Results 1 to 15 of 55

Thread: Thoughts about glue-ups and clamps

Threaded View

Previous Post Previous Post   Next Post Next Post
  1. #1

    Thoughts about glue-ups and clamps

    A few weeks ago, I posted about how impressed I was with some new parallel clamps I finally tried. Since then, I've used them more and I'd like to compare notes with all of you on some of my observations about glue ups in general.

    1. First, let me just eat some crow and say that our Pro's were, of course, right. There are certain times that, like it or not, you have to force a joint closed using more pressure than normal. It's not something I have to do often, but I had to get out the pipe clamps yesterday on the final section of that butcher block table. The JETs just wouldn't close the gap.

    2. In my (hobbyist) shop, needing greater clamping force seems to happen when either I haven't done a dry fit to check how it all comes together, or I've fiddled with the wet glue-up until some of it is starting to set up. The partially dried glue has been known to "clog" the gap between two parts, rather like a shim. But if I properly fit my joints ahead of time, I don't seem to need a ton of pressure to get a rock solid glue up (on the things I build). Do you folks see the same - well fit joints need less pressure? Or is that just because I build small, simple stuff, rather than mahogany entry doors?

    3. Parallel clamps won't correct small errors in un-square surfaces. What I mean, is that an F-clamp can swivel a degree or two and bring out of square parts together without leaving a gap. (You'll have to plane the mated boards flat again of course.) But if your parts aren't good and square, the parallel clamp will not create a tight joint - you'll have a thin gap filled with glue with wood touching wood only on one edge.

    4. I'd forgotten how much I hate black pipe. Got crud from the pipe all over my workpiece because I forgot to wipe them down first (in the middle of that glue up). But man, can those stinkers apply force.

    5. Glue gets stuck to parallel clamps. Not sure why it's more of a problem to remove than on F-clamps - the "tracks" look about the same to me - but dried glue does clog them. I wax the tracks and wipe them clean immediately after removing the glued up item. If it's stuck, I clean the track with a brass brush. How do you deal with this?

    6. F-clamps are NOT the solution to everything, especially wide panels. They flex too much. (At least my 24" Jorgey's do.) I never snapped to that until recently. I'm finding that it works best for me to place 4 pipe clamps or parallel clamps on the work, then only use the F-clamps to fill in the gaps between. Even if the joint is fit right, the flex pulls the work out of plane. YMMV and yes, cauls can help with that. But it's so much easier using clamps that don't flex.

    The Best Things has 10 Dubuque 24" clamps for about $210+shipping. I think I'm going to start saving up for a set. I've bought some old planes from there and enjoyed doing business with them.

    7. For narrower glue ups, I really like the Bessey Revo Jr in an 18" length. Lightweight and effective. But again, I wouldn't go longer with the Juniors because of potential flex. I get out the JETs. But that's just me.

    Any thoughts on my observations, or on glue ups in general?

    Fred
    Last edited by Frederick Skelly; 02-26-2017 at 4:36 PM.
    "All that is necessary for the triumph of evil is that good men do nothing."

    “If you want to know what a man's like, take a good look at how he treats his inferiors, not his equals.”

Posting Permissions

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