Important Information for Wood Polish Work.

Wood Polish: PU / Melamine / Lacquer / What / How / Dos / Dont's.

Wood Polish is one of the most playable areas where people who do not have any idea , get scammed by Painter and Uncouth Paint Retailers.

People spend Lacs of Rupees in getting the best wood for our homes. You take lots of suggestions and check out the quality of wood at various places before making a purchase of wood.But what happens when it finally comes to wood polishing ? Following are some tips for a layman to understand.


PU Polish :
Suited for Exteriors and Interiors. This system will last a long time in exteriors if done the way it is to be done, but sadly that's not the case.

It comes in various brands such as Asian Paints, Berger, Akzo Noble (ICI Dulux), Jeevanjor, MRF and many more.

It is commonly available as Solvent (Thinner Based) in Two Component System with Base and a Hardener. Usual Ratio for which is 80:20 or 90:10. (Base : Hardener)

PU Polish comes in Matt , Glossy or Semi Gloss Finish

Problem areas in method of Application : 

1. Painter using Lac Dana as a base and for setting color. As Lac Dana is not UV resistant , the PU finish will come off as it will peel off due to Lac Dana base preparation. Lac Dana degrades faster in sunlight. Instead of lasting 3 or 4 years the PU Polish will come off within a Year or so of the application.
2. Painter using NC Sanding Sealer instead of PU Sealer , to save labor as it is easy to sand and also cheaper instead of PU Sealer . This leads to PU Polish coming off in Exterior conditions due to degradation in Sun light. NC Sanding sealer should not be at all used for application of PU Polish in Exteriors. Again, it won't last more than a year in sunlight if the polish base is made by using "NC Sanding sealer".
3. Improper Thinner being used. There is a very important reason why companies provided specific thinner for specific Polish Systems. To cut cost Painters use local quality NC thinner for PU Polish , this may lead to improper build up of film and effect  the true finish on final curing. As the specific thinner for each system, whether it is PU or Melamine is designed to support the proper dissolution for material and also proper cross linking (curing or drying) to occur for expected quality of  finish to form.

Cost : (In the year 2010)
PU Systems : Anywhere from  Rs 400/-  to Rs 650/-
PU Thinner : Rs 120/- to Rs 150/-
PU Sealer : Rs 400/- to Rs 500/-
(Prices are approx Please check current pricing)


Coverage of PU system Per Liter : 25 to 35 Sq.ft Per Liter
Application : Spray Application Only. In Some cases may be hand applied but this compromises on the finish.


PU Polish :  Latest Innovations.

For the last couple of years Water based PU systems are available in the market of Imported varieties and also now locally manufactured by some companies.

The water-based PU system only required Water to be dissolved and does not need any hardener . So it does not get wasted also if it is not sprayed after dissolving in water.  

This kind of PU system is especially suggested for Outdoor use like main gates and Wood panel which are in total exteriors.

Can be sprayed, brushed, roller applied and hand applied

The best is Waterbased PU systems have very low VOC or harmful compounds. As there is no solvent use, there is no smell also.

Specially suited if you have kids in the family and Polish work has to happen. 

All about White Cement Putty. Good or Bad.

Commonly known as Birla Putty, as Birla White Cement was the initiator of the Product, it is manufactured now even by paint companies and there are many local players now in the market with this kind of product.

Market price range of Local Variables start from Rs 325/- to Rs 500/- for 20Kg Pack to branded products like Birla or JK or others

So some common brands are

1) Birla Putty

2) JK White Putty

3) Jensolin Putty by Jenson & Nicholson

4) Asian Paints White Cement Putty

5) British Paints, and many more, like SIKA ,  Roofit etc.

Common Packaging Available: 20 Kg packs (with Rs 40 to Rs 50 token inside), 40 Kg Packs (Without Token) 

 

About the Product

Ingredients: White Cement + Polymers + Fillers to make it smooth and reduce the need of curing.

The product has now become very common and almost every new construction be it private home or commercial construction, the market has adopted the product blindly.

The Perception is that it provides a very smooth surface and reduces the consumption of Paint.

Some of the Companies are also promoting and giving huge advertisement that the putty application protects your paint!

In Reality.....

1. The over smoothness of cement putty surface reduces the consumption of the paint. This means that it also reduces the Dry Film Thickness of the Paint when applied on the Putty. What it effectively does is that the minimum recommended quantity required for the paint to perform specially on the exterior surface per square feet is reduced to half.   So it also reduces the life and performance of the paint. As the minimum material required to form a protective layer to withstand Sun Rays, Rain and the air pollution effectively is not there. Due to the over smoothness of the Putty surface the Consumption is only 40% of the recommended material required for the expected performance of paints.

2. Cement Putty does not protect your paint from of moisture ingress in the Surface !    Some of the Interior Design Magazines carry full page ads screaming that the White Cement Putty protects your paint from moisture and prevent it from peeling off !
3. The fact is, paint peels off whenever when there is moisture in the surface of the wall, which may be due to waterproofing issues or absorption of water in the wall due to proximity of water. Now Cement putty itself will not come or "De-Bond" due to moisture, but the Paint, which forms a non-breathable layer will always peel off.  No matter what the surface is i.e. White Cement Putty or Simple Putty of POP. it wont matter. If there is moisture in the surface the paint cannot survive, be it of any quality.   So the false perception is created that use of white cement putty inside the structure will keep the paint safe. 

No Doubt the putty application does make walls look smooth, but this is more relevant in the case of exterior walls. 
On the interior walls, no cement putty application  can ever match the POP finish.

Even if one has to apply putty following care should be taken.

1. Properly curing the surface before application is a must. Especially in hot regions. The Surface should always be moist before application of Putty. Sadly, in 95% cases the curing is not done.
2. It will be always good to do one curing after the application of Putty coat.
3. One coat is enough for the surface to be sealed as the second and third coat of putty makes a super smooth surface which is detrimental to anchoring of the exterior paint and thus reduces its performance.

Suggestions for Long Life of Paint on Exterior Walls

1. Spend 50 Paisa extra on plaster to get a leveled and smooth plaster in two layers.
2. Add waterproofing additive to plaster to make it watertight and this also improves the finish of the plaster.
3. If you have applied putty already , then do not go for the high end paint like Asian Paints Brand :  Apex Ultima or , Weathershield Max by ICI Dulux (Akzo Noble) etc. , as you will not get the expected performance in terms of life of paint or properties like crack bridging etc.   Go for normal variety like Simple Apex , Weathershield of normal quality.  As there is quite a difference in the price of the qualities of paint. 
4. If white cement putty is applied, then it should be painted within one week, as after 15 days the Putty self-seals due to chemicals mixed in it to make it smooth. There are also lot of cracks generated . 
5. If Putty has been applied for more than 20 days and left unpainted then its surface should be thoroughly sanded down with 80 No Emery Paper.

Facts

1. Cement Putty Does not increase paint life. Rather reduces it in cases of Exterior use.
2. Saving in terms of reduced consumption of paint is nullified by the increased cost of putty application
3. Cement Putty application will nullify the best qualities of premium exterior paints like Apex Ultima by Asian Paints or Weathershield Max or any other premium paints of existing products
4. It is more practical to invest in higher quality of Paint rather than the application of Putty on exterior walls.
5. Interior wall finishing will come much better than if you go for a POP finish as it would almost be the same cost as Cement putty while giving many times better result.
6. If you use Cement putty for interiors then you won’t be able to use High End Plastic Paints like Dulux Velvet Touch , or Asian Paint Royal as all the waves in the wall surface will be amplified and the walls will look bad when the lights will be turned on. 
7. All these high quality paints look good only on a leveled POP surface which a white cement putty can never achieve. 
8. Cement Putty Layer Thickness is hardly 1.5 mm while POP is up-to an Inch Thick which can cover all kinds of undulations of the plastered wall.

My Take: Yes, Cement Putty Should be avoided from any sensible finishing system.