I'm familiar with pump drills, but never seen one as a drill press. Anyone know anything about these?
https://www.youtube.com/watch?v=9D__A2gK2_o
I can't tell from this video how he got it to press/up/down.
Have you got one?
Ever seen one? Video/article?
Care to speculate if you haven't?
I have got to have one.
Ya as I said, I'm familiar with pump drills. I've made a couple my self. I know how the spin is achieved.
I was convinced there was some part of that press that was doing the lifting. I posted elsewhere and watched it again several times slowing it down. I'm now convinced he's just pinching it between fingers to lift before moving to next hole.
I thought I had found the next great thing for my 'shop'.
While searching I did find a jewelers pump drill that had a base that was spring loaded to push the work up. Interesting, but not what I'd want.
I am going to attempt to make one that does have a mechanism for raising/lowering.
There are various bits. One type, easy to make, is shaped lie a flat head screw driver with the head angled down from the mid point. Also, apparently, that is one of the most efficient cutting shapes.
You can also take a nail, which if you look at it has four flat sides on the point, just take a file to each side to sharpen the edges a bit and give more surface if possible. Actually I guess that is the easier to make.
Spoon bits might work too, but they are costly and I don't think they come in very small sizes.
I learned to make these things for starting fires. I never knew they were used as woodworking implements.
The disk on the spindle (vertical shaft) has significant weight to it. The spindle is notched or drilled though near the top, where the midpoint of the cord is set, and attaches to the bow (horizontal plank) on either side.
The cord is then wound around the shaft manually. Once wound, pushing down on the bow causes the spindle to rotate. Due to the weight of the disk, the shaft keeps its momentum, and rewinds the cord around the shaft. The next push on the bow has the same effect as the first, but it the opposite rotational direction.
I expect that this type of drill would need a bit that is designed to cut in both directions of rotation. Very cool, thanks for sharing.