Q.
After many years of sending our work out to a subcontractor for finishing, we are going to try doing it ourselves. We are very new to this field an would like input on the following:
Waht type of spray system is better, HVLP or conventional? I'm leaning to HVLP for its low overspray; we are working in a very small area and this is a major concern. We want to start small, but want the right equipment.
Also, what type of stains are best to use on wood veneer panels? Years ago I'd mix my own, with Japan colors and mineral spirits. Is there anything better on the market now?
Finally, what are some of the better topcoats to use besides regular lacquers?
Next to the Airmix would be a conversion gun from Asturo because it operates on a small amount of psi and cfm, compared to many air-hog conversion guns, and even compared to more efficient conversion guns like the Sharpes and many others.
As for stains, you are better off letting your supplier spend money on research and development to produce a product that will work nicely with their topcoats. If you stay within the supplier's recommended finishing systems, they will help dig you out of a hole, and they will also help you to develop finish schedules that they spec and that you can market to your customers.
The only thing that you should be mixing is colorant into a clear stain base, or one stain with another. Measure your amounts and mix ratios with a good scale, and write down all your finishing steps with accuracy, and you will have finish products that are consistent and predictable.
Make step boards of each finsih step, labeling each step on the backs of each board. Protect them and use them periodically to make new ones. These should be your color standards so that your finishing people, as they change over time, will know what each finish should look like, and each step along the way. This will also make troubleshooting much easier than trying to guess what steps you took to get you into the failed finish that you have.
As for topcoats, that is determined by what you want to offer to your customers. Durabililty, performance, wear, enviromental concerns (OSHA and EPA), reversibility, ease of application, etc. all play a part in detrmining which way you want to go. This is an area best discussed with your finish supplier. But the supplier has to be top notch and capable. Anyone can sell a product. But not everyone will have full working knowledge of how that product is to be used, and what can happen from different types of misuse. Look for a supplier of OEM finishes.
Better topcoats beside lacquers are usually post-catalyzed finishes, such as catalyzed lacquer, conversion varnish, catalyzed polyurethane and polyester. Then there are classes of waterbornes that are interesting.
I would find out what the guys that you were having your stuff outsourced to were doing. Who was their supplier of finish material and equipment? Reputable finish material and equipment reps provide a wealth of knowledge. I have a few that I trust very much and more than welcome their opinions and/or recommendations. The best possible way to set this up properly is find an equipment rep, a coatings rep, and have a meeting to discuss what direction you want to take. There may be lots of ideas, but work toward the most feasible process for you.
Also, most reputable finish reps are up to date with what the market trends are for your industry and can be a lot of help. Just don't let them add something just to sell more material. Take into consideration cost, production constraints, and the talent of your people.
There is no need to use a catalized product when a regular nitrocellulose (NC) lacquer is all you need for your product. Keep in mind that all NC lacquers are not created equal and they are much more user friendly and idiot proof than a post or pre-cat system.
Precats are fine for furniture and other low-wear items; however, a desk top, is that a low-wear item? Maybe not. So do you spray some pieces with precat and some with postcat? You get my point. I spray 90 percent of my work with catalyzed lacquer and conversion varnish. Is it overkill? Maybe -- and maybe not. Do I have problems with blushing? No. Do I have problems with durability? Very rare and most of the time it's my fault.
Another issue is the percent of solids in a finish. High-building finishes such as catalyzed coatings are great, however, you are limited in the amount of finish you can apply to a piece. Normally, it's two to three coats and no more than 5 to 7 mil dry.
The best thing to do, as recommended by the previous posts, is to find a supplier that you're comfortable with.
