My LMS 5500 (SIEG XS2.7) -- History and Current Problem

[CraigH]

I have and use a 1.25" face mill that uses carbide inserts, on my mini mill. But, and it's a big caveat, I don't use very large DOCs with it: and it's mostly used on aluminum. I have used it on steel and my mill notices it, but does OK as long as the depth of cut is small, .010" or thereabouts.

Milling stuff with holes in it disturbs the mill enough to produce obvious variations in the surface finish around the hole so I try to use the tool before drilling holes into the work.

This is with a 500 watt mini mill and an R8 spindle.

You may have the same LMS face mill that I have. I do not use it much as not much need arises. CW at LMS recommended this over a flycutter. There seems to be some debate on that. Especially since smaller (less that 1/2 inch) are supposed to give a smoother, flatter surface. Not sure about that. Give a mill in perfect tram (is this even possible?) and extremely rigid, either ought to provide a superb finish.

 

[RaisedByWolves]

I have and use a 1.25" face mill that uses carbide inserts, on my mini mill. But, and it's a big caveat, I don't use very large DOCs with it: and it's mostly used on aluminum. I have used it on steel and my mill notices it, but does OK as long as the depth of cut is small, .010" or thereabouts.

Milling stuff with holes in it disturbs the mill enough to produce obvious variations in the surface finish around the hole so I try to use the tool before drilling holes into the work.

This is with a 500 watt mini mill and an R8 spindle.

For experienced users I'm good with this and would like to make a heavy flycutter, maybe 2" for my mini mill strictly for facing with light cuts.


My concern would be someone inexperienced damaging their machine by going outside the already generous recommended cutter size.

 

[homebrewed]

For experienced users I'm good with this and would like to make a heavy flycutter, maybe 2" for my mini mill strictly for facing with light cuts.


My concern would be someone inexperienced damaging their machine by going outside the already generous recommended cutter size.

I have a flycutter in that size category and it does produce a very nice finish. The one limitation is that its large "throw" imposes a significant limit to the size of work you can machine, if you want a uniform finish all the way across. By this, I mean that the entire surface experiences both the front and rear cutting action. If the mill is well trammed this will just be a cosmetic thing.

My face mill has a smaller throw so this is less of an issue....most of the time.

 

[CraigH]

Here is the part (V2.0) that I was attempting to make when the mill deteriorated further and became unusable.

The turning and threading was done on the mini-lathe. Threads are 0.08085 inch OD and 28 tpi.

The milling was accomplished with a 3/8 inch two flute HSS end mill. To get the desired width, the work was traversed 1/8" left of center to 1/8" right of center and to a depth of 0.150" deep.

I do not have a rotary table or dividing head, so after threading the steel milling fixture, I "divided" it by scribing along the three jaws of the chuck and subsequently milling 1/8" x 1/8" slots for locating the three sections in the work to be milled. After indicating the center of milling fixture, I marked a piece of poster board with a pen in the mill head to locate each of the three areas to be milled.

Came out pretty good.