Can hobbist buy and spray pre-catalyzed lacquer on site?

[tjbnwi]

Bull, properly set the overspray is darn near nonexistent on an HVLP. If you're getting overspray that is uncontrollable something is set incorrectly for the product.

Airless due to rebound will disperses the overspray over larger areas. Sherwin Williams makes a dry fall paint to add in cleaning up the mess an airless will make.

This is a Fuji Q4, with pressure pot set at 18 psi, KA+ through a T-70 gun with an 0.8 nozzle/needle set-1.0 air cap. No "mist" in the air, there is no direct ventilation draw at the spray point.

Tom

This is an SW additive, does it have a name?

You are mismatching aircaps with nozzle/needle set?  What are you gaining with this?

I don't understand your question Bill. What additive, I did not mention one in my post.

Wider fan.

Tom

Ah!  That must be a typo, as you meant "aid" instead of "add" and I misunderstood.  I found the SW dry fall paint now.

The Fuji T-70 has a 1"-15" pattern adjustment knob, pattern changes with air caps?  Sorry, I'm not following that.

Yes, my typo.

Spray a product with the matched cap, then spray with a larger and smaller cap. You'll find the product breaks up differently and the pattern will change without changing the setting.

Tom

 

[junk731]

I have to agree with Rick the fog is pretty evident from about 1:20 minutes on and gets heavier with more spraying. I wouldn't have expected anything less in the situation your spraying especially from HVLP turbine which has a transfer efficiency of about 75% on a good day. Nice system for spraying the doors, makes it fast and efficient.

John

 

[wptski]

Yes, my typo.

Spray a product with the matched cap, then spray with a larger and smaller cap. You'll find the product breaks up differently and the pattern will change without changing the setting.

Tom

I can see atomization changing as the air cap holes get smaller as nozzle/needle size drops and I think the Gxpc adds two more holes at 1.0mm.  I do remember watching a video on a HVLP system where the included spray gun had switchable air caps for different materials.

It does sound like an interesting thing to try though.

 

[wptski]

I have to agree with Rick the fog is pretty evident from about 1:20 minutes on and gets heavier with more spraying. I wouldn't have expected anything less in the situation your spraying especially from HVLP turbine which has a transfer efficiency of about 75% on a good day. Nice system for spraying the doors, makes it fast and efficient.

John

I think what you are seeing is because the lighting is directly above a one door but farther behind on others and the camera angle is different.  Video quality has lots to do this too.

 

[JCLP]

Just ordered a gallon of BM Dura-Laq Waterborne acrylic to try out. Should get it late today or Monday. Can't wait to try it.

JC

 

[tiralie]

Even the guy from SW told me that he wouldn't sell the kem aqua to me.

Just go to a different SW dealer and ask for it. Some guys are more conservative than others.

I am pretty confused that I saw many videos on youtube as ppl spray lacquer in the kitchen and bathroom.  They don't seem to have that kind of problems.

Just because someone has a video on You Tube spraying lacquer in the kitchen and bathroom without ventilation doesn't make it correct.

Can you please shed the lights for me what I need to do to get the product and spray safely? Is my only option to spray BM advance at this point?

You need to have ventilation for optimum results when spraying KemAqua. You can spray it without for a small door or two but in a confined space a fine powder will settle on everything. Because these paints dry quickly, and the air from the turbine is warmer, the paint flashes off very quickly. I have sprayed without adequet ventilation and it makes a huge mess.
Tim

 

[tiralie]

HVLP generates huge amounts of very fine overspray by its very nature. You are propelling the product toward the workpiece with large volumes of air, that must bounce off the surface, and with it carries a lot of the finer product with it.

I agree that an HVLP system generates a lot of very fine airborne particles of paint and it gets everywhere unless the room is sealed and properly ventilated.
The nanny in the most recent home I sprayed KemAqua in will spit many colorful obscenities in English and Italian as testament to the mess I made.

I am not sure that in most cases (unless it is coming out of a pressure pot etc.) the air is bouncing off the surface so much as it is particles that never make it to the surface because they become air borne as a result of being dry shortly after it leaves the gun.
Tim

 

[Michael Kellough]

HVLP overspray?

"is particles that never make it to the surface because they become air borne as a result of being dry shortly after it leaves the gun."

That's what seems to be going on to me. Dry particles are manged pretty well by a good exhaust system but that's hard to arrange in someones kitchen. If you have the skill, and equipment airless might be better.

 

[junk731]

Even airless produces overspray and very fine particles just because air isn't used does mean there is no overspray or mist in the air,  that why they call atomization. The only way to get better than about 85% transfer is with a brush.

John

 

[Rick Christopherson]

HVLP generates huge amounts of very fine overspray by its very nature. You are propelling the product toward the workpiece with large volumes of air, that must bounce off the surface, and with it carries a lot of the finer product with it.

I agree that an HVLP system generates a lot of very fine airborne particles of paint and it gets everywhere unless the room is sealed and properly ventilated.
The nanny in the most recent home I sprayed KemAqua in will spit many colorful obscenities in English and Italian as testament to the mess I made.

I am not sure that in most cases (unless it is coming out of a pressure pot etc.) the air is bouncing off the surface so much as it is particles that never make it to the surface because they become air borne as a result of being dry shortly after it leaves the gun.
Tim

Yeah, you're correct. It's just a matter of semantics. The particles themselves aren't bouncing off the surface, because if they had reached the surface, they would have adhered. It is the carrier (air) that is bouncing off the surface, which then carries the product with it.

It doesn't matter how much or how little carrier air you are sending out with the product, because none of the carrier applies to the surface. All of the carrier must reflect off the surface, and with it, so does the product.

I'm surprised by the backlash. This really isn't a controversial topic. It is well understood in the finishing industry. It's a myth that clings on mainly in the hobbyist market.

 

[jimbo51]

http://www.spraygunworld.com/Information2/Overspray/OversprayStart.html

I do not know how old this reference is, but it has a chart showing much better performance with HVLP than airless if I am reading the chart properly.

Even small paint droplets are much denser than air so that a portion of them can pass through the bounce back air and still hit the surface where they will usually stick.

 

[Rick Christopherson]

Jimbo, your link is for a website that sells HVLP equipment. Read the rest of the site, and you'll see that they have an extreme bias against airless.

But if you really want to find out how bad the overspray is, simply spray something with pigment. I did that once, with a very expensive turbine system. The whole room turned brown with a nice even coating, not just where I was working.

 

[usatu]

For professional guys, is the best practice to take the cabinet cases to the spray booth in shop and spray? It sounds like a lot of work like taking the counter top off for repainting the cabinets. Any suggestions for me to paint the cabinet case, brush or HVLP spray? I have many windows in the sun room next to kitchen. Don't know whether that helps or not.

Thanks !

 

[tiralie]

For professional guys, is the best practice to take the cabinet cases to the spray booth in shop and spray?

Yes. I prefer to spray parts and then assemble. It's easier and less moving of bulky pieces. Sometimes it's not possible because of the design and construction but in most cases the more troublesome areas like spraying inside a box etc. are taken care of.

It sounds like a lot of work like taking the counter top off for repainting the cabinets. Any suggestions for me to paint the cabinet case, brush or HVLP spray?

Hmmm, since it sounds like you have not done this before you should brush it. Use a good quality paint like BM Advance or similar and buy a good brush/roller and do some practicing to see what works best. Some people like to use a stiffer brush with Advance and some like a medium etc.

Based on your questions, I suspect you will be very frustrated trying to spray your kitchen. Everything that is not going to be painted needs to be masked. All windows and trim needs to be covered etc. etc. Paint and dust gets everywhere otherwise.
Tim

 

[tiralie]

It could be OTC regulations.  KA contains VOCs even thought it is water-reducible.

What is the OTC?
Most waterborne products contain small amounts (1% give or take) of VOC's. All the documentation I have read on the industrial waterbourne products I use have small amounts of VOCs but pass government regulations for use as long as you are not ingesting it or inhaling the particles.
Tim

 

[tjbnwi]

For professional guys, is the best practice to take the cabinet cases to the spray booth in shop and spray? It sounds like a lot of work like taking the counter top off for repainting the cabinets. Any suggestions for me to paint the cabinet case, brush or HVLP spray? I have many windows in the sun room next to kitchen. Don't know whether that helps or not.

Thanks !

Judge for yourself, look at protected areas. How much overspray has fallen on it?

A kitchen sprayed in place the tops were being replaced, so they were removed. The floor was covered minimally, areas that were to be tiled were not covered, interiors were protected, light on dark protection.

View attachment 2View attachment 3View attachment 4View attachment 5

Tops fabricated and installed..

View attachment 10View attachment 11

Window sashes sprayed, again light color, dark protection.

View attachment 6View attachment 7

Casework, medium color, light floor protection.

View attachment 8

Black edge shot.

View attachment 9

All of the above was shot with an HVLP. Again, properly set overspray is minimal and easily contained.

There are system that produce less overspray (powder coating and ESD, robotic sprayers help also). I doubt we'll see them for our applications in our life time.

Tom

(Edit; I mixed up a few pictures, you'll figure it out)

 

[tjbnwi]

I'll mention again, whatever you decided shoot only waterborne products. You're not set up for solvents.

Tom

 

[Cheese]

I'll mention again, whatever you decided shoot only waterborne products. You're not set up for solvents.

I assume you're concerned with the explosion risk?

 

[wptski]

Tom, do you use a Zipwall system for containment?

 

[tjbnwi]

I'll mention again, whatever you decided shoot only waterborne products. You're not set up for solvents.

I assume you're concerned with the explosion risk?

Yes.

Tom