I finalized machining the gibs. Added dimples on the back side to accomodate ball ended adjustment setscrews. This makes gib adjustment super easy. I also had the gibs re-ground on both sides to ensure flatness.
An oil flow restrictor had to be made to ensure proper oil flow to both the gib and the dovetail. This was made out of POM. The oil passage is 0.7mm in diameter.
I also milled oil channels in the oposite dovetail.
Had some trouble with the Z axis screw. The bearing block was not aligned with the Z nut. It was 3mm off and was binding at the top. I elongated a few mm the bearing block screw holes and now the Z can be adjusted easily.
Otherwise the mill is coming along just fine. Tomorrow I will reattach the electrical cabinet and finish installing the oil lines and then cut the first chips.
First project will be making a mounting block for an Ikea Jansjo LED lamp.
Some weeks have passed since I started using the machine. In the mean time first parts have been produced and I would like to give some conclusions to this review.
I made a nice pair of vise clamps out of hot rolled steel. After machining the clamps were sandblasted and cold blued.
Machining in steel was easy enough. The mill seems to be solid and can easily mill steel. Tried different endmill combinations: 6mm, 8mm, 10mm and 12mm with good results.
I also tried to mill a piece of aluminum also with good results.
The central oiling system works like a charm. I still need to install the one way valves on all the circuits. While it works without the valves, the pump must be active longer so oil can reach the Z axis and while doing this is squirts too much oil in the X and Y (messy).
Conclusion:
PROS: Solid machine for it's size. Very nice features (belt drive, BT30 spindle with tool quick change, 1.5 kW AC induction motor with VFD, counterweight for the head). No quill, therefore easier to CNC. Holds good tolerances.
CONS: Some design and execution mishaps which require a bit of TLC. But we are talking china, therefore not totaly unexpected. Here I refer to the oiling concept and the gibs. No quill. Milling and drilling with the head can be done but it is not pleasant. Also the paint is chemically compatible with...almost nothing. benzene softens it instantly, methilated spirits instantly makes it bouble and peel off. Some epoxy or polyurethane paint is due in the future. Benefit of the crappy paint is that it can be stripped off with no effort.
So, for me I consider it a good buy and I recommend it to anybody who wants to CNC it.
If one wants to use it as a manual mill, then please get one with a quill.
Also, for CNC conversion stay away of the more expensive version with power feeds. You will throw the cheap and weak steppers and drivers to the bin. For the price difference one can buy really nice hybrid steppers and drivers.
Re: Optimum MH25V
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