Carriage stop question?

[LX Kid]

If I put a carriage stop on my Atlas 618 and the carriage runs into the stop, what is the series of mechanical events that happen? Do the gears strip? What are the results? Thanks

 

[Technical Ted]

I'm not sure about your lathe, but any of the lathes I'm used to I would never run the carriage up to the stop under power feed. I always disengage the feed short of the stop and run the carriage up to it by hand. Some lathes have auto kick out, but I would doubt an Atlas has that feature.

If you're lucky a shear pin would break. If you're not lucky hard to tell what might fail including stripping gears in your feed gear box or carriage, shearing keys, or whatever the weak link is.

Edit: if you're really lucky and the carriage stop isn't tightened down well, it might just bind things up bad and push the stop down the ways.... not good and I certainly would never purposely treat one of my machines that way!

Ted

 

[RJSakowski]

I have an Atlas/Craftsman 6 x 18 with a 3/4 hp motor. I generally adjust the belts so they will slip before the motor stalls. I have a carriage stop but I rarely use power feed or do threading on that lathe. I have stalled the lathe on heavy cuts on numerous occasions with the belt slipping but no damage done.

What will actually occur depends on a large extent on what pulley arrangement you are using. If you are running with back gearing and the lowest speed pulley arrangement, you can transmit a lot more torque before the motor stalls. What happens will depend on the condition of the various components. Worn half nuts or lead screw threads are more likely to fail. Faster feed rates or more coarse thread pitches create a higher load on the gear train. Personally, I wouldn't depend on a hard stop when threading or power feeding. If you must use it, set the lock so the stop moves before any damage is done.

 

[MrWhoopee]

My SB Heavy 10 has a disc clutch on the feed engagement that will slip if the load is too great. I believe the 12 in. Atlas has something similar, don't know about the 6.

 

[Nutfarmer]

With all the zmack in an Atlas if you power it up to a hard stop on the carriage stop things will break. The feed rod support on the right side would be the first to go. Like Ted said always come up to the stop by hand. Disengage the feed before the stop.

 

[benmychree]

With all the zmack in an Atlas if you power it up to a hard stop on the carriage stop things will break. The feed rod support on the right side would be the first to go. Like Ted said always come up to the stop by hand. Disengage the feed before the stop.

Yes, I can attest to that! I did that on a friend's father's Atlas back in the mid 1960s, and the feed rod bracket on the right hand end was the casualty, luckily a local auto parts house was able to order an new on for me, so no hard feelings!

 

[Uglydog]

I like to keep both a wide and fine point sharpie at the lathe, and choose accordingly.
I mark at the lathe bed where the carriage travel to end and stop as identified above take her out of PF as she approaches the line.
Then carefully manually feed her to the line.
The markings are easy to remove.
Works for me....

Daryl
MN

 

[Technical Ted]

For those who don't like to use or don't have a hard stop you can also buy one of those magnetic backed dial indicators. They work well. I have one and use it when I have a reason to. Very handy thing to have from time to time.

IIRC, mine is a Shars, but they all do the same job.

Dial Indicator and Magnetic Back 1"/0.001" Anytime Tools | eBay

Find many great new & used options and get the best deals for Dial Indicator and Magnetic Back 1"/0.001" Anytime Tools at the best online prices at eBay! Free shipping for many products!

www.ebay.com

I especially like using mine when right hand internal threading up to a shoulder (blind bore). Gives you a nice visual aid to know when to disengage the half nuts. There are plenty of other reasons to use one as well...

Ted

 

[woodchucker]

For those who don't like to use or don't have a hard stop you can also buy one of those magnetic backed dial indicators. They work well. I have one and use it when I have a reason to. Very handy thing to have from time to time.

IIRC, mine is a Shars, but they all do the same job.

Dial Indicator and Magnetic Back 1"/0.001" Anytime Tools | eBay

Find many great new & used options and get the best deals for Dial Indicator and Magnetic Back 1"/0.001" Anytime Tools at the best online prices at eBay! Free shipping for many products!

www.ebay.com

I especially like using mine when right hand internal threading up to a shoulder (blind bore). Gives you a nice visual aid to know when to disengage the half nuts. There are plenty of other reasons to use one as well...

Ted

funny , I used to think so ... but I got so fed up with the magnetic indicator losing my position. So today, I made a new holder. Almost finished, I just have to make a new bolt, right now using a hex .. I made it as a quick on /off. My hard stop dial type is a pain to get on and off. So I made this to get on off quickly.

Also may throw it in the tumbler.. Looks good with the fly cut but my greasy hands make it slippery, so may prefer the more matte finish from the tumbler.

 

[Technical Ted]

funny , I used to think so ... but I got so fed up with the magnetic indicator losing my position. So today, I made a new holder. Almost finished, I just have to make a new bolt, right now using a hex .. I made it as a quick on /off. My hard stop dial type is a pain to get on and off. So I made this to get on off quickly.

Also may throw it in the tumbler.. Looks good with the fly cut but my greasy hands make it slippery, so may prefer the more matte finish from the tumbler.

Well, that just goes to show everybody's mileage varies! I've never had that trouble with mine on my lathe ways, but every situation/machine/usage is different. It's nice to have different tools in your toolbox so you can use what will be to your best advantage for different situations and setups.

Ted