# Over spray?



## hawkeye10 (Jul 28, 2015)

I have been using rattle cans to spray my projects but they seem to have a lot of over spray. I have been trying to suck it into a box fan with a pleated house filter and that helps but not good enough. I have been thinking about getting one of the HVLP sprayers. To what degree will this cut down on over spray?


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## schnewj (Nov 18, 2013)

Don, 

A little more context would help. What types of things are you spraying? Flat surfaces, inside corners, large/small projects, etc.

HVLP (High Volume Low Pressure) will certainly cut down on some of the overspray, but will not totally eliminate it. If you are spraying small items then rattle cans can be a blessing if used correctly. Most folks spay on too heavy instead of backing off and doing several light coats. It takes practice to get *good* results. 

HVLP are great for larger surface area projects, but require more effort. The downside to HVLP is the cost of the equipment if you don't already have it availiable; set-up and adjustment time, and certainly clean-up have to be taken into account. 

I have expanded my HVLP gun collection over the past couple of years. It is easier and sometimes cheaper to buy a whole gun then to buy a different size tip. But, I spray everything from waterborne stains to enamel and acrylic paints.

You might be better served to construct a portable spray booth and continue with the spray cans depending on the scope of your projects. Another alternative is something like an Earlex HVLP spray system that typically runs around $300. In any event, you won't eliminate overspray entirely. You will have to control it.


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## Mike (Nov 22, 2004)

Don, it sounds like your problem may be in how you are using the rattle can; I know I had problems with this for a long time. Give this method a try and see if it helps:

Turn your box fan on it's lowest speed and have it about 3' behind your project. Hold your can parallel to the surface and begin spraying to the side of the project and sweep across with a slow steady speed holding the can about 16" away. Do not stop spraying until you are past the edge. Don't make the mistake I did and hold the trigger down sweeping back and forth. Work from the edge closest to you towards the fan with about 1/3 overlap in each pass. This is how I get the best results.

It is likely you would get the same results with an HVLP sprayer you are getting with the can. An HVLP sprayer will provide you with a regulated spray that won't vary the way a can does as it empties. The cost of your chosen finish is much lower in larger quantities.


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## schnewj (Nov 18, 2013)

Mike said:


> Don, it sounds like your problem may be in how you are using the rattle can; I know I had problems with this for a long time. Give this method a try and see if it helps:
> 
> Turn your box fan on it's lowest speed and have it about 3' behind your project. Hold your can parallel to the surface and begin spraying to the side of the project and sweep across with a slow steady speed holding the can about 16" away. Do not stop spraying until you are past the edge. Don't make the mistake I did and hold the trigger down sweeping back and forth. Work from the edge closest to you towards the fan with about 1/3 overlap in each pass. This is how I get the best results.
> 
> It is likely you would get the same results with an HVLP sprayer you are getting with the can. An HVLP sprayer will provide you with a regulated spray that won't vary the way a can does as it empties. The cost of your chosen finish is much lower in larger quantities.


Certainly good points. The technique applies to ALL types of spray systems. Most people spray with the cans too close and try to cover completely in one or two passes. Instead, as Mike says, back off, mist on a layer in an even coat, and do several passes until it is covered.

With an HVLP you would typically move closer, depending on the tip size, pressure, and the material being sprayed.

No matter what system(s) you use, you will have to deal with overspray.


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## Cherryville Chuck (Sep 28, 2010)

You might want to consider getting an airbrush for small projects. I use mine for items up to the size of burl clocks. Very little overspray and excellent control. They also use very little air so you don't need a big compressor. Even good ones like a Binks aren't all that expensive.


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## schnewj (Nov 18, 2013)

Cherryville Chuck said:


> You might want to consider getting an airbrush for small projects. I use mine for items up to the size of burl clocks. Very little overspray and excellent control. They also use very little air so you don't need a big compressor. Even good ones like a Binks aren't all that expensive.


Another good suggestion on how to control the overspray, Chuck. 

Without knowing the scope of the projects it is hard to pinpoint the control advice.


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## hawkeye10 (Jul 28, 2015)

I mostly spray small projects like the clock in my avatar. I have been spraying lacquer which dries faster and cuts down on over spray getting all over everything but still I have the problem. I have made a small spray booth out of a card board box about 2 foot square with the box fan behind it and short cardboard sides but no top. I have also been making a few corn hole boards and painting them with laytex house paint. I am using a 4" roller to paint them so the painting goes pretty quick but it's the curing time that is slowing me down. I have been waiting 2 days before using painters tape to make designs.

I have read about the Earlex 5500 and while it's not the best sprayer it does a pretty good job of spraying just about any thing. I think first I will make a better spray booth and see how that works.


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## BernieW (Sep 12, 2006)

Don I use a spray booth I got from Chicago Airbrush and run a dryer ducting to a duct outside run at full speed. I also use a airbrush I got from them that has a nozzle like the HVLP guns. I also use EM6000 waterbased lacquer from Target Coatings which dries fairly quickly and will also burn into the last coat like regular lacquer. I use a smaller compressor and have very little overspray problems or less than a spray can. I also spray lots of small turning projects and antique clocks that I restore. When I used a fan I would have it setting about 12 to 24 inches from the piece I was spraying and running full out. 

One thing I forgot to mention is there are no what I call toxic smell using WB Lacquer over regular lacquer. So I can spray inside all year round. Just some idea's of things that have worked for me for many years.


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## DaninVan (Jan 1, 2012)

Hey, Don; I'm not sure if this applies in the setup you're talking about, but if the spray is confined, like inside a box, the backpressure from the 'booth' will deflect the spray, forcing it off to the side and back at you. Sort of like trying to blow up a partly inflated ballon. To be really effective, the air pressure in the 'booth' would need to be lower than the surrounding environment; basically suction down or out the back.
You really see this effect when using any kind of air type sprayer and trying to paint an inside corner.

I just read Bernie's comment and he's saying the same thing; lots of air moving _away_ from your project.


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## schnewj (Nov 18, 2013)

hawkeye10 said:


> I mostly spray small projects like the clock in my avatar. I have been spraying lacquer which dries faster and cuts down on over spray getting all over everything but still I have the problem. I have made a small spray booth out of a card board box about 2 foot square with the box fan behind it and short cardboard sides but no top. I have also been making a few corn hole boards and painting them with laytex house paint. I am using a 4" roller to paint them so the painting goes pretty quick but it's the curing time that is slowing me down. I have been waiting 2 days before using painters tape to make designs.
> 
> I have read about the Earlex 5500 and while it's not the best sprayer it does a pretty good job of spraying just about any thing. I think first I will make a better spray booth and see how that works.


Don,

Thanks for the context. Now we can address the real issue in a logical manner. 



I can offer a few options and suggestions. However, you are the ultimate determiner of what will work for you.

The first step is, indeed, a better spray booth. If you do a search I'm sure that you will find something that will work and fits your physical space needs. I believe that Woodsmithshop.com did a fold up, wall mounted, spray enclosure in the past year or so. You might start there. There are a lot of other examples out there. I'm sure that there are some of the members here that can offer some help.

Since you are doing small(er) projects. Chuck's suggestion is a valid alternative. An airbrush is great at doing small things, and the overspray can be kept to a very manageable level. However, you might be limited by the volume of the reservoir. Larger containers are available, however.

If you have a compressor handy a small HVLP may be a viable alternative. I'll take heat from certain quarters, but I do have a HF touchup gun with a 0.8mm tip. It is fantastic for spraying waterborne finishes on smaller areas. It is limited by the 4 oz cup but would be perfect with an 8 oz replacement. It was cheap and at the price no loss if I eventually have to replace it. So far, it has not let me down. However, I am just spraying water and/or alcohol through it and not a heavier material or pigment.

For spraying Lacquer you could probably use a 0.8 - 1.2 mm tip and be OK. Some of the spraying experts may need to weigh in here as I am not the expert here. 

If you continue to use spray cans follow the label directions. Most will call for a 12" *maximum* distance, for lacquer that will probably be a little closer. If you get out too far, the material is dry before it hits the intended target. This is the reason you get things like orange peel, cloudiness, or flaking finish. If it goes on dry it won't stick or provide a finish that has "flowed" and leveled out when it does dry. Just causes more work. 

Hope this helps.

Edited: Sorry, I was a little slow on this post and I see that Bernie and Dan slipped in ahead. Both have offered good advice.


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## schnewj (Nov 18, 2013)

Don, 

Consider something along the lines of these examples. The real trick is as Bernie and Dan stated, that, volumes of air flow and an adequate area to prevent blow back. Both important considerations.

Knock-Down Spray Booth

http://www.finewoodworking.com/how-to/article/make-a-simple-spray-booth.aspx


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## schnewj (Nov 18, 2013)

Don,

Rereading your original post I see that you are having problems with the latex paint on the Cornhole game. Consider getting away from latex and going to a spray enamel. I use Rustoleum in both spray cans and through a gun to get some really nice, smooth, HARD finishes. The drying time is a lot quicker then latex and more durable. You will be able to lay out the graphics much quicker.

People seem to forget that the Rustoleum is not just for rusty metal. I will stick to a properly prepared piece of wood like a bulldog on a bone.


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## DaninVan (Jan 1, 2012)

" * (sic)* will stick to a properly prepared piece of wood like a bulldog on a bone."
Sometimes these typos are keepers!


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## DaninVan (Jan 1, 2012)

Oh crap. Serves me right!
Lets try that again...
" *I* (sic) will stick to a properly prepared piece of wood like a bulldog on a bone. "
Sometimes these typos are keepers!


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## hawkeye10 (Jul 28, 2015)

I am going to come up with a spray booth to fit my needs in the comming days. One thing I do know it will have to be folded or taken apart after I am through. Maybe I can improve some over what I have been doing.


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## schnewj (Nov 18, 2013)

DaninVan said:


> Oh crap. Serves me right!
> Lets try that again...
> " *I* (sic) will stick to a properly prepared piece of wood like a bulldog on a bone. "
> Sometimes these typos are keepers!


Great catch, Dan! :laugh2::laugh2::laugh2::laugh2:


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## DaninVan (Jan 1, 2012)

Don; can you lay your hands on a refrigerator shipping carton? Remove the top and vent the back(?)...
A lazy Susan would make the painting a whole lot easier. The lazy Susan hardware is pretty inexpensive and readily available.
http://www.amazon.com/Susan-Bearings-Thick-200-lb-Capacity/dp/B0006LBVDI


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## Stick486 (Jan 4, 2013)

DaninVan said:


> Oh crap. Serves me right!
> Lets try that again...
> " *I* (sic) will stick to a properly prepared piece of wood like a bulldog on a bone. "
> Sometimes these typos are keepers!


some are but not this time...


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## hawkeye10 (Jul 28, 2015)

DaninVan said:


> Don; can you lay your hands on a refrigerator shipping carton? Remove the top and vent the back(?)...
> A lazy Susan would make the painting a whole lot easier. The lazy Susan hardware is pretty inexpensive and readily available.
> Amazon.com: Lazy Susan Bearings, 3", 5/16" Thick, 200-lb. Capacity: Industrial & Scientific


Dan I don't know about the refrigerator carton but I am already using a lazy susan. The box I am using is the big box that my bandsaw came in. I think I just need to build a better surround. The box is about waist high and 2'X2' square. That is big enough for most things I make. I hope I don't have to make any more cornhole boards. Besides not liking to make them a guy close by is selling them for $100 including bags. They are well built and painted up nice. :frown:


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## Stick486 (Jan 4, 2013)

hawkeye10 said:


> I am going to come up with a spray booth to fit my needs in the comming days. One thing I do know it will have to be folded or taken apart after I am through. Maybe I can improve some over what I have been doing.


here's a start...

Make a Simple Spray Booth - Fine Woodworking Article


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## Stick486 (Jan 4, 2013)

hawkeye10 said:


> think I just need to build a better surround. The box is about waist high and 2'X2' square. That is big enough for most things I make.:


here's another...

Spray Booth Small items - Do It Yourself - SurfTalk


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## BernieW (Sep 12, 2006)

Here are a couple of the spray units I use. One is a Paasche Talon with the hvlp tip. The other is a small Grizzly hvlp. Also the Paasche booth is what I use now. The one stick gave a link to is what I used till it got so gummed up with finish. I built the box to fit a box fan and ran it on high speed when I sprayed. The booth I use now I have a dryer hose connected to a dry vent to the outside. The airbrush and hvlp gun are easy to clean with water since I just use water based lacquer.


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## DesertRatTom (Jul 3, 2012)

I solved the overspray by finding a heavy duty cardboard box the same inside dimension as the box fan. Put a filter on the fan, and then cut the bottom out and taped the box to the fan. The flaps on the box spread out a bit and the fan pulls the airflow into the filter. Simple solution that works well for me. Easy to hang on a rafter, out of the way until I need it. You already use a lazy susan. Consider using those little painting cones, or finish nails driven through scrap so you can elevate the piece a bit. I bought disposable gloves for all painting tasks. Many light coats.


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## Litterbug (Nov 30, 2014)

You're putting too much paint on at a time if it takes more than a few hours for latex paint to dry. It's the same as most coatings in that you're aiming for thin coats that dry completely before you add another. Indoor latex seems to dry faster than outdoor, but when painting houses I've put one coat on mid- morning and another by early afternoon. That was in moderately warm temperatures in the desert, but even in humid conditions, an item painted indoors should dry to the touch within hours.

If brushing, dip just the first 1/2 inch of the brush into the paint, wipe off the excess against the rim of the can (no sopping wet brushes!), paint with light strokes to lightly cover, and don't dip again until the brush runs out. If you need to get the paint into corners and crevices stick the tips of the bristles in there and wiggle them around. Good quality paint with lots of pigment should cover in two thin coats. The paint job will last longer and look better, too.

I'm advising you to use latex paint, because there are a lot better looking finishes for woodworking. I'm just explaining how to use it correctly if you do.


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## hawkeye10 (Jul 28, 2015)

Litterbug said:


> You're putting too much paint on at a time if it takes more than a few hours for latex paint to dry. It's the same as most coatings in that you're aiming for thin coats that dry completely before you add another. Indoor latex seems to dry faster than outdoor, but when painting houses I've put one coat on mid- morning and another by early afternoon. That was in moderately warm temperatures in the desert, but even in humid conditions, an item painted indoors should dry to the touch within hours.
> 
> If brushing, dip just the first 1/2 inch of the brush into the paint, wipe off the excess against the rim of the can (no sopping wet brushes!), paint with light strokes to lightly cover, and don't dip again until the brush runs out. If you need to get the paint into corners and crevices stick the tips of the bristles in there and wiggle them around. Good quality paint with lots of pigment should cover in two thin coats. The paint job will last longer and look better, too.
> 
> I'm advising you to use latex paint, because there are a lot better looking finishes for woodworking. I'm just explaining how to use it correctly if you do.


It dries pretty quick but it takes a while for it to cure. There is a lot of paints water base and oil base that dry fast so you can recoat but it takes longer to cure. I am sure you know this.


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## MAFoElffen (Jun 8, 2012)

I use both HVLP and classic suction guns... depending on what I'm painting. I have small detail guns, through larger guns with half gallon remote tanks. Anything bigger is hard for me to handle... and I can only spray so long before I need a break from it.

I am not a great painter, but from the school of hard knocks (not doing something right the first time)... I hate sanding. So If I have to strip something down and re-sand it...


Just a few additional tips I've learned-- 

Make sure you have dry air. You can coil a hose in a 5 gallon bucket with water and ice... before your water separator to help dry your air out (in high humidity).

Make sure you have consistent pressure. Too high will atomize the paint and get too much overspray. Too low will throw drops (too big) onto your work.

Make sure the area and your work piece is somewhat warm. (i've pre-heated some objects in the winter!!!)

Starting out, check your pattern, and how it sprays.

If your position and technique is good and consistent (the first thing to get right, it was discussed previously in this thread)... and you are getting too much over spray, lower your pressure.

If it doesn't lay down right (sandy, pebbly, grainy), use more reducer. It means your finish is not laying down before it kicks, so needs to be thinned. If a spider web or such kind of pattern, hazy, uneven coverage/surface, it means it's kicking off too fast and is too thin.

If it is going to take more than one cup (gun reservoir) of paint to finish a coat, I have someone mix while I paint. They also keep my hoses from messing up my work, and keep an eye on me. That way, I keep a fresh start, to continue, before where I left off kicks.

Use a good respirator with good filters. A dust mask just isn't good enough for me. Use good eye protection that you will just use for painting. Even with DC type of underpressure, some overspray is inevitable, and will ruin good eyewear! (Once you see how much really builds up over time, it will convince you to use good eye and breathing protection!) Wear nitrile gloves.

Make sure there is good, adequate ventilation to _elsewhere_. I almost lost my little brother, when a ventilator failed in a paint booth at his work...

If while you're painting, you notice your pattern change or the size of your paint particles change, first check your tip to make sure it's clean. Second, make sure the vent hole on your cup is clean and clear.


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## Litterbug (Nov 30, 2014)

hawkeye10 said:


> It dries pretty quick but it takes a while for it to cure. There is a lot of paints water base and oil base that dry fast so you can recoat but it takes longer to cure. I am sure you know this.


Does the can say to let it dry for two days? The only time I've seen latex paint take longer than overnight to fully dry is when I've been sloppy and slapped on a coat that's too thick. 

But hey, it's been a while, and I could be flat out wrong. I've certainly been wrong before... :wink:


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## DesertRatTom (Jul 3, 2012)

For small projects, I use a filter and fan in a cardboard box. But I buy the largest, double wall box I can get from Home Depot. The flaps spread out to the side to catch the sweeping overspray. I was watching a Woodsmith video yesterday and they had a neat folding spray booth. made of 3/4 ply. Had 3 folding doors with each set a little further back in the frame. The first door folded down and had a Lazy susan on it. The second and third doors open to the side and have two triangular pieces attached to their bottom edge that attach to the first fold down door. No filter or fan, but it folded pretty much flat against a wall, perfect for a tight space. I bet you could add a fan, but the wings were quite wide so it might not need one. Could not find a picture of it, however. I'll look for one when I get back home.


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