Like the video. I'd appreciate a follow-up video to see the corrections you suggested and then to repeat the measurements and see if the corrections made a difference.
Agree with johnbewick just above. The 940 has problems. I still have mine because it's the biggest mill I can get into my limited space. My 940 has .0017" runout in the R8 taper. Making fine adjustment on the Z axis is stupid difficult, forget about dialing in another .001". The arm mounted control box will be destroyed if it is too close to the head during Z travel. Gib lock handles on X and Y axis will collide with the machine if not pointed in a safe direction. There is no way to lock power down feed into engagement, PDF can and will disengage at random. These are just a few of the problems. There are many others.
I have a similar machine supplied by Warco here in the UK which Ive had for 15 years, The biggest problem with these machines is the base which is not very rigid and can make tramming across the Y axis difficult, the machine needs to be mounted on as flat a surface as possible with the bolts only just finger tight, pulling them down tight will distort the base causing errors across the Y axis. The wobble you have will most likely be caused by loose gibs and gets worse as the table is drawn to the front because the saddle overhangs the ways and both contact area and support is lost therefore exaggerating any play in the gibs There should be enough slack in the leadscrew mounting to negate any runout in the leadscrew itself once the gibs are adjusted correctly.
The wobble is almost always a bent ball screw or the end work has runout. The Y has a lot toward the support bearing side. If the end work it out more than a bit I can replace the screw. Re adjust it a few times and see if its binding or out of round. Nice square you have. Nice tram video.
Or just throw it in a dumpster and buy a proper mill. I brought one of these some years ago, and all it brought me was grief. Just as you think all the faults have been overcome, something else will rear up to frustrate you. Really just a load of garbage.
Stefan Gottewinter did a really good video about some of his modifications to his Optimum MB4... which is very similar to the Precision Matthews stuff. In his video he did some adjustments to the ball screw mounting surface and installed some improved bearings. If you haven't already seen his video I would recommend it, I bet it'll give you some good ideas for future improvements as well :).
