Fisheye from a Spray Can...Why?

[yyz2112]

I am using Deft Semi-Gloss Aerosol Lacquer, and after 4 or 5 coats from the same can, the finish has started bubbling a little and fisheyeing quite a bit. Why would this happen and how can I remedy it?

 

[mayfly]

I'm not a finishing expert, but I do know this - you've got some impurities (silicon or some other crap) on the guitar that the finish is not adhering to.

You have two options:

1 - sand back to bare wood and try it again
2 - use some kind of 'fisheye flowout', but I don't think you can used it with a rattle can.

 

[yyz2112]

I'm not a finishing expert, but I do know this - you've got some impurities (silicon or some other crap) on the guitar that the finish is not adhering to.

You have two options:

1 - sand back to bare wood and try it again
2 - use some kind of 'fisheye flowout', but I don't think you can used it with a rattle can.

I'm really wondering why it didn't develop until I had a number of coats applied. I would think that it would start earlier.
The fisheye flowout material is an additive afaik, so it wouldn't work with a spray can.

 

[Patrick from Davis]

You probably got hand oil or other oils on one of the layers.  In my experience, this will cause trouble.  I had used mineral oil to level/wet sand the layers on my tele, and I didn't get it all off.  I wiped it down with naphtha and follow the general guidelines, but when I started to polish it, it kinda peeled off.  It was a very thin layer of lacquer, so it didn't come off in a sheet or anything, but when looking at it carefully under light you could definitely see it.  Just a problem with not getting all of the oil off.
Patrick

 

[Keyser Soze]

Fish eyes and cratering are typically caused by surface contaminants.  Silicone being one of the worst offenders primarily because almost nothing can remove the stuff once it is present.  Detergents and degreasers are more effective than simple solvents - which really just dilute the offending agent(s) and spread it around.

Shellac is reasonably effective at sealing off silicone contaminated wood (but not foolproof.) 

I'm not sure what you mean by bubbling, are there actual air bubbles present in the wet film?  If so I'd suggest that your cans are too cold when applying finish.  Try warming them in a bucket of warm water prior to spraying - this reduces viscosity and allows bubbles to more freely escape.  Bubbles may form when the finish is sprayed over small physical defects.  Sometimes the best approach to those is to prick them with a very fine needle (insulin syringes work well for this) while the surface film is still wet (usually on possible with spray gear when the mix is thin and/or you've added retarder - rattle can layers usually skin over way too fast)

 

[Watershed]

I have gotten bubbles from too many coats, too fast, too thick.
I was just being impatient and paid for it.

James

 

[yyz2112]

Thanks for the replies, good info.
The bubbles have given way to craters as I sand between coats.
Now that my finish is pockmarked in this way, what can I do to alleviate this? Will I need to sand back down to bare wood?

 

[dmraco]

are you talking a fisheye or orange peel...there is a difference.  As stated...fisheye is due to impurities.  Orange peel is too much....to fast.

Fish eye must be completely sanded and cleaned...naptha.  then re-shot.

Orange peel can be sanded and smoothed...polished.

 

[Tonar8352]

Now that my finish is pockmarked in this way, what can I do to alleviate this? Will I need to sand back down to bare wood?

Unfortunately the best way to deal with is to sand it back to the wood.  Seal it with Zinsser Seal Coat and then start applying finish in real light coats.  Wait for the coats to get real dry before you add additional finish.  It sounds to me like you got too much on to fast and the earlier coats started gassing out.  

 

[SkuttleFunk]

it's a good rule of thumb not to be eating potato chips while spraying a finish on your instrument

might want to stick this away so you don't repeat this again on your next body

:toothy12:

all the best,

R

 

[uOpt]

I'm really wondering why it didn't develop until I had a number of coats applied. I would think that it would start earlier.
The fisheye flowout material is an additive afaik, so it wouldn't work with a spray can.

Do you do any kind of polishing on the previous coats?