Page 1 of 4 1234 LastLast
Results 1 to 15 of 47

Thread: FWW's article on Glue-Ups Fact or Fiction?

  1. #1
    Join Date
    Feb 2003
    Location
    New Orleans LA
    Posts
    1,335

    FWW's article on Glue-Ups Fact or Fiction?

    Did anyone else have fear struck in their heart by FWW's article on how to glue up a panel. I've obviously been doing it all wrong for 40 years. I expect the next time I look at a panel I've done I'll be watching it come apart as I watch. I'm not arguing with the author, but I'm sure I've been using a lot less clamps and a lot less pressure than he recommends. Yet I look at panels every day and can't think of one that has failed.

    What do the rest of you think?

    The author's credentials are impressive; so I feel uncomfortable in questioning his conclusions. But . . .
    18th century nut --- Carl

  2. #2
    Join Date
    Dec 2005
    Location
    Long Island, NY
    Posts
    558
    Slightly OT, but what struck me was the fact that a Quick-Grip clamp was rated at 470lb, whereas a parallel jaw clamp was rated at 370lb.

  3. #3
    Join Date
    Oct 2006
    Location
    Mid Michigan
    Posts
    3,537
    I have never found that credentials are written in stone when it comes to things that I have experienced and work for me, but I am not beyond learning from someone else's expertise. If it makes sense maybe the author has a good point. If not, why change now?
    David B

  4. #4
    Join Date
    Feb 2003
    Location
    New Orleans LA
    Posts
    1,335

    Me Too

    Quote Originally Posted by Alex Berkovsky View Post
    Slightly OT, but what struck me was the fact that a Quick-Grip clamp was rated at 470lb, whereas a parallel jaw clamp was rated at 370lb.
    I have to doubt him on this or he had a gorilla using the Quick Grip. When I've tried to bring a tight joint together with the Quick grip and failed a parallel jaw has worked.
    18th century nut --- Carl

  5. #5
    Join Date
    Mar 2003
    Location
    Southport, NC
    Posts
    2,919
    Before we get to far afield, let me point out that the two manufacturers of PVA adhesive (Franklin and Borden) specify the clamp pressure quoted by the author. In addition, the USDA, Wood Products Laboratory in their Wood Handbook specify the same clamping pressure.

    Also, a properly prepared joint will hold together with less pressure. But, for maximum strength and minimal glue line, the higher pressure is required.
    Howie.........

  6. #6
    Join Date
    Mar 2007
    Location
    PA
    Posts
    11,234
    He's probably correct about clamping pressure needed, but I find the ranking of the clamps kind of hard to believe.

    You can bend bessey clamps - they have to be putting out more than 300 pounds of pressure when the bar is bending.

    It seems better to spend the time making the joints right so you don't have to clamp the shizz out of them.

  7. #7
    Join Date
    Mar 2003
    Location
    Redwood City, CA
    Posts
    6,429
    Like you, Carl, I find that article does not ring true. PVA works just fine under far less pressure than he recommends. For instance, mortise and tenon joints generally don't get any pressure across the glue line, but they work. Wiped joints, too, work just fine in PVA, and they have zero applied pressure. In panel glue-up, I rarely use as many clamps as he recommends, but if I test the butt joint to failure, it is the wood that fails, not the glue.

  8. #8
    Join Date
    Oct 2005
    Location
    Plymouth County, Massachusetts
    Posts
    2,933
    As I was reading that last nite, I almost choked when I seen how many clamps that guy was using. He said that you need so many that there wouldn't be enough room to put all the quik clamps.
    I don't know though, about labels. If you read the label on finishing products, it tells you not to dilute the contents. What it doesn't tell you is that they took out the mineral spirits to comply with VOC laws. You have to actually thin your finishing products because they are too thick but they can't tell the consumer that information.
    Gary

  9. #9
    Join Date
    Oct 2006
    Location
    central iowa
    Posts
    142
    Quote Originally Posted by David Weaver View Post
    He's probably correct about clamping pressure needed, but I find the ranking of the clamps kind of hard to believe.

    You can bend bessey clamps - they have to be putting out more than 300 pounds of pressure when the bar is bending.

    It seems better to spend the time making the joints right so you don't have to clamp the shizz out of them.
    Wouldn't the psi of clamps be tied to the surface area of the jaws? The big clamps have a ton more surface area available.

  10. #10
    Join Date
    Oct 2005
    Location
    Plymouth County, Massachusetts
    Posts
    2,933
    Quote Originally Posted by josh bjork View Post
    Wouldn't the psi of clamps be tied to the surface area of the jaws? The big clamps have a ton more surface area available.
    They are if you can get the torque. They said the "T" handle clamps gave the best torque.
    GK

  11. #11
    Join Date
    Mar 2007
    Location
    PA
    Posts
    11,234
    Quote Originally Posted by josh bjork View Post
    Wouldn't the psi of clamps be tied to the surface area of the jaws? The big clamps have a ton more surface area available.

    I guess what I'm getting at is that I use parallel bar clamps for almost everything, and I think that when you can get a good grip on them, you can bend the bar some, even when the spread isn't that far.

    The PSI at the joint shouldn't reflect the amount of surface area of the clamps - if they're clamping with 500 pounds of pressure, that's 500 pounds. I sure would worry about the wood fibers on a cherry panel using one of those iron bar clamps with 1500 psi of pressure. I'm assuming that you're saying that you can get a lot more clamping pressure at the same psi at the jaws of the clamp if you use the bessey style clamps.

    I'm still a bit of a newbie, though - maybe it's more important if you're throwing things together straight off the table saw or machine jointer. I have never put a panel together without planing the edge until there is no light under a starret edge, aside from maybe a tiny fraction so that the straight edge pivots on the ends of the jointed board.

    Production for the guys on here who do this for a living is, I guess, a far different thing.

  12. #12
    Join Date
    May 2007
    Location
    Summit, New Jersey
    Posts
    70

    Exclamation

    Quote Originally Posted by Alex Berkovsky View Post
    Slightly OT, but what struck me was the fact that a Quick-Grip clamp was rated at 470lb, whereas a parallel jaw clamp was rated at 370lb.
    Me too. That's really all I wanted to say, but the forum software apparently needed a longer message for some reason, so I'm writing more here
    Visit Peercon.com

  13. #13
    Join Date
    Oct 2005
    Location
    Plymouth County, Massachusetts
    Posts
    2,933
    I always make my panels a couple inches bigger then necessary and when I lay out the boards for the most pleasing face I check for light between the boards. I work the edges until all the boards are straight enough to go together by hand without any pressure.
    Seems to me the straighter the board.....I never BEND the board with the clamps to make it straight. Does this post make any sense? LOL
    Gary

  14. I build all kinds of custom wood pieces for a living.I use the Jorgensen 72 steel bar clamps and I find these to be the best.All my panel pieces are cut,jointed,and then rev. glue jointed on the shaper.I also use Titebond.In thirty fiveyears,I've never had a problem with a panel failure,or any kind of Glue failure.I admit that I did't read the article,but he is definitly wrong about the hand-squeeze type clamps.

    Oscar

  15. #15
    Join Date
    Dec 2006
    Location
    Tucson
    Posts
    4,973
    Blog Entries
    1
    Quote Originally Posted by Alex Berkovsky View Post
    Slightly OT, but what struck me was the fact that a Quick-Grip clamp was rated at 470lb, whereas a parallel jaw clamp was rated at 370lb.
    I said the exact same thing to my BIL last night. I feel that there needs to be some glue left in the joint to, well, glue it together. As far as those clamping preasures go, that can't be correct.
    What you listen to is your business....what you hear is ours.

Similar Threads

  1. Are Your Glue Joints Repairable?
    By Bob Smalser in forum General Woodworking and Power Tools
    Replies: 86
    Last Post: 09-26-2010, 12:22 AM
  2. CA Glue
    By John Esberg in forum Engravers Forum
    Replies: 13
    Last Post: 09-30-2006, 10:45 PM
  3. Maybe I Don't Understand
    By George Summers in forum General Woodworking and Power Tools
    Replies: 2
    Last Post: 11-05-2005, 5:43 PM
  4. The USDA Bottom Line on Poly Glue
    By Bob Smalser in forum General Woodworking and Power Tools
    Replies: 2
    Last Post: 01-31-2005, 11:55 PM
  5. Gorilla Glue
    By Betsy Yocum in forum General Woodworking and Power Tools
    Replies: 14
    Last Post: 08-02-2004, 1:15 PM

Posting Permissions

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