Dec 27, 2014

The M4MA milling attachment

Sorry for being silent for such a long time, I was really busy with my job, so had practically no time for my basement workshop. However I am still alive, and back to blogging...



...yes, what you see is true. I did purchase a milling attachment for my SIEG C4 machine, after all a worthwhile household must involve at least a lathe and a milling machine, mustn't it? Unfortunately I could not buy it from the same dealer, that's why it is of red colour instead of the same green colour the lathe has, however this fact did not stop me from installing it on the machine. Of course the M2MA also has to be more or less disassembled and cleaned to get rid of the usual conservation grease, and properly re-lubricated during reassembly.
 First I attached the rectangle console onto the bed. When the screws were slightly fastened I adjusted it's parallelism, which is not really so important because the angle of the milling head is adjustable, but I sleep definitely better if they're more or less parallel.
It is far more important to have a firm surface which the "third leg" of the machine will stand on. I speak about the adjustable support of the milling attachment. This is made of a screw and a round cast iron piece which should be twisted in order to set the desired height. However there is nothing on it which could help rotating, so I made a hole on the side of it at the bottom to be able to adjust it with a rod even under load, if necessary. I set up a measurement (the same as described in a former post about the machine stand) to roughly indicate the torsion of the bed caused by installing the milling attachment. If the surface is firm enough, there should not be significant torsion when putting the M2MA on the console. Should there be any, it can be minimised by properly adjusting the support leg.
Now let's make some runout measurements.

 
 The runout of the inner taper is within 0.01 mm, while the runout measured on the shank of a tool fastened into the chuck is 0.04 mm, of course worse than measured at the taper. For precise work the best way is to  use milling cutters with tapered shank. The chuck can also be replaced to a better one if needed.

Here is the very first test milling:


Machining a round piece in the additional chuck:
And finally here is my support plate for mounting different chucks or whatever other self-made clamps:

The special nuts were also machined on the C4 lathe... How wonderful is to have such machines so you can do almost what you want!