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PROBLEM SOLVING
Preventing a problem is the best way to solve a problem. First and foremost the concern of safety should be addressed. Make sure that all personal protective equipment is used. This includes approved air filtration, spray mask, goggles, gloves and a clutter free air to spray. Make sure there are no ignition source and no smoking in the immediate area of application.
If a problem does occur please refer to the below information for assistance. Also, please feel free to e-mail us or contact your local Executive Distributor for further assistance. For a better investigation of your coating problem please identify some of the points below before determining the cause of the problem.
a. Substrate-wood species, MDF, refinish.
b. Properly prepared- pre-sand, moisture content (@8%-10%), use correct adhesive for veneer.
c. Consistent coating- did you use the same system throughout your application?
d. Application- correct tip size, clean air, serviced air source and pump.
e. Coating Weight. - amount of coats, mil thickness
f. Unusual environmental conditions- humidity, temperature.
1. ADHESION – POOR ADHESION OF FILM
a. Unclean surface-clean carefully with Deft Professional Fast Thinner (030 series).
b. Incompatible systems- always use manufacturer's recommended coating system.
c. Over sanding- never over sand your closed pore hardwoods, never use more then 150 grit.
d. Low humidity- sometimes low humidity can prevent adhesion of film. A technique called busting the grain could help with this problem. Use 80% water and 20% alcohol and lightly mist substrate with a spray bottle. A light sanding may be necessary or a sealer coat to lock up the grains. Always test a small area for tannin bleeds and compatibility.
2. ADHESION- POOR ADHESION BETWEEN COATS
a. Incompatible systems- always use manufacturer's recommended coating system.
b. Overbuild of vinyl sealer-due to the flexibility of vinyl; spray only a 2-3 wet mil coat of Vinyl Tek sealer.
c. Too heavy of a stain (this is the most common cause) - properly wipe surface and allow fully to dry. Use a lower solid stain and least amount of pigment for better adhesion. Also, Lusterdye can be used to achieve a deeper tone.
d. Catalyzed finishes allowed to dry too long- try to finish your catalyzed system within 4 hours.
3. BLEEDING
a. Organic color that bleeds through topcoat-use Vinyl Tek Sealer over Lusterdye or Wood Brilliance to block the bleeding of the stain. Also a Vinyl Tek Sealer wash coat (80% solvent/20% Vinyl Tek) can be used over your Lusterdye to block minimal bleeding.
4. BLISTERING
a. Oil and grease on the surface-wipe down surface with Fast Thinner (series 030) or sand thoroughly
b. Moisture in lines-drain lines periodically.
c. Hot, trapped solvents-use proper reducer when thinning out product.
5. BLUSHING
a. White haze under the surface of clear (excessive humidity over 50%)-add small amounts of Retarder (series 020), no more then 10%.
6. BRITTLENESS
a. If the stain does not dry thoroughly the topcoat could appear brittle -allow stain to dry completely before topcoat.
7. BROWN SPOTS
a. Oil coming through “separator” of supply line-clean the lines after before every shift.
8. BUBBLES-OPEN PORE WOOD
a. Air, gas or vapor is entrapped in the pores-apply a thin, wash coat of sealer (reduce sealer 75%).
b. Do not blow air on to surface directly to clean before spraying-wipe with clean non-silicone rag.
9. CRACKING OR CRAZING OF FILM
a. Excessive coating weight can cause cracks-use a wet mil gauge during application, normally 4 to 5 dry mils (after sanding) is recommended for proper coating weight.
b. Small cracks in the same direction as a veneer (veneer cracking)-check adhesion of veneer to substrate, strip and re-glue.
10. CRATERING/FISH EYE
(The formation of small depressions in the coating)
a. Cratering (crawling) is the tendency of a film to pull or crawl away from areas of the substrate-check area for contaminations; oil on belts, lubrication compounds, etc. Wipe surface down with solvents then use Vinyl-Tek sealer.
b. Old refinished work could have contaminants-strip thoroughly and wipe surface with Fast Thinner (030 series), test an area. If problem continues use a “fish eye killer”.
11. DISCOLORATION
a. Presence of foreign vapors/fumes-investigate the nature of vapors which might be present-it will then be necessary to shield off the vapors from contact with the finish, Vinyl Tek sealer could help with this problem.
b. Using old nitrocellulose products-nitrocellulose finishes tend to amber in color as they age, even in a closed container.
12. FINISH PRINTING
a. Insufficient drying time-allow longer air drying.
b. Too heavy a coat-apply lighter coats.
c. Slow drying or poor drying conditions-see reference to non-drying or poor drying.
d. Improper catalyzation-refer to Carbon Coat or Vinyl Tek Sealer product information sheets.
e. Catalyzed material dried in a cold area, (less then 70°F (cold cure)-make sure drying area is at least 70°F.
13. FLAT SPOTS
a. An absorbent, porous type putty was used that has not been sealed-seal the putty with Vinyl Tek Sealer.
b. Oily or dirty surfaces-provide clean finishing surface, wipe down surface with Fast Thinner (030 series).
14. HAZE
a. Incorrect thinner – use a virgin blend (non-reclaimed) manufactured recommended reducers.
b. Over catalyzation of finish-finish must be removed, use proper amount of catalyst, see Carbon Coat and Vinyl Tek Sealer product information sheets.
c. Both blushing and haze can almost always be removed on finished articles by spraying retarder thinner Over the affected parts if it is not caused by over catalyzation. Test this procedure before stripping surface.
15. LUSTER CHANGE DURING APPLICATION
a. not stirring-stir before and during application
b. the heavier the coating weight the higher the sheen-the average coating weight for topcoats are between 4-5 wet mils.
16. NON-DRYING OR POOR DRYING
a. Humid weather-place in heated and/or dehumidified drying room.
b. Cold weather-maintain a temperature in drying area of at least 70° F to 75° F.
c. Greasy, waxy or otherwise unclean wood surface-clean surface carefully with Fast Thinner (series 030).
d. Failure to stir all pigmented finishes into proper-stir the material thoroughly so that the liquids and
suspension before application. pigments will be evenly disbursed.
e. Improper ventilation-provide ventilation (air movement).
f. An attempt to fill open grain wood by applying too heavy of a coat- use Vinyl-Tek sealer catalyzed under a higher solid product like Carbon Coat, or use multiple coats of Nitro-Pro with heavy sanding between coats.
17. OIL BLOOM
a. Rubbing down with oil before lacquer is thoroughly dry. - allow longer drying time. The oil bloom can be removed by wiping down with an aggressive oil based solvent.
18. ORANGE PEEL
a. Material not thinner out sufficiently-add the correct amount of solvent by measure.
b. Failure to deposit a wet coat-check spray technique overlap properly and trigger at the end of stroke.
c. Spray gun stroke too rapid-take deliberate, slow stroke.
d. Insufficient air pressure-increase atomizing pressure or reduce fluid pressure
e. Using wrong air cap-select correct air cap for the material and feed.
f. Spray gun too far from the surface-stroke the spray gun 6 – 10 inches from surface.
g. Spray gun too close to surface-spray gun should be worked 6 – 10 inches from surface.
h. Overspray striking a previously sprayed-spray detail parts first and end with wet coat. Hold spray surface gun so over spray hits unsprayed work.
i. Poor thinner, too hot-use better grade of thinner for material or add retarder
j. Material not thoroughly dissolved-mix material thoroughly.
k. Drafts-eliminate excessive drafts.
l. Humidity too low-raise humidity of room.
19. MARRING
a. Film not completely dried-allow for more complete air drying.
b. Cold drying area (crosslink/catalyzed coatings)-catalyzed coatings, drying area should be 68° F- 70° F. If not then cold cure (improper crosslink) could occur.
d. Catalyzed finishes installed too quickly after application (within 24 hours) - after 24 hour the catalyzed coating has 75% cure. full cure with wood coatings take around 20-28 days for a full cure. For high-use areas do not install until at
least 5 days.
e. Undercatalyzed- use proper amount of catalyst.
20. PINHOLES/BUBBLING/SOLVENT POP
a. Drafts which cause surface drying before the solvent can break through the surface film in order to evaporate.-find source of drafts. Open windows, doors etc.
b. Fine drops of moisture coming through-clean spraying equipment. “separator” in spray apparatus.
c. Air trapped in open pores of wood such as red oak.-spray a thin wash coat as first coat, or add retarder to finish.
d. Fine bubbles after force drying-be sure adequate solvent flash off time is used before putting the finished part in oven.
21. POOR ADHESION OF HIGH SOLIDS COATINGS
a. High solid coatings do not penetrate an overly sanded surfaces-do not oversand surface. Use a maximum of 150 grit sandpaper and allow stains to dry thoroughly.
22. SANDING/FINISHING
a. Sanding should be done as close to finishing as possible.
b. Most fine woods are not sanded beyond the 150 grit before finishing
c. Sanding new (white) wood should be done with an open coat type paper that is made with silicone carbide or aluminum.-oxide.
23. SETTLING
a. Over reduction or improper thinner-follow thinning instructions.
b. Too rapid thinning-add thinner gradually, stirring constantly.
24. SPOT DRYING
a. Unclean surface-carefully clean wood surface with volatile solvent prior to coating.
25. WHITE SPOTS
a. Water mixing with the lacquer either through the separator or spraying on a damp surface- bleed lines before every shift.
b. Flatting paste not mixing in-stir thoroughly and strain material if necessary.
26. WRINKLING
a. Caused by applying too thick a coating, this prevents uniform drying of the coatand thus results in formation of ridges and furrows-Material should be applied in even uniform coats. Try to prevents spotty drying by removing any drafts.
SPRAYING PROBLEMS
1. EXCESSIVE MATERIAL USAGE
a. Not triggering the gun at each stroke- trigger after every stroke.
b. Gun held at wrong angle to surface-hold gun at right angle to surface.
c. Gun held too far from surface-work gun 6 to 10 inches from surface.
d. Wrong air cap or fluid tip-use correct combination.
e. Depositing material film of irregular thickness-learn to calculate depth of wet finish film.
f. Air pressure too high-use least amount of air necessary.
g. Fluid pressure too high-reduce pressure.
2. LEAKS- COATING LEAKS FROM SPRAY GUN
a. Fluid needle packing too tight-loosen nut and lubricate packing.
b. Fluid needle packing dry-lubricate needle and packing frequently.
c. Foreign particle blocking fluid tip-remove tip and clean.
d. Damaged fluid tip or fluid needle-replace fluid needle with correct size for fluid tip being used.
e. Broken fluid needle spring-remove and replace.
3. LEAKS- COATING LEAKS FROM FLUID NEEDLE PACKING NUT
a. Loose packing nut -tighten packing nut.
4. NO PRODUCT FROM SUCTION CUP
a. Dirty air cap or fluid tip-remove air cap and fluid tip and clean thoroughly.
b. Clogged air vent on cup cover-remove obstruction.
c. Wrong air cap-ascertain and use correct set-up.
d. Leaky connections on fluid tube, air cap, or fluid-check for leaks and repair tip
5. SAGS AND RUNS
a. dirty air-cap and fluid tip-clean air cap regularly
b. gun strokes too close to surface- 6 to 8 inches from the substrate.
c. trigger not released at the end of stroke- release after every stroke.
d. material too cold- heat material by approved methods.
e. coating applied too heavily- use wet film thickness gauge to determine coating weight.
6. SPRAY FOG
a. Wrong solvent blend-use a slower evaporating reducer.
b. Atomizing air pressure too high-use least amount of compressed air necessary.
c. Over reduction of material-use less reduction.
d. Gun held too far from surface-hold gun at proper distance, usually 6-8 inches.
e. Spraying past surface of the product-release trigger when gun passes target.
f. Wrong air cap or fluid tip-refer to gun manufacturers specifications.
g. Fluid pressure too low-increase fluid pressure.
7. STREAKS
a. dirty air-cap and fluid tip-clean air cap regularly
b. gun strokes too close/far to surface- 6 to 8 inches from the substrate.
c. insufficient lapping of strokes-follow previous coat with 50% overlap.
d. too much air pressure- use the least air pressure necessary.
e. split spray-clean fluid and air-cap.
The above information is not binding, use advice at own risk.
TECH SUPPORT
proservice@deftfinishes.com
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