On Saturday 03 May 2014 21:27:59 andy pugh did opine: > On 3 May 2014 13:53, Gene Heskett <[email protected]> wrote: > > Looks good Andy, but the 9x looks as if it has 3x the room to do it > > in. The gibs on the 7 are maybe 4mm thick, total. 3 hex head holdup > > bolts, 2 jack screws between them. > > That's posh! My 9x had no jacking screws, just three cross-head > screws. The adjustment was by the screws being "not quite tight". Very > nasty indeed, especially as they ran on a painted surface.
I got a better look at it today, not hex head, but socket head, and they clear the drive screw about 1/16". IOW, no way in hell to do any fine tuning. Then to top that, I was grinding the 8mm screw down to 8mm so it would fit the bearing boss, got it within 20 thou & switched to a diamond disk with very slow feed rates & per cycle advance of .0005". Checking my progress, I found a taper, so I put a compensation taper in the slow stroke, measured taper, added some more, measure taper, and about 30-40 reloads later as I kept adding taper, I had .018" of taper in 2.25" of screw, BIG at the chuck. Not correct, but it now fits the bearing boss ok. The only thing that can do that is the head is slewed off the line of the bed and carriage travel. So when I write the code to do the extension for the X screw, I'll start with a 10 thou per inch taper, cutting smaller toward the chuck. Thats way more out of kilter than lifting the headstock and slipping some alu foil on the front of the v-way on the left end, and the back of the v- way on the right end. It will take some serious shimming. Shimming that will probably never get done as its at least 2-3 hours disassembly to just get at its mounting bolts in the bottom of the bedway. I can write corrective code easier. Typical I guess, I have not found anything truly square on this thing yet. Even the v-way angles and the groove to fit it in the bottom of the carriage were out, probably 5 degrees! Tightening a front gib screw would lift the rear of the carriage about 3/16" off the back of the bed! That I fixed for the most part, teasing the angles a bit in the mill years ago. It was one of my first machinery buys, and is pushing 18 yo now. I'd hope QC has been improved over the years. Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS ------------------------------------------------------------------------------ "Accelerate Dev Cycles with Automated Cross-Browser Testing - For FREE Instantly run your Selenium tests across 300+ browser/OS combos. Get unparalleled scalability from the best Selenium testing platform available. Simple to use. Nothing to install. Get started now for free." http://p.sf.net/sfu/SauceLabs _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
