[4]

Don't run the boring bar into the chuck jaws on the end of the hole

  • Thread starter Deleted member 43972
  • Start date
[3]
[10] Like what you see?
Click here to donate to this forum and upgrade your account!
D

Deleted member 43972

Guest - Please Register!
Guest - Please Register!
#1
Don't run the boring bar into the chuck jaws on the end of the hole cause you're watching the dro and not the work...

IMAG0893.jpg
 

mikey

Active User
H-M Supporter - Gold Member ($25)
Joined
Dec 20, 2012
Messages
4,377
Likes
4,736
#2
The boring bar equivalent of the arc of shame, where you run the compound into a spinning chuck - you are not the first, won't be the last.

Thanks for starting my day off with a smile, Shawn!
 

higgite

General Manger - Proofreading Dept.
H-M Supporter - Gold Member ($25)
Joined
Aug 15, 2013
Messages
831
Likes
873
#3
I, for one, would never be so careless as to commit either of the rookie mishaps that you two guys described. I'm much more diligent than that. But, let’s NOT talk about running the boring bar past the inboard end of the work, past the spacer/standoffs (untouched) and into the spindle flange opening (not untouched). A verboten subject that one! Don’t anyone EVER bring it up again!

Tom
 

mikey

Active User
H-M Supporter - Gold Member ($25)
Joined
Dec 20, 2012
Messages
4,377
Likes
4,736
#4
I smiled twice this morning - thanks, Tom!
 
D

Deleted member 43972

Guest - Please Register!
Guest - Please Register!
#5
To be fair... I only kissed the jaw. One impact, under manual power. Just .001" past the mark....
Odd shaped plate in the 4 jaw boring an opening. Didn't notice one of the jaws was just peeking through the edge of my hole.
 
D

Deleted member 473

Guest - Please Register!
Guest - Please Register!
#6
My last blunder I can recall was similar, was a threading tool that held the triangle shaped insert on edge. TNMA I recall? Well anyway threading up to a shoulder, cutting a 1"-8 thread, yes there was a thread relief, but running at 160 RPM, didn't give you much time to disengage the half nuts and wam! Pushed the work piece up into the chuck and side swiped the tool and pretty much wiped the insert off and destroyed the tool holder. Had to buy another one at about $100 a pop! This happen on a 16" Axelson with a CA size tool post and over 7-1/2 HP doing the damage!
 
D

Deleted member 473

Guest - Please Register!
Guest - Please Register!
#7
Another goof I did was run a 3/4" diameter end mill into the work piece, rapidly hand cranking the table, and bam! Snap off that end mill like it was nothing. Old heavy 9-J Gorton mill didn't miss a beat and kept on running!
 
D

Deleted member 43972

Guest - Please Register!
Guest - Please Register!
#8
Jeez... Ida probably crapped my pants...

Edit, referring to the lathe crash.
 

RJSakowski

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Feb 1, 2015
Messages
3,577
Likes
4,130
#9
Shawn, you have discovered one of the major drawbacks of using a DRO. While they are convenient to use, they take your attention away from the work. Kind of like texting while driving.
 

brino

Active User
H-M Platinum Supporter ($50)
Joined
Jan 2, 2014
Messages
3,458
Likes
3,484
#10
One impact, under manual power. Just .001" past the mark....
Does anyone else hear Maxwell Smart saying "Missed it by that much!"
-brino
 

wawoodman

himself, himself
H-M Supporter - Gold Member ($25)
Joined
Mar 19, 2011
Messages
931
Likes
711
#11
We need a "big owie" smiley!
 

Mach89

Registered
Registered
Joined
Jan 12, 2017
Messages
70
Likes
143
#12
I managed to stall out the mill at work with a 1" end mill. Was going to make a facing cut using the Y axis power feed. Well, the Y power feed and the one for raising the table are pretty close together. I grabbed the wrong one and rapid traversed the table up, shoving the part hard against the endmill. I had the spindle in high gear, as slow as it would go (only because low gear is screwed up) and it came to a belt screeching stop. But it didn't break the endmill.

Sent from my SAMSUNG-SM-G891A using Tapatalk
 
D

Deleted member 473

Guest - Please Register!
Guest - Please Register!
#13
Jeez... Ida probably crapped my pants...

Edit, referring to the lathe crash.
Believe me, you react super fast! Then crap later! :crush:
 
D

Deleted member 43972

Guest - Please Register!
Guest - Please Register!
#14
I've considered rigging up some kind of e-stop brake. Currently I only have the paddle switch for forward/reverse.
When you're crapping your pants there can't be enough e-stops around... I know this from 15 years of factory work on production lines prone to crashing, even with e-stops every 10 feet, there's never one close enough.
 
D

Deleted member 473

Guest - Please Register!
Guest - Please Register!
#15
Even on newer lathes equipped with foot brakes, And I've operated a few over the years, you still can't react fast enough to push your foot against the foot brake to stop the lathe! The nice thing about the Axelson lathe, you can reach up and grab the clutch lever and shove it into neutral or reverse quicker than fumbling around hitting the foot brake. Your mind is trained to work with your hands when operating the lathe. When you try to throw in your feet to maneuver a lever for a sudden stop, your mind is not fast enough to react because you mind is concentrating on hand movements not foot movements at that split moment. And if you are like me, with rheumatoid Arthritis in my legs, I don't react and move like I used to. So those e-stops spaced every ten feet apart won't do a thing for me but look pretty on their mounts!
 
D

Deleted member 43972

Guest - Please Register!
Guest - Please Register!
#16
Fair enough. The line I ran was 100~ feet long and employed 6 people. It was composit spiral winding. Cardboard tubes basically. A backstand with 15 rolls of paper, the winder where all the paper gets wrapped around a mandrel (my job/operator), an automated cutter, and several packers.
On my winder, myself and the manager set up a trip line e-stop under the machine, instead of stepping on something you only had to kick your foot forward. I was quick with that. Snapped the line off countless times kicking it too hard (hard not to get mad when someone blew the line up cause of a dumb mistake)
Over the years, the kick line remained, but we had set up light curtains around the drums. Major in-line running pinch points from a winding belt. It was easy to stop the machine by throwing your hand past that too.

In any event, any addition of a panic button on my machine would be an improvement over the nothing I currently have. The circuit is the easy part, figuring out how to brake the motor/spindle is another story...
 
D

Deleted member 473

Guest - Please Register!
Guest - Please Register!
#17
Hey, I've thought about a trip line setup on the lathe.

Let it trip when your body gets about halfway around the chuck.:eek:

But seriously, it's a thought in the back of my mind to do so some day. Just trying to figure out a position to put it in.

One thing I did on a lathe many years ago. I installed a Warner clutch-brake module on the input shaft of the lathe. I put the push button control on the right side of the apron so you could slap the stop button quickly. Worked out nice. Pretty expensive to do today in the home shop environment.
 
D

Deleted member 43972

Guest - Please Register!
Guest - Please Register!
#18
Let it trip when your body gets about halfway around the chuck
Oh we had that covered too. There's a limit switch with a 4" stick on it positioned right above the mandrel in the infeed area. So if you got tugged in your body would hit it. It had only ever been used once... a female operator was wrapping the paper around the mandrel on setup/startup, her hand got caught. Took the tips of her fingers off before the machine stopped... but that's what happens when you put your hands where they don't belong. Never happened before or since, in 105 years of the company's history...
 
D

Deleted member 43972

Guest - Please Register!
Guest - Please Register!
#19
I'd take suggestions on how to brake the movement if anyone has any. I don't think I'm interested in changing the motor out for one with a brake. Too expensive. Personally, I'm thinking of something along the lines of a bicycle brake disc/caliper design, with a latching electric caliper of some kind......
Thoughts?
 

francist

Active User
H-M Supporter - Gold Member ($25)
Joined
Sep 5, 2013
Messages
1,054
Likes
1,598
#20
Wonder if a solenoid would have enough throw. Fooled around with bikes alot and the caliper brakes don't require much movement to draw tight. Whether they would have enough clamping force to do anything is another matter. Asco Red Hat solenoids are pretty reliable.

-frank
 

sanddan

Active User
H-M Supporter - Gold Member ($25)
Joined
Jan 22, 2012
Messages
645
Likes
641
#21
Shawn, you have discovered one of the major drawbacks of using a DRO. While they are convenient to use, they take your attention away from the work. Kind of like texting while driving.
That's one reason why I use an indicator for a carriage stop instead of the DRO. I like the feedback of the needle sweeping up to zero.

Now, lets not talk about busted parting tools! I have several on my personal wall of shame.
 

mksj

Active User
H-M Supporter - Gold Member ($25)
Joined
Jun 12, 2014
Messages
1,897
Likes
2,316
#22
Why not just set up your hard stop if you have a feed clutch? I always do this even with an electronic stop system, I always assume something is going to fail or at my age a brain fart (like honey what are you cooking me for dinner, turn head .....bam destroyed insert).
 
D

Deleted member 17524

Guest - Please Register!
Guest - Please Register!
#23
If I know I am going to bore thru and come close to the jaws I use a sacrificial plate between the jaws and the part to be bored.

"Billy G"
 
D

Deleted member 43972

Guest - Please Register!
Guest - Please Register!
#24
I don't have a carriage stop. Now that I have a mill that's on the project list. I always use the clutch. If I'm boring and I know the hole is smaller than the bore of the chuck I don't usually worry about spacers. The part was the motor mount for the belt conversion kit
IMAG0898.jpg
Narrow in the middle. The chuck jaw in the middle was a bit closer into the center than I realized.
 
D

Deleted member 43972

Guest - Please Register!
Guest - Please Register!
#25
Wonder if a solenoid would have enough throw. Fooled around with bikes alot and the caliper brakes don't require much movement to draw tight. Whether they would have enough clamping force to do anything is another matter. Asco Red Hat solenoids are pretty reliable.

-frank
I was also thinking about pneumatic. My 60 gal compressor is always charged. So, there's always air available. I also have a valve solenoid. It has liquid fittings on it, but it's also rated for air and gas. So, all I'd have to sort out is the actual brake
 
D

Deleted member 473

Guest - Please Register!
Guest - Please Register!
#26
Just think, air brakes! like on a truck. Love the sound they make.:high 5:
 
D

Deleted member 43972

Guest - Please Register!
Guest - Please Register!
#27
PPPFFFFFSSSSHHHHHHHHHHH. lol
 
D

Deleted member 43972

Guest - Please Register!
Guest - Please Register!
#28
Well there it is...
If you look closely at the last picture, you can see the line where the new piece is threaded onto the old piece.
I'm glad I salvaged this...

IMAG0908.jpg
IMAG0909.jpg
IMAG0910.jpg
IMAG0911.jpg
 

intjonmiller

Brass
Registered
Joined
Apr 21, 2015
Messages
891
Likes
681
#29
I had my first such contact this week, but it really confused me because I knew I had done a dry run to make sure my full cut could be made without the carriage or anything on it running into the chuck. But something was definitely hitting. The fact that it was but I couldn't yet figure out what it was threw me off and made it harder to remember where the power switch and carriage feed lever were. Turns out I ran into the top of the saddle with the exterior-clamping jaws extended just far enough to reach. During my dry run I must have only spun the chuck before the carriage was over that far. Lesson learned, and there's a small scar to remind me. I'm glad this came without a hard collision or anything more than hardened steel jaws gradually scraping against an inclined cast iron surface.
 
D

Deleted member 473

Guest - Please Register!
Guest - Please Register!
#30
Amazing the damage a harden chuck jaw can do to cast iron parts of an lathe! :eek:

Chewed up compound slides! Ruts on the saddle and bed ways. I've seen them all, and even caused a few myself over the years.:grin:
 
[6]
[5] [7]
Top