End grain gluing.

[Eric]

I have to make an interior window ledge that is 13.5 feet long. I am using Peruvian Walnut, and the longest boards I can find are 9ft. So.. I need to glue the pieces together. I intend to do this by adding two pieces to either end of the main piece. I have never glued end grain to end grain before and wondered if there is anything I should be wary of. I could use Titebond or Gorilla glue, is there any advantage to one over the other?

Other than my biggest issue might be finding bar clamp long enough. I have the Rockler clamps and I am not sure they can be extended or used with longer bars.

Thanks in advance for any comments/advice.

eric.

[Dave Balderstone]

Yep. You should be wary of gluing end grain to end grain. It's an extremely weak joint.

Can you use a scarf or lap joint instead? Or one of those fancy-shmancy interlocking joints? Spline? Dowels?

[dadiOH]

Yes. You should be wary of doing it. Don't. Make a joint with long grain...scarf is easy.

-- dadiOH ____________________________

dadiOH's dandies v3.06... ...a help file of info about MP3s, recording from LP/cassette and tips & tricks on this and that. Get it at

[Robert Bonomi]

(A) simply butting end-grain to end-grain is *not* a good idea. at a minimum, consider using a lap joint, like this:

---------------------+----------- | +---------+ | -----------+---------------------

(B) Any good wood glue will be fine. I don't see any 'need' for the price premium for Gorilla Glue.

(C) there are lots of ways to clamp up things like this that do _not_ require ridiculously long bar clamps. However, if you do insist on applying end-to-end pressure, the solution is 'pipe clamps', e.g. "Pony". use a long enough piece of pipe, and they will clamp "anything". Recommended is multiple lengths of 4' pipe, threaded on _both_ ends. Then you simply use inside-threaded 'sleeves' to join multiple sections to the length required. (the advantage to this is you can disassemble it after use, eliminating the need to store that say, 14' piece of pipe. :)

To clamp such a glue-up without requiring long clamps, first clamp a couple of pieces of scrap stock (one on each side of the piece) a moderate distance back from the joint edge. thusly:

__ __ / | | \ +-+ | | +-+ +-+ | | +-+ ---------------------+----------- | | | | +---------+ | | | | -----------+--------------------- +-+ | | +-+ +-+ | | +-+ \_| |_/ | | | | | |

then, put clamps across those 'scrap' blocks, thusly:

+-------------------------------+------- \+-+ +-+/ +-+ +-+ ---------------------+----------- | +---------+ | -----------+--------------------- +-+ +-+ /+-+ +-+\ +-------------------------------+-------

It is important to get equal tensioning on both sides of the board. otherwise you will introduce warping.

Note: you can cross-clamp _on_ the joint as well, to help hold it flat, or by using a reverse taper on the edges, you can make the joint 'self locking', as follows:

+-------------------------------+------- \+-+ +-+/ +-+ +-+ -------------------+------------- \ +---------+ \ -------------+------------------- +-+ +-+ /+-+ +-+\ +-------------------------------+-------

[Odinn]

Finger, dowel, half lap, spline, anything except a straight end grain butt joint. As for the clamping, clamp the board on either side of the joint with a small clamp, then run a pipe clamp from the clamp on one side of the joint to the clamp on the other side of the joint.

My ascii art ain't too good, maybe you can make sense from it.

|-------------------|-- (pipe clamp)

------|-------+---------|------ | (joint) | ^ ^ (clamp) (clamp)

[Odinn]

Your ASCII art is much better than mine :)

[D. J. MCBRIDE]

Biscuits?

[Robert Bonomi]

[[.. munch ..]]

Well, _no_wonder_ you're having problems -- for a question, you ASCII it. when responding, you ANSI it.

As in "ASCII simple question, get a simple ANSI." *GRIN*

Secrets: 1) use a fixed-pitch font when composing (on MS-Windows "fixedsys" is a good choice.) 2) make sure that there are no {TAB] characters in what you send. 3) go _big_ -- you need one row/column to show an 'edge', plus a minimum of one row/column for any 'interior' space

see for what a really talented ASCII artist can do. The rest of is worth checking out, as well.

P.S. It'd help if you put your ROT13'd address in your sig. most newsreaders that underestand ROT13 dont apply it to the headers. And it's too d*mn much trouble to do manually.

[Roy Smith]

Would somebody please defenistrate that man?

[Robert Bonomi]

Everybody knows my sense of humor is indefenistrable. Just one of the reasons I do USENET from a UNIX box, not some MS-inspired boondoggle.

However, _that_ remark is by no means original to me.

Then there was the wife of one of my systems-programmer cohorts, who picked up what she _thought_ was some of his vocabulary, and reported -- some years ago now -- that at her place of work, they were getting PCs, to replace all those "dumb-ass key terminals" that they'd been using. He had a *LOT* of explaining to do, when he collapsed from uncontrollable giggles/laughter.

[Odinn]

GROAN :) Sorry, been hearing that for 20+ years (I've been working in the computer industry for 23 years now).

I'm well aware of how to do ASCII art, I'm just a terrible artist :)

Good idea.

[Odinn]

I only use MS because of the garbage I'm required to do at work. I'm the lead admin where I work, 12 remote offices, 500+ UNIX and Windows servers. Some of the apps we've purchased just won't run on UNIX, including some of the web app stuff. At home, I have FreeBSD, Solaris, and AIX server/workstations, wife and daughter have windows laptops.

Hehehe, good one, I'll have to remember that one.

[Patriarch]

"D. J. MCBRIDE" wrote in news:T4Rhe.95196$h6.46625 @tornado.texas.rr.com:

End-on-end dovetails, like they always demo at the woodshows, but which seldom appear in the wild.

An excuse for a new, expensive tool or two.

In my shop: Lap joint.

Patriarch

[Eric]

Thank-you to all who responded. Biscuits I can do, laps also , so I'll do one of those rather than end-to-end. Thanks also for the clamping ideas.

[Edwin Pawlowski]

I have this visual of it. Dovetail fixtures are always shown bench mounted and the piece getting the tails is vertical. I can see this 13' tower with a fixture on top and a guy standing on a ladder with the router. No, you can't change it because Norm always has the board vertical so that is the only way.

[WillR]

There _might_ be a need for a "stretchy" glue -- say the type you use for lamination if there is a lot of expansion and contraction cycles in that window. (Hot sunny days, cool nights etc.) And Gorilla Glue is that stretchy type for laminations. Other than that... And of course some glues are more heat resistant than others.

I know Lee Valley has some good explanations of glues on their sites.

Also See Fine Woodworking April,2005 #176 page 42.

A minor issue in an otherwise great explanation. IMO

[Lawrence Wasserman]

Perhaps with your framing strength will not be an issue, but If I were doing it, I would either use a scarf or half-lap joint, either one would be plenty strong and eliminate concern of weak eng grain glue up.

[Patriarch]

"Edwin Pawlowski" wrote in news:4u_he.327$ [e-mail]:

You couldn't put the tails on the short pieces? ;-)

OTOH, I have a very tall ladder.

Patriarch

[Robert Bonomi]

[[.. munch ..]]

With both pieces made of the same species, and the grain running the _same_ direction, both pieces will move identically. Whereupon glue 'stretchiness' becomes a non-issue.

[Leon]

You should cut a taper/scarf joint and glue the 2 pieces together using the edge grain. Secondly, are you sure you want to use a wood that is that soft for that location?