Splitting the line.

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homeinthecity

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I was wondering if anyone had views on ‘splitting the line’ when sawing. I’m trying to improve my sawing accuracy after seeing joints coming in a saw kerfs width narrow.

My assumption is that I should start sawing so the kerf lines up to the waste side of the line, not directly down the middle of it…?

(I’m amateur and self taught, so apologies if this is a very basic question!).
 
I was wondering if anyone had views on ‘splitting the line’ when sawing. I’m trying to improve my sawing accuracy after seeing joints coming in a saw kerfs width narrow.

My assumption is that I should start sawing so the kerf lines up to the waste side of the line, not directly down the middle of it…?

(I’m amateur and self taught, so apologies if this is a very basic question!).
Yes thats it. But if it's e.g. a thick pencil line, in theory the cut is down the middle and half of it is left on the workpiece. If it's a very thin line e.g. a knife cut, then the kerf goes to the waste side, as you can't split a knife line.
 
Leave the line
Take the line
Split the line

Three terms to help you increase accuracy when working with a pencil or ink line.
It does work.
You might leave or take the line depending on how you marked out in the first place, left or right handed side of a square for example. I use one or the other of those much more often than splitting the line, and the cut is made with a mitre or handheld circ saw more often than with a handsaw.


For precise work like furniture and cabinets, mark with a knife is best and put the kerf in the waste as recommended.
If you use japanese style blades with alternating ground teeth, you can place the tips of the teeth either left or right side of the blade in a knife cut and follow it.
Using a western style saw with a "set" where I definitely lack skill, I have also found it useful to make two knife cuts a little wider than the kerf, cut between and then finish down to the line by chisel or plane. I'm sure you grow out of that with practice but the brain seems to be good at putting a cut pretty well in the middle when given two edges.
 
Imagine a pencil that leaves a one inch mark on the wood.
You measure, draw the line. Which is accurate?
left side of pencil mark
Right side of pencil mark
centre of pencil mark?
Whichever, is down to you. If you use a marking knife, the one inch reduces to <1mm.
Same logic applies. Where did you press down opposite the ruler mark?
You want the wood to finish up measuring to that length, maybe after clean up.
 
Yes thats it. But if it's e.g. a thick pencil line, in theory the cut is down the middle and half of it is left on the workpiece. If it's a very thin line e.g. a knife cut, then the kerf goes to the waste side, as you can't split a knife line.
Forgot to say - in general a marking knife is best avoided and if used at all only for those few cuts which will be visible.
They are misnamed and aren't for marking at all - they are for cutting the start of a line where a perfect edge is needed. They are useless for general marking as they are indelible and everybody makes mistakes. Making a precise line doesn't necessarily mean it's in precisely the right place.
I wouldn't touch them at all (if ever) until fairly confident with pencil only.
There you go - lots of contradictory advice and the thread has only just got going! :LOL:
 
Imagine a pencil that leaves a one inch mark on the wood.
You measure, draw the line. Which is accurate?
left side of pencil mark
Right side of pencil mark
centre of pencil mark?
.......
Has to be centre of the mark for consistency. If not you will simply get it wrong quite often, unless you add another mark to indicate which side. But then you might get that one wrong too.
Keep it simple!
 
If you put the ruler in the right place the edge of the pencil line facing the ruler is in the right place- if the middle of the line was to be in the right place you’d have to somehow mark underneath the ruler…
Pencils don't have edges.
Newly sharpened will be a point. As you use it you have to twist slightly so the point gets worn into a rounded cone, still central. This means that to get the centre of the lead to join two marks, the ruler will have to be offset slightly. It's just normal pencil use.
I guess the technique of twisting the pencil as you draw might have escaped some beginners but once you have it it becomes natural.
Come to think - of you don't have the twisting technique I see that pencil use could be problematic - is that what all the difficulties are about?
PS I dimly recall many years ago be told how to spin the pencil as you go along a straight edge. Maybe I wouldn't have picked it up otherwise!
 
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I just googled it. Did you know: "Notching the middle of the lead with the corner of a file makes it possible to draw two parallel lines at once, a technique used by artists and calligraphers."?
Something new everyday!
 
Whatever convention you adopt, stick to it.
It's rare in woodwork to need a dimension to be precise, but it's common for a number items to be precisely the same (or as near as dammit)
Brian
 
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