$% ^&^#this turret...I am loosing hair

Here I am on a sunday working on our old QT15. Realigning the turret ebcause it is high a whopping .015"! So I take the cover cap off and the center nut will not come loose (no spanner wrench in the shop). So after fighting with heat, regrinding allen wrenches and a couple of choice new words I made up I have all the parameter bolts off the turret (The large circle on the outside). Now back to the large spanner nut I decide that I will release a little tension by taking the clamp circle bolts off and am down to one that is stripped beyond belief. Wouldnt you know it in a 5 axis machine shop not a single cobalt or carbide drill small enough to drill it out. I dont remember but the spanner nut was clockwise tight...right? Am I on the right track trying to ease tension on it by taking th bolts out of the center bolt circle?

.015 off
i loosen the outside bolt circle (ones in the curvic) and beat that fkr back to where it should be (assuming you pulled the taper pins years ago). There is surely enough play in that spline shaft on a 20 year old lathe to let it go where it has to go.
as far as the drilling
if you go a couple thou. smaller than the across flats of the socket in about a quarter inch then blast it with a chisel you can useualy pop the radius under the head and the head pops right off, regular drill will do it 'specialy if you got a hand full .
didn't see your post till monday morning
next time on a sunday you can call me 309
230...........
3193

A trick I use to gain leverage on the turret for alignment, is to bolt a 1" square bar at least 24" long in one of the OD stations. The bar is sticking outside of the machine of course, and I use a sledge hammer to tap this bar, thus bumping the turret in line.

Oh, you have to loosen the 2 bolts in the big retaining nut in order for it to loosen. I use a hammer and flat punch to peck the big nut using the slots in the nut's OD.

Also you may have to either turn the machine off to loosen the nut, or unclamp the turret. With power on, the turret is being pulled back so tightly it may jam the nut.

Greg

You guys are the greatest! I was hoping the two of you would chime in. Before I call you on the phone lets see if you can guide me a little online. thank you so much for offering! Ok so the center bolts are all bent and I am assuming the tapered pins are long gone but I cannot tell the spanner nut wont budge someone put it on with an impact. We replaced the motor gear a couple years ago and it was cracked all to hell. The two littel retaining tension bolts that go in the small tapped holes in the spanner nut are missing and you can see where they applied alot of torque to the spanner nut. This job shouldnt really be harder than its being. The outer bolts had so much crud in the holes I had to use heat to soften the crud to get them out and I want to clean the holes so I plan on taking the turret out. I tried like hell banging and dinging the spanner socket but she didnt move. I tried a little heat but I dont want to get it too hot for fear of loosing a seal. If you guys could use a little jedi mind magic to loosen the bolt that would be great! Thanks!

gregs probly got the deal on spanner nut
shut machine off to let the hydraulics relax

Well got the turret off and I see 2 of the pins still in. The other 2 are gone. At least I am assuming their were 2 more in the empty holes. At this point I guess I am pulling the couple off and removing the pins. I cant believe the pins would be bent .015"!

If the turret is off .015" the pins will be bent .008" or so. There is normally 2 sets of pins. Curvec to turret and curvec to the turret frame. One or both sets may be bent. They may not look bent unless you roll them on a surface plate with a strong light in back of them. Carefully stone off the raised metal around the taper pin holes. McMaster Carr has metric taper pin reamers if needed.
Now is probably a good time to check the large seal on the turret, and any seals for coolant if it goes thru the turret.

Bill

throw the pins over your shoulder
reinstall turret

I should be taking the curvic coupler bolts out to remove the pins?

Coolant union o-rings

Hey,

Next time you have a turret off be sure and dissasemble the coolant union and replace all of the o-rings, if you let it get to metal on metal it can get expensive, at least add some 3m o-ring grease.
Sorry to hear about all the trouble, now you are a pro, I second the 1" square bar, I use a big dead blow hammer, I am really worried about damaging the spline, I heard those a "Big Bucks"!
Also second on the "throw the taper pins over your sholder", your fix could have been a lot easier!
Hopefully you cleaned out all the old grease on the cervic coupling, get a new nut, if it is missing the tension screws sounds like somebody used locktight to get the sale done.

Glad it all worked out!


LandM1

I should be taking the curvic coupler bolts out to remove the pins?

Click to expand...

you may have to loosen bolts to get pins out
i then look very closely at the bolt circle and try to line it up as centered as i can
when you put the turret back on you can get at the set that holds the curvic in the turret half from the out side(you have to remove most the tooling), loosen them all , snug them slightly, and then tap turret to where it needs to be. tighten everything back up, shut machine off and tighten up spanner nut,tighten up little bolt circle in the spline coupling around spanner nut. recheck centering, replace covers and your done

I agree with throwing away the taper pins, however I would do one more thing. Ream the holes out with a straight reamer to fit two new hardened pins. Make sure the pins have a threaded hole in them so they can be pulled with a slide hammer.

Lube the pins and make sure they fit, then take them out and put them in your tool box. The next time it wrecks, use the pins to align the coupling again. This way the pin holes will not be damaged and the alignment can be easily achieved.