Replies

1. 
   Dave45 | Dec 25, 2005 06:04pm | #1

   First of all, I wouldn't try to join two short pieces to make a long one.  The seam will always be visible.

   If you've had the wood stored in the room, it's probably good as far as temperature/humidity issues.

1. 
   saulgood | Dec 25, 2005 07:50pm | #2

   Dave, thanks for the input on the humidity.
   No, I wasn't planning to butt two lengths end to end, rather I will be spline jointing them side by side to make a 9" wide board. I'm wondering still what thought I should put into the annulars (up, down, varied?) and whether or not I should attempt to relieve pressure on the back with saw kerfs, or just seal all sides. The wood is very flat and straight, so far.
   Oh yeah, and wondering about fastening (Glue, slotted screw holes, etc.).
   thanks again for the quick response.

2. 
   bobJackson | Dec 25, 2005 08:25pm | #3

   Hello Saulgood:  I have had good results by reversing the annular rings (up-down-up) and keeping the rips that make up the whole glue up narrow. Say 4" or so. With a 9" wide mantle 2 pieces would be ok. The next thing I would do is devise some way of holding down the mantle without restricting expansion and contraction. I dont know what your design is, but a few ideas could be table top clips, or wooden clips, a oversized hole for a screw that will allow the top to slide with movement. Maybe a sliding dovetail if you want fancy. the important part is to hold flat and still move. You probably have some sort of corbells or fireplace surround  to mount to . You could fasten the back side down tight and then the front has the sliding feature. maybe hide the clips with moulding?    Merry Christmas  Bob

1. 
   saulgood | Dec 26, 2005 03:45am | #6

   Bob,
   the build up so far is ####solid flat plane made from spare trex decking, surrounded by a 3/4" by 3 -1/2" "skirt" which will support the outer edge of the mantle (cantelievered 2"). At the top of the skirt will be built-up transition molding (cove, more or less) so I could hide some hardware within the top inch. But that only takes care of the front. For a sliding dovetail (I assume you mean front to back) were you
   picturing TWO individual sets of rails/slots, placed near the ends? I guess I would just route the underside of the mantel, and somehow align the cleats before screwing them down. Do I understand correctly?
   thanks

1. 
   bobJackson | Dec 26, 2005 08:57am | #8

   I am not real sure I understand you either. A fireplace mantle by its nature goes over the fireplace opening. You would either have 2 corbells (left and right of the firebox) or 2 pilasters flanking the opening. The mantle will either affix to the corbells or the pilasters, as I see it.    merry Christmas   Bob 

1. 
   saulgood | Dec 26, 2005 11:27pm | #10

   Bob,
   This "fireplace" is a gas insert - there was no actual fireplace or chimney to begin with. The plane of the fireplace's face protrudes from the original wall about 7" further than that of the "chimney" (vent soffitt) above the insert. The resulting shelf is 60" long by 7" deep at about 5 feet off the floor. My new question is how best to attatch the glued up slab (64" x 9" with overhangs) to the horizontal surface that's there. If I used a sliding dovetail approach, for instance, I guess I'd use two or three 6" cleats spaced evenly across the width (right to left) with corresponding dovetail grooves routed in the underside perpendicular to the length (R to L) to hold it down. I could hide small angle irons behind some molding in the front to keep the whole thing from sliding in and out. Does this make sense? Sorry, I don't have the know -how at this point to post pics.

   Edited 12/26/2005 3:32 pm ET by saulgood

3. 
   JohnH | Dec 25, 2005 08:53pm | #4

   I have edge-glued walnut, both 1/4" and 3/16" thickness, into panels three and four boards wide, with excellent trueness about a dozen times. Since you are starting with a billet, you are one step to the good. Lay a pair of boards edge-to-edge so the grain pattern is a book match. This makes all the stress patterns in the pair to be opposite to one another. If you don't have a book-match pair, choose boards that have opposite ring pattern, warp, twist, or other patterns. Joint or sand the gluing edges so they are true; less than 1/64" gap anywhere along the length. This is important!

   Use any of the standard methods to clamp the gluing edges. I use Lee Valley Cabinetmaker's Glue 2002 GF because it has a longer time to that fatal grab. At first, the clamps are tightened just enough to get glue squeeze-out. Then I wipe it off and push the board faces flush with each other all along the seam. If the boards have a warp along the seam, it is in the opposite direction and when glued, the pair is straighter than either board alone. If you can, have a pair of straight boards with glue-resistant finish laid lengthwise along both sides of the seam, . Clamp this sandwich in the direction perpendicular to the edge clamps. This also tends to make the seam smooth and the pair lay flat. Finally I tighten the clamps. It works best if you work FAST and tighten the clamps in small steps in a sequence. There will be glue squeeze-out because the seam is not accessible while the glue is curing (I wait several hours before releasing the clamps because I dread having a stressed seam open up on me). I remove the squeeze-out with a random orbital sander and the Norton 3X disks from Lee Valley that don't clog up so fast with the cured glue. Final orbital sanding is with 220 grit, followed by hand sanding along the grain with 220 grit.

   Properly done, the only way you can see the seam is by the interruption in grain pattern across it.

1. 
   saulgood | Dec 26, 2005 03:50am | #7

   Thanks john for that excellent post. My clamp collection is a little motley, but I have a good assortment of bar clamps & pipe clamps to do the job. I think I'll use titebond II because that's what I've got a lot of.

1. 
   JohnH | Dec 26, 2005 06:01pm | #9

   Hi Saul,

   Take it from my experience, trying to do precision edge-gluing with bar clamps is an exercise in frustration. By the time you get all the wiggly clamp parts in position, the glue has hit its tack condition ( I call it grab, because it's a more accurate word). The way I justify purchases of better tools and materials is this: I'm going to be looking at this completed project for the rest of my life. Do I want it to say "Good job!" or "What a kluge!" ? Parallel jaw clamps for edge gluing are an excellent investment. They let you do quick and accurate work. You have to use them once to really understand.

   Also, it is really helpful to make a test piece of the same size and shape from scrap. You get all of your clamps set for the right opening and position. And you learn just how fast you need to work.

   Good luck,

   John

1. 
   saulgood | Dec 26, 2005 11:44pm | #11

   John,
   I hear you about the clamps. But in this case, I'm just edge gluing two boards, five feet long by inch and a quarter thick. With a slightly "sprung" joint, I'm thinking that 3 or 4 clamps should do it. I also have the Titebond slow setting glue which
   works well for complicated glue ups, but I'm not sure I'll need it this time.

1. 
   JohnH | Dec 27, 2005 01:18am | #12

   Saul,

   Let us know how it turns out. Even better, post a picture with a close up of the seam.

   John

4. 
   WillGeorge | Dec 25, 2005 09:40pm | #5

   I could really use some good advice.

   That leaves me out!

   Happy Holidays to you TOO! Or Merry Christmas.. Whatever

   If a mantel... I'd go with the best grain match for the top..

   9 inch width should not be to much of a problem.. Should not to be taken lightly!

   If it were me.. Yes I would... Tie the underside down with some angle iron and screws... Guess they would be hidden? Not sure the style of mantle you are making...

   If just a slab... Cut a groove on the underside for some thick Iron and hide with whatever comes to mind that fits your needs..

   Anyway.. I have sticks warp/cup.. everything! No madder how I glued it up! The sticks hardly think of 'YOU' when thirsty or 'Dry as a Bone'...

   GOOD LUCK.. If you have the skill and tools a sliding dovetail across the with and some nice straight grained stick would do nicely...

5. 
   bldrbill | Dec 27, 2005 02:42am | #13

   Edge glueing two 4-1/2 inch wide boards might be a little iffy as far as staying flat.  I edge glue red oak all the time and have no problems as long as the strips are no wider than 3 or 3-1/2 inches.  I believe I would rip the 4-1/2 inch strips in half and then glue the whole thing up in four strips rather than two.  I have tried various orientations of the annual rings and don't think it makes much difference.  Go for the best grain appearance on the top side and don't worry about the rest.  Another important thing is to finish both sides the same.  This includes sanding, staining, finish coats, etc. the same on both sides.  This will prevent unequal moisture absorption and that is the cause of cupping.  Unless your lumber still has a high moisture content, everything should be OK.  Good Luck!!

1. 
   SteveSchoene | Dec 29, 2005 12:16am | #14

   How can ripping a board, and regluing it together with the same grain orientation have any impact on warping.  It just adds a glue line to look ugly.  I use 12", 16" or even 20" boards regularly.  It is more important to ensure moisture content of wood is both low and evenly distributed. 

1. 
   bldrbill | Dec 29, 2005 05:05am | #15

   It has just been my experience that glued up strips stay flatter than wide boards.  I'm not sure why, maybe because the glue line is stronger that the wood.  BTW, if you can work 12-16-20 inch wide red oak and keep it flat long-term, my hat's off to you.  That's something that's escaped me in 40+ years as a professional cabinetmaker.

1. 
   SteveSchoene | Dec 29, 2005 08:23pm | #16

   I should have said walnut and mahogany--quite a bit easier than red oak.  However, I still can't see much value in ripping 4 1/2" boards.  It can't help but make the piece look chopped up and cheap.  Now my interests do call for me to take it to the extreme since I mostly do reproductions of 18th century furniture, where just about everything should be made of single boards for the full width. 

   It is important to avoid the pith and the couple of inches around it--the juvenile wood.  You do have to pay attention with wider boards in that respect, but for the ordinary 6" to 9"  boards shouldn't be much of a problem to find appropriate boards that don't need to be ripped to be stable.