Questions for you mini-mill owners

[Phil705]

I have been flailing around for many, many hours drilling and filing to get a rectangular holes through (brass/nickle silver/aluminum) for through-tang knives. I keep hearing about mini-mills and how essential they are. I do not make folders, only fixed blade stock removal jobbies. But I'm getting real tired of drilling a series of holes and connecting them with files.

So, can mini-mills cut rectangular holes in metal?
Can a mini-mill substitute for a drill press?
What accessories would you need to to typical knife work?

Thanks

Phil705
Winthrop WA

 

[sunshadow]

I make holes of all sorts with my minimill, the corners do have the radius of whatever cutter I am using, of course it is good practice to radius the outer corners of the tang anyway so I jst try to make them match somewhat

-Page

 

[godogs57]

Best piece of equipment I have bought in the last couple of years....you just have to tell yourself to go slooow with it....it's not a Bridgeport

 

[montana guy]

I do not have a mini but I do work with the full size mills. You can cut any type of hole you want with a mill and a little practice. The corners will always have a radius but if you use an 1/8" end mill it is not much to touch up with a file if you want a true square corner. One thing about square corners is that the square corner is a weak point where breaks will start, a radius is much much stronger so it is better to leave one if possible. When machining a part I always leave the radius.

Any kind of mill can be used as a drill press, it is really rare to use a drill press if you have a mill.

Basics I would recommend would be a good vise, a set of parallels, an indicator so your vise will be set square to the mill head, or if you have a movable head, the head is true to the table. (if you have a movable head and you have moved it, always indicate it in first or your cuts will be off. never trust the 0 marks on a mill and always indicate a new mill in). A set of center drills is a must. Also you will need a set of end mills and collets (if your mill has a removable chuck). Collets are kind of spendy but you will get WAY more accurate cuts with them since they are designed to do milling work. A chuck is not designed for milling work, they are long and they can flex under the pressure of a milling cut, they also put excess stress on the machines bearings because of their longer length. One of the more important things you also need to get is an edge finder so you can find the true center(or whatever point you are going for) of your work. I have one that is .200" on the small end and it is all I ever use really because it makes the math easy. To find the true center of your work once the edge finder shows it is on the true edge you have to move the distance you want plus half your edge finders diameter. So if your part is 1.000" and you want to get to the center you move the machine .500"+half the edge finder (.100") to get to the perfect center of 1". Doesn't make sense does it, move .600" to get to .500", but that is how it works because .600" -.100" is .500". The edge finder uses its edge, not its center so that is why it is a little screwy looking.

You can do a lot with these few items.
Hope that helps some.
Ronnie