 meters minimum. @ around US$12 per kilo, it gets expensive pretty fast for
    the thicker stuff... I have to find someone that sells cut pieces...

    Thanks again

    Nelson

    Last edited by Arquibaldo; 10-29-2009 at 05:55 PM. Reason: typo


  6. #6
    Community Moderator ger21's Avatar
    Join Date
    Mar 2003
    Location
    Shelby Township
    Posts
    34607
    Downloads
    0
    Uploads
    0

    Default

    Use this before epoxying.
    http://www.westsystem.com/ss/surface-prep

    Gerry

    UCCNC 2017 Screenset
    http://www.thecncwoodworker.com/2017.html

    Mach3 2010 Screenset
    http://www.thecncwoodworker.com/2010.html

    JointCAM - CNC Dovetails & Box Joints
    http://www.g-forcecnc.com/jointcam.html

    (Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)


  7. #7
    Registered
    Join Date
    Sep 2004
    Location
    Canada
    Posts
    209
    Downloads
    0
    Uploads
    0

    Default

    Unless my math is out, a 6 meter piece of 2" x 3/8" is going to run you about US$95. If it is a paying job, I don't see how it's worth the hassle to bother with epoxy. Actually, even if it is a non-paying job, I would still use a solid extrusion.

    If you can't transport pieces 6 meters long, you could always bring along a hack saw and make 1 or 2 cuts before loading the material into your vehicle.



  8. #8
    Registered
    Join Date
    May 2007
    Location
    UK
    Posts
    767
    Downloads
    1
    Uploads
    0

    Default

    Hi Nelson

    Try ebay or Google for a mail order supplier. Think this is your best bet.

    Regards

    Pat



  9. #9
    Member lancut's Avatar
    Join Date
    Nov 2008
    Location
    USA
    Posts
    396
    Downloads
    0
    Uploads
    0

    Talking

    Try rivets, in the aircraft industry this is done on structural assemblies that have to stand up to bending and extreme temperature effects. Google for more info...

    My 2¢


  10. #10
    Registered
    Join Date
    Oct 2006
    Location
    USA
    Posts
    669
    Downloads
    0
    Uploads
    0

    Default

    Yes...it's called welding. Seriously...laminated aluminum extrusions in lieu of using whole material? Sounds dodgy to me. Just make sure you don't try to sell any of that crap to me.



  11. #11
    Registered
    Join Date
    Apr 2005
    Location
    Brazil
    Posts
    101
    Downloads
    0
    Uploads
    0

    Default Thanks again

    ger21: Thanks, I'll see if this product is available here.

    ckirchen: Unfortunately, it isn't a money-making job - it is a money-wasting job: my poor
    attempts at building a tabletop CNC router... Any single expense larger than
    20 or 30 dollars is a red flag in front of "the one who must be obeyed".
    Besides, there is a problem of availability: Thin extrusions are easy to find,
    while anything beyond 1/8" is almost always out-of stock.
    As for transporting the extrusions, I've been doing that for years: they cut the
    pieces in half for me, and they then fit precisely in my car...

    wildwestpat: Yes, ebay... If only I lived in a first-world country...

    bronek: Yes, I know - Rivets aren't practical for me, but I would make sure that no piece
    would depend only on the adhesive - there would always be a few screws
    contributing to keep the laminations together. The adhesive would only be
    responsible for additional rigidity.

    307startup: Very cute and elegant contribution - don't worry - I won't try to sell this crap
    to you or to anyone else - it is crap for strictly private use.

    Nelson

    Last edited by Arquibaldo; 10-30-2009 at 12:06 AM. Reason: typos


  12. #12
    Registered
    Join Date
    Oct 2006
    Location
    USA
    Posts
    669
    Downloads
    0
    Uploads
    0

    Default

    Well if that is the case, what would be wrong with offset holes in each layer of extrusion, and plug welding these holes as you stack the layers? This would in effect make your available extrusions all one piece.

    _o_o_o_o_
    o_o_o_o_o
    _o_o_o_o_

    Quote Originally Posted by Arquibaldo View Post
    ger21: Thanks, I'll see if this product is available here.

    ckirchen: Unfortunately, it isn't a money-making job - it is a money-wasting job: my poor
    attempts at building a tabletop CNC router... Any single expense larger than
    20 or 30 dollars is a red flag in front of "the one who must be obeyed"
    As for transporting the extrusions, I've been doing that for years: they cut the
    pieces in half for me, and they then fit precisely in my car...

    wildwestpat: Yes, ebay... If only I lived in a first-world country...

    bronek: Yes, I know - Rivets aren't practical for me, but I would make sure that no piece
    would depend only on the adhesive - there would always be a few screws
    contributing to keep the laminations together. The adhesive would only be
    responsible for additional rigidity.

    307startup: Very cute and elegant contribution - don't worry - I won't try to sell this crap
    to you or to anyone else - it is crap for strictly private use.

    Nelson




Page 1 of 2 12 LastLast

Tags for this Thread

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


About CNCzone.com

    We are the largest and most active discussion forum for manufacturing industry. The site is 100% free to join and use, so join today!

Follow us on


Our Brands

Bonding aluminum to aluminum - Doable? How?

Bonding aluminum to aluminum - Doable? How?

Bonding aluminum to aluminum - Doable? How?