Does anyone use “Smoothie” (silicone) in their lacquer

[Quickstep192]

There’s a very interesting thread on one of woodworking forums I frequent about the practice of adding silicone (Brand name Smoothie) to lacquer to prevent fisheyes caused by silicone.

A guy did an experiment on a piece of furniture that had silicone contamination.
He got lots of fisheyes because the prior finish had been contaminated. When he added silicone to his lacquer, it flowed out beautifully.

I don’t have fisheye problems per-se, but I almost always get craters in my finish as it’s drying. This is on bare wood with no silicone in the area.

So, I’m considering trying Smoothie, but I’ve read that once you use it, your gun is contaminated forever and you must then use smoothie for eternity afterward.

Since I know there are people here who shoot a lot of lacquer, I’m wondering what others are doing.

[mirwa]

If you are getting craters in your finish and its clean wood, then yes it is likely you have a silicon issue in either your compressor, your air lines, your spray guns or your enviroment.

Whilst yes you can use an additive and yes it does make it difficult to spray paints again without it, I personally would try to identify the cause.

Do you buff near your paint area, do you have machines near your paint area, are you cleaning the wax and grease remover off after using it, lots of causes, just got to try and find it

Steve

[Quickstep192]

Originally Posted by mirwa

If you are getting craters in your finish and its clean wood, then yes it is likely you have a silicon issue in either your compressor, your air lines, your spray guns or your enviroment.

Whilst yes you can use an additive and yes it does make it difficult to spray paints again without it, I personally would try to identify the cause.

Do you buff near your paint area, do you have machines near your paint area, are you cleaning the wax and grease remover off after using it, lots of causes, just got to try and find it

Steve

I've been trying to identify the cause for quite a while now. I've replaced the compressor and the hoses, but I still get craters. I'm practicing on 2' x 2' pieces of maple plywood. On any given coat, there might be 5-6 craters in the 4 sq ft area. It happens with nitro and waterborne, but not with shellac.

Anyway, after seeing the results the guy on the other forum got, I'm thinking about crying uncle on the cause and commencing the addiction to silicone.

[Howard Klepper]

Don't weaken.

Are there any spots of CA glue where you got craters?

[Edgar Poe]

I would not allow any product with silicone within eye sight of where I spray on my finish.
It may work, I have no idea, HOWEVER, you have then introduced silicone to your entire spraying environment, and equipment. If you pick something up and the touch a project, you may have issues. I DON'T KNOW. In my mind not worth the chance. Just the word Silicone scares me around finishing.

Ed

UPDATE; I CHECKED THE MSDS OF SMOOTHIE II, IT DOES NOT CONTAIN SILICONE.

I based my original post on this line of the OP thread. My apologies.
Quote:"There’s a very interesting thread on one of woodworking forums I frequent about the practice of adding silicone (Brand name Smoothie) to lacquer to prevent fish eyes caused by silicone."

Here is the link to MSDS:

http://images.myautoproducts.com/ima...20242_MSDS.pdf

[djb33]

Originally Posted by Edgar Poe

UPDATE; I CHECKED THE MSDS OF SMOOTHIE II, IT DOES NOT CONTAIN SILICONE.

I based my original post on this line of the OP thread. My apologies.
Quote:"There’s a very interesting thread on one of woodworking forums I frequent about the practice of adding silicone (Brand name Smoothie) to lacquer to prevent fish eyes caused by silicone."

Here is the link to MSDS:

http://images.myautoproducts.com/ima...20242_MSDS.pdf

Edgar, the MSDS that you linked actually does show a silicone among the ingredients. This one:
GLYCOLS, POLYETHYLENE, METHYL 3-[1,3,3,3-TETRAMETHYL-1-(TRIMETHYLSILOXY)DISILOXANYL]PROPYL ETHER

The terms "trimethylsiloxy" and "disiloxanyl" in the name indicate a that it belongs to the family of materials that are commonly called silicones.

However, the structure of the "Smoothie" silicone is much different than the structure of the silicones that are typically used as ingredients in polishes, which are the ones that cause fish eyes when they contaminate coatings.

To, the OP, I'm surprised to hear that "Smoothie" requires a lifelong commitment...once you put it in your gun, you have to use it forever. I guess if you stopped using it and saw problems, it would be hard to know if they were caused by the smoothie or by whatever other problem you had that made you start using smoothie in the first place.

3M has a good techincal service organization. Suggest you contact them to hear what they say about your concern of having to use it forever.

Dave

[Quickstep192]

Originally Posted by Howard Klepper

Don't weaken.

Are there any spots of CA glue where you got craters?

Great question, but no, there's no CA where the craters are occurring. In fact, the craters appear in different locations in each coat. They also vary in quantity - sometimes just a few other times 6 or more, but it's never dozens and unfortunately, never zero either. For what it's worth, the finish goes on perfectly at first; the craters appear later in the drying process. I'd love to blame contaminated air, but I recently switched to an oil-less compressor and got all new hose. There's an oil/water separator at the compressor, a 25' hose, then a desiccant filter, 6 feet of hose to the gun and the gun has a filter, so it's a little hard to believe that my air isn't clean.

Oh by the way, the spraying conditions were ideal. 70° & 50%RH.

As I mentioned, the craters are relatively few and the sand out, but they do require a fair amount of sanding, so I sanding away good finish to do that and wouldn't it be nice to get an "off the gun" coat just one time?

[Howard Klepper]

Originally Posted by Quickstep192

Great question, but no, there's no CA where the craters are occurring. In fact, the craters appear in different locations in each coat. They also vary in quantity - sometimes just a few other times 6 or more, but it's never dozens and unfortunately, never zero either. For what it's worth, the finish goes on perfectly at first; the craters appear later in the drying process. I'd love to blame contaminated air, but I recently switched to an oil-less compressor and got all new hose. There's an oil/water separator at the compressor, a 25' hose, then a desiccant filter, 6 feet of hose to the gun and the gun has a filter, so it's a little hard to believe that my air isn't clean.

Oh by the way, the spraying conditions were ideal. 70° & 50%RH.

As I mentioned, the craters are relatively few and the sand out, but they do require a fair amount of sanding, so I sanding away good finish to do that and wouldn't it be nice to get an "off the gun" coat just one time?

Sure it would be. But unless you are Steve (Mirwa), sanding and rubbing out is to be expected.

Silicone is very hard to get rid of of once a small amount is in the environment. You may have played someone's guitar that was polished with it months ago and then gone into your shop and worked on something without having first scrubbed your hands. But you don't want the guitars you send out from your shop to be carriers of a disease that could infect others.

Try this: spray a thin, light coat of shellac over the raw wood as a sealer. Zinnser seal coat, which is a 2lb cut shellac, works well if you don't want to bother mixing. Just mist it on--it's okay if it dries without flowing out. Then spray lacquer after the shellac is well dried and see if the shellac has sealed in whatever was the contaminant.

[runamuck]

Aerosols that contain silicone can travel quite a ways. I once worked in a large shop where the finishing room was upstairs, 150 feet or so from where someone sprayed silicone for about 3 seconds. Everything that was in the process of being lacquered had to be stripped.

[mirwa]

How about a different bit of troubleshooting then

Have a paint shop mix you paint in spray cans or buy it in spray cans, do your prep work as per normal and lets see if you have contaminants in your finish

This will at least identify the system you are getti g the fish eyes from, the prep stage or the finish stage or the enviroment

Steve

[Quickstep192]

Originally Posted by Howard Klepper

Try this: spray a thin, light coat of shellac over the raw wood as a sealer. Zinnser seal coat, which is a 2lb cut shellac, works well if you don't want to bother mixing. Just mist it on--it's okay if it dries without flowing out. Then spray lacquer after the shellac is well dried and see if the shellac has sealed in whatever was the contaminant.

I always use shellac as a seal coat. The craters come in the subsequent coats of lacquer. It doesn’t occur when I spray nitro from a rattle can (the waterborne isn’t available in a rattle can). This would seem to point to the equipment, but after having changed the compressor and the hose and having cleaned the living snot out if the gun, even though I know I’ve never had anything in the gun but finish, it’s hard to imagine where it’s coming from.

By the way, the shellac sprays beautifully; no craters at all on the first or any subsequent coats.

That’s kind of why my original post was about the use of Smoothie. I think I’m at the point where I just give in and go down the slippery slope with Smoothie, or get a Turbine HVLP System where I know the air is clean, warm and dry.

[mirwa]

So spraying nitro from a rattle gun does not cause the suspected fisheyes, but nitro from your spray system does?, i ask specifically as you do not mention nitro out of your spray gun but water borne lacquers.

If this is so it rules out the enviroment and climate and prep process.

The other question i have is are you using the same spray gun for spraying the shellac as the nitro coats?

Warm air is not the best for painting, the cooler you can keep the air the better.

Steve

[Quickstep192]

Originally Posted by mirwa

So spraying nitro from a rattle gun does not cause the suspected fisheyes, but nitro from your spray system does?, i ask specifically as you do not mention nitro out of your spray gun but water borne lacquers.

The other question i have is are you using the same spray gun for spraying the shellac as the nitro coats?

Steve

Yes, same gun for shellac as for other coats. As I mentioned, I don’t get craters in shellac, just in nitro and waterborne. I’ve mostly been spraying waterborne lately in an effort to move away from nitro.

[mirwa]

After spraying the shellac (what brand if we could), how are you cleaning the gun in prep for the nitro coats.

Its evident you are picking up a contaminant in your spray system, be that the compressor, air traps, hoses, pressure regulators or spray guns or cleaning of guns

You wont get craters in shellac when spraying with say a contaminated system, as the shellac seals the contaminants in

Steve

[Quickstep192]

After spraying shellac, I clean the gun with DNA. I usually mix my own shellac, or use Zinsser seal coat thinned to a 1.5# cut.