Goofs & Blunders You Should Avoid.

[kyjim1960]

Some task seem so routine and muldane, it is difficult to understand how or why they are often overlooked. A few years ago I purchased a used milling machine in excellant condition, except the spindle lock (or what I deducted USED to be a spindle lock) cast iron housing was busted all to hell and the internals gone or missing. I specifically remembered saying to myself, "what sort of dumbass would bust-out a spindle lock and how in the hell did he do it"? This is an excellant feature to use while tightening tool holders or collets, instead of the cumbersome boxend wrench on the spindile above the machine. So I set out with my JB Weld and repaired the housing, made a mock-up of the internals out of wood before turning the finished product out of steel on my lathe, monkied around with a few different springs, then after consideralble time, hand ground and blended the repaired casting, then bought some matching paint and you could never tell it was ever repaired!

About the second time I used the machine I forgot the spindle lock was engaged and turned the machine on and...you guessed it! I busted the spindle lock housing all to hell!! I was so mad I redid the JB Weld repair, (not as pretty as the first repair job) and perminantly adhered a postie note just below the on/off swithch stating: UNLOCK SPINDLE B-4 TURNING ON Needless to say, I quickly figured out how someone broke the spindle lock housing all to hell!!

 

[rwdenney]

That’s an awesome story. As soon as we think we have a bead in things, the machining gods will humble us.

Rick “been there done that” Denney

 

[gjmontll]

It's a good idea that Little Machine Shop includes an electrical cut-out on its "Deluxe High Torque Mini Mill" (model 4190)'s spindle lock. (Note that this is only on the "Deluxe" model. )
Rather annoying that it cuts off the power and that you needs both hands... right hand to unlock the spindle then left hand to reach around onto the left side to push the Power On button. Previously, I had a standard HF Mini-mill, with the LMS belt drive enhancement. I could stall the mill by grabbing the spindle. LMS isn't exaggerating when they call the 4190 "High Torque." This one you don't stall with a bare hand! I wonder what would happen if the interlock wasn't there, but my guess: probably fry the electronics.

 

[ChazzC]

It's a good idea that Little Machine Shop includes an electrical cut-out on its "Deluxe High Torque Mini Mill" (model 4190)'s spindle lock. (Note that this is only on the "Deluxe" model. )
Rather annoying that it cuts off the power and that you needs both hands... right hand to unlock the spindle then left hand to reach around onto the left side to push the Power On button. Previously, I had a standard HF Mini-mill, with the LMS belt drive enhancement. I could stall the mill by grabbing the spindle. LMS isn't exaggerating when they call the 4190 "High Torque." This one you don't stall with a bare hand! I wonder what would happen if the interlock wasn't there, but my guess: probably fry the electronics.

I added a Priest Tools spindle lock plate to my LMS 3990 Mini-Mill (which has the same drive system as the 4190) years ago (not the interlock one, just a plate with a hole that lets you make tool changes with both hands). Even with safety yellow tape on the handle of the lock pin, I still occasionally forget and push the power button without removing the pin: drive goes into fault immediately.

I’m curious as to why LMS didn’t have SIEG copy the Priest Tools interlock spindle lock as it doesn't require two hands to reset the system. Makes me re-think my money-saving decision and get the interlock version while they're still available.

 

[ChazzC]

I added a Priest Tools spindle lock plate to my LMS 3990 Mini-Mill (which has the same drive system as the 4190) years ago (not the interlock one, just a plate with a hole that lets you make tool changes with both hands). Even with safety yellow tape on the handle of the lock pin, I still occasionally forget and push the power button without removing the pin: drive goes into fault immediately.

I’m curious as to why LMS didn’t have SIEG copy the Priest Tools interlock spindle lock as it doesn't require two hands to reset the system. Makes me re-think my money-saving decision and get the interlock version while they're still available.

gjmontll said:
It's a good idea that Little Machine Shop includes an electrical cut-out on its "Deluxe High Torque Mini Mill" (model 4190)'s spindle lock. (Note that this is only on the "Deluxe" model. )
Rather annoying that it cuts off the power and that you needs both hands... right hand to unlock the spindle then left hand to reach around onto the left side to push the Power On button. Previously, I had a standard HF Mini-mill, with the LMS belt drive enhancement. I could stall the mill by grabbing the spindle. LMS isn't exaggerating when they call the 4190 "High Torque." This one you don't stall with a bare hand! I wonder what would happen if the interlock wasn't there, but my guess: probably fry the electronics.
------------------------------
Looking at the photos of the LMS 4190 spindle lock I don't see why you'd need two hands: to disengage the lock (as they describe it), you would pull out the knob and rotate it so the magnet points up, then rotate the spindle until the pin drops it the hole; to "engage" the lock, just pull out the knob and rotate it back so the magnet points at the sensor. Basically the same as you do with the Priest Tools version, just built-in rather than an add-on. From the LMS 4190 Product Page/Photos:

 

[gjmontll]

Looking at the photos of the LMS 4190 spindle lock I don't see why you'd need two hands: to disengage the lock (as they describe it), you would pull out the knob and rotate it so the magnet points up, then rotate the spindle until the pin drops it the hole; to "engage" the lock, just pull out the knob and rotate it back so the magnet points at the sensor. Basically the same as you do with the Priest Tools version, just built-in rather than an add-on. From the LMS 4190 Product Page/Photos:

View attachment 442362

Chazz: When I said it takes two hands, it's because locking the spindle powers off the mill. So right hand disengages the spindle lock, but then one would normally use their left hand to push the power On button.
Greg

 

[vocatexas]

I've got a lathe with an L1 spindle. I bought it five years ago and I was told the chuck was stuck when I bought it. I'm planning on cleaning it up and getting it back into service this summer. A couple of weeks ago I decided to try to get the chuck off again, so I built a wrench and went to work. I fought it for most of a morning working the lock ring back and forth. Well, it finally broke loose when I had my longest breaker bar in the wrench and one foot against the chip pan. I fell backwards against another machine and landed in the floor on my left hip. I could hardly walk for several days and my leg turned maroon from hip to mid-calf. These darned machines will bite you if they can! I also learned I don't bounce like I did when I was in my forties!

Let's be careful out there!

 

[woodchucker]

I've got a lathe with an L1 spindle. I bought it five years ago and I was told the chuck was stuck when I bought it. I'm planning on cleaning it up and getting it back into service this summer. A couple of weeks ago I decided to try to get the chuck off again, so I built a wrench and went to work. I fought it for most of a morning working the lock ring back and forth. Well, it finally broke loose when I had my longest breaker bar in the wrench and one foot against the chip pan. I fell backwards against another machine and landed in the floor on my left hip. I could hardly walk for several days and my leg turned maroon from hip to mid-calf. These darned machines will bite you if they can! I also learned I don't bounce like I did when I was in my forties!

Let's be careful out there!

sorry about your injury. That will take a while for the blood and swelling to clear. Glad you got it off, was it rusted on, or just hard on?

 

[markba633csi]

pun?
LOL

 

[vocatexas]

No, I was surprised it wasn't rusted as hard as it was to get loose. The spindle nose looked like somebody had lightly oiled it when the chuck was last installed, but the oil had dried out. There were dark stains on the spindle nose. I guess the residue was what made the chuck stick.