Need Lacquer HELP

[Oldwildcat]

I am trying Lacquer for the first time and it just turned into a disaster, after the second coat with Deft Clear Wood Lacquer ( it said no sanding brtween coats??) it bubbled on me. My queastion is can I sand of the bubbles and also not crazy about the finisn could I Poly over the Lacquer after sanding. I have 40 hours on these Dolphin Sculpture and needless to say I'm sick.

[JohnB]

G'day OWC,
Putting cold finishes over hot is a tricky business.
I don't know what would have made the lacquer bubble??
You can Poly over it, but you have to give the item tooth so the poly will stick.
You can do this by sanding back with no finer than 240g paper and apply thin coats.

My only thoughts re the bubbling, is if you used a pressure pac, perhaps you held the can to close to the project and put the lacquer on to thick, thus introducing air to the finish. Unlike Poly, Lacquer is designed to be applied in a number of thin coats, cutting back between each. I have seen a number of products that claim no sanding between coats is necessary, but have yet to find this is true to obtain a nice finish.
Good luck and you items are not beyond redemption.

[Forester21]

John, I can usually figure out what you are saying (pressure pac = aerosol can) but can you explain what you mean by cold finishes vs hot? Thanks
T

[Wood Dog]

I remember I had bubbles with spraying on Deft once,because it was too cold in my attic at the time, it was raining outside and I don't like to spray in the house or shop, so I use the attic, but on this particular day it may have been too cold up there.
I just sanded everything down, and resprayed when it was warmer.

[handibunny]

When I've had a lacquer disaster, I used acetone to remove the whole mess and started from scratch. I use Minwax spray lacquer, and find that it is almost, but not quite, idiot-proof.

I usually have to do some rubbing down (using 0000 steel wool) between coats unless I'm really lucky. And thin coats are the only way to stay out of trouble.

[Bill Wilson]

OWC,

Could you give us a few more details about the way you applied the lacquer, what the conditions were when you applied it and as it was drying? I don't have a lot of experience with lacquer, but I would hope that you could salvage the existing finish, before doing anything drastic.

Did the finish dry completely? If so, then it's probably not a problem with the product itself, such as it being old. You can probably safely sand it down smooth and either try another coat, or top with something else, but I would like to know more about your application technique and the temperature/humidity at the time you applied it before making a further suggestion.

I know it's too late now, but the best advice I've ever gotten or read when it comes to trying new finishes, is to always test it first on a piece of scrap of the same wood and prepared in the same way as the end item. That way you can avoid unpleasant surprises on a project in which you've already invested significant time & effort.

Good luck, hope this helps.

[Jim Finn]

I learned long ago that heating a spray can of any finish in hot tap water helps the spray work well.

[Ron Standley]

I have had bad luck with lacquer. Read somewhere (here?) that there should be at least 20 degrees difference between the temperature and dew point. I live close to Seattle so we get that condition about once a year. I don't even try anymore.

[JohnB]

G'day Theresa,
Here goes, it not hard and fast but generally this is the meaning.

A hot finish is a coating that has a chemical reaction to set it of. eg Lacquer will only set if mixed with thinners.
Hot finishes also adhere to the previous coat by softening it, thus making the multiple coats one solid coat.

A cold finish would be Poly, Varnish etc. These rely on the air and evaporation of the carrier to set up.
Once a coat is dry, the second coat requires some method of bonding to the previous one. This is normally done by cutting back each successive coat with a fine (not to fine) paper about 240/220g.
If this "Tooth" isn't provided you effectively get multiple layers of very thin plastic. This may last for years, or if exposed to sunlight or knocked and chipped the layers may start to separate.
Hope this is as clear as mud.

The problem with placing cold over top is

John, I can usually figure out what you are saying (pressure pac = aerosol can) but can you explain what you mean by cold finishes vs hot? Thanks
T

[Forester21]

Thanks John!
You explained the difference great -but the message stopped when you got to the problem of using both....

T