Moving Workshop Table: Episode 4

Posted 12 June 2019

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We are nearly there with this project now. In this episode Paul glues up the main frame, being careful to get the parts in the right order. Some bits are a somewhat awkward as the rails are quite long. Then, Paul prepares the shelf piece by planing, scraping and sanding it in readiness for installation.

Previous: Moving Workshop Table: Episode 3

16 Comments

  2. It’s really gratifying to see how Paul handles the difficulties.
    Only one side of the tenons of the short rails had the beveled corners, why is that?
    When gluing up the last pair of legs to the frame why didn’t Paul put that pair of legs on the floor and the whole frame on top? Wouldn’t it be easier to do the oposite, and hammering directly on the pair of legs?
    Won’t the blue clamps (that Paul removed the rubber shoe) mark the wood? How does Paul remove that mark?

    1. Hi Antonio,

      Thank you for your questions. Paul says:

      This is called a sloped haunch and the haunches only go to the top of the tenon because it’s not necessary. The haunch facilitates the enclosure of the tenon so it’s only used on the outside of a 90° corner.

      There’s no rhyme or reason to the way I work. I just do what I feel in the moment I was happy with the way things went.

      No, the blue clamps won’t mark the surface. Provided you are sensitive to the amount of pressure you apply. If you are worried, you can always add some packing.

      Kind Regards,
      Izzy

      1. Hi Izzy,

        Thank you for the reply.
        Maybe I didn’t make myself clear on my first question.
        I’m referring to minute 2:50 on the video, where Paul talks about the reason for the chanfered tenon on the top.
        Both the normal tenon and the sloped haunch tenon has the top chanfered.
        But the oposite tenons of the same short rails don’t have (the ones that are already glued in this position in the video). They have a perfect 90 degree angle on the top.
        Is there any particular reason for it?

        Thank you, regards.

  3. I wonder about the length of time it takes for glue ups like this, and for more complicated pieces, given limited working time for glue. Paul is still adding clamps etc 20 minutes into the video! Lots of PVA glues are supposed to have open times of 5 – 10 minutes — though different sources give different times for particular glues, some a bit longer than that. I built Paul’s tool chest (the one with two drawers and a lid) and everything was good when I dry assembled it. But the glue up was a disaster. I assembled all the parts but did not seat the joints fully as I put each one together, assuming the clamps would close them up the last bit and pull everything square. It took me about 8 minutes (or maybe less) to spread glue, assemble everything and add the clamps. In those few minutes, the glue froze everything solid. The joints did not close and the carcass did not come square. No problem, I thought. I smacked the joints with a hammer as I have seen Paul do to break the glue freeze. No joy. I turned the clamps so hard that the wood began to crack and smacked them over and over with the hammer. But the joints would not close that last bit and the whole remained out of square. Makes me wonder what I am doing wrong. Is 8 minutes really too long? I wonder if others have problems like this.

    1. Getting glue freeze is common for me too. But I work much slower; 8 minutes for the tool chest sounds fast to me. Anyway, for a long while now I’ve been using 2002GF (lee valley) or Titebond III and am generally petrified when it comes to glue-up. 2002GF is slightly slower to set than Titebond but not slow enough for me.

      Paul seems to use some brand of white PVA which probably has a longer open time? I used to use Elmers wood glue which takes ample time to set. I’m considering going back to it.

    2. A couple things to try: As you mentioned, _do_ pull the joints tight as you go. Don’t leave it for the end. I guess you need to think about this because every glue up is different and sometimes you do need to let things all find their place, which means not being constrained by clamps, but even in that case I’d be inclined to pull the joint tight and then slack off the clamp while I did the others similarly and then go back tight again all around.

      You want to look for a way to only apply glue to the joints you are immediately putting together. For example, with dovetails, I’ll spread glue on just the first joint and assemble it. Then, I spread the second joint, assemble it, and put a clamp across the pair. This leaves me with two pins, dry and untouched pointing up in the air (not one pin and one tail!!). Spread glue on both quickly, assemble, and clamp. So, I’ve never had more than two joints wet at a time in this case and usually just one. The glue only sat for a couple minutes.

      If you are doing a table, it is similar: Glue up the two end assemblies separately, then bring them together with the long aprons. When you do one of the end assemblies, it can be done one joint at a time on the first leg, then two joints at once to put on the second leg (assuming there are stretchers).

      Even doing this, yes, there can be freeze. The final thing to note is that there is glue freeze (sets up or swells) and there is hydraulic pressure, which is different. Hydraulic pressure is when you put together something like a M&T or dowel, excess glue goes to the bottom, and has nowhere to go when you slide the tenon in. You need to relieve the corners of the tenon or otherwise leave some space for excess glue when cutting the joint. If you develop a hydraulic, there’s a good chance you are in big trouble and will never seat it. If it’s the first joint, you probably can pull it apart. If it is one of the later joints, the others will have set up enough that you probably can’t risk taking it all apart. I don’t know what to suggest for that. I had this happen gluing up a chair with my daughter, and we just had to live with it. Luckily, it still looks good.

  4. Not on topic, but +1 for enabling “edit”. Also I miss “preview” especially when writing a longish comment with some formatting, good to preview and see how it will look.

    Is there a handle to refer to for pinging admins?

  5. There are often very good reasons for the way Paul does things that escape me. Hence my question.
    Paul glued up the whole assembly at one time, and by the end he was high-stepping to get it all to work. I doubt I could move through it all at his speed. I’m fit enough, but not experienced enough.
    Could we get the same results gluing up the end assemblies one at a time, and letting each sit overnight? Then glue the end assemblies to the long stretchers? Glue one end assembly on Monday, the next on Tuesday, and bring them together on Wednesday?
    I am wondering if Paul did it all at once to allow all the joints to move as they got clamped. Does that make any sense?
    And I suppose it might be that he did it all at once for production purposes so we could see it all in one episode.

  6. Suggestion on roughly how far apart to space the screws in the top, and whether to screw two or more layers at a time, would be welcome. Sorry if I missed that in the video or plan.

    Would it be prudent to check for twist, as well as square, in the frame assembly before the glue is fully set? Maybe just two strings corner to corner in an X?

    1. Hi,

      Paul says:
      I think 9” to a foot would be fine. You can screw more layers but just be ready in case something slips or does not seat right. It is always good to consider twist as you go, yes.

      Izzy

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