Flying chuck key... worth preventing?

[RTP_Burnsville]

"I like the chuck key operated switch idea but it wouldnt work for alot of people. A lot of 3 jaw chucks and 4 jaw chucks use different size wrenches and a lot of people have two wrenches for their 4 jaw chuck. "

Sure it would.... You would just have to use two switches wired in series. That way if either of the chuck keys were not in it's place the machine would not start.

[hutchison]

machines should come ready fitted with an interlock switch (simple cam roller/plunger) fitted to the headstock, lift the chuck gaurd up and it kills the power etc, or rather the chuck wont spin with a chuck key in, and you'll not get a chuck key in with the gaurd down, there that ought to do it ! :-D .
I've not had the pleasure of using a brand new machine straight from the showroom etc if only! but i'm sure they would come interlocked chuck gaurd.
needless to say leaving the chuck key in is THE cardinal sin in the machine shop/toolroom to be drummed into the apprentice! and a spring is also a grand idea and we employed them aswell. but the interlock should be in place in the gaurd.

[TroyO]

Heh... there's a chuck guard?

Mine didn't come with anything like that, although it's a grand idea! I have a vac form machine, so I could make up something for that pretty easily.

It's a Harbor Freight 8x12 (Equivalent to a Lathemaster 8x14).

[sp4i6]

a flying chuck can kill you. if you don't take it out, you're taking your life into your hands. however, the first time it hits you hard in the nuts, you'll learn your lesson for life

[TroyO]

Hehe... yep, it does seem to happen that way. The worst injury I have ever taken in the shop was touching a table saw blade before it stopped. (Nice little chunk of thumb, but no hospital trip.)

I had read that florescent lights were a bad idea in the shop and learned first hand that a blade moving at 60 RPM looks like it's at a dead stop with florescent lighting.

I still haven't replaced the lighting, but now I give a count of 10 after I *think* everything has stopped before I touch the "hurty bit" of any machine.

[dertsap]

Originally Posted by TroyO a blade moving at 60 RPM looks like it's at a dead stop with florescent lighting. .

had a similar thing happen with an endmill on a Matsurra that had a burnt light and a dead quite spindle , a guy crashed the machine and homed it in then got me over for help , i looked at the endmill and it didnt look quite right , so i reach to spin the tool holder to get a better look at it , turned out it was spinning at 8000rpm , the tool was spinning at that right rpm that made it look like it was stopped , luckly i grabbed the holder and not the cutter , not sure who jumped higher me or the guy behind me who crashed and left the $&&&^ spindle running

[ImanCarrot]

I never let go of the chuck key unless it's in the one place its meant to be. In fact, I've spent 5 minutes searching for the damn thing before realising I was holding it.

[andypugh]

Originally Posted by hutchison machines should come ready fitted with an interlock switch (simple cam roller/plunger) fitted to the headstock, lift the chuck gaurd up and it kills the power etc, or rather the chuck wont spin with a chuck key in, and you'll not get a chuck key in with the gaurd down,

My Lathe came with exactly that arrangement _and_ a spring-loaded collar on the chuck key.

I removed the spring collar. As somebody else said it is just too tedious opening and closing the chuck half a turn at a time. (The spring was strong enough that this was all that was possible one-handed, and you need the other hand to hold the work)

[TroyO]

The spring I found is a good balance, you can one hand it with light palm pressure while you regrip for one handed opening, but it pops out of you totally let it go.

I still want to do the interlocks, for a couple of things... chuck key, chuck guard (or one for both if I can work it out that way) plus a positionalble stop and for when the gear drive door is open. Plus whatever else I can dream up... really the wiring is dead easy.

It's on the list of a handful of other upgrades anyway... who knows when/if I'll ever get them all done, LOL.