Sand in glue

[David]

Does anyone here use the trick of adding sand to glue to reduce slippage? If you do, is it effective enough for you, or does it barely make a difference? I had such a hard time when gluing up 9 pieces of a lamination, I ended up doing the piece over. The next time, I took each piece to the DP and drilled holes for dowels. The first lamination was gonna get milled and stupid me had used a finish nailer every 3 pieces, forgetting that I'd be running the completed lamination through a dado. Besides which, with the glue causing slippage, each time I squeezed the trigger, the pieces would move slightly. Not a good method.

When a glue-up must not slip is sand not completely up to the task? How about for laminations?

Dave

[Duane Bozarth]

Never even heard of it....can't imagine how one could have anything w/ enough grit to be effective and get the joint to close, nor if the pieces are able to move, what would keep the grit from simply moving as well since it's essentially floating in the glue film...

...

I would make every effort to

a. Make the piece such that final milling is done after glue-up,

b. a. being impossible, create a jig to hold the pieces.

[SonomaProducts.com]

Depending on the form of the piece you could: - Use biscuits - Make the pieces longer than needed and cut of the slipped ends later - Clamp end blocks across the table and drop the pieces in between them - Use less glue and let it dry for a few minutes before putting the pieces together. Probably the best/easiest fix.

I've never heard of using sand. Can't imagine I'd want to introduce anything like that into a joint.

[Unquestionably Confused]

on 6/21/2005 4:31 PM SonomaProducts.com said the following:

Read it here on the rec recently. I believe the trick is to sprinkle just a few grains into the joint. Once the joint closes up those few grain puncture the otherwise smooth surface of the glue joint and prevent movement as the pressure is applied. The plan sounded logical to me when I read it here but will admit that I've not yet tried it.

[Sam]

I agree, cutting a dado through nails is not a good idea. I've never tried cutting one through glued sand, but I have a feeling that might not be a good idea also. Sam

[David]

I agree that for the project I was laminating and dadoing, I wouldn't want sand in the glue. That Freud dado is tres expensive!

Since no one here so far has tried it, when I get a chance I'll glue some scrap with Titebond and sand, and give a brief report.

Dave

Sam wrote:

[bridger]

sand is as big a no-no for saw blades as nails.

[David]

[Duane Bozarth]

[e-mail] wrote: ...

Well, that's stretching it for the subject case...

[Craigd]

Try salt - a tip I found in the "Glue Book" that seems to work great. Craig

[CW]

Never tried it myself but have known several people that use it all the time. Works great according to them. Wouldn't want to plane the joint afterwards though.

[Lew Hodgett]

Do the glue up with say a max of three (3) laminations.

When cured, laminate a max of 3 laminations together which provides a total of 9 layers.

Use epoxy and let cure at least 48-72 hours in the clamps.

Been there, done that.

BTW, forget sand in the glue, does nothing but make a sandy, weak, joint.

Lew

[David]

I was expecting that if sand works, I'd sprinkle it in the middle of the joint away from the edges. I'd only consider it for face gluing where slippage is such a bear. For gluing up panels, I don't have a slippage problem--I'm using biscuits and or cauls.

Dave

CW wrote:

[Mark & Juanita]

If you can get sand (and glue for that matter) to only stay in the middle of the joint, I'd say you have enough control to keep things from slipping. :-)

+--------------------------------------------------------------------------------+ If you're gonna be dumb, you better be tough +--------------------------------------------------------------------------------+

[Andy McArdle]

An alternative method that I use when I've _no_ other choice is to partially drive two or three small brads an inch or so apart in the middle of the joint/work-piece, then using a pair of pliers snip 'em off as close to the surface as possible.

I've found it works well, but I don't recommend it as "common" practice... although you know where they are and can avoid tooling near 'em, no-one can predict what or who will happen to 'em after they've left your hands.

I "discovered" this method when trying to replace a stringer and destroyed a good japanese pull-saw while seperating the joint. I'm lucky it wasn't a power tool, I guess.

- Andy

[Charlie Self]

Good grief! Sand is going to screw up the joint fit and add an abrasive that will screw up later operations...little stuff, like knocking sharpness off any cutting tools used after glue-up. By itself, glue dulls tools. Adding sand...no thanks!

[W. Wells]

[James T. Kirby]

What didn't you like about drilling for dowels? I do this for headplates and the underlying thin veneers on classical guitar heads - it's pretty standard.

JK

[David]

As I wrote that, I thought it sounds like a fussy procedure.

Dave

Mark & Juanita wrote:

[David]

I have plenty of drill bits but the dowel material on hand was slightly smaller than it's marked size and didn't match any standard bits. The closest size I could drill a hole was a bit too large for the dowel, making alignment more sloppy than I wanted. I'm always in search of a fast, fuss-free method to add to my repertoire of ww skills.

James T. Kirby wrote: