How many end mills does it take to figure out you are cutting UHMW and not POM?

[mmcmdl]

You figure you have a 50-50 shot at it ………………...but you're wrong darn near 100% of the time .

 

[Ulma Doctor]

my very first experience with a Mill/Drill/Lathe was ruined because i tried climb millin' without knowing it

 

[mmcmdl]

New meaning to R&D, Reverse & Destroy?

Have you ever seen how a tabbed conveyor belt acts when started in reverse ? It ain't purdy ……………..especially after pulling that chain for 5 hrs . We used to tell the electricians to test rotation before starting the line , if not , they'll be the one's feeding the belt next time .

 

[mmcmdl]

My Enco mill in here at work has 1 switch which is a 2 speed , forward / reverse switch combined . Most of my night consists of removing broken bolts out of the extrusion dies . The dies are 15-5 or 17-4 SS up around 48RC and of course the bolts are grade 8s . I go from forward to reverse all night trying to pull the darn bolts out with left hand drills , carbide EMs , easy outs , etc . At 4 o'clock in the morning after 10 hours or so sometimes strange things happen to that forward / reverse switch ! It acts up for some reason .


That's my story and I'm stickin to it !

 

[homebrewed]

This talk of motors turning the wrong direction reminds me of something that happened at work. We had sent a small mechanical vacuum pump out to get it rebuilt, got it back, and re-installed in the tool, which was a type of vacuum etcher. Being the lab's jack-of-all-trades I was given the job of turning the system back on. When I did, I discovered the vacuum pump had turned into a compressor! The idiots who rebuilt the pump had reconnected the motor wires wrong.....so it was turning the wrong direction.

Fortunately I figured out what was going on before any of the seals in the tool (or vacuum pump) blew out. We never used that rebuild place again, that's for sure! A $1K rebuild came close to seriously damaging a $250K tool. Bad, bad.

 

[rock_breaker]

Have you ever seen how a tabbed conveyor belt acts when started in reverse ? It ain't purdy ……………..especially after pulling that chain for 5 hrs

Been around rock crushers quite a bit but I can't remember what a tabbed conveyors looks like. That sounds similar to plugged chutes with wet sand under a scalping screen in 0` weather.
Have a good day
Ray

 

[uncle harry]

New meaning to R&D, Reverse & Destroy?

For me it was ROUGH & DUMB (and I was actually the corp.manager of research and developement).

 

[Downunder Bob]

My first experience with wrong way motor, I was about 12 or 13 and very involved with model aeroplanes control line style. The motors I had were compression ignition type with a compression adjust screw on top of the cylinder head. One day starting the motor by flicking the propeller by hand, after a few flicks the motor started, but much to my surprise was running the wrong way.

One of the older fellows in the group explained that it could happen sometimes. It wasn't until many years later while studying engineering that I discovered how and why this could happen.

Again some years later replacing a 3 phase motor and yes, you got it, it ran the wrong way. the electrician explained how to swap over any two of the 3 phase wires and it went the right way.

 

[Dhal22]

Not uncommon for a radio control engine to run backwards, gas, nitro or diesel.

 

[Downunder Bob]

Yes any two stroke engine can run backwards. Big ships diesel engines don't have a gearbox, so to go backwards they stop the engine and restart it running backwards.