Words: Jude Nosek, Keson/SOLA
Humans love straight lines. Our streets, sidewalks, sports fields, and foul lines, railroad tracks, walls, decks, foundations, shelves, roofing tiles, hopscotch layouts- straight lines are found everywhere we build. However, we humans are terrible at drawing straight lines unaided. Try it! I would be very impressed if you made it past five inches and were confident and happy with the result. To make it even three feet from point A unaided, drawing a straight line, freehand will take some time. That’s why we have built so many machines to make things straight and to make straight lines for us. Up there with the best of these tools is the chalk line.
At its simplest, a chalk line is: A string, coated with colored dirt, is pulled taut between two points A and B. The string is drawn up off the surface to be marked, like a bowstring without the arrow, and released. When the string snaps back to the surface, some of the dirt falls off marking a line from A to B.
We are going to cover the three basic components of the chalk line marking system:
- Chalk (the colored dirt that indicates the straight line)
- Chalk Line (the string, or cord, that picks up and lays down the chalk)
- Chalk Line Reels (the tool which brings those two elements together)
Chalk line, aka “the string”
Since about 2000, string has become the biggest story in the chalk line reels. When shopping for a chalk line, be mindful of the marketing. What is defined as “thin”, “precision” or “fine” string for one will NOT be the same for another. There is a LOT of proprietary wording when it comes to chalk line reels. Each manufacturer has its own system, marketing story, and materials. So, what is “Ultra Bold” line for one manufacturer, is “standard” line for another, etc.
Why so many options? It depends on the work being done and the worker. A precision line will look more like a pencil line, a giant line will look like a magic marker line. The former is great for flooring where precision is paramount, the latter for cutting concrete where visibility and duration of the line are key. Here is our chart for string types. Standard is by far the best seller (70% of the lines sold are standard lines).
What are the most important criteria for you?
- See the line? From how far away, for how long a time?
- Snap multiple lines?
- Easy clean up?
Tip: It is too much trouble to remove chalk from a chalk line reel to introduce a second color to a job site. If a second color is required (to correct an errant snapped line for instance), have a second chalk line reel for the second color.
We once asked a carpenter about which color chalk he used. He said, “Red.” We asked why. He shrugged and said, “That’s what my first boss told me to use.” As far as we have been able to ascertain from market surveys, there is not standard usage for the color of chalk. This is true across trades, geographies, etc. There are preferred colors: Red > Blue > White > Glo Orange > Black. These are the big movers.
In inclement environments (wet, windy, high traffic) OR when the chalk line will not be seen (footers, wall layout, roofing) more permanent colors are rising in popularity. This is because a line that lasts is preferable to one that cleans up easily. All chalk lines are semi-permanent, eventually, they will all wear away. The industry has aligned around a numbering system.
- wipe away
- standard temporary use (same day),
- hi-vis color (1-3 days),
- semi-permanent, weather/wear-resistant (3-7 days),
- permanent or “weatherproof” (>7 days),
- ultimate or dye, almost pure colorant
There are a number of variables that will dictate how visible/usable a chalk line will be and how long a struck line will last.
Chalk Pigment. Level 3 and especially Levels 4 and 5 have a high dye to carrier ratio, providing a richer, longer-lasting, less impacted by the environment color. We know of some masons who spike their standard level 1-3 chalk with concrete dye. It is cheaper, more consistent, and much more efficient to simply buy more permanent chalk levels (4 & 5).
Contrast of chalk color to surface color. Blue on grey concrete stands out MUCH less after a few days than red, for example. Also, if you’re painting over the lines, make sure you choose a color that won’t bleed through.
Surface material. Colors perform differently on concrete vs. wood vs. asphalt.
User Technique. Some can coax 4-6 usable strikes out of a single chalk line before it has to be reloaded with chalk. A simple tip: raise your line two inches for the first strike and an additional inch for each strike after.
String Thickness. A thicker string like a bold or a giant carries and releases way more chalk than a piano wire-thin precision line.
Chalk line reels
This is the tool to make using chalk lines less messy (they are still messy!), more consistent, and more convenient. Reels housings typically come in two sizes: 1. standard the entire reel fits in the palm of your hand, and 2. what we call Giant, which have a grip for holding in your palm with a chalk reservoir and reel system that hang below.
About 80% of chalk line reels sold in North America are standard size, with standard string and little hook on the end. Of these, there are two primary types. 1. 1x rewind chalk line reels, which means there’s no gear, so there is very little that can go wrong with this chalk line reel. 2. 3x rewind chalk line reels employ a gear to speed the rewind, saving you 10-15 seconds of rewind time on a 50-foot line retraction. There are some 6x chalk line reels sold. An additional 3-6 seconds can be saved with a 6x rewind.
For our money, a 3x chalk line reel makes sense, 6x is unnecessary. Most chalk lines that are snapped are nowhere near the 100 feet available in a chalk line reel. Why so much string? As chalk lines wear out or break, most users simply begin the next section of the line by tying the hook to the line remaining.
Tip: To load a chalk line for the first time, pull all the lines out of the reel. Fill the chalk line reel with an ounce of chalk (about a tablespoon). Wind the string back in tapping the reel with your winding hand often. The objective is to run the string through the chalk in the reel, coating it. Add a little more chalk every 20-30 feet. Some will repeat this process.
Know that there are options out there for string types and chalk variations beyond color. We are grateful to be able to supply USA-made chalk and chalk line reels to assist in your efforts!
Visit us at www.keson.com for more information.