Originally Posted by mactec54  Hi Guys
There is more to this key thing than most are aware of the key is not there just to hold the collet while you do it up
By removing the key in a R8 you leave a hole in the inside of the spindle ( in most) which can & will let metal chips & junk into the spindle bearings (on some) not good short life for the spindle bearings at $300 a set |
That is a valid point.
Originally Posted by mactec54 The key is there also to hold the collet from turning when you undo it if you get a tight thread I would like to see the mess you make of the collet/drawbar etc trying to get it out without a key |
I guess a little finesse is required. I'm not going to say it's impossible to screw something up, I'll only say I've never had a problem.
Originally Posted by mactec54 What would a manufacture go to the trouble to put a key in a spindle if you don't need it
may be Geof has the answer 20 years without a key???? |
I think he will be ok.
Originally Posted by mactec54 Machining centre's have key's some have ( 1 ) some have ( 2 ) to locate the tool holder
& to stop it from being able to turn in the spindle while cutting |
We're probably talking about a 2hp machine, and as you know, the spindle taper is what is holding the tool, otherwise the taper contact patch would not be so critical.
Originally Posted by mactec54 Another reason a key is there is so you put your collet/toolholder always in the same location in the spindle if your collet or toolholder get damaged or a chip gets on it there will only be damage in the spindle or collet/ toolholder in one place without a key you will get damage were ever the collet or toolholder is placed in the spindle it does not take long for a spindle to be of no use once it is damaged like this |
I have yet to see a R8 automatic tool changer, hence the operator input upon manual tool changes, I think you learn to keep precision surfaces clean and well kept on the fist day of your apprentiship, trade schooling, or on the job training, no?
Originally Posted by mactec54 I was at one time regrinding spindles 4 to 6 a week because of this kind of damage mostly because people new better than the manufactures & removed the key |
I rebuilt spindles for 9 years, I saw some of the dumbest mistakes ever made, some of them, I couldn't imagine watching happen. As much as I would not encourage removing the locating key from a R8 spindle, it's not the end of the world.
I have 2 knee mills without the key, bought them that way, never worried about it. They are both in use every day, one for 2 years, the other for 5 years, no problems with the spindles.
MC