gwilson
Diamond
- Joined
- Oct 1, 2006
- Location
- williamsburg va
When I posted pictures of the brass indexing attachment I made for my rotary table,I mentioned that I spaced the holes with simple dividers,and drilled the holes with a pump drill. Some asked what is a pump drill.
They are a very old type of drill used mostly in clock making and silver smithing. They are only good for smallish holes,about 1/16" is the largest diameter that is practical. But,you can drill holes very exactly where you want them if you know how to use these simple drills.
The brass wheels are about 2 1/2" dia.. I am re posting the brass index for those who may not know what I referred to. After drilling the holes with the pump drill,I re drilled the holes with a small center drill to bevel the edges.
I made many bits for these type drills. Just made from drill rod and hammered flat,with 2 cutting edges filed on the ends of the drills. 1/8" shanks. The chucks hold only 1 size shank.
This is a batch I made,but I must have made a dozen others for craftsmen in Williamsburg to use.
This particular batch,I took with me when I went to the flea markets in Pennsylvania. I left them sticking up out of my back pack,no sign on them at all. Sold every one of them for enough to buy other stuff,and pay for the trip!
These are enjoyable to make because I can make all kinds of little decorative moldings on their drill rod shafts. The wheel for tightening the drills is knurled. Bad picture. It was 1" in dia.,and gave enough leverage to tighten the bits well. The split chuck has a tapered thread. I made the threads by backing up the cross slide as I cut them. They didn't have to be especially precision,but after you've done it a few times,nice tapered threads can be made.
Don't make the brass fly wheels too heavy. If you do,the drill runs slowly due to the inertia it takes to get them going.
They are a very old type of drill used mostly in clock making and silver smithing. They are only good for smallish holes,about 1/16" is the largest diameter that is practical. But,you can drill holes very exactly where you want them if you know how to use these simple drills.
The brass wheels are about 2 1/2" dia.. I am re posting the brass index for those who may not know what I referred to. After drilling the holes with the pump drill,I re drilled the holes with a small center drill to bevel the edges.
I made many bits for these type drills. Just made from drill rod and hammered flat,with 2 cutting edges filed on the ends of the drills. 1/8" shanks. The chucks hold only 1 size shank.
This is a batch I made,but I must have made a dozen others for craftsmen in Williamsburg to use.
This particular batch,I took with me when I went to the flea markets in Pennsylvania. I left them sticking up out of my back pack,no sign on them at all. Sold every one of them for enough to buy other stuff,and pay for the trip!
These are enjoyable to make because I can make all kinds of little decorative moldings on their drill rod shafts. The wheel for tightening the drills is knurled. Bad picture. It was 1" in dia.,and gave enough leverage to tighten the bits well. The split chuck has a tapered thread. I made the threads by backing up the cross slide as I cut them. They didn't have to be especially precision,but after you've done it a few times,nice tapered threads can be made.
Don't make the brass fly wheels too heavy. If you do,the drill runs slowly due to the inertia it takes to get them going.