Planing Wood


Teak Board

The Monsoons in North India have thus far been rather unsatisfactory although they seem to have picked up somewhat in the last one week. The weather has remained extremely humid despite the lack of rain and there is damp everywhere, more so in my little workshop which has remained incredibly stuffy and uncomfortable. I have only been able to work in short stretches in there and that too intermittently due to other preoccupations. All I have been able to do since my last post several weeks ago is to prepare six teak planks, each roughly four and a half feet in length. I first ripped the raw planks to five inch wide strips, then glued two together to form ten inch wide planks. The pieces seem to have stabilized and I have tried my best to flatten them with my 18 inch long jointer plane. After flattening them the best I could, I used my smaller smoothing jack plane to further level out the surfaces. 
 
This has proved to be hard work because the planers in the timber market where I sized the wood had left a lot of knife marks on the surface of the wood. I have discovered that there is no way to ensure that the cutters and planers at the lumber yards do not leave any marks at all. I doubt whether the blades of their massive planer-thicknessers are sharpened very often. Each of these machines go through prodigious amounts of hard wood each day and it is unlikely that their blades remain sharp for very long.
The other problem with the glued up planks was the slight but noticeable undulations particularly along the glue lines as the original pieces had not been jointed after being sawn and hence did not align perfectly. I managed to get the planks pretty flat but not perfectly flat. I aspire to perfection but rarely achieve it!

My hand planes - the bigger one is the jointer
The other time consuming issue was tuning my hand planes. In India planes are very cheap (cost between Rs 400 and 800 compared to the world famous Rs 15,000 planes made by the Canadian company Veritas) but most need considerable tuning to work well. To begin with, the soles of the planes are rarely perfectly flat as they need to be to function well. To flatten them I glued two long strips of sandpaper (one 80 grit and the other 120) to a pieces of glass and then painstakingly ground the bottoms of the planes. This procedure took several hours and buckets of perspiration even though I worked outdoors. 

Then I took apart the planes and adjusted the shoes on which the blades sit and so on. Then came the business of grinding and sharpening the blades. Much has been written about this process and various methods are recommended by different woodworkers. One person who has been very influential in recommending the sharpening and use of hand planes is the celebrated English woodworker David Charlesworth and his methods are worth looking up on the Internet. Blade sharpening can be a long and tedious process especially if it the blade is new. The blades come from the factory with clear grind marks and a rough bevel. Much needs to be done before they can produce clean shavings.

Sharpening consists of producing a fine angled edge – usually between 30 and 25 degrees. This requires the long side of the iron to be ground to a fine degree of flatness. The entire length of the iron need not be flattened as only the last inch or so is relevant. Once this side has been flattened and has acquired a polish, the bevel on the other side needs to be similarly ground and polished so that the intersection of the bevel and the flattened back forms a keen edge.

Charlesworth recommends the creation of a fine secondary bevel at the very tip of the flat side. This is achieved by placing a a thin strip of metal such as a hacksaw blade on one edge of an abrasive stone of high grit (perhaps 1,000 or so) and further grinding the flat edge of the iron. Very little grinding is required to produce this secondary bevel but it seems to work like a charm. While Charlesworth and other master craftsmen prefer to use expensive Japanese water stones for sharpening, I get by with sandpaper and a few cheap diamond stones I had acquired some years ago. I find the results with these cheaper alternatives to be more than effective for my needs. I must confess however that I have no idea what it feels to use one of those expensive Canadian or US hand planes.

Once re-assembled, my cheap, mostly Jalandhar made, planes can produce extremely fine, ribbon-like shavings. Once tuned, the ordinary hand plane becomes something of a precision tool that is a delight to work with. Although the smoothing achieved by a plane can be superb, I still need to have a go with the belt sander and then with a random orbital sander. This is because of the chip outs and serrations caused by the knife blades at the lumber yard.

Fine Shavings from my Jalandhar made hand plane
 The preparation of wood, especially hard woods like Teak and Sheesham, is complicated by their inherent imperfections. Knots and complex grain patterns can cause many problems. I find that the less than perfectly sharp blades of a thicknesser can cause random chip out in the areas where the grain pattern changes or the wood hardens. Planing works well when the grain direction is uniform in one direction. In such wood, like Mahogany, planes rarely tear our pieces of wood or produce unseemly gouges. The problem occurs when the grain direction changes dramatically as in the case of knots and swirls. The hardness of the wood also varies in these spots. Machine planers, especially if their knives are not perfectly sharp, tend to gouge out little pieces of wood leading to much imperfections on the wood surface. 

Knots and Swirl Patterns
Rectifying such imperfections is almost impossible with a hand plane not only because the dents can be deep (as much as an 1/8th of an inch) but also because the hand plane too tends to create gouges when it hits the cross grains of the knots. These parts can only be planed with a smaller plane worked along the grain pattern.  

Wood dust and cyanoacrylate glue
Deeper gouges, dents, depressions and loose knots have to be filled and fixed. There are various methods of doing this; I prefer to use wood dust (generated by my random orbital sander) and cyanoacrylate adhesive. The wood dust should be packed into the dents, holes and so on and then covered by a few drops of CA glue. The glue hardens in about an hour and the glue-saw dust patch can be sanded down pretty well. Be aware that the wood treated with CA glue tends to darken significantly but stain and a good finish is all that is required to disguise it completely.

Knots in the wood have been plugged but serrations remain
Before staining, however, the wood requires another round of sanding, mainly with a random orbital or finishing sander, using grits through 240 to 320, for a more acceptable surface. By this time most defects should hopefully have been smoothed out and the wood surface have acquired a uniform sheen.

Indranil Banerjie
26 August 2012

Comments

  1. Do you do any machine planing with the small electric planers or do you directly do hand planing after the machine planing in the lumber yard?

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  2. I go directly to hand planing because I cannot seem to get adequate control of the power planer, which I use more on rough wood. The hand plane is a fine precision tool which can remove extremely fine shavings. Power planer can never match it.

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  3. I have yet to get started on hand planing. In US we get two brands of Planes from India. Groz and Anant. I purchased Anant but was disappointed with the quality. Especially the blade that came with the plane was bad. Putting a good quality blade costing $75 in a $40 plane has held me back so far.

    In the woodworking class though I have used a well tuned hand plane and came out with thin and soft long curly shavings. I think the brand there was Record. Woodriver planes which have come out over the last couple of years seem to be almost as good as Lee Valley and have been received well. Stanley has also restarted the production of quality hand planes and they are also considered quite acceptable with minor tuning.

    When I started acquiring tools for woodworking about 6 years back I was inclined to start off with hand tools but the prices shocked me. Often they were as costly as a pretty good quality machine tool. So I made a choice to start off with machine tools.

    I have been contemplating getting a decent set of hand tools for the last one year. I aquired a Spokeshave 2 months back. It took me weeks to even get comfortable in adusting the blade.

    That said the most important tool in western style woodworking is a good workbench. It was almost a year and half till I made my work bench and I just put a vise in it last month five years after I made the workbench. Now I need to make some more improvements to be able utilize the full capabilities.

    Eastern style of woodworking be it in Morocco , India, China or Japan works a different way I doubt if someone like me can easily adapt to it. Even then there is a problem of find enough resources to learn it.

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  4. If I had a power jointer and a sharp thicknesser, I probably would not have bothered too much with a hand plane. But not having either, the good old hand plane is the only solution. I have a workbench of sorts but have not been able to fix a wood vise and nobody seems to sell a tail vise, bench dogs and so on here in India. I have to fall back on primitive but effective methods for clamping, including wedges which work surprisingly well!

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  5. Sir, i have been going thro your blog for quite some time, particularly during my 6 months stay in USA with my sons. I am a avid woodworking DIY enthusiast. I have made a workbench before i left for USA. I have posted some pics and brief write up on the workbench, on diyable.net and the link to my post is

    http://www.diyable.net/forum/viewtopic.php?f=18&t=300

    My workbench is yet to get the Bench Dog holes to the Face Vice and once I am able to fix a good Tail Vice, Bench Dog holes for it. Though, Bench Dogs are unheard of in the entire Bangalore Market, i Located Top quality SS Dowels of 3 inches long and 18 mm dia and I am going to grind a flat face on one end of each dowel and fix two dowels with flat faces in same direction and fix the work piece between them. One dowel would come into the Teak blocks, which is ready to be fixed inside the jaws of the vice, flush with the metal edge and table top. This wooden blocks would apply even pressure and prevent any damage to the wood pieces held between the jaws.

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  6. To Divya-Desam: Congratulations on making a superb bench! I haven't got as good a bench as your's and your idea of making bench dogs is great. Apart from grinding one face of the steel dowel flat you will also have to cut a notch at the bottom of the dowel to make it flex slightly. Best wishes and looking forward to getting more ideas from you. By the way, where did you get your tail vise? because I have been unable to get one here in India.

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  7. That's a very informative article indeed. What is the brand of cyanoacrylate adhesive that you used? What brands are available in India?

    I am looking for a remedy to fill gaps and cracks. I didn't like putty which I used in my previous projects. Wood dust with cyanoacrylate adhesive seems perfect solution.

    Thanks,
    Bhairav

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    Replies
    1. Bhairav: There are plenty of companies producing cyanoacrylate glues including Pidilite. I got some from a company based in the NCR. Fill the gap with wood dust and then put a few drops of ca glue - should do the job. You might have to fill it a second time.

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