stoneaxe
Stainless
- Joined
- Mar 2, 2010
- Location
- pacific northwest
The VN 12 has three main limitations as a drilling machine- no quill, the limited space between the spindle and table, and the lack of VN 5c toolholders. When used as a vertical milling machine, this is not too bad, as the end mills etc are short.
Where it really becomes a problem is drilling when the holes are non standard size, and may require reaming. Screw machine drills eat less space, but the reamer is long. I have used the mill with the head flopped horizontal, and drilled with the Y axis, moving the ram back to gain space. That works well in some circumstances.
This does not solve the odd size toolholding problem. It seems to be the most problem with smaller sizes , under 1/2". Drill chucks eat a lot of space, are not very accurate, and the long extension just adds to any runout the spindle may have. VN collets are not impossible to find, but getting the right odd size is difficult. And when set up, switching collets means having to drop 3" or so down to get the collet out of the spindle. That can be a problem if working close to the limits of travel.
So what I am going to do is to use a ER16 collet holder on a long 1/2" straight shank,in a VN 1/2" collet. This will give a lot of flexibility with small drills and reamers. The collet holder body is only an 1 3/8" in length. Down side here is a max of 7/16" capacity.
Also, I am going to make an ER 20, or 25, collet holder with a VN 5c body, to go directly into the spindle. ( I asked Hardinge about this, but the price was close to $900.) The one I will make will not be hardened, as I do not have the ability to do so- but given infrequent use 1144 stress proof ought to last a long while.
This should eliminate the problem of obtaining the correct VN collet sizes, and help greatly with the vertical travel limitations.
I realize it was designed as a mill, and it is being used outside of it's sweet spot- however, it is what I have for now.
Thoughts on this plan?
Where it really becomes a problem is drilling when the holes are non standard size, and may require reaming. Screw machine drills eat less space, but the reamer is long. I have used the mill with the head flopped horizontal, and drilled with the Y axis, moving the ram back to gain space. That works well in some circumstances.
This does not solve the odd size toolholding problem. It seems to be the most problem with smaller sizes , under 1/2". Drill chucks eat a lot of space, are not very accurate, and the long extension just adds to any runout the spindle may have. VN collets are not impossible to find, but getting the right odd size is difficult. And when set up, switching collets means having to drop 3" or so down to get the collet out of the spindle. That can be a problem if working close to the limits of travel.
So what I am going to do is to use a ER16 collet holder on a long 1/2" straight shank,in a VN 1/2" collet. This will give a lot of flexibility with small drills and reamers. The collet holder body is only an 1 3/8" in length. Down side here is a max of 7/16" capacity.
Also, I am going to make an ER 20, or 25, collet holder with a VN 5c body, to go directly into the spindle. ( I asked Hardinge about this, but the price was close to $900.) The one I will make will not be hardened, as I do not have the ability to do so- but given infrequent use 1144 stress proof ought to last a long while.
This should eliminate the problem of obtaining the correct VN collet sizes, and help greatly with the vertical travel limitations.
I realize it was designed as a mill, and it is being used outside of it's sweet spot- however, it is what I have for now.
Thoughts on this plan?