I am not certain something like this exists but I hope so. I need a pen or marker that will draw a line as small as a pencil and up to a 1/4 wide or more depending on the pressure applied to it. Standard markers do this somewhat but are not near sharp enough.
Most markers with a fine tip are either limited to that width, or, if squishable to a wider mark, won’t tolerate being squished that way for long - they will get wider and wider with light pressure until the tip is basically El Marko Magnum 44 territory.
Calligraphy markers and other chisel-point markers can do the job by rotating the tip from the knife edge to the wide edge… but it will take some practice and skill to make smooth transitions, and the tips tend to lose their precision quickly. (They’re for very delicate work and will last under that usage, but not for anything more… robust.)
Good suggestions. I may be able to adapt a caligraphy type marker.
what I am doing is trying to modify my bend gage. A 4" long block of wood with a pencil whole going down the center. I adjust the pencil so it will mark the high spots if I run it acrosss a bent board. With a pressure sensitive marker I would have an ability to map the curve visually based on the width of the mark left behind, we don’t use a simple radius the rate of bend changes along the length and is now just done by eye.
Try the Crayola SuperTips markers.
James, I will take a closer look at them but it looks like it has to be rotated to get the wider mark.
I Googled “paint brush markers” and turned up a few interesting things.
How about a Brush pen?
If be concerned about the ink soaking in and distorting the line width on at least some woods. Good idea, may be a bitch to implement successfully.
Yep, the ink does distort as it flows, also paint or inks will dry out on the tip when left exposed. I might have to figure out how to arrange a bundle of pencil lead with a cone shaped spring sitting on top of the stack.
I think I found a solution. I can buy small tubes with an id that will match pencil lead, I can also buy small springs with the same od as pencil lead. I will just stuff the tubes with the springs and lead then sharpen the entire bundle to agree with the range of variance I am looking for.