Vaughan 6th January 2005, 06:54 PM Hi
As you can see by the the stupid question, I'm am newbie to woodworking. When I buy a piece of wood ie: 2m in length. I would like to know if the one side is straight. A short piece is fine, use a steel ruler, but when it is so long, how do I make sure it is straight.
Thanks for your time.
Cheers
Vaughan
Gumby 6th January 2005, 07:14 PM Hi Vaughan. First of all, there's no such thing as a stupid question in here. We were all newbies once and I've picked up virtually everything I know in the past 18 months form people in here and at the woodworking club (you should join one by the way) by asking questions.
The answer is that its virtually imposssible to buy a straight piece of wood off the shelf. You need to get it run through a jointer on one side and then a thicknesser on the other to get it absolutely square. Then you can do much better with your woodworking. That's why I started off with just my Triton and now have a garage full of machinery including a combo jointer/thicknesser. You can get it done at some of the smaller furniture type factories if you had one large project to do. Otherwise, dig deep and enjoy the ride. After all, you cabn always sell the machines again later (ir at least, that's what i tell the misses!) :rolleyes:
bsrlee 6th January 2005, 09:56 PM What Gumby said, twice :-)
What you have to look for is timber that REALLY out of shape - corkscrewed, cupped (more like 'spooned'), big knots missing....Just put one end of the length in front of your eye, sight down it, turn over & repeat. If it doesn't look the same both ways, there is probably something wrong. Long, thin pieces will sag a bit, so hold the timber thin edge up to minimise this - it will still be saggy, but it should be the same when you turn it over.
If the timber is bent like a corkscrew, or it has a number of small surface cracks, or big bits missing out of the edge, splits etc, just politely reject it, put it back on the rack & look for another piece. If some sales-thing tries to make you take the dud bits, politely say 'NO". If he keeps it up, just walk out the door & don't go back - I have had it tried on me & found there are better yards down the road.
silentC 7th January 2005, 08:42 AM Just to embellish that a little bit: if you hold the edge of the timber up and sight across the corner nearest your eye and line that corner up with the far corner, you can see if the timber is bowed because it will either dip away in the middle or obscure the far corner all together.
Hold the board on the flat, sight along it and try to line up the near edge with the far edge. If they don't line up, the timber is warped.
zitan 7th January 2005, 01:14 PM For checking straightness on a real long piece an easy way is to use a bit of string and a mate or some tape to hold it there. Won't detect warping or twist though.
aussiecolector 7th January 2005, 01:27 PM It depends a bit on how straight you nead it and how much you are paying for it. If it is rough sawn for framing etc you have to expect to get some lengths not quite right,but you would want most to be pritty good. You shouldn't have to pay for any thing which is badly twisted or bent though.
On the other hand if you are paying top doller for dressed furniture grade timber you can expect it to be good timber.
mikev 7th January 2005, 10:28 PM For a shorter piece say a tee square blade or straight edge for the workshop. Lay it on the flat, draw a line then turn it over and the reverse side should show if it straight or not. That is it will show if it is high or low of the original line and where you need to plane.
silentC 7th January 2005, 11:11 PM I was reading something somewhere the other day and the author was pointing out the importance of learning to trust your eye. One of the first things I learnt when I started work in a joinery was how to sight a piece of timber. It's a very useful skill, not hard to learn, and will serve you well when you don't have any paraphernalia with you.
outback 8th January 2005, 03:44 PM I've been tryin' that, fer some reason it just don't seem to work.
ribot 8th January 2005, 04:59 PM Use your eye, you will be surprised how well it works just don't doubt your first impression. If you think it's bowed the first look down it's length, it will be. Put it down and go for another piece.
Gumby 9th January 2005, 06:00 AM If some sales-thing tries to make you take the dud bits, politely say 'NO". If he keeps it up, just walk out the door & don't go back - I have had it tried on me & found there are better yards down the road.
How do you know if you aren't already at the better yard down the road ???
jacko 9th January 2005, 09:01 AM I was reading something somewhere the other day and the author was pointing out the importance of learning to trust your eye. One of the first things I learnt when I started work in a joinery was how to sight a piece of timber. It's a very useful skill, not hard to learn, and will serve you well when you don't have any paraphernalia with you.
Well and good unless you happen to wear glasses. Distortions in "straight" that are a fundamental "feature" of optical enhancements can be very disturbing.
Jacko
barnsey 9th January 2005, 10:54 AM When I go shopping for timber I take the tape measure, a 6" or 12" rule and if I'm looking for boards wider than that, a pair of winding sticks. ;)
They are just sticks that will stand on their edge, straight parallel sides and exactly the same width and length as each other. Place them on the board and you can check for bow, cup & warp. :)
Check all the sides with your eye for straightness and use the rule and/or winding sticks as tools to check the other features again by eye. :p
Mind you if you're like my old man who's sight is shot - think you have problems :eek:
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