• This site uses cookies. By continuing to use this site, you are agreeing to our use of cookies. Learn more.
  • PLEASE: Read the FORUM RULES BEFORE registering!

Goofs & Blunders You Should Avoid.

David S

Active User
H-M Supporter-Premium
#1
Forget my previous smart ass thread and lets see if we can contribute to the OP's original intent.

I do a lot of machining with small drill bits, cutters etc on my drill / mill.

When chucking up a very small diameter drill bit in a 13 mm three jaw chuck it is very easy to get the chuck to tighten down on the bit when it is between just two jaws and not centered among the three.

Turning on the press without first doing a manual sweep can break the bit or damage the work piece.

Always rotate the chuck after tightening by hand to check clearance.

David
 

T Bredehoft

Active User
H-M Supporter-Premium
#2
I've found that seating the back end of the drill bit in the back of the chuck makes centering the drill bit a little easier. Of course, if the drill is shorter than the depth of the chuck this doesn't work.

In the spirit of blunder. I have had the following experience. I needed to drill two .040 holes in a piece of aluminum, 3/16 thick. After breaking three or four drills I realized that the hand feed on my mill was not sensitive enough for me to feel when the bit was in aluminum, and i'd jam it into the material before slowing the feed. Talk about ham handed.
 

Wreck™Wreck

Active User
H-M Supporter-Premium
#3
I am game, made a few errors over the years.
Do not leave the drawbar wrench on the drawbar and then turn the spindle on with a Bridgeport type mill. This I have done in the past, I am short in stature however and no harm was done.

Turning the spindle on when it is holding an indicator is not recommended.
The last few years I have been programming CNC lathes, rapid moves go from the current position to the start position in a hurry, I have managed to break 2 parting tools so far, I have no problem with parting operations I do seem to bugger the rapid moves however.
 
Last edited:

Ulma Doctor

Infinitely Curious
Active Member
#4
don't leave the handle for your shop press in the jack, it'll poke your eye out- i had to explain that to a new work trainee, because i almost poked my eye with the handle he left in the jack.
don't mix synthetic grease with non-synthetic grease, you'll replace bearings soon after. i repair machines that are routinely ruined by operators not knowing that.
don't ever think that you know enough to not take advise.
 

brino

Active User
H-M Supporter-Premium
#6
Yesterday I was wondering what was wrong with my drill operation, it just wasn't working right.......and then realized the bit was spinning backward!
Some years ago I had installed a reverse switch on my drill press.....don't exactly remember why I needed it.
Apparently I had managed to toggle the rocker switch when I moved the drill press around the shop last week.

-brino
 

Reeltor

Active User
Active Member
#8
When its -40* don't lock your keys into your vehicle, always have a spare key in your wallet...in case you do.
It doesn't have to be -40* F for it to be a problem locking your keys in the vehicle. I like the keypad on the driver's door to unlock 1 or all doors. Years ago I had a client lock the doors with the engine running. Next car I bought and all since have the keypad.
 

astjp2

Active User
Active Member
#9
It doesn't have to be -40* F for it to be a problem locking your keys in the vehicle. I like the keypad on the driver's door to unlock 1 or all doors. Years ago I had a client lock the doors with the engine running. Next car I bought and all since have the keypad.
Yeah, I can tell that you have not spent much time at -40 from your comment, batteries don't work to well for your keypad unless its heated, hell doors don't even close properly, windows don't roll down, and at -40, locking your keys in is a life threating event...
 

David S

Active User
H-M Supporter-Premium
#13
how about clearing swarf on the lathe. Never ever use ones hands to push, clear, untangle the swarf building up. Use a brush to push it away or perhaps smooth handled pliers to try and grab some. The idea is that you don't want the pliers to get caught and pull your hand into the works.

Best of all turn off machine and remove the swarf and build up.

David
 

epanzella

Active User
Active Member
#16
I was drilling a hole in a spinning piece with the tailstock. After checking that the quill was clear of the tooling in the QCTP I began drilling the hole It was a small deep hole so I was pecking and suddenly I heard a rubbing noise. A tool holder was rubbing the spinning chuck. Because I was going slow it barely left a mark but could have been a real crash. I turned out that although the quill was clear, there was a bolt sticking out the bottom f it that was out of view from above. It touched the tooling and It was pushing the whole carriage along with it.
 

Martin W

H-M Supporter - Premium Content
H-M Supporter-Premium
#17
On the weekend I was turning a flange on the face plate. I only had 1/8" clearance between the part and the ways. I made about 4 passes with a boring bar. Then I pulled the lever up to stop the lathe and I cranked the carriage out of the way to measure. The aluminum cover that protects the ways must have been sticking up some on the end and caught the still spinning piece and broke it right off.
Looks like a tig welding project this week end:(
Martin W


Sent from my iPad using Tapatalk
 

george wilson

Global Moderator
Staff member
H-M Supporter-Premium
#18
Did someone delete MY goof?

My Hardinge HLVH starts up at 3000 RPM in a half second or so. Forward and reverse are buttons down on the cabinet. To unscrew a collet, I had reversed the lathe. I started the lathe up without looking at it starting,and using a collet to hold the brass rod I was working on. For some reason my tool would not cut. Then,I found out I had left the lathe in reverse!! Give me a chance to learn. I have only been using that lathe since the late 80's!!
 

olcopper

H-M Supporter - Premium Content
H-M Supporter-Premium
#19
Don't ever p*** on an electric fence, no matter how many beers you've had and who dares you.
Never ever leave the chuck wrench in the chuck before turning it on
kill all the power to a machine before replacing collets. A Mr. Sajo taught me that one!
Insure you tighten the clamp bolts on a round column mill-drill--took me two 1/2" carbide end mills back to back to learn that one
And many more
olcopper
 

RJSakowski

H-M Supporter - Premium Content
H-M Supporter-Premium
#20
Not life threatening or even machining related but here's one to avoid. Years ago, I was into developing my own color slides. I was in the process of developing the slides from a three week vacation out West and had loaded two rolls of film into a light tight cassette. I set it down to do and another task and, on returning, opened the cassette in bright light to see if I had loaded the film. Doh!:headache:
 

george wilson

Global Moderator
Staff member
H-M Supporter-Premium
#21
Back when I was in about the 2nd grade,I walked daily past a pasture of cows inside an electric fence. I must have leaned on that fence about 3 times,and got a BIGGGG jolt before I remembered to not lean on it while looking at the cows!!!

There was a bull in a pen across the road from the cows. He was very friendly to me(At least it seemed to be so while I was pulling up grass and feeding it to him. I never got INTO his pen!!!) One day the men were running about pretty alarmed because that VICIOUS BULL had gotten loose!!:)
 

MSD0

Active Member
Active Member
#22
Did someone delete MY goof?

My Hardinge HLVH starts up at 3000 RPM in a half second or so. Forward and reverse are buttons down on the cabinet. For some reason I had reversed the lathe. I started the lathe up without looking at it starting,and using a collet to hold the brass rod I was working on. For some reason my tool would not cut. Then,I found out I had left the lathe in reverse!! Give me a chance to learn. I have only been using that lathe since the late 80's!!
I've done the same thing so many times. A few times I ended up regrinding the tool and checking center before I figured it out.