I am moving into concave faceting I need a recommendation for a made in america concave facet machine from someone who knows about concave faceting. Thus far I am most impressed with the OMF machine. I am not impressed with the 220V machines made outside the US. The Ultra tec is nice but twice the price of the OMF Please advise..Today is Jan 13, 2019 please reply soon. Diamond$ thanks in advance.
I started using the OMF back in 1995 and recently upgraded to the Ulta Tec Fantasy machine. I have a left mast Fac-Ette and can say it works, but is awkward since the controls are on the far side of the machine. In that configuration the markings for speed or angle of the OMF are not visible from a working position. If you are using right mast machine that is supported by the OMF options, then you should probably be fine.
I did not find the OMF right for doing other than straight concave work. Because the stabilizer is connected to the cutting unit which rotates, I did not see an obvious way to get repeatable angles if you want to cut concaves not parallel with the dop. Plus with my Fac-ette, the mast would have to move along the track (problem due to the type of track provided which I think was corrected later models) or else the cutting unit would need to move along its track (a problem because its screw is underneath the base.) I have no idea if this is an issue with other faceting makes.
I am still getting used to the UT. Since they make machines to work with left mast faceters, controls are in the front. The stabilizer for the dop is attached to the block holding the mast. The cutting unit moves and rotates without disrupting the alignment of the mast thus it is easy to make repeatable cuts. It does take more attention to place the stone on the mandrel since the cutting unit moves back and forth, not just the mandrel as is the case for the OMF. Of course, the fantasy machine has a lot more options than the OMF — I’ve got more learning before I get to much of that.
The cost of the UT compared to the OMF is definitely a consideration. If you have not done any concave work, it may be a good place to learn some basics if you have a limited budget. The price difference will get you a lot of practice rough!