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Need Tips For orange Peel8/11
Hi Guys I am a little green behind the ears and I am still learning.
I just completed a kitchen reface for my in laws that came out ok, but I am having issues of getting a little orange peel with my spraying.
I want that real smooth Glass like finish and it is bothering me.
I am using a cheap( 45.00) husky siphon feed quart cup gun model h4930ssg.
I am thinning my material about 15 to 20 percent with lacquer thinner. I live in Phoenix Az where it has been really hot right now and a little humid as well (monsoon).
I am putting on 2 coats of sealer (sand after each coat) and 2 coats of Lacquer.
My Husky gun seems to not atomize as well as I would like it to, I dont know know if its because of my gun or maybe not thinning enough, or too many coats.
I have a harbour freight hvlp and I dont use it because it leaves a lot of orange peel as well.
I want to buy a new gun but I am afraid to get an hvlp if it leaves orange peel, I have a small shop and I am eager to learn, any advice I would sure appreciate thanks.
HVLP is not the cause of orange peel.
There is a direct correlation between temperature, gun needle/tip size, and amount of thinner required.
Then there is technique, too much and you get orange peel, too little and you get dry spray.
Then there is gun setup, are you using enough atomizing air?
For your sealer and lacquer, a tip in the area of 1.4 to 1.8mm will work fine, and you probably want somewhere around 20psi at the gun with the trigger pulled. Dont read the pressure gauge at the tank, there are losses in the line. Get a little restrictor with a gauge and put it right at the gun to dial your air pressure in.
Get a wet film thickness gauge. Spray coats in the 3 to 5 mil range.
Hold gun about 6 to 8 inches from the part and make 50% overlap with each pass.
Above information should be enough to get you started.
Since you want to learn that is the first and most important step. The above is very good advice. You learn that and just about any equipment will work. With that said, if your up to investing in a new gun, you might want to consider CA Technologies CPR gun with a 3M PPS cup.
I say this because you said you are spraying ML Campbell. CA Tech's site has all the info you need for using ML Campbell products and their equipment (Tip sizes, Viscosity, etc). Plus the CPR guns come as both compliant and HVLP. The best of two worlds. And they are just a phone call away. Their customer support is great.
When I first started spraying, my supplier was a distributor for both. I trusted them and all went well. I now use the CA Tech AAA pump. I need the volume it provides.
So learn to get the viscosity straight for your conditions and deal with the tip you need for your gun. They seem to go hand and hand.
Once in awhile, adding a bit of Retarder to your mix will help. It slows down the dry time and allows the coating to flow out. Experiment on some sample pieces and see how it works out.
Using more reducer is worth a try. I wouldn't hesitate to go to 40 or 50%. Use the manufacturer's reducer- the slowest one they carry for your geography. I would try to get ML tech support to help you get to what you need. Off the shelf lacquer thinner won't cut it.
Precats are high solids and standard lac thinners are fast and loaded with acetone which the govt loves for low voc. However- acetone is difficult to slow down the flash of your coating. Fine in Minnesota but impossible in Phoenix.. Hence, more reducer will help flow out but I still prefer a reducer without large % of acetone but that is getting very hard to find these days.
I would talk to Campbell support- Reducer is important.
Cheap guns, cheap finish. Go to an automotive paint supplier and get a gun. Stop shopping where they only sell Chinese knock-offs. By the way, a lot better finishes than lacquer for kitchens. It's going to fail around the dishwasher, sink, and stove in just a couple of years.
What kind of compressor are you using?
Hey thanks a lot for all the help I have received from everyone.
I did some of the suggestions I have gotten and I was able to get a better finish.
I think I need to get some retarder because it is hot down here and I am getting a little dry spray, I have to make a pass about 4 time before it becomes a wet coat.
I am going to get a good gun I just dont have the money yet, i also dont know what to get...AAA or hvlp any suggestions ?
I really dont know the benifits between the two different types.
Greetings Rob, what sort of compressor are you using /tank size/ horse power. Do you have a separate oil/water filter?
AAA is air assisted airless, totally different animal.
Devilbiss has a decent set of HVLP guns with various nozzles/tips/caps.
Whoops....didn't see Mastercabmans posting where he asked some of the same ?'s I just did. Sorry for stepping on your toes.
Hey guys I have a 80 gallon Kobalt air compressor that runs off of 220 I don't know the amount of horsepower I can check when I get to my shop.
I just put a regulator that has a water release on it but I don't know if its the same as a oil water trap.
Robert the develbiss hvlp spray guns sounds cool but I'm a little leary on hvlp because of the heavy orange peel i was getting, but i am sure it was because harbor freight.
Do u think it will atomize it well enough with out over thinning to be able to give me a good finish
I work in a shop that finishes over 20 million dollars worth of custom architectural millwork a year. we have finish equipment that ranges in the hundreds od thousands of dollars... we have very expensive spray guns around here and cheap crappy harbor freight ones laying around for little dirty jobbers. I can spray out a panel with the HF gun with the same material that's sprayed in a $600 Sata and get the same results. it's all about tailoring your coating to your equipment and environmental conditions. Yes I may have to use a little more or less air pressure to get it to atomize.... yes I may add some percentages of Butyl Cellosolve to the mixture of a pre-cat or conversion varnish. It comes down to proper technique ( I.E. part distance, overlapping, wet mill thickness )adjustments to your coating..... I've shown my guys here it can be done.... same thing as "Chrome won't get you home"....
I have a hunch Rob that the orange peel is due to user error and partially the fault of your equipment ( yer spray gun ). Not going to slam the HF/Husky spray gun but other brands of guns offer different needles and caps and nozzles that are matched to the material your applying.
An 80 gallon tank is large enough to facilitate the use of just about every spray gun on the market. The main advantage to the HVLP is there is very little over spray; you will realize good transfer efficiency using them or the LVLP.
Not pushing DeVillbis but they are a good step up from the Harbor Freight/ Husky and wont break the Bank. They also make a reasonably priced oil/water separation unit.Both water and oil can wreck havoc on a coating.
If you have time, check out some YouTube videos of HVLP demonstrations. You can get a glass smooth finish, but like everything else, its gonna take the patience to practice and the willingness to experiment.
Buy an Astro HVLP gun from Spraygunworld.com. They are definitely capable of Sata quality finishes and they cost under $100. The 80 gallon is probably 5HP and has plenty of guts. The Astro HVLP are actually high transfer guns that are 65%, but atomize at a better rate than the higher efficiency hvlp guns.
You could buy a cheap gun from Harbor freight and that weeks batch might be okay, but the next weeks are all junk. No quality control.
Thanks guy for the responses Robert thanks for the PM.
I think you guys are right and that a lot of the orange peel is from me not shooting correctly, or tuning the fluid, fan, air flow correctly, retarder etc.
With that being said,
I really dont mind spending some money on a good gun/guns. But I am confused on what to get because there are different types of systems pressure pots, hvlp, lvlp, Airless, Air Assisted Airless. Siphon feed. etc.
I once seen a guy with a AAA and thought wow what a cool gun but for a rookie and a small shop should I buy one or start with a nice hvlp, and should the hvlp be for spraying cars or woodworking? is there a difference?
Or should I go in the middle of the road with a pressure pot, but then I still have to buy a separate gun (I think)
You can either purchase something for the present or purchase something for the future. Thats a call for you to decide.
An all in one website that pretty much explains in basic "talk" the answers to your questions is....CA Technologies.
That should keep ya busy fer awhile.
A major concern for new equipment is how often and how many different finishes will you be using. Also will you graduate to catalyzed finishes. Get an airless, or pressure pot, and you get to clean hoses plus the gun. And then with a deadline if you use catalyzed. Flushing hoses is a big deal. Get a good gun with gravity cup, and all you have to do is clean the gun and cup. I much prefer gravity cup vs suction cup.
I know that everyone has different needs and expectations but I have used most everything over the years and the AAA systems are the best for spraying, the new ones you can turn the air pressure down and get very little over spray. I will admit they have to be cleaned and they need to be used fairly often so seals stay conditioned, but they are the best. If you are only doing a few pieces and only need to mix small amounts of material I use a Sata gravity feed. For woodworking you only need the 100 model with about a 1.8 tip and they spray great, the sata guns use the disposable cup system also which is awesome.