Monday 17 March 2014

Water Based PU Finishes for Wood

We all need a cleaner environment and water based variants in paints are definitely a step toward this. Water based products such as water based polyurethane for wood are eco-friendly in that they have very low percentages of volatile organic compounds. Not only are these products environmentally responsible, projects can also be turned around faster. Water based systems have faster drying times and are easier to apply - They need not be sprayed. No solvents required, only water is required for thinning and cleaning - thus posing a very low health hazard to applicators. Polyurethane has the property of having good abrasion resistance, good UV stability and creates an impermeable water barrier. Too good to be true? Well the future of paints is here - water based polyurethane coatings for wood. Excellent for outdoor wood and indoor furniture.

The finish of these products is pleasing to the eye and the matt finish is soft to the touch. It gives the wood a natural, well finished and rounded look. 

 Let us look at the application procedure for Water Based Polyurethane products :

Materials

. Random Orbital Sander
. Velcro Discs for Orbital Sanders 5" or 6" - Open coated type - Grits 120, 150, 180, 220
. Sheets for Hand Sanding - Open coated type - Grits 120, 150, 180, 220
. Scotch Brite Hand Pads or Steel Wool.
. Brush 2", 3"
. Felt Roller 4"
. Putty Knives 2", 3", 4"
. Dent Filler
. Wood Filler
. Water Based Polyurethane Base Coat
. Water Based Polyurethane Top Coat - Matt or Glossy.
. Clean potable water.

Application
. Sand the veneer/wood along the grain with papers of grit 120/150. An orbital sanding machine can also be used with the same grits.
. For woods with carving or grooves, Scotch Brite Handpads or Steel Wool must be used for sanding.
. Brush on a coat of wood preservative along the grains for exterior woods and allow to dry for 3-4 hours.
. If the wood has been polished previously using traditional Spirit based polish, apply a coat of wood filler using a putty knife or muslin cloth after sanding and wood preservative application. Allow to dry for 3-4 hours.
. Using a dent filler, fill major dents and imperfections using a putty knife.
. Apply the 1st coat of interior/exterior sealer by spray, brush or roller depending on the depth of the grains, along the grain. For 2K systems, the hardner has to be mixed in the given proportion - Be sure to allow for sufficient maturation time and to use the material within the given pot life. Dilution of up to 10% is allowed using clean water.
. Allow to dry for 4-5 hours.
. Sand the 1st coat using 180/220 grit sand paper. A white powder as a result of sanding is an indication of successful application and curing of sealer.
. Apply a 2nd coat of sealer and repeat the process followed for the 1st coat.
. Once sealer coats are completed, apply 1st coat of topcoat matt or glossy by spray or roller. For 2K systems, the same precautions apply. Dilution of upto 10% is allowed using clean water.
. Apply a 2nd top coat after 5-6 hours.
. Buffing operations can be taken up for glossy topcoats after about 12 hours and within 4 days from the time of application of the 2nd topcoat.


We have well preserved wood with excellent aesthetics, Eco-friendly too!!!!

Let us look at some products which are already available at our store.

Asian Paints Aquadur PU


Aquadur Interior
Aquadur is available in interior and exterior variants.
. Low VOC.
. Child safe.
. Can be brush, roller or spray applied.
. The Aquadur range consists of products such as wood preservatives, wood fillers, dent fillers, wood stains, sealer and top coat.
. Top coat is available in the options of gloss and matt finishes.
. Single component, no need of adding hardner seperately.



MRF Aquacoat 1K and 2K
MRF Aquacoat 2K
. Interior variant available in single pack system(1K);
 exterior variant in 2 pack system(2K).
. Low VOC.
. Solvent free.
. Child safe.
. Can be brush roller or spray applied.
. Sealer is available in 1K and 2K systems.
. 2K system gives an extremely hard film.
. Matt and Glossy finishes.





Available in store now, at

Shree Venkateshwara Traders
712, Modi Hospital Road,
West of Chord Road, Mahalaxmipuram
Bangalore 560086

9036092531 - Namit Bhulani
080 - 23592523 - Landline

venkateshwara.traders@gmail.com

Shop online @ www.paintnhardware.com

3 comments:

  1. Excellent articles Namit, well research, informative and much appreciated.

    In your opinion which pu-based wood polish is the most superior for external applications like windows etc, in coastal areas like Chennai.

    I have been advised that MRF's Wood Coat or Aquacoat 2k are quite good.

    Thank you in advance for your assistance.

    With kind regards
    Rasananda

    Regards,
    Rasananda | rasananda@hotmail.co.uk

    ReplyDelete
  2. Hi

    For exterior purposes such as windows and doors, water based pu's are highly recommended. MRF Aquacoat 2k is a top product.

    For improved protection for you external wood, a wood preservative is extremely important. Asian paints aquadur clear wood preservative is available in the market. It must be applied onto the wood after sanding. It provides protection against sunlight and water.

    Also staining your wood using a wood stain after applying wood preservative will vastly improve the performance of your wood coating.

    If you dont mind could you provide me details about yourself and your site.

    Regards
    Namit

    ReplyDelete
  3. Thanks for your prompt response Namit, and for your detailed advice.

    I was quite impresed with your blog, and the subjects you have covered. It is refreshing to see someone have passion in their vocation, which you obviously do.

    Do you supposed the stone sealers you wrote about would work to give a wet look on honed kadappa used in bathroom shower area? How much do they cost per litre?

    Also, we have already applied 2 coats of pu based sealer from MRF. Can we still apply the Aquacoatt 2k over it?

    We are finishing a small project in the south.

    Thank you for your assistance.

    With kind regards

    Rasananda

    ReplyDelete