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Jim Stabe
07-07-2009, 12:49 PM
I have a Kondia variable speed mill and did something stupid that tore up a rather large cutter and ruined the R8 collet I was holding it in. This act of stupidity also damaged the key inside the spindle that fits in the groove of the collet. How do I get at the key or pin or whatever it is to replace it?

Jim

pcarpenter
07-07-2009, 01:03 PM
Can't speak to the Kondia specifically, but this gets discussed a lot here with regard to the Bridgeport. The general concensus seems to be that it ought to just be removed. I think that one good argument for removing it is that in the event of a crash like the one you experienced, the indexing "stop" (its just a set screw with a dog point cut on the end in the case of the BP) can dig a groove in the collet ect which can then, in turn, damage the spindle bore.

I would encourage you to carefully inspect the spindle bore for damage...and then perhaps just remove the indexing pin. Clearly it doesn't stop a crash from spinning the collet. I have to believe that its purpose is to prevent an R-8 tool from turning until the drawbar has enough tension on the tool to hold it in place. I find that I end up holding the tool in place with the other hand while initially spinning up the drawbar anyway, so I am not sure if this is all that important.

This is just one person's opinion though...you will likely get others here.

Paul

Fasttrack
07-07-2009, 01:24 PM
I would encourage you to carefully inspect the spindle bore for damage...and then perhaps just remove the indexing pin. Clearly it doesn't stop a crash from spinning the collet. I have to believe that its purpose is to prevent an R-8 tool from turning until the drawbar has enough tension on the tool to hold it in place. I find that I end up holding the tool in place with the other hand while initially spinning up the drawbar anyway, so I am not sure if this is all that important.

Paul

I agree with Paul. I've run several different BPs, a Lagun and some other BP clones and they all had that key removed. I suspect, as Paul says, that the key is to make tightening the collet easier. Sometimes, in shops that have a lot of traffic through them, the drawbar threads will get real dirty or damaged. Then having a key would be nice, as holding the collet in place with your hand may not be enough to prevent it from spinning. That being said, the correct way to deal with this problem isn't to force the drawbar, anyway. Ideally, one would remove the drawbar and clean up the threads and makes sure the collet threads were ok as well... :)

Quetico Bob
07-07-2009, 01:37 PM
Agree with both Paul and FT, mine was spun before I got it but there is still a little nub left. I just stick my finger in the bore to locate it, insert the collet and gently rotate while pushing up. You will feel whatís left of it to align. Tighten draw with other hand while maintaining up pressure. But as Paul said, inspect! Make sure whatís left isnít smeared all over the place. Was going to take mine out completely, but seems like a lot of work.

Cheers, Bob

Mcruff
07-07-2009, 06:12 PM
On the Klondia's I have seen just bring the quill down about 2" and then look on the back of the quill for a hole, it will have a set screw with allen head or screw driver slot, remove it and then the key below it will come out. On most mills the key can't harm the bore in this area as it is already cleared a little anyway. I just recently replaced mine on my Kent, took about 10 minutes. I personally use them and think that not having one in there is a pain in the butt. I have been running mils for 28 years and can't believe how many people tear them up and then are to lazy to fix them, they learn to work around something that makes thing so much simpler and easier.

tattoomike68
07-07-2009, 06:25 PM
pull that dumb key its worthless.

The first thing when you get a new mill is pull that setscrew/key and throw it right in the trash. Iv worked at many shops and on many mills and that key/screw is gone or soon to be gone..

If you need drive dogs get a mill with a 30,40 or 50 taper. the key in a R8,, its a joke and a bad idea from the start.

R8 collets suck ass for milling, buy endmillholders, collets are ok for drilling,,, kind of ok anyway. I find a good chuck bites them better then a collet.

juergenwt
07-07-2009, 07:15 PM
If you take out the key (Dog point set screw) and are using a left hand cutting tool it could spin loose and do major damage to your spindle. Keep it in place.

Jim Stabe
07-07-2009, 09:48 PM
On the Klondia's I have seen just bring the quill down about 2" and then look on the back of the quill for a hole, it will have a set screw with allen head or screw driver slot, remove it and then the key below it will come out. On most mills the key can't harm the bore in this area as it is already cleared a little anyway. I just recently replaced mine on my Kent, took about 10 minutes. I personally use them and think that not having one in there is a pain in the butt. I have been running mils for 28 years and can't believe how many people tear them up and then are to lazy to fix them, they learn to work around something that makes thing so much simpler and easier.
Got the set screw out, it was a real short one. I can still feel the remains of the key inside the spindle bore but I'm not sure how to get it out. I assume it comes out the same direction the set screw came out. I would like to replace it if I don't have to take the whole machine apart. Any ideas?

Jim

BadDog
07-07-2009, 10:50 PM
Look for another screw. The top one is a set screw to lock the dog point...

Walter
07-07-2009, 11:06 PM
I have to agree with the lose the key route, have no key in my Induma and love it. do have a key in the second mill and find it to be a pain in the butt.

Carld
07-07-2009, 11:57 PM
Leave the key out and if you think there is something in the bore use a die grinder to carefully remove anything sticking into the bore.

A collet will not back out if run in reverse as one poster said. I have never seen a collet back out or loosen when run in reverse without the key in the bore.

Most the mills that use R8 collets end up without the key and they never have any problem without the key.

Jim Stabe
07-08-2009, 12:09 AM
Look for another screw. The top one is a set screw to lock the dog point...
Which way does the dog point come out - can I drive it into the spindle bore or does it have to come out toward the outside? There is no allen socket or screwdriver slot under where the set screw was.

Jim

tattoomike68
07-08-2009, 12:50 AM
Its a right hand screw and a second get them out and give it a fling.