Veneer

You are not logged in. [ Login ] Why log in
(NOTE: Login is not required to post)

Glue Up Misshap

5/2/13       
Tim G

I'm working on veneering a large table top,60'' x 108''. Plan was to build it as a torsion box, two ply top and bottom. First glue up two plys, then veneer box, all with a vacuum press. Due to the size and number of pieces on the face I first glued up bottom, quartered Mahogany with poplar perpendicular. It went well, too well as I left it in the vacuum all night,and like to never separated it from the 1/2 melamine cauls.I did get it apart with some dime size pieces torn off. Luckily it's the bottom and I've made decent repairs. Never had melamine stick so bad, thought maybe the new formulation of uni-bond was to blame. Next came the top, 12 piece matched Amboyna burl with outer inlay with Sapele border.Intent not to have the sticking issue occur I glued it up, and broke it apart after glue set, about four hours. It was stuck lightly but separated easily. I left it between melamine cauls overnight. This morning I took it out and I have major separation and bond failure, all over the piece. It's hundreds down the drain. I need to figure out how to proceed from here. I waxed the cauls, yet it was trying to stick, but obviously I took it out to soon. I know if I left it in it would have stuck hard. Is the new formulation to blame, I never had it stick so bad with the old. I considering hammer veneering the next try. This job's a loss as of now, can't afford another mistake.

5/2/13       #2: Glue Up Misshap ...
Tom E Member

Tim,

Next time try a thin plastic painting tarp which you can get at any hardware store. I have read on different forums that the new uni-bond is very finicky when it comes to temperature! Are you able to save any part of the face?

5/2/13       #3: Glue Up Misshap ...
Tim G

Yes, I'll definitely use plastic next time. I actually was able to save the burl pieces with little damage by carefully using a 10'' drywall knife and ever so gently prying it apart. Took the better part of the day, but at near $20 per foot it was worth it.I had an extra 4 pieces so I should be good to go. I'm not sure as to whether I should lightly sand the glue side and reglue it, or flip the pieces glue side up and sand it off after pressing. Not sure what kind of bond I can expect if I use the glued side down.

5/2/13       #4: Glue Up Misshap ...
Bob

Plastic between the caul and veneer is going to prevent this from happening again, at least the sticking part. You could try switching to Pro Glue UF, I've been using it for years and will never go back to Unibond. Not as temperature sensitive, longer shelf life and lower Formaldehyde content. That and I've had a couple too many problems with Unibond discoloring light colored veneers.

5/3/13       #5: Glue Up Misshap ...
David R Sochar Member

Website: http://www.acornwoodworks.com

Tim - That is one sad tale, but sounds recoverable. I also suggest the plastic sheeting - cheap, easy and fool-proof. I used a lot of 'shower liner' for cauls - white masonite sheet stock that usually resists glue, but after a few uses starts sticking. I used to wax it, then just inserted the plastic sheet.

Bob....tell me more about the "Pro glue UF". Google doesn't get me much. Who makes it, where can I get it.

I have used Unibond for years and just recently had a few places on a large table that did not bond well - first time for that problem. Shop and materials all heated beyond specs, etc, but still a problem - not happy. Previously, I had problems with Uni-bond and discoloring Maple veneers.

5/3/13       #6: Glue Up Misshap ...
John Van Brussel

Website: http://www.veneersystems.com

We don't sell Pro Glue but sell a product which is similar and we sell a lot of it. We also sell Unibond 800 and the formula was changed a year ago. They removed 90% of the urea formaldehyde. Both glues can be tinted using titanium dioxide to lighten the glue and any water soluble dye to darken them.

Veneer Systems products

5/3/13       #7: Glue Up Misshap ...
Tim G

Thanks for all the input. Any thoughts as to which side of the recovered veneer I should re-glue ? I'm doing a small test panel doing it both ways, but would like to hear more. I like the idea of using a shower curtain, good call, easy to lay out I imagine. I may switch glue as John suggests, but I'm a little nervous about introducing that much water on such a large piece. Then again this new and improved formula has aged me ten years! Green my #?!! :)

5/3/13       #8: Glue Up Misshap ...
David R Sochar Member

Website: http://www.acornwoodworks.com

I also do not like to add any water to my layups, so that is why I always used the Uni-Bond 800. I assume it has some water, but ??? I'm curious as to any feedback on that part of the discussion.

Also, I use 'shower liner' - a 1/8" x 4 x 8 masonite board that is painted with a heavy white paint on one side for the cauls. About 5.00 a sheet at the Home Center. Then I use just plain plastic sold as painter's tarps or whatever - heavy enough gauge to re-use.

5/3/13       #9: Glue Up Misshap ...
Tom E Member

Tim
How are your seams held together? If you used veneer tape I would not put them in the glue line. Is the unibond hard on the glue panel if so go with that side? What glue are you using for your test sample? Tom

5/3/13       #10: Glue Up Misshap ...
Tim G

Tom,
I used uni-bond on the new sample, one glue side up, one down. I'll check bond Monday, and probably blow a coat of finish to see if there's a difference. I used veneer tape, so I'll scrape it off if I go glue side up on the top.

5/5/13       #11: Glue Up Misshap ...
Bob

David, I get my Pro Glue from the manufacturer here is CA, Vac-U-Clamp - see link below.

They also have a few other glue options in case UF isn't your first choice. I stopped using Unibond years ago after a few bad glueups. So far no problems with ProGlue, it is water based though. Comes as a dry powder in either tan or white and is mixed with water. The two colors can be blended for different shades of tan/brown. The powder has a very long shelf life compared to Unibond.

Vac-U-Clamp

5/6/13       #12: Glue Up Misshap ...
David R Sochar Member

Website: http://www.acornwoodworks.com

Bob - Now I see I have used Pro-Glue before. It is one that we use for 'butcher block' glue ups, but it needs 70 degrees or better. I'd love to get that temperature down to 60 or warmer, but I have seen failures at just under 70.

Also, do you have any problems with thin veneers in sketch faces expanding or moving with the 'water' that is inherent in the mix?

5/6/13       #13: Glue Up Misshap ...
John Van Brussel

Website: http://www.veneersystems.com

Both Unibond 800 and plastic resin glues contain water. The plastic resin glues are a pre catalyzed resin powder which when you mix in the water restarts the chemical reaction bond. Unibond 800 is a liquid resin with water in it and you add the powdered catalyst to the resin to restart the chemical reaction bond. Both of these types of UF need to be 70F or warmer to cure properly. There should be no issues with the water as this a chemical reaction bond not an evaporative bond like PVA's. PVA's are thermo plastic and do not dry hard. In Germany the UF glues are called Hart leim which translates to hard glue.

5/6/13       #15: Glue Up Misshap ...
Tom E Member

John, doesn’t unibond have alcohol in it that gives it that nice smell?
Tim how did your test pieces turn out?

5/6/13       #16: Glue Up Misshap ...
Tim G

Tom,
Both samples turned out fine, no bond issues with either one. I sanded and put a clear coat on and you cannot tell which is which, so it looks like I'll be gluing it glue side down after a light sanding.. That's what Darryl Keil over at Vucupress.com suggested as well.

5/6/13       #17: Glue Up Misshap ...
Tom E Member

Tim,
So does it come down to the time it stays in the press more than temp? Or is it both? Also what did you use to cut your seams? Tom

5/6/13       #18: Glue Up Misshap ...
John Van Brussel

Website: http://www.veneersystems.com

Yes it is 21% furfuryl alcohol. The Physical and Chemical description from the MSDS states "Off white, water solution of urea formaldehyd resin and furfuryl alcohol.
Odor: formaldehyde, furfuryl alcohol."

5/6/13       #19: Glue Up Misshap ...
Tim G

Tom,
Temp was 75F so it's just a matter of leaving it in longer. I should have intuitively known that two ply would want to move more than a regular layup. I use veneer tape to seam.

5/23/13       #20: Glue Up Misshap ...
Ian Hawthorne

Website: http://www.hawthornecrafts.com

Non stick baking paper - comes in rolls and nothing sticks to it.

Ian

5/24/13       #21: Glue Up Misshap ...
Rich

Get yourself a couple of pieces of Mylar. It's a little expensive, but nothing sticks to it, I mean nothing and you'll get years of use from it if you take care of it.

6/5/13       #22: Glue Up Misshap ...
Tim G

Thought I'd give an update on the top. Just finished rubbing it out, ready to set on the base.


View higher quality, full size image (600 X 450)

6/5/13       #23: Glue Up Misshap ...
David R Sochar Member

Website: http://www.acornwoodworks.com

Looks like you were able to make it all work. Nice work!

6/5/13       #24: Glue Up Misshap ...
Rich

Nice job, table looks great.

6/5/13       #25: Glue Up Misshap ...
Tom E Member

Tim,
Looks great thanks for sharing. Tom


Post a Response
  • Notify me of responses to this thread
  • Subscribe to email updates on this Forum
  • To receive email notification of additions to this forum thread,
    enter your name and email address, and then click the
    "Keep Me Posted" button below.

    Please Note: If you have posted a message or response,
    do not submit this request ... you are already signed up
    to receive notification!

    Your Name:
    E-Mail Address:
    Enter the correct numbers into the field below:
     

    Date of your Birth:



    Return to top of page

    Buy & Sell Exchanges | Forums | Galleries | Site Map

    FORUM GUIDELINES: Please review the guidelines below before posting at WOODWEB's Interactive Message Boards (return to top)

  • WOODWEB is a professional industrial woodworking site. Hobbyist and homeowner woodworking questions are inappropriate.
  • Messages should be kept reasonably short and on topic, relating to the focus of the forum. Responses should relate to the original question.
  • A valid email return address must be included with each message.
  • Advertising is inappropriate. The only exceptions are the Classified Ads Exchange, Machinery Exchange, Lumber Exchange, and Job Opportunities and Services Exchange. When posting listings in these areas, review the posting instructions carefully.
  • Subject lines may be edited for length and clarity.
  • "Cross posting" is not permitted. Choose the best forum for your question, and post your question at one forum only.
  • Messages requesting private responses will be removed - Forums are designed to provide information and assistance for all of our visitors. Private response requests are appropriate at WOODWEB's Exchanges and Job Opportunities and Services.
  • Messages that accuse businesses or individuals of alleged negative actions or behavior are inappropriate since WOODWEB is unable to verify or substantiate the claims.
  • Posts with the intent of soliciting answers to surveys are not appropriate. Contact WOODWEB for more information on initiating a survey.
  • Excessive forum participation by an individual upsets the balance of a healthy forum atmosphere. Individuals who excessively post responses containing marginal content will be considered repeat forum abusers.
  • Responses that initiate or support inappropriate and off-topic discussion of general politics detract from the professional woodworking focus of WOODWEB, and will be removed.
  • Participants are encouraged to use their real name when posting. Intentionally using another persons name is prohibited, and posts of this nature will be removed at WOODWEB's discretion.
  • Comments, questions, or criticisms regarding Forum policies should be directed to WOODWEB's Systems Administrator
    (return to top).

    Carefully review your message before clicking on the "Send Message" button - you will not be able to revise the message once it has been sent.

    You will be notified of responses to the message(s) you posted via email. Be sure to enter your email address correctly.

    WOODWEB's forums are a highly regarded resource for professional woodworkers. Messages and responses that are crafted in a professional and civil manner strengthen this resource. Messages that do not reflect a professional tone reduce the value of our forums.

    Messages are inappropriate when their content: is deemed libelous in nature or is based on rumor, fails to meet basic standards of decorum, contains blatant advertising or inappropriate emphasis on self promotion (return to top).

    Libel:   Posts which defame an individual or organization, or employ a tone which can be viewed as malicious in nature. Words, pictures, or cartoons which expose a person or organization to public hatred, shame, disgrace, or ridicule, or induce an ill opinion of a person or organization, are libelous.

    Improper Decorum:   Posts which are profane, inciting, disrespectful or uncivil in tone, or maliciously worded. This also includes the venting of unsubstantiated opinions. Such messages do little to illuminate a given topic, and often have the opposite effect. Constructive criticism is acceptable (return to top).

    Advertising:   The purpose of WOODWEB Forums is to provide answers, not an advertising venue. Companies participating in a Forum discussion should provide specific answers to posted questions. WOODWEB suggests that businesses include an appropriately crafted signature in order to identify their company. A well meaning post that seems to be on-topic but contains a product reference may do your business more harm than good in the Forum environment. Forum users may perceive your references to specific products as unsolicited advertising (spam) and consciously avoid your web site or services. A well-crafted signature is an appropriate way to advertise your services that will not offend potential customers. Signatures should be limited to 4-6 lines, and may contain information that identifies the type of business you're in, your URL and email address (return to top).

    Repeated Forum Abuse: Forum participants who repeatedly fail to follow WOODWEB's Forum Guidelines may encounter difficulty when attempting to post messages.

    There are often situations when the original message asks for opinions: "What is the best widget for my type of shop?". To a certain extent, the person posting the message is responsible for including specific questions within the message. An open ended question (like the one above) invites responses that may read as sales pitches. WOODWEB suggests that companies responding to such a question provide detailed and substantive replies rather than responses that read as a one-sided product promotion. It has been WOODWEB's experience that substantive responses are held in higher regard by our readers (return to top).

    The staff of WOODWEB assume no responsibility for the accuracy, content, or outcome of any posting transmitted at WOODWEB's Message Boards. Participants should undertake the use of machinery, materials and methods discussed at WOODWEB's Message Boards after considerate evaluation, and at their own risk. WOODWEB reserves the right to delete any messages it deems inappropriate. (return to top)


  • Forum Posting Help
    Your Name The name you enter in this field will be the name that appears with your post or response (return to form).
    Your Website Personal or business website links must point to the author's website. Inappropriate links will be removed without notice, and at WOODWEB's sole discretion. WOODWEB reserves the right to delete any messages with links it deems inappropriate. (return to form)
    E-Mail Address Your e-mail address will not be publicly viewable. Forum participants will be able to contact you using a contact link (included with your post) that is substituted for your actual address. You must include a valid email address in this field. (return to form)
    Subject Subject may be edited for length and clarity. Subject lines should provide an indication of the content of your post. (return to form)
    Thread Related Link and Image Guidelines Thread Related Links posted at WOODWEB's Forums and Exchanges should point to locations that provide supporting information for the topic being discussed in the current message thread. The purpose of WOODWEB Forums is to provide answers, not to serve as an advertising venue. A Thread Related Link that directs visitors to an area with inappropriate content will be removed. WOODWEB reserves the right to delete any messages with links or images it deems inappropriate. (return to form)
    Thread Related File Uploads Thread Related Files posted at WOODWEB's Forums and Exchanges should provide supporting information for the topic being discussed in the current message thread. Video Files: acceptable video formats are: .MOV .AVI .WMV .MPEG .MPG .MP4 (Image Upload Tips)   If you encounter any difficulty when uploading video files, E-mail WOODWEB for assistance. The purpose of WOODWEB Forums is to provide answers, not to serve as an advertising venue. A Thread Related File that contains inappropriate content will be removed, and uploaded files that are not directly related to the message thread will be removed. WOODWEB reserves the right to delete any messages with links, files, or images it deems inappropriate. (return to form)