What to do with glue squeeze-out - when should we remove it?
Ask three or more woodworkers the above question and you'll probably get three different answer: right away, after a few minutes and after the glue had dried. Chances are equally good that the person who gives you any of the three answers will have a rationale that seems plausible. In short, the subject of glue squeeze-out is one that's sure to generate some good discussion among anyone who has worked with wood.
Whenever you clamp two pieces of wood together with glue in between, you're dealing with variables in clamping pressure, consistency and amount of glue and species of wood. All of these factors can affect the amount of adhesive that may ooze out of the joint, as well as the technique you use to remove it.
Some Squeeze-out is Good
A little glue squeeze-out — a few tiny droplets or dribbles along the joint — is a sign of a good glue application job. No squeeze-out means you might have applied too little glue, creating a "starved", potentially weak joint. All the experts agree on this point.
Glue squeeze-out becomes a problem only if you can't com¬pletely remove all the excess glue from the wood surface. Any glue that remains on or in the wood fibers can hamper application of finishing material. You know you must remove all the glue that gets squeezed out from the joint, but when and how?
Generally, we don't advise waiting until the glue has dried hard. Note the "generally." Sometimes, you might be able to estimate your glue needs exactly and get just a few tiny beads of glue squeeze-out. If you have no more than this, you can wait till the glue has dried and flick off the beads with any sharp tool.
But, as was mentioned earlier, you could be making a serious mistake in trying to limit glue squeeze-out to so small an amount. Remember the starved joint.
The other extreme is no better. If so much glue oozes out that you'd need a chisel or lots of sand¬paper to remove it after it hardened, you're in trouble. Since the completely dry glue is quite likely harder than the grain of the surrounding wood, the adhesive you cut away might take some wood along with it. And if you use a sander, you risk sanding away too much of the wood.
No Water Is Better
We agree to disagree somewhat with both Snider and Duncan regarding use of a damp sponge or rag. We're convinced that the combination of moisture and pressure can indeed push some glue into the pores of the wood. Sanding will remove the glue at the surface, but perhaps not all the glue that was forced down deep. Why take a chance and wait maybe a couple of days for the wood to reach an equilibrium state before you can sand off the residue?
Let Glue Gel
Clean up excess glue after it has gelled a bit but before it has hardened. Follow Snider's advice and wait 5 to 10 minutes (or longer) after clamping. At this point you'll be able to slice away the "cottage cheese" with a dull chisel or other type of scraper.
Scraping the glue off after it has set for a few minutes makes sense. It's sort of a compromise between removing it right away and waiting until it's completely dry. Of course, once you remove the skin that's formed on the surface of the glue, the glue underneath is still wet. But removing it at this point keeps you from smearing the glue all over quite as much. And by removing as much as you can in this way, you minimize the sanding you'll have to do once the remaining glue has hardened.
How To Avoid Excessive Squeeze-Out
• Check that joint parts fit well by clamping together before gluing. Open pores of wood by sanding.
• Use a brush about the same width as the wood to spread glue. Glue directly from a squeeze bottle should be applied in zig-zag lines to both surfaces, then the pieces rubbed together to distribute.
• It's best to apply glue to both surfaces thinly and allow to par¬tially set before joining pieces.
• Check drying or "set" time of glue you're using. Some set up faster than others. Work to the pace of the glue.
• Don't apply too much clamp pressure. The object is to create a thin film of glue between parts. Too much pressure will squeeze the glue out, resulting in a starved joint. Usually, finger tight will do.
Paste stain and varnish - best way to finish your woodworking project?
No question about it - if you want the toughest possible clear finish on a project, polyurethane varnish is the way to go. It's hard, lustrous, and impervious to alcohol and water. But it is some trouble to apply. You have to mess up a brush, worry about runs and sags - and then there's the dust problem.
Paste varnishes and their companion products, paste stains, avoid all these problems while still giving you all the advantages of a polyurethane finish. I've been seeing them in the woodworking catalogs, and decided to order some to give them a try.
I made up some wood samples - hunks of oak, maple, and pine - and applied the stain and varnish according to the directions. For comparison, I also finished a sample in satin polyurethane - brushed on.
The paste varnish is simple to apply. You just wipe them on with cheesecloth, applying a light, smooth coat. The stains I tested is just as easy. It goes on smoothly and cover evenly. Between coats of varnish, I buffed off the samples with steel wool, then wiped on a second coat.
In our dusty shop, the paste varnishes came out as smooth as a carefully applied brushed-on and hand-rubbed finish. The brushed-on polyurethane, on the other hand, was full of dust.
There was some variation in the degree of yellowing or warm tone the varnish gave to the wood. After the samples were thoroughly dry, I gave each a coat of paste wax. Then, to test them for durability, I dribbled both water and alcohol on all the samples, letting them stand until dry.
This torture test did show up some differences between paste varnish samples and the brushed-on polyurethane. There was some slight discoloration and grain rising on the paste varnish samples, while the brushed-on polyurethane wasn't affected at all.
However, the paste finishes were easy to repair. To patch them, I buffed all with steel wool and applied another coat of wax. I could still see very faint traces of raised grain in all samples after rewaxing, but nothing that couldn't be lived with. All in all, I'd have to rate the paste finishes as being tough and easy to care for.
A distinct advantage of the paste varnishes is that the finish itself is very thin, without much buildup. This gives that hand-rubbed look without all the elbow grease. The cost of the paste varnishes and stains is in the same ballpark with brushed-on varnish, and a little seems to go a long way. Another plus is that paste varnishes and stains are virtually odorless.
My advice - give them a try! I think you'll agree that paste varnish and stain solve a lot of finishing problems.
Oak - one of the best hardwood in woodworking
Brief History of Oak
The Greeks and Romans used oak to construct their seagoing vessels because of its strength, toughness, and durability. The Saxons in England fattened their hogs with acorns, and ground the acorn for use as a seasoning. During this same period, landowners used the acorn as part of their daughters’ doweries.
In Europe, many great halls and castles were paneled with oak wain scoting and almost all furniture there was made of oak.
Today, the oak provide; food, tanbark for tanning leather, dyes, ink, even commercial cork.
Oak Wood Identification
Though there are 14 oak species of commercial importance grown in the U.S., they're marketed either as red oak (Quercus rubra) or white oak (Quercus alba).
Red oak has a pinkish red cast to it, large pores (you can blow smoke through one end of a piece of red oak and it will come out the other), and is quite hard.
White oak, on the other hand, is a tannish brown wood, has smaller pores, and is somewhat harder than red oak.
Woodworking Properties
Uses in Woodworking
Both red and white oak are moderately stable before and after working, and both work well with hand and power tools. Because white oak contains an abundance of tylosis (a membrane that seals cells), it is waterproof. Oak accepts finishes well. With built-up finishes, you may want to use a paste filler to fill the pores. This isn't necessary with oil finishes.
Uses in Woodworking
With these woods, the list goes on and on. You can use them for furniture, flooring, interior trim, paneling, turning, carving, and woodenware. White oak has two other important applications. It's highly prized as a material for making barrels and other watertight vessels, and it's one of the best woods for steam-bending wooden furniture parts.
Cost and Availability
One of the most commonly available of all woods, oak falls into the medium price category, with white oak somewhat higher than red. You can purchase oak in several different forms: lumber, plywood, interior trim, flooring, turning blanks, and veneer.
Source of Supply
Over 50 percent of the oak logged annually comes from the southern states. However, if you can get hold of some that's been grown in the Appalachians or the northern states (it's sold as northern oak), buy it. Because it grows more slowly than southern oak, it has a finer texture, more uniform color, and it works better.
Things to check out as you shop woodworking tools
Chances are you won't actually use the tool before you buy it, but you can learn a lot about it while at the store. Try changing bits. Is it easy to get your wrench on the collet nut or does the bases interfere? Does the collet let go of the bit with a single turn of the wrench, or does it take two or three bites? Does the router have a flat top so you can stand it on its head for bit changes?
Check the switch? Is it easy to reach with your hands on the grips or will you have to let go of the tool to shut it down?
How is your view of the bit? Can you see where it is and where it is going? Check the power cord. Is it stiff and heavy? If so, it can drag and make freehand work difficult. Do you like the feel of the grips? Can you remove the grips if necessary to fit the router into tight spots? Can you remove the base from the router? (You may want to do this to use the motor in certain accessories, or to use it freehand for power woodcarving.)
Finally, does the router maker offer accessories to extend the usefulness of the tool and help it live up to its potential as the most versatile tool in your shop?
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