Cross travel

Hello all,

I am still quite content [*] with my mill-drill. With several projects behind me, when I have to think about limitations, it is usually cross-travel that gets tight. One time I had to think fairly hard about spindle-column distance.

Since I am building mostly one-off items that I design myself, I keep the mill's dimensions in mind, and sometimes, for example, make a frame when a single plate might be simpler but doesn't quite fit.

I am starting to see a few situations where a knee mill would be nice to have, but can't yet claim to need one. I sometimes care about depth of a non-through window, and that can be tricky/impossible to measure if the window is small. Presumably, a knee would allow me to make clearance for a measurement and the reliably return to the same depth and keep going. As it is, I try to do a good job of contacting the surface, and as long as I remember to release the lock before feeding downward, I can use the dial to make good relative measurements - it's been more than enough so far.

I am fairly convinced that I am better off with my mill-drill than I would have been with a bench top knee mill. Benchtop machines never quite match the travel I have. With ER collets and some simple rules (not to mention being willing to mill with the spindle more extended than one might like), I get by fairly well. I have had very few setups go completely sour due to limits of the machine (due to limits of the machinIST is another matter).

I have allowed myself to consider what I might want in a knee mill, mostly in case I stumble on a used one, I want to know whether or not to buy it in a hurry. The machine I am about to describe appears not to exist (perhaps just as well), but so far I would probably ask for a 9x36 vertical mill with a 12 inch cross travel. I see some 8x36 machines but they typically have only a 9 inch cross travel. It seems like an awfully big pile of metal "just" to go from 7-9 inches.

It probably is due to the weight of the knee, but why are the cross travels as small as they are? More important, am I missing something that allows one to easily rotate parts 90 degrees to take advantage of the longitudinal travel?


[*] ok, after my 90 Sentra, it's probably the best thing I've ever purchased :)
Reply to
Bill Schwab
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