How to glue up a 144"' x 24"' counter top

[Chris Atzinger]

Hi,

I have 6/4 maple boards about 6" wide, that I intend to glue up into a counter top for some built-ins. The end result will be a piece nearly 12' long and 24" wide. I can beg, borrow, and steal enough clamps, I think, but I am unsure of the type of glue to use and how to approach it.

Should I use wood glue, and just glue up 1 board at a time, to keep everything lined up? Should I use a slow setting epoxy like West Systems, and try to get it all glued up and aligned in one shot? I'll have at least 1 person to help. Should I use biscuits?

Is there a better way I am not thinking of?

Thanks!
Chris

[Michael W. Clark]

I would use some type of alignment aid, either biscuits, splines, t/g, dominos, etc. If the bottom is not going to be seen, you could also consider biscuits and pocket screws. I would probably still glue it and only count on the pocket screws as clamps. You could place your clamps temporarily while you screw the boards together. Although pocket screws by themselves may do just fine?

[ray hampton]

the biscuits will keep the boards LINE UP, grain up on one board ,down on the next board

[Jim Neeley]

+1 on Michael's post.

Be sure to account for the seasonal wood movement on this counter top when it comest to affixing it to it's base. I would use epoxy for it's combination or waterproof and gap-filling ability (even though you'll plane the faces true or slightly concave). I would also use a spline for alignment. If the idea doesn't bother you, I'd use pocket holes as clamps and to prevent long-term creep at the joint.

Yes, this is a "belt *and* suspenders approach but, if it was me I'd only want to do this once and *know* it'd be good for the life of the house. To qualify my opinion, I only do work for myself or a friend, not commercially, so the cost of materials and time are not key or part of my financial survival.

If you don't use screws but only use splines, I recommend using fairly tightly fit full length splines (I'd use narrow strips of 1/4" baltic birch plywood). I'd glue the splines into one half of each joint of each board first and let it dry and then assemble the bench in a second, single glue-up process. If you are very careful to ensure your blards are flat and square on all sides, the top should glue up almost perfectly level. A few light passes with a very-sharp hand plane and you'll be ready to finish.

But then, that's just my $0.02!!!

[Mike Cutler]

Chris

You have a few elements to consider;
First I would definitely utilize some form of alignment aid with the pieces.
Second you need to ensure that the piece is glued and clamped in a flat plane, or the twist in the final surface will be evident from end to end.
When you prepare your glue edges as Ray indicated run the boards through the tablesaw, or jointer in the orientation they will be glued up. This will minimize any coopering that may occur due to angular errors of the tablesaw blade, or jointer knives.
I would glue it up as a single panel using either epoxy, hide glue, or Titebond Extend. My preference is epoxy, but that's because I always have it on hand, and have a lot of experience with it. Traditional glues will work just as well as epoxy, but use whatever you are most comfortable with, unless the final surface will see water. If it's going to get wet, epoxy is your better choice.

In a shameless push for epoxy, and having done large panel glueups with epoxy, I will tell you that the weight of the material alone will adhere them. A large epoxy glue up is facilitated in an perpindicular plane where the members are stacked on edge. It's very easy to erect and align a gluing rack with an 8' level, and a string level, along a wall. Any twisting is tuned out. The downside of epoxy is that it's pretty messy to clean up,( don't go for the squeeze out effect!) and no matter what is printed in their literature, epoxy does not reach full cure for a few days, to a week. You are looking at at least 24 hours before you disturb the joints once they begin to cure. I wouldn't begin to prepare edges for at least another 24 hours.

[Tom Fischer]

Here's a window seat I made last year, one glue-up.
150"X 22"
3/4 " Black Walnut top.
About 25 biscuits in the glue up.
I used Titebond Extend (longer setup)
Woodcraft stocks it.
About 10 Pipe clamps.
**
Practice the whole glue up first with no glue.
Make sure all the boards fit easily. No pushing, no cupping.

http://farm9.staticflickr.com/8029/7983454529_ac2ab46e17_b.jpg
http://farm9.staticflickr.com/8448/7983458846_8bb222b660_b.jpg

[Paul Murphy]

One more option is wedge-tongue-and-groove profile bits. You can even run them in a router with a fence attached. Stickley was using them for high end dining tabletops at the time I visited a gallery a few years ago, and had literature praising their alignment value. Because of the wedge, the joint will absolutely go together as it is cut. On the Stickley table you could see the joint profile at the table ends, but it looked fine to my eye.

Just me, but I would probably glue up two boards at a time using a slower set glue such as Titebond II-extend, Unibond-800, liquid hide, or even Titebond polyurethane glue. I don't like to be rushed, and with Titebond II-extend you can glue another board in after about an hour. You could be done in ~3 hours without any frenzy using the Titebond II-extend.
http://routerbitworld.com/Wedge-Tongue-Groove-Bits-s/295.htm

Just my experience, but biscuits are not that precise an alignment aid. I made my first dining table using biscuits, and still had about +1/32" joint mismatch. After that I skipped the biscuits, aligned my boards carefully during clamp-up, and had much less cleanup with planes and scrapers.

[Kent A Bathurst]

In my role as contrarian:

1. I would use std PVA glue. Mainly because I have very limited experience with anything else. But - it will certainly do the job.
2. I would glue up one joint at a time. One board to one board. Then that assembly to one board.
3. The last glue up would be two equal [roughly] halves.
4. The only alignment aid I use are solid cauls and a lot of clamps. Mike H. posted a tutorial on making cauls some time ago. Mine are different, but the general approach is the same. With good cauls, a solid clamping system, and "one joint at a time" I virtually never need more than a card scraper to level out the seams.
5. I don't like biscuits. This is a personal thing, and I have zero argument with those that like them. I found, in my early days, that they did not do what I was hoping they swould do, and that, at the end of the day, it was the pilot that flew it into the hill, not the tools. So I learned how to properly use clamps and cauls.

And - BTW - I have a 30" x 14' HM top on my back bench. That was my first shot with the process I described. It's great, if I do say so myself. But - any criticism about some whacko that would use 8/4 HM for a 14' shop bench top is certainly on target.

[Sam Murdoch]

Kent - do you joint all the boards first or just as you prepare to mate each groups of assembled boards? How do you pad the edges so as not to get clamp hollows (or even shadows of clamp hollows) along your edges. Your method certainly would take some of the "panic" away that sometimes occurs on a big glue up - but then you are doing glue up for 2 or 3 days running on the same project aren't you? Just wondering - not challenging.

[Frank Drew]

Chris,

Absolutely get one or two helpers for glue up day, and do a dry run so that everyone knows what to do and what to expect. This isn't a terribly complicated glue up, and can be done all in one go, but the length of the boards can make it awkward. I agree that some sort of edge alignment aid can help keeping the panel flat across the top, although it's added work at the front end; I'd probably go with biscuits rather than full length splines because those splines would show at the ends (if that will be an issue), and because biscuits go into their slots a bit easier than splines, IMO. Get all the clamps you can, and alternate them above and below the work to even out the pull. Have them all ready to go, opened to length and where they belong, before you apply any glue.



Second you need to ensure that the piece is glued and clamped in a flat plane, or the twist in the final surface will be evident from end to end.

This is essential, definitely prepare a flat, straight layout table of other glue up surface, with all supports or bottom clamps co-planar and parallel, etc.


When you prepare your glue edges as Ray indicated run the boards through the tablesaw, or jointer in the orientation they will be glued up. This will minimize any coopering that may occur due to angular errors of the tablesaw blade, or jointer knives. What Mike means is that for the two edges of each joint, one board's edge should be run on the jointer with the board's face in to the jointer fence, and the mating board face out. Ray, on the other hand, and if I understood him correctly, suggests alternating inner and outer faces of the boards for layup (smiley, frowny as seen from the ends); I don't favor that orientation since it makes the light reflection on the finished panel uneven, but it's a popular technique.

You haven't mentioned the application, but for a countertop that won't see much moisture or abuse I'd probably use white or yellow glue or maybe brown glue (Plastic Resin Glue) for the longer open time and greater moisture and creep resistance.

If you're lucky with your material's yield, you'll be able to get by with only four boards to add up to your desired width; fewer equals easier, and, of course, looks better.

[Kent A Bathurst]

Kent - do you joint all the boards first or just as you prepare to mate each groups of assembled boards? How do you pad the edges so as not to get clamp hollows (or even shadows of clamp hollows) along your edges. Your method certainly would take some of the "panic" away that sometimes occurs on a big glue up - but then you are doing glue up for 2 or 3 days running on the same project aren't you? Just wondering - not challenging.

Sam.....I will try to answer you - if I misunderstood, please nudge me back on line. If I am getting too detailed, then I apologize in advance..........

1. I joint all the boards first. They are jointed, ripped to width, jointed to remove the rip saw marks, and laid out on the table. I jigger them around until I get the grain alignment where I want it, then draw the traditional white-chalk triangle across them all.
2. I take each adjacent pair, and "fold" them together, and then make one last shallow pass on the jointer with those two boards in that orientation. If the jointer fence is out of vertical, this method insures them mate properly.
3. Clamp + glue the first pair.
4. 45 minuets +/-, I pull the clamps, and use a dedicated card scraper to pop the rubbery glue line. Glue and clamp that set to the next board.\
5. Keep going to the middle of the panel, then start from the opposite outer edge, and do it again.
6. I end up with two half-width panels. I'd guess that 50% of the time, the clamping process has pulled things out of line by this point, so I have to do another bookmatched jointing as described above. This can get a bit hairy, on long, wide, sections. There was one galactic-sized pucker factor on a recent 43" x 86" 5/4 QSWO table top. I freely confess that. Came out okey-dokey, but there were any number of deep breaths before I ran those suckers across the jointer. IIRC, there also was one stiff shot of Dalwhinnie as well. If there wasn't, there should have been.

It doesn't take a couple days. 45 - 60 minutes is plenty per glue line. But - you have to be careful because it is what I'll call "fixed" but not at "full cure" after that time. I have never had a problem , though.

One other thing - and this is wildly redundant, so I apologize - but through all of this stuff, none of the boards [B]ever lay flat on anything for any time. Some guys sticker them. Some guys stand them up on end. Me - I stand them up on edge.

On padding the edges - again, I am a contrarian in these Creek environs. I use 3/4" black pipe pony clamps. No fooling. With the get-'em-anywhere orange pony clamp pads. But - understand, please, that my clamping system of cauls, etc., is designed specifically for these clamps, and I always line them up alternating up-down-up-down, and have the cranks alternating front-back-front-back, and the cauls are 8/4 HM that are not gonna let them there clamps do much no matter how I align them, and I reef down on the cauls with some honking Adjustable C-Clamps. I learned the up-down-up-down-to-and-fro lesson the hard way, in the early days - the results were cut up with a TS and a Crapsman circle saw, and rotated 90* and have been my bench top for the last 14 years. So - things sometime turn out the way they should turn out, maybe?

If I missed something, lemme know and I'll try to do better.

If you want photos of my caul + clamping scheme, happy to help there as well.

Regards........................


EDIT: BTW - with all due respect to Frank and others - everyone has a method that works best for them - only twice in 15 years have I had to enlist assistants. I try to simplify things so that is not necessary. Nto that there are no assistants available - there are. Not that I don't like them folks - I do. It is just that I have found that if I need people around to help, on of two things have/will happen: I have not thought it through far enough to simplify the process. And/or - somebody is gonna get lashed with lightning bolts if the slightest thing is out of kilter.............so I keep them out of the line of fire.

[scott vroom]

We did a 12' x 22" desktop a couple of years ago from 5/4 QSWO. Our steps:

1. Jointed/planed four 13' boards, approximately 6-7" wide
2. Did 2 glue ups, 2 boards each. Used a few biscuits for rough alignment, then lots of clamps/cauls. Used TB extended open time glue.
3. Planed/jointed each of the 2-board glue ups, then glued those panels together.
4. Sanded/finished in the shop then hauled it to the job site and screwed it (from below) onto the 2 base cabs we had made earlier. We pre drilled oversized holes in the cabinet tops and used large washers to allow for movement.

If you're securing the panel at all 4 corners you don't need to worry about the panel being a bit out of flat. Screwing it down will flatten it. The main thing is preventing cupping during glue up....use LOTS of cauls.

Here's a few pics

[Sam Murdoch]

Sam.....I will try to answer you - if I misunderstood, please nudge me back on line. If I am getting too detailed, then I apologize in advance..........

Thanks Kent - got it!

EDIT: BTW - with all due respect to Frank and others - everyone has a method that works best for them - only twice in 15 years have I had to enlist assistants. I try to simplify things so that is not necessary. Nto that there are no assistants available - there are. Not that I don't like them folks - I do. It is just that I have found that if I need people around to help, on of two things have/will happen: I have not thought it through far enough to simplify the process. And/or - somebody is gonna get lashed with lightning bolts if the slightest thing is out of kilter.............so I keep them out of the line of fire.

This is funny :D

Me? I use dominos for alignment, cauls if needed, and Bessey K bodies. Most of the time that is good enough. Other times - well that's another post.

[Kent A Bathurst]

Scott...........

I'll see you and raise you. 43" x 86" 5/4 QSWO dining table with - ultimately - breadboard ends................ Whadja use for the finish schedule on yours, if I might ask?

My 2 x 2 HM cauls are 32" long. Tapered from the center to the ends so the clamps pull them flat, with the pressure centered on the glue line - where I have a groove for the squeeze out to ride.

On this 43" wide dining table top, those cauls were not long enough for the final, center joint. Did not want to make new cauls for a one-off. Did not want to buy deeper-throat C-clamps for a one-off. So - I bought a bunch of 2 x 3 BORG wood, to make secondary cauls, if that's what they are called [insert rimshot here :D ].

The dude in the background is the husband of the client. I needed some help on this sucker.


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[Jerry Thompson]

I am all for cauls. They keep it all even and tight. You can make them once and have them forever. I also use liquid hide glue as it has no creep and cleans up easily. I did have a problem of over tightening the clamps one a ended up with a "starved joint."
Good luck.

[scott vroom]

Looks like you're building a boat there, Kent...lol.

It's been awhile but I believe we finished that desk top with GF Seal-A-Cell, then GF Dark Walnut Gel Stain (to pop the grain), then 3 coats Arm-R Seal Satin sprayed, sanding once before the 3rd coat. It was purdy.

[Jim Matthews]

I know I'm coming late to the party -

I'm unsure if the OP is a builder, or homeowner.
If you're a homeowner - have you checked to make certain you can manipulate something this large from your shop to the destination?
I know of at least one boat builder that found his Greenland style kayak could not be removed from the basement, after it was built.

I would glue these all at once, at the place they will be installed.
I would first build a torsion box base for assembly (which can be reclaimed) that was verified flat and level.

The torsion box should be large enough to hold the works, with some overhang.

Glue up with Titebond III in a wet environment.

I would not use clamps, I would use sliding wedges (http://www.descendingashtray.com/archives/349) - with one side screwed into the torsion box top.
Cauls could be screwed directly over the panels, into the torsion box top.



If you set the torsion box top at the same height as your cabinets, you could just slide the finished lamination into place.

jim
wpt, ma

[Chris Atzinger]

Hi Everyone,

Thanks for the responses. Here some answers:

-I am a home owner, with a reasonably equipped shop full of the usual tools. I can't imagine running these 12' boards through my 6" joiner. I have a glue line rip blade on my table saw, but that is really intended for material <1". this is 6/4, so I should probably look for a better suited rip blade.

-The room this is going into is used every day (it's my home office, and I work from home), so building it in place is not ideal for my home life, but I am 99% sure I can get it in through the double french doors, or at the very least it is a straight shot through a window.

-I have made my own cauls before, but never quite satisfied. The last ones, I cut a t-slot in the back, so that they would hold the f-clamps in place while I ran around the glue-up like a maniac trying to tighten things. They served that function beautifully. Unfortunately, I think I took too much material out of them when I cut the slot and they weren't stiff enough (pic below). What is a good radius to put on these cauls?

-Tom/Scott, the window seat and desk look great. This project is actually very similar to the desk. It will be sitting on top of 4 base cabinets and have 4 bookshelf units on top of it. I am not putting breadboard ends on it. I don't think...

Thanks for all of the help!
Chris

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[Peter Quinn]

Always remember you are not milling parts for the space shuttle. Close alignment is important if you are flattening by hand to avoid excessive sanding. I suggest not doing that. Find a cabinet shop with a wide belt you can rent time on, leave it a bit thick, glue it in one shot with titebond III and a bunch of clamps, use some good cauls to keep it flat. Do not align "one up one down", that makes a mess. Most important is best face up, next is crown up. If you are focused you could glue up two tops that size and still be within the open time of type III.

[Kent A Bathurst]

Chris.....

Again - Mike H has a good tutorial on how he made his cauls, out of 2 x 4.

My approach, which has served me very well for 12+ years on the one set:

8/4 HM. I used a pen to mark off the 2" in the center of a blank.

Then - I taped a dime to one end, lowered the blank onto the jointer [with the dime on the outfeed table, obviously] and made some passes across the jointer, until the cutterhead had tapered it right up to the outside of my 2" center lines.

Pulled that dime, and taped 2 dimes to the newly tapered end, and did the same thing in that direction.

At 32" long, that left me with 2" flat in the center, and 15" on each end, tapered from zero to one dime = 3/32" +/-.

Then onto the TS with a miter gauge, where I cut 3/8" x 3/8" grooves across the center, to bridge the squeezeout. I do a lot of QSWO, and smooshing glue into theose pores is a nightmare to get out - after 45 - 60 minutes, I can just peel it off with a card scraper.

WIth a caul below and a caul above the target, I can reef on a pair of 6" C-Clamps, and pull the two 8/4 HM cauls flat - which, by my detailed calculations, puts exactly one great big damn lot of pressure right at the glue joint, and keeps the entire surface flat as well. For any high-end stuff, I only do one joint at a time, so I am focusing that pressure right on one joint [and, so I don't have smooshed glue].

And - it works - that 43" x 86" 5/4 QSWO table top was about as dead-nuts flat as one can get, without a factory or a big drum/wide belt sander, at your back. Also - on 90% + of my joints, a fresh card scraper is all I need to remove all traces of the joint.

It has been pointed out that these tapered cauls don't do anything for you in veneering. I don't do that - yet - but it makes sense to me that curved cauls would be needed there. I didn't make these cauls for veneering. I made them so that I would get very high-quality, repeatable, flat glue-ups, because I was in a constant losing battle to do them well.

If I was doing it again today, I'd go more toward 36" - 40" long. And, I'd design the stand height [cradles that support the lower cauls] to accommodate 8" C-Clamps. With thick lumber, the dimensions on my rig work out that I am at the max throat of a 6" C-Clamp. But - to make new cauls and buy new 8" C-Clamps would be way more $$ than I need to throw at a problem that comes up rarely, so I'm not starting over.....just sayin'.

The last trick - I have stands that hold the "underneath" pipe clamps in position, about 1/4" below the lower caul surface.

One final comment - I have never been able to figger out any benefit from the channel in the back of the cauls to accommodate clamp heads. In fact, it would seem to me to reduce the strength of the caul, which is exactly what I don't want to do - I want it to take a lot of force to bring them flat, so I can transfer that force to the target joint.

[Frank Drew]

Get some Bessey or equivalent parallel clamps and you won't need cauls, IMO.

[scott vroom]

Get some Bessey or equivalent parallel clamps and you won't need cauls, IMO.

One advantage of curved cauls is that they can align the boards on a centered glue line.

[Jeff Duncan]

I do mine similar to Peter, just did 3 - 26" x 10'+ white oak tops last week, but tops are not uncommon for me anyway. I joint all the edges and lay them out the way that looks best....if the wood is dried properly I don't worry about which way the cup is going, I just run them so they look good. Once I get them arranged the way I want a use a pencil to draw a triangle on the faces....this ensures I get them back in the right order. I don't use alignment aids as they take much longer to both mill, and more importantly glue and align during the glue-up. I use original Titebond, apply the glue down the length of a board and spread with my finger quickly, flip it down and glue the next one, repeat as necessary then start clamping. For thick tops I use I-beam clamps as they have the ability to pull everything tight....much stronger then standard parallel clamps, (parallel clamps like Bessey's can work, but your joinery better be dead nuts on as they won't give you the oomph to counter any little deviances, I really don't like them on thick hardwood glue-ups), pipe clamps are adequate as well. I do use biscuits for one part though....I place one under each clamp so it doesn't sit directly on the wood;) I also keep a deadblow hammer close by to help tap boards into place as I go. I'll usually start at the middle and work my way towards the ends using both the hammer and leverage of pulling the ends up or down to get everything flat. Cauls....good for wide tops, but you don't really need those either for such a narrow piece if you do everything else correctly;)

There is no magic in making a solid wood top, you just have to be careful and pay attention to what your doing. I also recommend a dry run or two as if your not used to this type of glue-up it will help work the bugs out ahead of time.

good luck,
JeffD