I want to test paint viscosity and want to know more about a viscosity stick and how to use it.

The very best information you can begin with is the information provided by the manufacturer of the paint you wish to spray. When you buy paint be certain to ask for a data sheet.

Nearly all paint apart from some high build primers or spray putty require thinning before spraying. The amount of thinning and the type of thinner will be found on the paint data sheet. Accurate thinning is important and it will be stated as the time the paint takes to run through a viscosity cup so you will need a clean jug in order to thin the paint, a viscosity cup and a clock with a second hand.

There is a lot of information online telling the novice about the core skills a painter needs. You need to observe these basics and then practice, practice, practice. There isn't room here to describe all you need to know but if there is something specific that is bothering you; please come back...

Using a Viscosity Cup

1. Completely submerge the cup in the coating to be sprayed.
2. Lift the cup out of the coating and begin timing until the first break in the stream of material coming out of the bottom of the cup. Measure in seconds, a stopwatch will be helpful.
3. Consult the manual supplied by the manufacture for viscosity recommendations

Refer to the paint manufacturer's data sheet to ensure the new gun has the right setup for clearcoat.

Could be the new gun was supplied setup for spraying a high solids primer or something that needs something like a 0.7 mm fluid tip. Clearcoat would need a 0.4 mm tip, an appropriate needle and a different air cap.

Data sheets are very valuable things. Don't forget to pick one up when you buy spray paint. A viscosity cup is another useful addition to the tool kit along with a graduated paint stirring stick.

add drop of blue and this should solve the problem,

for future reference - what paint? aquarel? pastel? oil? acrylic? tempera?

solvent sometime can be a problem, if you use varnish - varnish naturally turns bit of yellow, sometime pinkish tint, but you need to check if solvents are compatible.

there is heaps of variables in paint mixes, you need to check purity of the pigment (rutile ore contamination's will tend to discolour pigment anything between brown and pink for example with the age), you need to check opacity of the paint (how transparent it is - background may cut through it and sublight it red), you need to check viscosity (light viscosity and dry pigment in wet on wet will "suck" paint from the background), all of these need to be check.

if you have more questions on the subject - you need to provide what medium you use and what is exactly effect.

hope this will help you - do not forget to vote...

I had an airless sprayer years ago. I couldn't work out how to thin the paint either. The end result was if its too thick and wouldn't spray, I added more thinners. If it sprayed blobs and ran everywhere, I added a bit more paint. Not very professional but I got it down pat after a few errors. I wrote on the paint can I was using, the mix that worked the best.

Paint sticks offer a different way to work with oil paint. Rather than using a brush, you hold the paint stick in your hand to create different lines or textures than you could with a brush.

Assuming that you are using the standard 2.0mm tip - MAXIMUM 60 seconds.
The paint manufacturer publishes a data sheet with recommended viscosity for spraying and you should try that first. The data sheet will probably suggest a maximum percentage of thinning as well.
You will find that in order to obtain a nice fine spray 45 seconds through the viscosity cup is about right for most oil paints.

there are several issues that can cause this problem.
I will assume you have used the sprayer before so that will eliminate an incorrect air cap. The only other issues are paint viscosity, worn parts and the number one cause improper cleaning.
Be prepared for a complete disassemble of your gun. Depending on what you spray any residue can become hard as cement and it only takes a small amount to cause problems.
Below is a link to the manual that gives an exploded view of your gun.
Hope this helps but if not please let me know and I will trouble shoot further.

http://www.cpocampbellhausfeld.com/static/manual/www.cpocampbellhausfeld.com-dh5300.pdf

Have a look at the instruction manual. It should state the viscosity that the paint should have. Use a viscosity cup to measure the time the paint takes to drain from the viscosity cup. Dilute the paint if it takes too long.

There are a number of possible causes.
These are compounded by the different types of guns like HVLP and what would an older style. Also are you using a pressurized, gravity feed or siphon gun.
However, the reason for spatter is improper atomization of the air and paint. The most common causes are incorrect air flow or incorrect paint viscosity. If you don't have a way to check the viscosity get one. I painted in factory repair area that used a pressurized system. On any given day there might be 9 to 12 colors we used. Each one would have a different vis. Air adjustments could range from 50 psi. to 95 psi. This will hold true for almost any type of paint.