Replies

1. 
   BruceS | Jul 11, 2010 01:49pm | #1

   Biscuits are for Norm

   IMHO,  biscuits are next to worthless.    To prevent  "slippage"  my prefered method is a reversable glue joint bit, getting about 1/3 more glue surface.   And Dominos area great way too.   But freshly jointed edges,  either jointed or planed will be more than strong enough when correctly glued and clamped.     I wouldn't worry too much about the biscuit slots removing too much surface area from a 1.5" thick board.

2. 
   flairwoodworks | Jul 11, 2010 03:32pm | #2

   I agree with Bruce

   Go for it.  You have nothing to worry about as far as strength is concerned.  I like to use dowels when alignment is critical.  If anyone wants, I have a once-used Porter Cable 557 that I don't need!  But I ain't giving it away either.

3. 
   Lataxe | Jul 11, 2010 05:41pm | #3

   Nice biscuit, good biscuit

   JM,

   As others note. edge-glued boards are strong enough without biscuits or even with a few redundant biscuit slots in them.  If you're bothered about the empty slots, glue some biscuits in then cut/plane off the excess that sticks out,

   If one does need a little help in aligning such board-edges, the biscuit joiner is a useful tool - but it does (like any tool) have to meet the precision needed in its application to the wood, both of the machine and it's operator.  If your slots have misaligned the boards then either you or the joiner is at fault.  Unfortunately, the cheaper biscuit joiners seem less than accurate enough, which is why those who use biscuit joiners a lot prefer a Lamello or a Mafell.

   A Festool Domino can perform the alignment task also, should you need a bit of help with those long, heavy boards.  The machine is certainly very accurate; and as easy to use correctly as a good biscuit joiner, since it works in a very similar fashion.

   Other alignment methods, such as the tongue & groove or other routed profile, waste a significant amount off the edge of each plank.  They too can easily get misaligned when being machined  and will therefore misalign the boards. It also takes a lot longer to machine such edge-profiles than making a few biscuit or domino slots. These profiled edges do increase the glue area but , as we know, the area of planed-flat edges is more than enough for modern glue to provide a very strong joint.

   Finally, here is a Very Nice Clamp for gluing up big panels (and small ones): the Plano Press.  It allows panels to be glued-up vertically whilst clamping & aligning the edges; and also keeping the faces flat.  If you do a lot of panel or table-top glue ups and have limited space, a Plano is a great tool to have on the wall of your shed.  Add as many vertical arms as you like and even use bar clamps in between.

   Lataxe

   
4. 
   DonStephan | Jul 11, 2010 08:18pm | #4

   In addition to the excellent responses received, I'd suggest dry stacking the entire set of boards first to see how well the edges meet.  If there is some twist, better to find it during dry stacking.  The end result will be quite heavy and big, so ideally there would be minimal cleanup. 

   After seeing it suggested a couple times, I also dry clamp at each step.  That assures me I have at hand all the clamps I'll need, the cauls are properly spaced, and so on.

   Good luck!

1. 
   Lataxe | Jul 12, 2010 05:10am | #5

   The Mark I Eyeball

   Don,

   You're right to mention the dry stacking procedure as a wise check of board edge alignment.  As well as that possible twist you mention, a dry stacking of the boards also reveals how well the edges meet (e.g. whether any sprung gaps have been correctly formed) and whether the panel is flat (i.e. whether. the edges are all at 90 degrees to the faces).

   I like to place the board-stack vertical, with the bottom board in the bench vise with the rest of the boards free-standing on top of it, edges up/down - as they will be oriented in that Plano Press I pictured.  When the boards are dry-stacked in this vertical way, gravity will reveal any lack of 90 degrees in the edges as the panel will tend to topple one way or another.  If the dry stacked panel will stay upright unassisted, the edges must be at, or near enough to, 90 degrees. 

   It's also easy to see any light shining through the sprung gaps of a vertically-stacked panel, to judge the gap width and to make sure the gap gradually disappears from the middle towards both ends.

   But as a final check of panel flatness, I look down the ends of the dry stacked boards using my splendid eyeball.  This is a very sensitive tool and can detect even small deviations from straightness/flatness in the dry-stacked panel.

   ******

   Incidentally, it does pay to keep the boards in the same order within the panel as when the board edges are first made and these gravity and eyeball checks applied.  I generally use a pencilled-on carpenters triangle to ensure the boards go into the clamps as they were in the dry stack. 

   My procedure for making the board edges flat/square involves matching each edge to it's mate via careful final planing, to make that sprung gap.  In addition, I sometimes use match-planing of two boards at once, which means that the matched edges will meet and form a flat panel even if they are not exactly at 90 degrees.  If the edges so-matched are not kept in their original relationship, the panel might well not dry-stack flat.

   Lataxe

1. 
   PCM | Jul 12, 2010 08:13am | #6

   glue removal

   Lataxe,

   A great picture, worth many thousands of words-I heard that somewhere!

   Seriously, what is your method of removing the glue from the glued up edges?

   I will try the dry stack method, do not use biscuits anymore, and have always had a really bad experience when removing dried glue. 

   Thank you!

   Pete  

1. 
   Lataxe | Jul 12, 2010 09:29am | #7

   Glue gloop removal

   Pete,

   It's all in the timing............

   I use Titebond I or III which, like most PVA glues, will form a strong bond in an hour or three (depending on temperature) even in sprung-jointed boards.  However, the glue squeeze out remains quite soft for a while longer.  Although it racked my nerve at first, I adopted the procedure of extracting and cleaning the glued-up panel from the clamps after about 6 hours (just before bedtime, typically).  The joints have never opened up but the glue squeeze-out is far from rock 'ard and can be easily scraped off without pulling up those small lumps of wood that often pull out when one attempts to scrape off truly hardened glue squeeze-out.

   I use a tungsten carbide bladed paint scraper to take off the glue squeeze out.  The scraper has a handle and a blade only 2 inches long, so can get down into any slight dips or around slight bumps in the panel.  It helps to achieve clean glue removal if the blade is kept very sharp, using a small diamond hone.  The glue comes off much more easily when it is still soft enough to deform slightly when scraped.

   If the glue squeeze out has gone very hard, it's removal becomes more difficult and one must be more careful (less vigorous) with the scraper.  Those glue-runs down the face of the boards are the worst; small beads of hard glue at the joint often ping-off quite cleanly but glue runs seem to get a firm hold of the wood fibres.  This is when you discover that the glue bond really is stronger than the wood fibre bonds, since removal of the glue runs is very prone to pulling up some wood with the glue. 

   If there's any inclination for the glue-run removal scrapes to pull out chunks of wood (I test near the end of the panel, as that is often cut off when forming the final piece) then I resort to a block plane with a finely set A2 blade in it.  The glue will plane off but it does tend to blunt or even nick the blade sometimes.  But glue-planing is possible and allows a controllable if tedious removal of those runs.  The blade edge needs to be remade afterwards though.

   *****

   After making numerous glued up tops and panels one gets better at judging the right amount of glue.  The ideal amount results in an even row of small glue beads along the whole length of the joints when they are clamped up, with no dribbles or runs. Such an even row of small beads is easily removed (pinged off with the scraper) even when the glue has gone very hard.  I do still get the odd dribble (of glue I mean, I yam not yet in the dotage!) but far less than heretofore.  When I first began woodworking there was glue gloop all over the panel - sometimes running not just across one plank but two or more and on to the floor!. 

   Lataxe, not quite so sticky as in yesteryear.

1. 
   jointerman | Jul 12, 2010 12:15pm | #8

   The glue squeeze out was going to be my next question. I often wiped the glue off with a very damp rag, trying to make sure I got it all out instead of smearing it into the wood fibers. Although this usually works, I was always left wondering if it would be better to let the glue set up some and then scrape it. Reading your post, I think that's what I'll do.

   As for the boards, I have dry stacked them, they square and pretty stable. It took me about three weeks to joint, edge, and thickness plane all of these boards since I wanted to let the tension release from the very rough lumber I started with. I also tried to do spring joints on a couple of them. Though the spring looks pretty good (less than 1/32 spring over 7-feet), it's hard to do with boards this long and heavy and without a jointer plane. 

   It's time to start gluing! BTW: I don't think that I'll ever do enough panels to warrant the vertical panel gluing system. This project isn't so technically demanding as nerve racking because of the size of the boards and the cost of the cherry!

2. 
   derekcohen | Jul 13, 2010 10:40am | #10

   I can add two tips.

   The first is, after adding glue (I like Titebond III), I give the boards a little rub, and this forms a nice suction to pull them together.

   The second is I wipe off the glue with wet paper towel immediately after the claps go on. One reason for paper towel is that I want to throw it away - never use any cloth that has come into contact with a blade (such as wiping it), or filings as it will cause the wood to go black. I use a goodly amount of water to ensure that all excess glue is washed away. I've never experienced a problem with the finish.

   Regards from Perth

   Derek

3. 
   PCM | Jul 13, 2010 01:54pm | #13

   question about glue under clamps

   Derek,

   I agree with your point about paper towels, I buy by the 30 roll case for restoration and woodworking.

   How do you handle the glue that is under the clamps?

   Thanks!

   Pete 

4. 
   derekcohen | Jul 13, 2010 10:40am | #11

   I can add two tips.

   The first is, after adding glue (I like Titebond III), I give the boards a little rub, and this forms a nice suction to pull them together.

   The second is I wipe off the glue with wet paper towel immediately after the claps go on. One reason for paper towel is that I want to throw it away - never use any cloth that has come into contact with a blade (such as wiping it), or filings as it will cause the wood to go black. I use a goodly amount of water to ensure that all excess glue is washed away. I've never experienced a problem with the finish.

   Regards from Perth

   Derek

5. 
   PCM | Jul 13, 2010 07:40am | #9

   Lataxe,

   As always, great insight!

   I am going to be making a large dining table soon, and am studying any tips/tricks, etc. about proper glue up and removal.

   In the past I have had good results, and the tops came out nice, but I've always felt my methods were hit or miss, or the luck of the beginner at the poker table.

   thanks!

   Pete 

6. 
   jointerman | Jul 13, 2010 01:40pm | #12

   Large dining room table
   I'm building a large-ish table myself, 90-inches x 45-inches. Last night I glued up the first three boards and clamped them with about 15 Bessey clamps. I let it sit for about 3 hours and then went back out to scrape the drying glue. Although this worked okay, the tough part was not being able to scrape the glue between the boards that were slightly out of alignment across the surface. I am not to worried since I'll be sanding or planing the surface flat, but I think I'll revert to wiping with a wet rag or paper towel for the next sets of boards. Scraping of course will still likely take place.

5. 
   derekcohen | Jul 13, 2010 08:13pm | #14

   How do you handle the glue that is under the clamps?

   Hi Peter

   If it is possible (depends on size, weight) I will loosen a clamp and swab, then replace the clamp. It helps to have many clamps securing the boards.

   Regards from Perth

   Derek

1. 
   PCM | Jul 13, 2010 09:35pm | #15

   removing clamps

   Derek,

   Your method of removing clamps, swabbing, replacing clamps makes sense! I will keep it in mind when I get into this large table top.

   Thank you so much, not only for this post, but for all of your advice in the past.

   Pete