Monarch 60 feed and leadscrew stopped working

[beckerkumm]

The feed and leadscrew both stopped working on the Monarch 60. I probably self inflicted as i tried the leadscrew reverse on the gearbox of the engine lathe. I should have slowed the spindle down more than I did but when I tried to engage reverse the feed stopped. The lever still slides the dogs in the headstock but there is nothing turning in the gearbox. The feed and screw lever does move the gears to engage either but nothing is moving from the headstock above. Is there a pin that might have sheared off somewhere that Needs replacing. I need some guidance to get started.

The smaller diameter shaft is the reverse and the collar engages in both directions but nothing goes to the gearbox in the last picture.

Thanks, Dave

 

[texasgeartrain]

Inside the headstock, I see the dog on one gear, but i cant see the dog on either side of slider. Could be its just out of view in pic. I forget on the 60 and 61's, if its one or two dogs on each side of slider, pretty sure only on dog per side on my 12ckk. Anyway it would be either just less than 180 degrees or just less than 360 degrees, depending if one or two dogs, for contact with fwd or rev gear.

My first easiest check would be, does qcgb spin when LSR is engaged to either direction and clutch is engaged ?

If no, and head stock dogs are still attached to slider and each gear. . . Then pull an end cover off the left end of lathe to watch the gear train driving the qcgb when clutch is engaged.

 

[texasgeartrain]

B54 being the slider, looks like one dog. And B50 and B56 fwd and rev gears:

 

[beckerkumm]

Mine is a 16" so B75 has one dog on each side and slides to engage OK. End gears run but nothing transfers to the qcgb forward or reverse. I'm running at 5 hz with the lid off to watch what is happening and have the top off the qcgb and don't see any gear running. Dave

 

[TheOldCar]

The play in my LSR assembly sometimes does this. Previous owner thought it was for feed reversing, and at any speed! (He even demonstrated it for me ).
So when I thread, as I reverse to away-from-spindle (lever up) I try to make sure I keep that lever in max upright position until after the clack. I then let go of the lever softly.

There are times I have panicked when the LSR made its way to neutral without me knowing it. Usually the next day after I threaded something.

 

[texasgeartrain]

If the lathe's left end gears are spinning, but qcgb does not. . .Check the last gear you can see spinning in the chain toward driving qcgb, as qcgb should spin.

Could be a sheered key way as you said.

I need to check some pics to remember whats there.

 

[texasgeartrain]

I was messing around with the qcgb in two different threads. Part of the chain to drive qcgb is here in post# 163:

Getting a Monarch Series 61 Back in Service

This is a fantastic thread and great job documenting your rebuild. I love seeing the design of all of these components, amazing machinists, Monarch was. I have a Series 61, 13x30 with a slight dimensional issue, originally planned to have the bed ground + turcite, that project stalled for...

www.practicalmachinist.com

That shaft and gear assembly is receiving output from left end gears, and part of input to qcgb. Two keyways on each end of shaft, seen in post#25 here:

Monarch Series 61, Rebuilding for Improvement

I got the leadscrew end bracket cleaned up, and the bearings for feed rod and clutch rod shoved out: Painted, and I'll be drill oil passages and adding gits oilers to 3 of the 4 bearing holes. Exception is the leadscrew reverse. That slides in and out, besides rotating, so easy enough to...

www.practicalmachinist.com

Now if you back up to post#24, you can see where that shaft is missing from housing. Looking diagnal from there, you just barely see another shaft with gear removed, and another key slot.

My guess would be the very last gear in the chain that spins when powered up, is where the sheered key is.

 

[beckerkumm]

The problem became obvious when I took the end cover off ( and my head out of my ass ). The 25T gear sheared off two teeth and then the 75T gear dropped down so nothing ran the feeds. The gear looks like cast iron to me or the steel is chrystalized if that makes sense. It doesn't look hardened though.

If anyone knows of a replacement, I'm happy to pay for my screw up. New gears can be had but will require modification to the bore and the thickness of the teeth. The DP is 10 and I think the PA is 14.5 but hopefully someone will verify. The two keys are .25 and I can broach them although I'd like an opinion as to whether two are necessary. Are teeth normally the weak link in the system?

Dave

 

[texasgeartrain]

One of my best sources for used 60/61 parts has been Mike Thomas:

mikethomas

I think he has a minor specialty going with buying, selling, and fixing 60/61's. He had a complete head stock and most of a qcgb as I recall. I'll pm you his phone number, send him a text.

In the past several months, a fellow from Ohio was trying to either sell outright, or part out a 61 also, might back track some threads here to find it.
edit* that other one is here:

61 Part Out

This is a parts Lathe. The bed is junk. I have $2,000 into this unit. I will part it out IF I get $2,000 worth of parts commitment. I've had a few people ask me about it so I'm going to go ahead with part out if applicable.

www.practicalmachinist.com

 

[mikethomas]

I had those gears. I hope I did not throw them away. Let me check.

Mike

 

[mikethomas]

I found it! Let me know.

Mike

 

[beckerkumm]

Mike is a great guy and agreed to send me some gears and clutch parts for the Monarch. In the meantime I modified a stock 25T gear for a temporary fix. Also made some shelves for the KDK holders that came with the lathe. There are at least three drawers more of them but these are the most used. Dave

 

[m-lud]

It's great that Mike came through with those gears. That could have been really tough to find those. I know T.G.T. got some parts for his series 61.


mikethomas

 

[beckerkumm]

The 25T and 50T can be modified from stock but the 75T would need to be made from scratch so I'm happy to get that one and the clutch parts as they are hard to replace. The gear that broke looked kind or grainy at the break as if the steel was compromised. I've seen broken bolts that looked like that too. Dave