Grizzley G0755 5 minute quill removal overview and photos

Vintage Indian Chief

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First of all scroll thru photos as I have captions describing that step.All it takes is removal of three fasteners and backing the quill stop adjuster from pointer nut.Quill is then free to remove from machine.
1) Position quill over wood block in vise with quill extended 2-3 inches down almost on block.
2) As per owners manual see quill return spring adjustment.Slowly release spring tension and quill will ease down to contact block.
3) Remove spring package and brass colored screw.
4) See photo to remove one 5 mm set screw that the locks the second set.Insert wrench and find second set and turn it 10 rounds counterclockwise.Do not remove this one.Its purpose is to keep quill aligned in machine head.
5) Move to right side see pics to decide how much of quill feed assy.you want to remove.Note you can remove whole assy.in its entirety after removing two 6 mm socket head screws.
6) You can either manually or with machine power raise head to top limit switch.Quill is ready to remove.5 minuets or less.IMG_0199.JPGIMG_0172.JPGIMG_0178.JPGIMG_0204.JPGIMG_0179.JPGIMG_0175.JPGIMG_0206.JPGIMG_0182.JPGIMG_0185.JPGIMG_0194.JPGIMG_0195.JPGIMG_0196.JPGIMG_0197.JPGIMG_0198.JPG
Final assembly and ready to go back in reverse order.Two hours total time .
 
A great write-up! I'm sure it will make the job for some 755 owners much easier.
 
Thank you for the write up.
 
Just a caution about greasing tapered roller bearings for this application. It is recommended that you NOT pack the entire bearing with grease as this will result in overheating at high speeds. Precision tapered roller bearings typically require you to fill about 1/3 of the bearing space (the rest of the bearing is left empty) and then do a run in to distribute the grease evenly.

Not a criticism but a curiosity. Was there a reason for polishing down the spindle on top to provide a slip fit for the bearing? Typically, the bearing fit is only a light press fit (maybe a few tenths) in this area that accurately locates the bearing's inner race.
 
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In reply The spindle in my machine after ten minuets on highest speed would get so hot you couldent hold your hand on the R 8 end.To address that issue spindle bearings need to be adjusted,two ways to do it.Either build a spacer to set bearing preload (or clearance )and press bearing on, spanner nut tightened and even torqued or slip fit the top bearing and adjust with spanner nut.After reassembly I have ran machine for an hour and R 8 end is slightly warm.Im not sure these bearings are precision grade?Icouldent find any numbers on them.The bearings are not sheilded or spacered as a Bridgeport spindle is.Cheap way to build a machine.


Mike
 
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As I said, not a criticism. I have to wonder why the spindle got hot with the original set up. There are usually three reasons a spindle gets hot. One, the bearings are shot; two, the bearings are over-packed with grease and three, excessive preload is being applied to the spindle nut on top.

To my knowledge, there is no way to ensure proper preload on these spindle bearings beyond measuring temps at the bearing during run in. Seems sort of primitive.
 
To my knowledge, there is no way to ensure proper preload on these spindle bearings beyond measuring temps at the bearing during run in. Seems sort of primitive.

There probably is, but nobody is going to have a torque wrench with a 3" pass through center in hobby machining.
 
Haven't seen anything even referring to torque settings for spindle bearing preload. Setting by resulting bearing temperature, yes, but not torque.
 
Lets go back to my main issue.If I had done nothing to fix my spindle temp. the bearings would not live long.I have a complete machine shop with a J head and a CNC Bridgeport.These hobby mills cant be compared to these mills and nor should they be.You get what you pay for.Having semi retired I still have a hand in running the other business and do some machining at home hence buying the Grizz. G0755.Also purchased a G 0750 gunsmith lathe.TIG welder,presses etc.In my case the top bearing press fit was over.001 inteference.With this much press how do you achieve proper preload?Hit and miss method at best.Torque definition is a twisting force that tends to cause rotation (as applied to a spanner nut to reach a desired spot).After polishing spindle to suit ME,I reassembled dry,torqued spanner tight scribed a witness line on nut and quill, backed spanner nut off until I found end play ,scribed line and set spanner witness mark to the center.As Mikey posted grease on precision bearings is to be 30 % of space to be filled.I am not convinced these are precision bearings to begin with.Timken specs. wheel bearing grade to be around .0005 runout,my spindle runout is .0004.In conclusion I made a batch of T nuts ,no heat ,no chatter machine repeated to my satisfaction.BTW I use high end coated end mills so I ran the mill at the highest spindle speed and agressive feed.If I ever need to adjust the bearings its a simple matter as in the 5 minute quill removal.Next on the list is changes to the G0750 lathe.
 
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I need to regrease the spindle bearings in my PM727m and this looks very much like my machine. 3 questions;
I assume i need to drain the gear oil first, or is it in a completely different compartment?
Pulling that spring return looks like a bear (more so putting it back on)..what says you?
Are there any gaskets/seals that i should have on hand prior to start?
Nice write up!
ALSO...I saw your avatar...i LOVE Indians. Nice bike!
 
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