Page 1 of 2 12 LastLast
Results 1 to 15 of 27

Thread: Glue for rub joints?

  1. #1

    Glue for rub joints?

    I'm getting started on the chest of drawers from "The Joiner and Cabinet Maker", right now I'm still working on stock prep before gluing up my panels for the case. I've always found clamping and glue ups to be the thing I enjoy least in woodworking, so learning about rub joints as a way to do long edge joints without clamps has been intriguing. If I can make the process more enjoyable, why not? I'm doing this as a hobby after all.

    I've done a shorter practice rub joint with Titebond III on some white pine that I think came out pretty good (the glue line came out thicker than with clamped joints, but it's still acceptably thin), and I'm pretty sure with a bit more practice I could make an even better joint.

    What glues are really best for rub joints? I know these were traditionally done with hot hide glue (I've got a small package to try out on the way in the mail), and most of the sources I've seen say you can do rub joints with PVA glues, but it's really recommend to clamp joints with PVA glues... On the other hand, watching WoodbyWright's glue testing videos on youtube, it seems like hide glue is definitely weaker, and has poorer gap filling performance than a good quality PVA glue like Titebond III. Maybe that doesn't matter anyway since hot hide glue was used for rub joints for centuries.

    I'm interested to hear what you folks on the creek have to say!

  2. #2
    Join Date
    Dec 2010
    Location
    South Coastal Massachusetts
    Posts
    6,481
    Titebond II has a shorter open time and dries (essentially) clear. Titebond 3 has a longer "open" time and dries a brown hue - it emulates hide glue.

    Rub joints are traditionally made with hide glue, which begins to shrink as it cools, and draws joints tight.

    It is prone to failure in damp environments, like most basement shops.

  3. #3
    Join Date
    Aug 2019
    Location
    Pittsburgh, PA
    Posts
    219
    You may want to try pinch dogs as clamp substitutes.

    For example,
    https://www.amazon.com/dp/B00JJZACQE..._TFJYFb4P07BRB

  4. #4
    Rub joints may not be appropriate on all joints.

    I would simultaneously investigate cauls. They reduce stress during glue up too.

  5. #5
    Quote Originally Posted by Laurent Marshall View Post
    I'm getting started on the chest of drawers from "The Joiner and Cabinet Maker", right now I'm still working on stock prep before gluing up my panels for the case. I've always found clamping and glue ups to be the thing I enjoy least in woodworking, so learning about rub joints as a way to do long edge joints without clamps has been intriguing. If I can make the process more enjoyable, why not? I'm doing this as a hobby after all.

    I've done a shorter practice rub joint with Titebond III on some white pine that I think came out pretty good (the glue line came out thicker than with clamped joints, but it's still acceptably thin), and I'm pretty sure with a bit more practice I could make an even better joint.

    What glues are really best for rub joints? I know these were traditionally done with hot hide glue (I've got a small package to try out on the way in the mail), and most of the sources I've seen say you can do rub joints with PVA glues, but it's really recommend to clamp joints with PVA glues... On the other hand, watching WoodbyWright's glue testing videos on youtube, it seems like hide glue is definitely weaker, and has poorer gap filling performance than a good quality PVA glue like Titebond III. Maybe that doesn't matter anyway since hot hide glue was used for rub joints for centuries.

    I'm interested to hear what you folks on the creek have to say!
    Laurent,

    Use hot hide glue. Other glues, even liquid hide glue, have problems with doing a rub joint. As for the strength of the joint who cares about WoodbyWright's videos, I've yet to break a rub joint where the wood didn't fail before the glue.

    ken

  6. #6
    I would not use a rub joint on anything that will be structural or under stress. I would not use it to glue up large panels. I find hot hide glue is the absolute best for rub joints because it’s so fast and doesn’t leave a very visible line. Elmer’s glue-all is also a good one – although considerably slower to set up, it leaves an almost invisible line. By way of contrast, something like TB III leaves a hideous dark brown line so depending on the color of your wood you might not be very happy.

    Gap filling is meaningless with a rub joint because in theory there should be zero gaps on a rub joint. If you’ve got any gaps, don’t do a rub joint.

    One thing to consider is that if what you hate about clamping is the clamping time, hot hide glue joints that aren't under stress DURING the glue up don't need to be clamped for long at all.

  7. #7
    Quote Originally Posted by Rafael Herrera View Post
    You may want to try pinch dogs as clamp substitutes.

    For example,
    https://www.amazon.com/dp/B00JJZACQE..._TFJYFb4P07BRB
    Those those might be worth a try - I guess they're mostly good to reduce the chance of the boards shifting before the glue has set. I'm not sure they'd provide much clamping pressure, and theoretically with a perfect rub joint with hot hide glue you shouldn't need any...

    Although I don't enjoy using clamps, going clamp-less does make me a bit nervous!

  8. #8
    Quote Originally Posted by chris carter View Post
    I would not use a rub joint on anything that will be structural or under stress. I would not use it to glue up large panels. I find hot hide glue is the absolute best for rub joints because it’s so fast and doesn’t leave a very visible line. Elmer’s glue-all is also a good one – although considerably slower to set up, it leaves an almost invisible line. By way of contrast, something like TB III leaves a hideous dark brown line so depending on the color of your wood you might not be very happy.

    Gap filling is meaningless with a rub joint because in theory there should be zero gaps on a rub joint. If you’ve got any gaps, don’t do a rub joint.

    One thing to consider is that if what you hate about clamping is the clamping time, hot hide glue joints that aren't under stress DURING the glue up don't need to be clamped for long at all.
    Mostly what I don't like about clamping is the set up and then fiddling with and setting all the clamps well. It's just a lot of pieces to handle, and even with cauls you still often need a ton of clamps as the cauls will only spread the clamping pressure an extra few inches sometimes. Not dealing with clamps for a glue up would just be kind of nice. If a part of the process is not enjoyable, and there's another way to get a good result, why bother with the less enjoyable method? I certainly want my projects to last, but on the other hand I'm not doing this for paying customers.

  9. #9
    Quote Originally Posted by ken hatch View Post
    Laurent,

    Use hot hide glue. Other glues, even liquid hide glue, have problems with doing a rub joint. As for the strength of the joint who cares about WoodbyWright's videos, I've yet to break a rub joint where the wood didn't fail before the glue.

    ken
    I guess "use the hot hide glue and don't worry about it" is one way to go!

  10. #10
    Because going clampless is not something most people do. There’s a reason. Cauls spread the pressure over longer distances. I’ve done them up to 4 feet. Imho you’ll reduce your long term stress and be a better woodworker if you both learn to joint as if you’re doing a run joint but also learn to use clamps more efficiently and to utilize dominos or dowels for alignment. Draw boring is anothe fantastic technique worthy of study.

    Stress is reduced by having options not by religiously sticking to one method.

  11. #11
    Join Date
    Nov 2013
    Location
    Crozet, VA
    Posts
    383
    For me the stress of glue ups comes from the "being on the clock" with the limited set time of the glue, especially for complex glue-ups. That's why I really prefer working with longer open time glues like Titebond Extend or Plastic Resin glue. Something to check out if you haven't already.
    There is a very fine line between “hobby” and “mental illness.” - Dave Barry

  12. #12
    Quote Originally Posted by Laurent Marshall View Post
    Mostly what I don't like about clamping is the set up and then fiddling with and setting all the clamps well. It's just a lot of pieces to handle, and even with cauls you still often need a ton of clamps as the cauls will only spread the clamping pressure an extra few inches sometimes. Not dealing with clamps for a glue up would just be kind of nice. If a part of the process is not enjoyable, and there's another way to get a good result, why bother with the less enjoyable method? I certainly want my projects to last, but on the other hand I'm not doing this for paying customers.
    I totally understand wanting to have fun over the "best way" to do something as I totally fall into that boat! One thing you can try is a sprung joint. If you leave a gap in the middle you only need to clamp the middle. Or leave the hump in the middle and just one clamp on each end. It would at least cut down on the number of clamps.

    Another recommendation I could make is the choice of clamps. I used to get really frustrated because I relied on F clamps a lot. Then one day it hit me that so many old-school woodworking gurus I watched on youtube would use pipe clamps for everything and only resort to other styles when a pipe clamp couldn't work. So I bought more pipe clamps! I used to hate glue ups, but now they aren't so bad. Some people really swear by those aluminum bar clamps. I'm just saying, the style of clamp, or brand of clamp, might be a contributing factor and different people like different things.

    THAT SAID, I must say that although I don't do rub joints very often, when I DO use one there is a certain satisfaction to it!

    P.S. and in agreement with a previous post - if you really want to go hog wild with rub joints, just go hot hide glue and don't look back because everything else will be various levels of compromise.
    Last edited by chris carter; 12-04-2020 at 2:34 PM.

  13. #13
    Join Date
    Jul 2019
    Location
    Northeast WI
    Posts
    293
    There are other options. A spring joint for example where you intentionally leave a small valley in the middle while jointing and then concentrating the clamping pressure in the middle while the ends are "self clamping".

    There are other clampless options as well. I have seen batons and wedges used.

  14. #14
    Hide Glue granules are ...or were sold in different strengths. There is certainly some control in just thinning it ,but set
    time will be longer. I don't like the bottled stuff ,has....obviously a chemical to inhibit set-up . I've seen it fail on a
    carefully used ....is there any other kind? violin.

  15. #15
    Join Date
    Sep 2007
    Location
    Longview WA
    Posts
    22,670
    Blog Entries
    1
    I've always found clamping and glue ups to be the thing I enjoy least in woodworking,
    It may be worth taking a little time to identify the aspects of clamping causing this lack of enjoyment.

    One change to make clamping more enjoyable for me was to get all of my pipe clamps set up before hand. This meant getting them all set up for the size of the pieces being glued. Then laying a few of them lined up with cauls placed strategically on the surface being used for the gluing made it easy to apply the glue and bring the pieces together. Lightly tighten the cauls and then tighten the final holding clamps.

    Planning the sequence can make the job go a lot quicker and with less trepidation.

    jtk
    "A pessimist sees the difficulty in every opportunity; an optimist sees the opportunity in every difficulty."
    - Sir Winston Churchill (1874-1965)

Posting Permissions

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