Sunday, May 13, 2018

Pu based finishes: Asian Paints Aquadur PU

The following post documents my experiences using Asian Paints Aqudur PU.

The advantages of Asian Paints Aquadur PU
  1. This is a brand that is available near home. That is why the choice of the brand. 
  2. It is water based: dilution with tap water and washing with water. What more could one ask for!
  3. Fast drying: Prevents dust build up 
  4. Very easy for kids to use. 
  5. It does not darken the wood after finishing. When wood is wet, it appears darker. This is what happens when one uses a finish like the Woodtech PU or Touch wood. However with the Aquadur PU, the wood will retain its natural color. This is important if you want to retain the lightness of the wood to contrast with a darker wood. 
Cost 

On the more expensive side. It may cost about Rs 500 or  more per liter

Disadvantages
  1. Leaves a slight milky hue as the layers build up. This will be more visible on a dark wood. With one coat on a light wood it is not really a problem. 
Application. 

  1. Sand and clean the surface. 
  2. Apply Aquadur PU base coat
  3. Lightly sand with 400 grit paper. Apply a second coat if needed and sand
  4. Apply the Top coat o Aquadur (matte/glossy)
  5. For a matte effect add more coats to get it more matte (not intutive but that's the way it is)
  6. For a glossy effect add more coats to get it more glossy. 
  7. The more the coats, the more the milky hue. 
  8. Stop when you feel you have got a good enough finish. 
Cleaning
With tap water. I do this in the sink. All brushes and bowls can be cleaned easily. This is the main advantage of the PU. 


How I use it.
This is my go to finish when I make toys. It is easy to use. I set up the painting station on the dining table, (with due permissions and through proper channels) with a layer of newspapers, and over a couple of evenings  the finish is complete. Washing brushes is very easy.
I also use this for a quick finish (only the base coat) when I just want to protect a wood, but am not particular as to how the wood should look. For example a quick project with plywood can be covered with the base coat, just to protect it. Once this is done the wood can even be wiped with a wet cloth for more coats when I have the time. 











Ferm Scroll Saw: A review

Item: Ferm Scroll Saw SSM 1005

My experience with it: I have bought four saws as of today

Cost: Approx Rs 8000

Pros:

1. The best scroll saw available in the Indian market today in my opinion
2. Wide availability online
3. Simple construction: Easy to dismantle
4. Powerful motor
5. Tiltable table

Cons:

1. Pinless blade changes are very difficult
2. The lower half of the pinless adapter falls into the machine when the blade breaks and the sides have to be opened out to fish it out.
3. Brittle cast iron. Two of the four scroll saws that I bought were damaged in shipping and the cast iron was broken. This can be easily welded as it is iron though.

Essential tweaks.

1. When you face the machine, remove the left housing. This can be done from above with a screwdriver.
2. Make a simple pin-less adapter to facilitate pin-less blade changes
3. Fix the machine on the table with long bolts, going through the rubber. The rubber cushions the machine and the long bolts through the table you use prevent the machine from wandering.
4. Remove the safety plastic and the arms of the safety plastic. Wear specs instead and leave room for a custom made pin-less adapter
5. If for any chance you are removing the motor, get rid of the right housing also. This is possible only after removing the motor.

Possible problems if your machine is noisy

1. Check to see if the allen head bolts near the motor shaft are loose. If they are tighten them.
2. Check to see if the upper arm of the scroll saw is touching the protective housing.

Final conclusions 

I feel the ferm scroll saw is worth the money in the Indian market. It does suffer from some serious design flaws, but nothing that you cannot circumvent with a little workshop help. If you have a woodworking workshop and are comfortable with opening it up, it can be converted into a lean and mean machine.

PU based finishes: Asian Paints Woodtech PU

I have experimented a lot with different PU based finishes. What I am going to describe below is my experience with Asian Paints Woodtech PU.

The reasons why I selected Woodetch PU

  1. Fast drying: Dries in about an hour. As I do not have access to a dust free location, the longer a finish takes to dry, the more dust gathers. Besides, I can put on one coat on one side, do something else and finish the other sides in a matter of about two hours. 
  2. The only finish available near me; Well I really do not have much of an option with regards to finish in my area, so I have been more or less forced to use PU. 

The other options

  1. Asian Paints Touch wood: This is cheaper. However it takes a longer time to dry, and therefore will pick up more dust
  2. Asian Paints Aquadur PU: Water based and very easy to use, and fast drying. However as it builds up it leaves a white milky hue, that I do not like. More about this finish later. 
What you will need
  1. PU Sealant : 1 Liter
  2. PU thinner/NC Thinner: at least 2 L 
  3. PU Woodtech Matte/Glossy 1L
  4. Small spoon
  5. Bowl to mix
  6. 2 inch paint brush 
  7. Waste cloth
  8. Bottle to collect waste
  9. Time
Application Procedure (How I do it) 


  1. Clean and sand the surface to be finished.
  2. If you are worried about insects, apply some insect repellant. I use Terminator (made by Pidilite). It is supposed to have some herbal extract that keeps insects away. This will need to dry overnight. Be liberal with this. 
  3. Apply Asian Paints PU sealant. Mix 4 parts of the sealant with one part of hardener.   I use a brush.  This has to be diluted about 1:1 with PU thinner. As PU thinner is quite expensive, I get away by using NC thinner. This dries rapidly. 
  4. If time permits and if you have patience to spare, sand with a 400 grit paper lightly and apply a second coat of PU sealant. The sealant takes about 1 hour to be dry to touch. It will be ready for the next coat after about three hours or so. I put on one coat in the morning before I get to work, one in the evening and one at night. Sand with 400 grit paper. 
  5. Mix 4 parts of PU varnish with 1 part of the hardener. Dilute this with about 1:1 thinner to get it to a consistency that can be painted. 
  6. Paint this on the surface. The varnish dries very fast. You may not be able to go over what you have already brushed on. Make sure there are no bubbles and drip marks. They will be a pain to take off later. 
  7. Let this dry for about to to three hours. Lightly sand with 400 grit paper and paint on the second coat. 
  8. Usually two coats will suffice. Stop when you are satisfied. 
Some precautions. 
  1. As the varnish dries very fast, the brush will feel sticky if your paint session takes more than 10-15 min. The brush may have to be cleaned with NC thinner in between.
  2. I usually collect the NC thinner and varnish that is wasted in a bottle rather than dumping it in the sink. 
  3. Make sure to clean the brush with NC thinner and the bowl you use for mixing. Wipe both clean after you use them. 
  4. You cannot get the varnish off with water or soap. Either use gloves or wipe your hands with NC thinner to get the stickiness off. 
  5. Keep some cotton waste cloth for this. Most of my old t-shirts end up as paint cloths. 
  6. The hardener and the PU varnish has to be air tight. I they are not, they will harden. 
  7. Although the tin says use the entire contents in one go, in reality for small projects I would need only a few tea spoons full of varnish. I use a small teaspoon to measure out varnish for small projects and a large 'sambar spoon' to measure out varnish for larger projects. If one is careful, you can use this tin many times until it is finished. 
  8. Keep sufficient NC thinner ready in case you knock over the varnish tin. Keep sufficient cloth ready if you knock over the NC thinner too. 
  9. Wear your old clothes. Staying away from curtains will prevent splashes of varnish on them and will promote marital harmony. 
Matte or Glossy?

I prefer matte. This retains the natural look of the wood, and after two or more coats, the wood actually looks as though it has not been finished at all. 
I do not like glossy. It finally gives a 'plasticky' feel to the finish. However many do not share my views and like a glossy finish. 

To stain or not to stain?

I do not like staining wood. It hides the nuances of the grain. However if it needs to be done, I apply either Asian paints stain or Sheenlac stains on the wood directly before I apply the sealant. Keep in mind that both the stain and the sealant are soluble in thinner. So as you apply the sealant, the stain may also change. Drip marks of the sealant  may contain the stain and may spoil the appearance. Once the sealant and the stain are dry, usuall applying varnish over this is not a problem. 
A scratch on stained wood, will be more apparent, as it will appear as an area without stain. In contrast a scratched on unstained wood, will not be so visible. 
Scratches on stained wood will need more care when varnishing. You may have to apply stain again. However scratches on unstained wood can be easily varnished over. 

Happy finishing!

Thursday, March 16, 2017

Rotary tool bits

This is a small set of bits for rotary tools. I bought the bits from eBay. The wood is a small branch that was lying around. It was cut and shaped by Sven -Erik.

Tuesday, March 14, 2017

Kids workshop at the Club

It was great to have Charlotte and Sven-Erik with us the last month. One of the things that we did was a children's workshop. I have not used hand tools a lot.
Getting the club ready for the workshop involved cleaning it up and getting it into some kind of order. Sven did a lot of the cleaning... We got rid of four mice, one rat, two bats, and I had displaced three squirrels from the club. We managed to get them out without any harm on both sides.
We made numerous trips to shop for hand tools. We visited HMS tools and Kwality Plywood in Vellore many times, and had great shopping trips. We stocked up on hand tools such as mini hacksaws, hammers, files and hand drills.
Below are some of the photos of the first workshop with Sven, where we made name boards. We used finger jointed rubber for the base and some plywood beading (supposedly sourced from China) for the letters.
There was a lot of prep work that was needed to be done to get the boards and the strips ready for the letters. It was fun and a learning experience.

Planning out the layout of the name board

cutting out the beading strips using a small jig that Sven made. The work tables came in handy. 

The mini hacksaws were really useful

Fixing the letters with fevicol

Saturday, March 11, 2017

A woodworking club in Javadhi hills

Sven and I were privileged to be involved with setting up a woodworking club in Koviloor, Javadhi hills. This was possible due to the efforts of Dr. Anu Rose and the CHAD team as well as the Don Bosco group who have been working with the children in Koviloor. We started  out on a Saturday morning. There were about twenty enthusiastic children there from the ages nine to fourteen. We made two sets of the alphabet as well as the club sign. We returned in the afternoon after lunch. All of us (Sven, Charlotte, Basalel and I) had a wonderful time. We hope this initiative will carry on. We hope to train volunteers from Jawadhi in the club so that they can carry on teaching the kids there.

The children made a large sign for the club. Made with plywood beading and finger jointed rubber. Finished with liquid paraffin

Translating for Sven at the beginning of the workshop

A sample of the letters we made

Saturday, March 4, 2017

The rat race!

We had stored a lot of wood in a room in the club. As it was not touched for some months, there were rats, lot of them. More specifically mice.
Sven and I got rid of most of them. We laid out a maze to guide them to the door. It worked... well kind of....


In memory of the rodents we so unceremoniously displaced, Sven made this...

Friday, January 27, 2017

Wooden plaque

This is a wooden plaque made from teak wood. The lettering is finger jointed rubber. Finished with Asian paints PU matte for the base and aquadur PU matte for the lettering. I used stainless steel nails to nail the letters in to make sure the plaque lasts.


Saturday, December 31, 2016

Hardware and Mill Stores, Vellore

I would like to document a very interesting experience that had a long time ago.

This was somewhere in the year 1999 or 2000. I was a second year medical student. For many of the activities that required acting or music, I usually found myself in the group that made props. We had precious few tools in those days. Power tools were  a luxury. Power tools in the hands of students had not even crossed our minds. We used to use hacksaw blades (without the handle), when they broke, we used the broken blades to save us the trip back to the hardware store seven kilometers away.

It is in this scenario that we decided to borrow a drill from the faculty, and none less than the Principal of our college. I think it was a Black and Decker drill. I remember being drawn to the name... "Black and Decker". Sounded so good when it was vocalized... He readily gave it to us, intact in its original packaging.

I tried to look after it and treat it like a treasured possession. However despite my best efforts it picked up a few scratches, and a blotch of black paint on it. And when I did decide to return it, I found out to my horror that I had lost both the drill key, and the original packaging. I hunted around in the mess we had made in LCR, turned over every bit of cardboard, rummaged among all the waste, but the key and the box were gone.

I had no idea what to do next. I however decided to make a trip down Gandhi road to Long Bazaar, and finally landed as a skinny nineteen year old, at the entrance of Hardware and Mills Stores (HMS) Vellore.  I cannot remember what I said to the gentleman over there, but I remember him sending up one of his workers into his upstairs stores. I remember him tossing down an empty black and decker carboard box. I remember the feeling of sheer incredulity that I felt, realizing what he was doing for me. I remember him promising to order a drill key (which I picked up from him two weeks later). The principal got back his drill complete with Black and Decker packaging and key.

Even now, when I think of the extent to which he went to help a clueless lad, I am amazed. Seventeen years and more than seventeen kilos later, I still visit HMS stores. I have bought several power tools from him. He is now a dealer for many other companies such as BOSCH and Ferm. What keeps me going is not only the present, but it is also the memory of what happened seventeen years ago, when he went out of his way to give me an empty cardboard box.



Keeping a cupboard closed

Keeping a cupboard closed
I noticed this ingenious way of keeping a cupboard closed. This was at the office of the Bangalore Medical College.