A chalk box and line is used to establish working lines. The chalk box is a teardrop shaped metal container with a reel which automatically coats the string with colored chalk as the string is rewound. The reel will hold up to 100 feet of string. As the line is reeled out, it can be stretched taut and snapping it at the center will produce a straight chalk line. The chalk is available in a variety of colors which will allow its use for marking work lines for the carpenter and also for other trades.
On job processes where a chalk line is not required, a working line can be established by using string that is stretched between two given points to establish working dimensions.
A chalk line, held taut and
snapped onto a surface, will mark a perfectly straight line — up to a point. But
beyond 16 feet or so, it’s difficult to get the string tight enough to snap a
crisp, accurate line.
The trick to marking long layout lines is to double-snap the string. Here’s how: Stretch the string tight and tie it off. Then move to the midpoint of the string and hold it down with your thumb. Now snap one side to mark half of the line. Repeat on the other side to complete the line. Be careful the string doesn’t move as you reach over to snap the second half.
If you’ve got someone to help, you don’t need to tie off the string. Just pull it taut and have the other person double-snap it from the middle.
Source: www.thisoldhouse.com
Tip: Chalk that Won't Stain
While working on the interior of your house, anything that can eliminate as much
of a mess as possible is always a plus. So, when using a chalk line to mark
surfaces- such as walls and flooring- use a white color. Red and blue will
permanently stain.
Source: www.handymanmatters.com
Chalk alternative in snap line
I once was on a job and had my new snap line, but no chalk to fill it with! I went to the quick mart on the corner. All I could find was baby powder, and WOW! I filled the reservoir with baby powder, gridded off the area, and when I was done, one blow, and it was gone.
And I felt fresh and dry all day!! Seriously, it works.
Source: www.signindustry.com
When
two carpenters team up to snap a series of lines with one chalk box, such as for
laying out siding or shingles, one or both workers have to walk over to their
partner every time the line is retrieved for rechalking. Here's a simple
step-saving technique using two chalk boxes: First, hook the two chalk lines
together by inserting one clip through the other. If the holes in the clips are
too small or the clips tend to unhook easily, simply tie the clips together
instead as shown here. Next extend the line from just one of the chalk boxes and
snap your layout until the line goes dry. Then crank in the dry line to pull the
opposing line out of its box for more snapping. You can rechalk this way as many
times as necessary with no walking required.”
—Daniel Verhaeghe,
member of Carpenter Local 706
in Saginaw, Mich.
Source: www.carpenters.org
Snapping angles on OSB
Snapping
a line across a sheet of OSB at an angle greater than 30 degrees can be rough by
yourself. H-clips are used to reinforce OSB sheets between trusses. Loop your
chalk line around one of the tabs of the H-clip and slip it on the other side of
the sheet where your mark is to prevent it from slipping when you snap your
line. There are different thicknesses of these H-clips, but if you're putting a
roof on they should be handy for the thickness you're using. A spring-clamp will
also work. If you don't have either of those handy and the OSB is thick enough,
just toenail a nail in the corner of the OSB and hook your chalk line on that.