I got a really good deal on the veneer
I paid $200 for over 300 sq ft of all highly figured veneers
maple
Fiddleback Angre
Bubinga (striped and figured)
Makore
Cherry
and some other very knotty veneer I cant remember the name of.
most of it is in 12-16" wide by 40-60" lengths
gotta love ebay
Ill look for the Tung oil
and your saying to not use the Polyurethane either correct ?
I paid $200 for over 300 sq ft of all highly figured veneers
maple
Fiddleback Angre
Bubinga (striped and figured)
Makore
Cherry
and some other very knotty veneer I cant remember the name of.
most of it is in 12-16" wide by 40-60" lengths
gotta love ebay
Ill look for the Tung oil
and your saying to not use the Polyurethane either correct ?
Oil is for Hobbyists
Stick with the oil -- it produces excellent results -- and more importantly it is much more forgiving of beginners mistakes. You have beautiful veneers -- it would be a shame to ruin them with any of the urethane (Varathane is a trade name), varnish or lacquer finishes. These products are used by production shops that are in a rush to their product out the door...
Behr's Tung Oil Finish only darkens the wood a tiny bit. Linseed Oil is dark brown and it imparts a dark patina to all woods. Any finish will darken the veneers -- even the water based stuff. Do not be tempted to leave the veneer unsealed -- you will be attacked by water sometime. It must be sealed...
Stick with the oil -- it produces excellent results -- and more importantly it is much more forgiving of beginners mistakes. You have beautiful veneers -- it would be a shame to ruin them with any of the urethane (Varathane is a trade name), varnish or lacquer finishes. These products are used by production shops that are in a rush to their product out the door...
Behr's Tung Oil Finish only darkens the wood a tiny bit. Linseed Oil is dark brown and it imparts a dark patina to all woods. Any finish will darken the veneers -- even the water based stuff. Do not be tempted to leave the veneer unsealed -- you will be attacked by water sometime. It must be sealed...
Lucidity said:
This is not normal - I've used waterbased urethane directly on veneer with no bubbling or other ill effects.
This sounds like the glue is not completely adhered. No finish should be applied until you have made sure the veneer is properly attached.
Tapping with your fingernail and listening for a hollow sound will show where the veneer is loose. Heat from a heat gun or clothes iron will reactivate the glue somewhat. Then use a lot of pressure to make it to stick. Slit bubbles open with a razor blade with the grain to relieve the air pocket.
It always makes sense to practice on something other than the finished product, especially if it's your first attempt.
Absorption of moisture would be a good guess, or that whatever finish is being applied contains a solvent that would weaken the glue.
Flattening veneer with veneer softener will help quite a bit if your situation is like the original poster's - the flatter the veneer (and the surface to be veneered), the better the results will be.
If you have more specifics (what glue, what type of veneer, what finish, etc.), someone here can probably give a more detailed answer,
John
Flattening veneer with veneer softener will help quite a bit if your situation is like the original poster's - the flatter the veneer (and the surface to be veneered), the better the results will be.
If you have more specifics (what glue, what type of veneer, what finish, etc.), someone here can probably give a more detailed answer,
John
Absorption of moisture and expansion of the food fibers is one reason.
Contact adhesive attacked by the solvent in the finish is actually a rare occasion. It’s a very common misconception. In order for it to happen, finisher must apply an extremely healthy coat of lacquer. DIY don’t own a spray booth or a spray system in most cases. Consider also that Contact adhesive is used with paper-backed veneer in the majority of situations.
Now the real reason. There’s a variety of different wood coating. Some are saturating the wood or veneer, some sort of laying on the top with minimum absorption.
A good example of penetrating finish is an oil finish, being Walnut, Danish or a Sun flour oil.
Other finishes such as Lacquer, polyurethane or varnish don’t really go through the thickness.
As the wet coat applied and adhesion is taking place, the finish is starting to dry. Solvents are evaporating and as thin as the coat is, it starts shrinking. The shrinkage is extremely small but the surface tension force created is enough to pull the loose veneer.
I know someone here who’s a big fan of contact cement and there’s an old trick to pressing it. Perhaps he could share it.
Contact adhesive attacked by the solvent in the finish is actually a rare occasion. It’s a very common misconception. In order for it to happen, finisher must apply an extremely healthy coat of lacquer. DIY don’t own a spray booth or a spray system in most cases. Consider also that Contact adhesive is used with paper-backed veneer in the majority of situations.
Now the real reason. There’s a variety of different wood coating. Some are saturating the wood or veneer, some sort of laying on the top with minimum absorption.
A good example of penetrating finish is an oil finish, being Walnut, Danish or a Sun flour oil.
Other finishes such as Lacquer, polyurethane or varnish don’t really go through the thickness.
As the wet coat applied and adhesion is taking place, the finish is starting to dry. Solvents are evaporating and as thin as the coat is, it starts shrinking. The shrinkage is extremely small but the surface tension force created is enough to pull the loose veneer.
I know someone here who’s a big fan of contact cement and there’s an old trick to pressing it. Perhaps he could share it.
Re: Oil is for Hobbyists
Quite the inverse...
That is not "why" production shops use lacquers or urethanes. To imply that it is simply to expediate a product is false. A high quality lacquer or urethane finish is very laborious and time consuming.
How much time do you think it takes to do a true piano finish?
Production shops use the finishes you mention, because they "are" finishes. Oil is not considered (by the industry) as a finish.
A finish bonds to wood and leaves a hard protective layer that protects the wood from damage due to liquids and dirt ( the better finishes also protect from UV and damage from solvents, acids and have high scratch and abrasion resistance).
Oil simply saturates the wood.
Oils are considered by professionals as an artisan, or hobbyist finish (sic).
Cheers
tt398 said:
Quite the inverse...
That is not "why" production shops use lacquers or urethanes. To imply that it is simply to expediate a product is false. A high quality lacquer or urethane finish is very laborious and time consuming.
How much time do you think it takes to do a true piano finish?
Production shops use the finishes you mention, because they "are" finishes. Oil is not considered (by the industry) as a finish.
A finish bonds to wood and leaves a hard protective layer that protects the wood from damage due to liquids and dirt ( the better finishes also protect from UV and damage from solvents, acids and have high scratch and abrasion resistance).
Oil simply saturates the wood.
Oils are considered by professionals as an artisan, or hobbyist finish (sic).
Cheers
Re: Re: Oil is for Hobbyists
I tend to agree. I use both oils and precat lacquer. Oils are good for bringing out the grain, but they are anything but durable. Lacquer on the other hand does a fantastic job at being a hard durable finish while still yielding beautiful results. I much prefer lacquer, but can't always spray it.
Lacquer is quick drying, but in my opinion is also a superior finish.
Daygloworange said:
I tend to agree. I use both oils and precat lacquer. Oils are good for bringing out the grain, but they are anything but durable. Lacquer on the other hand does a fantastic job at being a hard durable finish while still yielding beautiful results. I much prefer lacquer, but can't always spray it.
Lacquer is quick drying, but in my opinion is also a superior finish.
I use Nitrocellulose Lacquer and post-catalyzed polyurethane from Ilva Polimery T000 series.
I have to say that while oil finish doesn’t provide any scratch resistance, it has a degree of chemical resistance. It has a very specific look that some people prefer. If I had a table made out of solid slab of Walnut, something similar to Nakashima designs, I would probably oil it.
Good lacquer finish does take a lot of time as well as polyurethane. Best 1930th French Art Deco pieces were finished in lacquer. Alas, like anything else it could be a cheap and quick way out for a production shop. Most people associate word polyurethane with Home Depot style poly, brash lines and badly finished floors. There are different types of poly for different purposes.
To make a long story short, lacquer, polyurethane and oil finishes have their own appearance, advantages and disadvantages. As a small woodworking shop I would only use oil if so required by the customer.
Grand pianos now days are done either by hand with shellac (French polishing, very $$$) or they are finished in Polyester.
I have to say that while oil finish doesn’t provide any scratch resistance, it has a degree of chemical resistance. It has a very specific look that some people prefer. If I had a table made out of solid slab of Walnut, something similar to Nakashima designs, I would probably oil it.
Good lacquer finish does take a lot of time as well as polyurethane. Best 1930th French Art Deco pieces were finished in lacquer. Alas, like anything else it could be a cheap and quick way out for a production shop. Most people associate word polyurethane with Home Depot style poly, brash lines and badly finished floors. There are different types of poly for different purposes.
To make a long story short, lacquer, polyurethane and oil finishes have their own appearance, advantages and disadvantages. As a small woodworking shop I would only use oil if so required by the customer.
Grand pianos now days are done either by hand with shellac (French polishing, very $$$) or they are finished in Polyester.
Paper backed or wood backed is a great way to go as it simplifies the installation process substantially. I like using raw veneer because I like the challenge and because I can buy really heavily figured veneers in the raw form for much, much cheaper than I can buy backed.
With backed veneer, pva glue, and an iron, veneering can be a really quick process, and yield great results at the same time.
With backed veneer, pva glue, and an iron, veneering can be a really quick process, and yield great results at the same time.
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