for Students of Woodwork
Preparing Timber Part 1 Reducing Timber to final dimensions
Timber is supplied in standard sizes in sawn and planed sizes. However, many of our projects do not conform to these sizes and these boards must be further worked.
A board may be reduced down to its final dimension by sawing along the grain with a rip saw and across the grain with a hand saw such as a cross cut saw or tenon saw. Such reduction should include an allowance for working of 5 - 6 mm per width and thickness and possibly approx. 10 - 12 mm on each end of length particularly those that a mortise is to be worked. The need of such an allowance of members with a tenon is less crucial. You should read the appropriate ‘How to do it’ sheet or favourite book to revise how to use the bench plane, vice, bench stops, marking out tools, etc.
The board or length should be fixed in the vice or held against the bench stop and planed with a Jack, (No 5 or 6, No 7 if a longer board) until the best face is flat and smooth. You will notice that there is a grain direction. The grain is rough if planed in the wrong direction Ask your trainer to show you how if you are now sure. To get rid of high spots, mark them with a soft pencil and then plane these marks off diagonally and across the grain where these high spots lie. The plane should be set fine when using this technique with the mouth narrow and the back iron close to the edge, especially when planing difficult grain. Such techniques should not be used when getting close to the finished thickness when shavings along the grain and in the right direction, should be used. Ask your trainer to show you the technique and how to set up you bench plane.
Test the board as you go by using the plane edge, rule or other straight-edge and make sure it is flat, free from twist in all planes.
We may now test the truth of the face and ensure it is flat and free from twist.
We need to have two straight edges. Some are specially made for this purpose usually out of hardwood, and are called ‘winding strips’. In practice they are set on the boards at each end and ‘sighted’. Any winding will be readily seen and if marked with a soft pencil, the high spots can then be removed until flat.
Only then do we place the symbol of the Face Mark to show that this is the flat, best face for further working and measuring from. The face mark should be drawn clearly with a HB pencil. Please don’t press too hard or use a hard pencil because eventually it needs to be removed. Biro’s or felt tip pens should never be used. Their ink bleeds and it is difficult to remove the resulting stain.
Preparation continued >
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Last uploaded 21st September 2003