One of the things that fine woodworkers commonly do to get better accuracy in their craft is to get rid of their pencils.  Pencils get dull, are difficult to see on many woods, and the thickness of the line varies with the level of sharpness and angle of use.  All in all, they're just not an accurate way to mark out detailed work.

That's why instead they use a "marking knife".  Basically a knife with a very sharp point that is only sharpened on one side.  (That way the back is flat to ride against the ruler, square, or whatnot.)

The problem is that these knives generally cost between $10 and $50, and a good toolbox would be stocked with 2-3 of them.  (Left, right, and ambidextrous)That certainly adds up! (Here's an example from a popular catalog for comparison.)

The solution I came up with is not only made 100% free using stuff you'd normally throw in the trash, but the blades are replaceable, the handle is nice and big for people with arthritis, AND the whole thing can safely go with you in your pocket!

So what's the big secret, then?  Re-engineer your spent utility knife blades!!!


Before we go on, I just wanted to insert this little bit of legal keister-covering.

This project involves potentially rusty razor sharp objects, modifying tools beyond their intended purpose, hazardous chemicals, flying sparks, and possibly feeding a Mogwai after midnight.  If you do not feel qualified or safe doing any of the above, please surf away from this page (and probably this entire site) and take up a more relaxed hobby like perhaps macrome or counting the number of leaves on your front porch.

If, however, you're willing to take responsibility for your own foolishness in copycatting frightening stuff you find on the internet, then you have come to the right place.  Welcome aboard, my friend!
this is cool, I recently got one of the new folding style knifes, so the old slider is basically out to pasture:). so this will be ace, its extra good because the slider was my dads, I remember it since I was a kid so it cool to give it new life.
'Tis a fine thing you have done for your country. Thanks!!!
This is an awesome idea and will come in hand for my shed building projects - howtobuildashedi.org/ Nice woodworking knife indeed.
If you have a decent sized magnifying glass - you can often take a photo 'through' it. I've even used a standard digital camera to take photos through a microscope and telescopic site. <br>You might not get only the point of interest in the shot, but it'll be framed by the magnifying glass so it's all good.
Also, to make sure the edge is in focus, be sure to have it pressed against something. By focusing on the background, the very edge will be in best focus, instead of some spot on the flat of the blade, or way beyond the blade.
I'm not a woodworker but this is a neat idea. I can fully commiserate with you on getting a good picture of a sharp edge without a macro setting on the camera, even WITH a macro setting its difficult!

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