Page 2 of 2 FirstFirst 12
Results 16 to 30 of 30

Thread: Breadboard end attached and forgot to elongate holes in tenons

  1. #16
    Join Date
    Feb 2003
    Location
    McKean, PA
    Posts
    15,595
    Blog Entries
    1
    If the center 6" of the bread board ends are glue to the table top. All you need to do is drill out the dowels from either the top or the bottom in the areas of the bread board that is not glued. Once you drill through the tenon of the table stop drilling, leaving the remaining portion of the dowel in place. Then cut shorter dowels and put them in the 3/8" holes so that they do not touch the tongue portion. There is no need to elongate the holes in the tenon. The center portion that is glued will hold the bread board ends on the table and the rest of the table can shrink or expand as it wants to. It will still look like the dowels are doing their function, but they aren't needed.
    Last edited by Lee Schierer; 03-20-2018 at 9:01 PM.
    Lee Schierer
    USNA '71
    Go Navy!

    My advice, comments and suggestions are free, but it costs money to run the site. If you found something of value here please give a little something back by becoming a contributor! Please Contribute

  2. #17
    I like this idea.

  3. #18
    Join Date
    Dec 2010
    Location
    WNY
    Posts
    9,648
    No disrespect, but I think the old guys used dowels in elongated slots for a reason.

    John

  4. #19
    Join Date
    Nov 2016
    Location
    Kamiah, ID
    Posts
    280
    Quote Originally Posted by Pat Barry View Post
    I would look at drilling out the dowels, then, from the bottom side, use a router to make a relief hole, lets say 1/2 inch dia just deep enough to get to the crossgrain boards. Then, make your elongated holes, from the bottom. After that make some plugs to fit into the routed holes on the bottom breadboard. Then, drill your dowel holes from the top and install your dowels. Its a bit of work but would give you a clean top side and the elongated dowel holes you need
    Answers like this are why I read this forum. What a great idea!

  5. #20
    BD883A5D-6A74-4799-A08D-49B712517238.jpgFirst — thanks everyone for the excellent input and support. I love the suggestion of elongating from below — but I failed to describe my breadboard ends. Not sure if picture will show...but my “breadboard ends” are 5.25” thick. I know, I know — what in the world was I thinking.....anyway, thanks again all!

  6. #21
    Join Date
    Apr 2017
    Location
    Michigan
    Posts
    2,758
    With the center glued you only need to get to the dowels in the outer 16" or so on each end. These dowels can be replaced with ones stepped smaller in the tenon area.

  7. #22
    Join Date
    Dec 2010
    Location
    WNY
    Posts
    9,648
    Quote Originally Posted by Tom Bender View Post
    With the center glued you only need to get to the dowels in the outer 16" or so on each end. These dowels can be replaced with ones stepped smaller in the tenon area.
    If enough of the dowels can be cut away for that work, and still have enough meat left for it to do it's job, that is a brilliant solution! If the dowels are 1/2" you'd likely have to cut away 1/4" on the very outboard ones.

    Let's see. 48" of QS white oak with a radial shrinkage of 5.6% per Hoadley. If it's at 35% RH now and will go to 75% in the Summer, the EMC will go from around 6.6 to 14%, sounds extreme but let's use it.

    From Hoadley: Delta D = Do x S x (Delta MC/fsp), where Do = initial dimension, S = Shrinkage from Table 6.2, MC = moisture content, and fsp = fiber saturation point


    Plugging in some values: Delta D = 48" x 0.056 x ((0.14 - 0.066)/0.28) = 0.71" Ouch. Even if this is vastly overstating how much that top is going to move, it's still going to be a lot, and likely more than the dowels are going to be able to handle by cutting steps in them. The expansion will be 1/2 the amount on each side of center, but that's still 0.35". But if it only ends up being half of that in reality, well, maybe.

    Whether or not this is an acceptable solution, the calculation shows the top is going to expand a lot if the RH changes that much. Implementing a solution to accommodate that expansion is better done now than dealing with the failure that's almost sure to happen.

    John

  8. #23
    Join Date
    Apr 2011
    Location
    north, OR
    Posts
    1,160
    To expand on Pats idea.. drill out the dowels, cut the slots from the top (because that's what you have) and then make elongated plugs with smaller pin ends that fill the slot in the end but not in the boards (not to hard to turn on a lathe).

  9. #24
    Quote Originally Posted by Joe Dada View Post
    BD883A5D-6A74-4799-A08D-49B712517238.jpgFirst — thanks everyone for the excellent input and support. I love the suggestion of elongating from below — but I failed to describe my breadboard ends. Not sure if picture will show...but my “breadboard ends” are 5.25” thick. I know, I know — what in the world was I thinking.....anyway, thanks again all!
    That looks like a lip! Not quite a breadboard. Let me ask...... you have this lip around the entire perimeter of the table top? Mitered in the corners? This lip pictured.....is this piece glue to the entire length of the end of the table?

  10. #25
    Join Date
    Sep 2013
    Location
    Carrollton, Georgia
    Posts
    1,815
    Joe, this is what I had in mind.

    x.JPG

  11. #26

    Lip or breadboard?

    Quote Originally Posted by Bill Orbine View Post
    That looks like a lip! Not quite a breadboard. Let me ask...... you have this lip around the entire perimeter of the table top? Mitered in the corners? This lip pictured.....is this piece glue to the entire length of the end of the table?

    Yes, this “lip” goes around entire perimeter.

    Long “sides” dominoes and glue entire length.

    Short “ends” (which I’m referring to as breadboards) just glued center 6”, and they run width of table field, plus width of sides plus about 0.25” on each side(they stick out now but I’m estimating that they’ll be about even with sides middle of summer (high use time here at “the lake”)

  12. #27
    Thanks again everyone — can’t believe the support and great ideas. I’ve drilled out all but the center dowels and replaced with plugs that don’t extend in far enough to be in way of tenon movement/expansion. If end/breadboard warps or pulls away unacceptably, then I think I will carefully mill it completely away from table and replace with exact replica (after not forgetting to elongate the dowel/pin holes.

    Thanks again all!

  13. #28
    Quote Originally Posted by Joe Dada View Post
    Yes, this “lip” goes around entire perimeter.

    Long “sides” dominoes and glue entire length.

    Short “ends” (which I’m referring to as breadboards) just glued center 6”, and they run width of table field, plus width of sides plus about 0.25” on each side(they stick out now but I’m estimating that they’ll be about even with sides middle of summer (high use time here at “the lake”)
    Sounds like you thought well but forgot the elongation. Me....If this were mine....would take a fein saw (or similar) and cut glued area and dowels (if glued) from underneath to remove this lipped breadboard. Because I have that option. And this is my opinion. There are many more ways about it.

  14. #29
    Join Date
    Apr 2017
    Location
    Michigan
    Posts
    2,758
    Install the other end first so you have the details worked out.

  15. #30
    Join Date
    Sep 2016
    Location
    Modesto, CA, USA
    Posts
    9,884
    You could make the dowels out of metal for extra strength in the turned down area. use epoxy to glue them in.
    Bill D.

Tags for this Thread

Posting Permissions

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