10 Basic Rules for Avoiding Common Problems

In-the-Container Problems

Application Problems

Film Property Problems
10 Basic Finishing Rules for Avoiding Common Products Finishing Problems
1. Be sure the material you are using is adequate for the purpose intended. Proper testing of finished samples or pilot lots will offset future complaints.

2. Make routine inspection of material for working properties before throwing on production line. This prevents shutdowns.

3. Keep equipment in working order. Daily inspections should be made. Dip tanks should be checked for viscosity, gravity, performance; spray lines should be kept clear, etc.

4. Be sure that the product surface is properly cleaned and in suitable condition for painting.

5. Reduce paint in accordance with manufacturerÕs instructions. Strain reduced material into spray tank or other production line equipment.

6. Practice routine inspection. Faulty production should be apprehended quickly to prevent accumulating rejects.

7. Use good housekeeping measures. A clean shop produces clean work, and reduces lost time caused by accidents, fire, etc.

8. Be aware that changes in weather often require adjustments in handling procedure, such as change of reducer, drying time before packing, etc.

9. Check on stock rotation. Use lots in order received, to prevent leaving extremely old materials in stock.

10. In refilling leftover material, strain into clean containers, fill containers to the top, and close tightly so that there will be no air leakage into the package. Label and date.
In-The-Container Problems
Problem Cause Remedy
Settling - Over-reduction or improper thinner - Following instructions
- Too rapid thinning - Add thinner gradually, stirring constantly.
Gelling - Any material which will dry in the presence of air at normal temperatures will tend to take on body by virtue of oxidation with takes place. - If bodying of the material has not proceeded to the point where there is livering action, it is often possible to bring the thickened particles back into solution by addition of a stronger solvent of the same general type or class.
- Even a straight baking type enamel will tend to take on additional body due to evaporation of solvents. - Add proper solvent to bring liquid to proper viscosity and body.
- In the more advanced stages of oxidation, a livering action often occurs which is aggravated by the too-swift addition of extra thinner. It should be remembered that thinner should always be added slowly and the mixture stirred at the same time. - If a definite livering has occurred, it is not easily feasible to reclaim the material. Sample should be submitted to your Diamond Vogel representative or to Diamond Vogel Paint Co., Inc., 1020 Albany Place S.E., Orange City, Iowa 51041
- Use of improper solvent. - Use recommended thinner.
Note: The primary cause of excessive bodying is, in most cases, improper handling of dip tank or other storage facilities. A method for keeping all storage tanks tightly sealed should be arrived at and carefully adhered to.
Skinning - While it has been possible (to a large extent) to minimize skinning, it is something which will occur to a varied degree whenever air-drying enamel is exposed to the air. Skinning can be almost entirely eliminated in baking enamels where tank conditions are reasonably good. - Make sure that containers in which the material is stored are airtight. Dipping tanks should preferably have an oil or water-sealed cover, and cover should be in place whenever tank is not in use. Whenever conditions are such that skinning cannot be overcome by normal means, consult your Diamond Vogel representative or write to Diamond Vogel Paint Co., Inc., 1020 Albany Place S.E., Orange City, Iowa 51041
Note: to avoid skinning during storage of open container, or during long disuse of dip tank, cover remaining contents with a small amount of reducer before sealing.

Application Problems
Problem Cause Remedy
Slow Dry Time - Humid Weather - If possible, place in heated drying room.
- Cold Weather - Maintain a temperature of at least 65 degrees F. 76 degrees F. is desirable for normal drying.
- Absorption of drier by paint material. - While it is a problem of formulation to avoid possibility of drier absorption, there are occasions when the best formulated products are apt to face that difficulty. Remedy is to add up to 3% of the proper drier.
- Greasy, waxy, or otherwise unclean paint surface. - Clean surface carefully with volatile solvents. If metal, use special metal treatment, such as Metal-prep, Galva-prep, etc.
- Failure to stir all pigment of pigmented finishes into proper suspension before application. Failure to stir properly unbalances formula of applied material and often will cause poor drying. - Stir the material thoroughly so that liquids and pigment will be evenly dispersed.
- If application is over a stained surface, there my be some dye in the stain used which tends to prohibit drying. - Use the proper stain.
- Improper ventilation. - Provide ventilation.
- An attempt to fill rough wood or metal by applying a heavy coat retards thorough drying. - Do not attempt to use finish coat as a surfacer. Apply only a full covering coat.
- Unclean surface. - Clean carefully with volatile solvent or, if metal, with a commercial metal cleaner.
Poor Hiding - Over-reduction. - Add fresh, unreduced material to that which has been reduced.
- Application on very hot, smooth surface which tends to cause film to flow off. - Use a faster evaporating solvent.
- Pigment not properly stirred into suspension. - Stir thoroughly to properly distribute pigment.
- Too-slow evaporating solvent, causing too much flow. - Use faster evaporating solvent.
- Improper atomization. - Adjust spray equipment.
- Low film thickness. - Apply more paint via more passes with spray gun, higher solids (less reduction), faster thinner.
Lack of Flow - Insufficient reduction. - Reduce according to instructions.
- Use of solvent with too fast an evaporation rate. - If fast evaporation is due to local weather conditions choose a slower evaporating solvent than originally recommended.
- Improper atomization of spray gun. - Adjust spray equipment.
- Application of too thin a film. - Apply more material to surface.
- Draft conditions. - Find reducing solvent or blend to provide proper flow in a draft or eliminate the draft.
Color Separation - Poor agitation. - Stir thoroughly to properly distribute pigment.
- Too thick a film. - Reduce film thickness.
- Too slow reduction solvent. - Use a faster solvent.
Dusting - Wrong solvent blend. - Usual remedy is to choose a slower evaporating thinner.
- Excess spray pressure. - Reduce pressure.
- Over-reduction of material. - Use less reduction. Add fresh material to that which has already been over-reduced.
- Gun held too far from surface. - Hold gun at proper distance from work (usually 6 to 10 inches).
Sagging - Sagging is caused by either over-reduction or by use of too slow a solvent. - Use the proper solvent consistent with the general nature and temperature of the surface to be coated.
- Application of too heavy a coat. - Do not apply so much material to the surface.
- Draft conditions. - Eliminate draft.
- Strong sunlight causing top drying and consequent later slippage of film on vertical surfaces. - Avoid application in strong sunlight.
- Uneven distribution of spray coating. - More careful application by proper handling of spray gun.
- Jerky operation of mechanical equipment for withdrawal from dip tank. - Repair or redesign equipment
- Cold weather - Use faster evaporating reducing thinner or bring room temperature up to 75 degrees F.
Bleeding - Organic red pigments or various dyes used in stain or undercoats have not been sealed properly. - Best remedy is to avoid use of bleeding colors. Where bleeding colors have been used, a shellac-type sealer usually tends to seal the bleeding better than varnish or lacquer-type sealers.
Orange Peel - Use of improper solvent for prevailing temperature condition. - Choose a solvent which will allow greater flow.
- Improper handling of spray equipment. - Adjust air pressure and fluid flow and be sure that gun is held at proper distance from work.
- Application of too thin a film, not allowing proper flow. - Apply heavier coating.
Lifting - Sometimes strong solvents tend to react with preceding coat. - Be sure that the undercoats are thoroughly dry. Use primer recommended. Use thinner with lowest solvent strength which will still act as steady diluent.
Poor Electrostatic Wrap - Dry over spray. - Use retarder such as 150 reducer.
- Low polarity. - See equipment manufacturerÕs recommendations for reduction of paint and polarity requirements.
- Electrical. - Check power at transformer and gun.
Bubbling / Pin Holes - Drafts which cause surface drying and force the solvent to break through that surface film in order to evaporate. - Avoid drafts.
- Fine drops of moisture coming through separator in spray apparatus. - Clean spraying equipment.
- In the case of wood finishing, either the solid wood or the veneer may be improperly kiln dried, or may have absorbed excessive moisture. - Only solution is to cure or dry wood properly.
- Thinner evaporates too fast. - Use slower thinner.
- Porous surfacer or fillers. - Use tighter surfacers or else seal it before applying finishing coat.
- Incomplete drying of filler. Strong solvent in finishing coat tends to react with undried filler. - Use a faster drying filler or allow greater drying time or arrange to dry at elevated temperatures.
- Spots of grease on surface. - Clean surface carefully.
- Material applied while frothy, following violent agitation. - Allow froth to subside before applying.
- Lack of wetting of the surface by the enamel. - Wipe surface to be sprayed with a solvent-saturated cloth before application of the next coat.
Washing of Film - In some dip operations, faulty ventilation in the hood above the dip tank allows a concentrated collection of solvent vapors. This reduced the film on the object which has just been withdrawn from the dip tank, thereby causing the film to wash or flow off the finishing surface. - Provide proper ventilation over dip tank.
- Faulty ventilation in oven causes concentration of vapor. - Provide proper ventilation.
- Wash caused by cleaning solvents remaining in crevices. - Be sure surface is clean, as well as all crevices. Change angle of drain.
Cratering - Silicone contamination. - Locate source of contamination and eliminate it. Check wipers, belt dressings, lubricating greases and oils, hand creams, metal and wood polishes, etc., as possible sources.

Film Property Problems
Problem Cause Remedy
Dirty or Seedy Finish - Unclean conditions of application.
1. Dust in paint room.
2. Dirt in air or paint lines of spray apparatus.		 - Cleanliness.
Rearrange equipment so that any spray dust from booths does not reach drying chambers.
- Improper solvent which tends to throw resin out of solution. - Use the proper recommended thinner.
- Material has been subjected to extreme cold which tends to throw some particles out of solution. - Allow material to reach 75 degrees F. before applying. If still seedy, consult your Diamond Vogel representative.
Poor Adhesion - Certain types of metal such as galvanized iron, cadmium, and zinc are difficult surfaces. - If normal methods of metal preparation do no overcome adhesion difficulties, send full particulars, with samples of metal to your Diamond Vogel representative or to the Diamond Vogel Paint Co., Inc., 1020 Albany Place S.E., Orange City, Iowa 51041.
- Unclean surfaces. - Clean carefully with volatile solvent, or it metal, with a commercial metal cleaner.
- Lack of film toughness, produced by over-addition of drier. - Checks results against fresh material to which no drier has been added.
- Mar-proofer or wax in previous finish or in first coat. - If refinishing over mar-proofed old finish, clean carefully with strong, volatile solvent. If mar-proofer is in the first coat just applied, it will be necessary to choose another type of undercoater, or else a mar-proof finish which will allow application of another coat over without loss of adhesion. (Consult your Diamond Vogel representative).
- Sometimes the finish coat and the primer used are not meant to be used together, and the solvent in the finish coat practically lifts the primer from the surface. Even though film will dry and have good appearance, primary adhesion has been ruined. - Make sure that the proper recommended primer and finish coat are used together.
- Overbaking, which accelerates loss of flexibility in the film. - Check oven and bake according to instructions.
Poor Inter-Coat Adhesion - Primer and enamel not recommended for use together. - Use properly recommended system.
- Primer dries too hard--or glossy--due to inherent drying quality or long aging prior to application of finish coat. - Roughen primer with sandpaper or steel wool. It may even be necessary to use a reducer of higher solvent strength in the finish coat in order that a tooth can be obtained in the primer film.
Poor Flexibility - It is often difficult to differentiate between "lack of adhesion" and "brittleness" in evaluating some film failures. Other than inherent brittleness or lack of adhesion in a finish, the cause for either difficulty will be the same. - See "Poor Adhesion," problem.
- Improper baking. If complete polymerization of film has not been effected, brittleness may follow. - Check oven operation and follow baking instructions.
Poor Hardness (Mar Resistance) - Film not completely dried. - Allow for more complete air-drying or baking.