upgrade motor for Micro mill?

[phantomcow2]

I have a Harbor Freight micro mill which is in the process of getting a CNC conversion.
Right now the motor is a 1/5hp, as it is labeled. That is alright for the size it is but I have a Y axis extend kit coming in this week, and when little machine carries it in november, it will have an X axis extend kit which increase X travel quite a bit. I will be filling the column with concrete, and some of the head, for the extra mass.
All of this extra work area makes me want a motor with more heft, perhaps 1/3 or even 1/2HP.
Has anybody ever changed a motor frm one of the SIEG mills to a more powerful one? What are your experiences or comments

[musicmkr]

You might have better luck posting this in the "Benchtop Mill" forum.

I have a Harbor Freight "Micro Mill" and have also thought about swapping the motor, but as of right now I have not found a reason to. It seems to do everything that I need it to do quite well.

Realize that when you do you'll have to replace the motor controller as well, and that can end up being the expensive part.

By the time you buy the Y extension, X extension, new motor and controller, you could have just bought a larger mill. If you were to add more power to the spindle remember that the column is still the one designed for a 1/5 HP motor, so you'll start having problems like chatter.

[totally_screwed]

Originally Posted by phantomcow2 I have a Harbor Freight micro mill which is in the process of getting a CNC conversion. Right now the motor is a 1/5hp, as it is labeled. That is alright for the size it is but I have a Y axis extend kit coming in this week, and when little machine carries it in november, it will have an X axis extend kit which increase X travel quite a bit. I will be filling the column with concrete, and some of the head, for the extra mass. All of this extra work area makes me want a motor with more heft, perhaps 1/3 or even 1/2HP. Has anybody ever changed a motor frm one of the SIEG mills to a more powerful one? What are your experiences or comments

I'm not sure how the X1 would cope too well with a larger & heavier motor.

I suspect that with the Sieg X1 Super [Micro Mill], adding a more powerful [and considerably more massive] motor may well have undesirable effects. This may also be true of the X2. Since it is the head that rises and falls with these mills, this additional mass will cause additional loading to the rise & fall mechanism and cause additional cantilever stress & wear to the dovetails on the column. That is unless you can modify the motor mounting so that either its weight bears directly on the column rather than the head. An alternative is to add a counterweight mechanism or gas spring to compensate for the increased load.

The increased frequency of head movements resulting indirectly from CNC conversion, means that the dovetails are likely suffer greatly increased wear.

The same has to be said regarding filling the head with concrete.

Filling the column with concrete does not have the same implications.

There is always the question, of precisely why you require a more powerful motor?

One reason for a larger motor is presumably the ability to take larger cuts, or increased feed rates, however this implies increased cutting forces and cutting induced vibration.

The X1 may neither be rigid enough for your larger motor, nor engineered for the additional weight.

Background
I have a Sieg X1L Super [with the longer table] and I intend to convert it to CNC, but one has to realise that these machines are low-cost and require a fair bit of tinkering to get the most out of them.

Let us know how it all works out.

Good luck!
Chris