[The_bluester (Paul)]

I can understand the frustration, even some simple commercial gear is not really up to snuff. Discussing your trials and tribs sent me out to my lathe to whack the dial gauge on a heap of mostly commercial off the shelf bits I have. A quick machine on both ends of an old socket to make sure it was as parallel as I could make it followed by rotating it in the chuck and checking again says my lathe is not perfectly flat, probably 10 microns or so away (It is just a cheap Chinese thing I bought to shorten bolts and make non critical stuff for my race car etc) but whack the commercial extension tubes in and suddenly I was seeing 25 microns of runout. Put one of the "well known brand" plastic spacing adjusting rings in between two extension tubes and suddenly it was 100 microns and more!

I want a better lathe now so I can make my own bits and if they are not straight, know who is to blame...

That said, for all the issues, the first light image of Ara is pretty flash and as Mike said, nice Lobster!