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Monarch 612 Spindle removal?

Willray

Aluminum
Joined
Jan 30, 2011
Location
Central Ohio, USA
Greetings Gentlethreadpersons,

I find this pandemic shutdown business is creating opportunities for me to try to injure myself in new and different ways, so I decided to finally bite the bullet and start trying to get the Series 612/1610 that I've been tripping over for a few years, back up and running.

Some day I'll get around to documenting the tragic backstory that leads to me having a 612 in the way and tripping over it, but that's a story for another day.

Today what my 612 needs, is the spindle to move towards the tailstock, maybe 1/2 inch.

(What it /really/ needs, is the High/Low shift fork to come out the front of the machine, so that I can repair the little cam profile piece that's supposed to activate the hydraulic shut-off when in neutral. Unfortunately, as far as I can tell, despite Monarch's near infinite wisdom in most design details, the fork can't be removed without sliding the spindle tail-ward for additional clearance. So, the spindle needs to move).

I don't think this is supposed to be a monumental task.

There are two "lock nuts", one just inside the main bearing set, and one at the outboard end of the spindle. Both are slightly buggered, probably due to some previous idiot not realizing that they're retained by stacked set screws and just trying to beat them into submission. Still, with a bit of love and persuasion, both are free to turn, and have been backed off.

The onboard "spacer collar" was joy to move, due to some damage to both its internal surface and the surface of the spindle, but it's now off as well, and the appropriate discussions have been had with galled surfaces.

The front bearing retainer is detached and loose (and the front cover for the headstock is removed).

The spindle however, seems rather dedicated to staying exactly where it is.

Am I missing something? From looking at the parts diagram, it seems the spindle should now, possibly with a bit of cajoling, slide out the front.
 
No one has removed the spindle on a 612?

Ok, going once, going twice... Unless someone smarter 'n me chimes in with a suggestion that wasn't hatched from insanity, tomorrow I'm gonna cut part G51, the outboard oil slinger, off the spindle.

From what I can tell looking at the parts manual - wish I had a mechanical drawing of the headstock! Monarch's detail drawings are glorious - the oil slinger is supposed to be keyed at the woodruff-key slots occupied by G75. On my fine example of this beast, the oil slinger is pushed completely past the woodruff-key slots - and I don't see corresponding slots in the oil slinger itself.

My current working hypothesis, is that someone wedged a possibly incorrect oil slinger up in there and got it stuck, up against the outboard bearing, and that this is what's preventing the spindle from nudging forward.
 
If you still having problems, give Monarch lathe a call and they should be able to talk you though your issue over the phone. And if you are willing you can buy a complete set of drawings for your machine. Last I hear they were going for about $150.

From my memory, you did everything right. Those locknuts with setscrews that look like a key, usually is what hangs people up.

If you are sure you got everything loose. Put a board on the back of the spindle and give it a good smack with hammer and it should pop loose.

Why does the spindle need to be removed? What damage are you trying to fix.

John
 
Greetings John,

The reason I'm digging into this thing, is that I need to repair the little "cam" plate that lifts up the oil diverter valve when shifting between high, neutral and low.

I'm not entirely sure how long it takes for this to happen, but on mine, the range-shift lever has been shifted so much, that the little tit on the bottom of the oil-valve plunger has "dented" a groove into the cam. The dent increases the attack angle on the cam, making it difficult to switch out of gear and into neutral.

Everything /should/ be grand, Monarch clearly got that it was a wear part, the cam is even designed so that you can just un-bolt it from the shift-cradle, flip it around and reinstall it, and you've got a fresh wear surface available.

It's bolted up through the underside of the top arm of the shift cradle, and _almost_ everything is relieved so that you can just pull the pivot on the shift cradle, and then slide the cradle out the front of the machine after removing the speed selector panel.

But... The stupid slot where that could happen, is about 1/4 inch too narrow. The only way I can see to get the shift cradle out without modifying the machine, is to move the spindle towards the tailstock about 1/2 inch, which will let the shift cradle sneak around the little bump that's in its way and come out. The alternative is to cut just a tiny little relief (about 1/4" deep by 3/4" tall) area in the top right of the window where the speed selector mounts.

I find it astounding that Monarch did not design that section for more facile disassembly. It's so very close.

... in other news, I did cut the oil slinger out - or rather, I cut two grooves in the neck of the oil slinger, and then used a diamond wheel on a grinder to widen the grooves until I could get a much-abused gear puller onto it, and then applied further abuse. Much profanity later I finally managed to break the thing loose and dragged it off the tail of the spindle. The tail of the spindle is definitely scored, which is what was retaining the oil slinger.

Unfortunately, I think there's more damage in there - the spindle still won't move under any sane amount of force. I think the outboard bearing is frozen onto it too.

I'm stubborn, but this just may become a parts machine. Axial and radial runout still look great, and I've got a local place that can regrind the bed for what doesn't seem an insane price, but there are also three gears in the far-back-left corner of the headstock that look like they chewed on something, and with the seeming stuck/scored spindle issues I'm starting to think this is going to cost more time and $ than it's worth.

Bah humbug!
Will
 
It been too long since since I worked on Series 612, but I think there is a simpler way to do what you need to do. But I need to see a drawing to remember. Give Monarch Lathe LP a call and explain what you are trying to do and they will walk you through it. It’s might save you some pain a suffering.
 








 
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