Is this my fault or PSI's?

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My lathe is setup for drilling the way I was told to set it up on here (Search the thread if you like) with the pen jaws in the headstock and the drill chuck in the tailstock. I could mount the drill chuck in the taper on the headstock, but since the jaws screw onto the 1"8tpi threads of the headstock, there's NO WAY they could be mounted down there.

But I'm glad you've all decided you had me figured out.

As for what I was doing at the time...I really don't remember. It happened quickly, and it was over in about one second. However, there is every possibility that I was backing the bit out at the time, and it bit into the blank while I was backing it out, which would account for it coming loose from the taper. The bit definitely snapped before it hit the ground, because the broken piece stayed on my bench after it hit the pegboard, while the chuck with the remaining piece ended up on the floor.
No, we don't have you figured out, far from it! It's just that the way your explanation of what happened didn't make any sense and we were trying to figure out what happened so we could possibly help you from kaming another possibly dangerous blunder!

But if you want to post something like this then get all defensive, that's your business, I'll keep that in mind the next time you post something like... "my tailstock fell off the lathe, is it the lathes fault or mine!"
 
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I drilled on the lathe for the first time the other night and was timid about it as it was the first time. I was drilling a Zen. I didn't like backing the bit out as it seemed to take some material (more dust than ribbons) as I was backing out. I was thinking it may be reaming the hole somewhat. I just stopped everything, moved the tail stock in a little, locked everything down and went in deeper. It worked good. I'm not sure if I'll do it again as I have a PH Vise and it works amazingly on my DP. I just didn't want to move my DP table down to allow for the longer Zen blank.
 
I'm guessing!!!!!!!!!

But I have seen a shop teacher set up the drillbit on the headstock and the piece to be drilled on the tail. I suspect that was the setup here.

I can certainly imagine that causing a chuck to possibly be pulled loose after drilling. When I bought my Jacobs chuck, I made sure the Morse taper mount was the end-drilled version, and I made a drawbar for it with 1/4-20 threaded rod. I use a small washer and star nut to tighten it against the handwheel. Maybe overkill, but I also cut a small piece of aluminum tubing I had to cover the allthread so it would not scratch the inside of the headstock spindle when inserted and removed.
 
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Were you holding onto the drill chuck? I drill the same way you do (chuck holding blank in headstock, Jacobs chuck holding drill bit in tailstock) and I have to hold the chuck to make sure it doesn't come loose, especially when retracting the tailstock...
 
I was drilling some ebony a minute ago, and my brand new 10mm Gorilla Grind drill bit snapped in half, the drill chuck flew out of my lathe across the shop, which of course ripped my blank in half also.

I've never had a drill bit break on me...especially one this thick! Is this something that I did wrong, or is this a shoddy part from PSI? I'll be returning it either way, but it sets me back a bit which is disappointing :( Does HF carry 10mm bits?

Ok, so I'm having issues with a couple of my tools...I'm sure it's probably operator error since I'm fairly new to this, but asking questions is how you learn :)

My band saw: Brand new Skil from the hardware store. When I cut, I set up the fence to the right diameter, and use the sled to push the blank through. However, as I cut, the blade pulls to the right (Away from the fence, towards the slide and my hand). It pulls farther faster if I try to push the blank through too quickly. It's actually pulled far enough to the right that it's nicked the table the blade goes through! Also I notice that on the last few blanks I've done, the blade binds very quickly with any pressure. I've cut less than 20 cuts on this saw! This is an annoyance and keeps me from cutting straight lines.

And onto the big problem: My lathe. I think that the HS and TS might be out of alignment...but I don't know how to properly diagnose or fix this problem. I've had a couple problems drilling (See Penturning forum for my 10mm bit that snapped in half) If I slide the tailstock away and spin the HS by hand, I can see visible wobble in the mandrel...I would have originally thought maybe the mandrel was just bent, but I take the mandrel assembly out of the lathe to use the pen jaw and drill chuck, so I'm not sure what's causing these issues.

Hopefully some of you smarter guys can help me figure this out!

The above 2 quotes pretty well sums up the problem. You have the tools, but apparently no or very little training with how to use the tools. All tools come with a instruction booklet, it tells you how to turn the tool on and turn it off. The rest of the booklet is wasted space filled with elementary information and few safety issues.

My advice is find a local turning or woodworking club, join it and ATTEND the meetings. Try to find a mentor that is experienced, not some other new lathe jockey that started last week. You will save yourself a lot of time on the learning curve.
 
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I always shut off the lathe when backing out the drill bit. I also notice you're using a brad point bit. For really hard woods like ebony, try a good standard point bit. If the lathe is spinning when you back out the bit, I have heard of exactly this type of thing happening.
John
 
It is definitely not normal to break a bit that large no matter what the brand. How fast was the lathe turning? I drill as slow as my lathe will go and keep my hand on the drill chuck so I can feel if it's starting to bind or come out of the taper. If it does I turn it off and remove it by hand. I have found when drilling on the lathe you have to clear the wood chips more often. I'm entirely a self taught I read as much as I can, get what gear I can/need and dive in. When things go boom I check to see if anything is missing, try to find out what happened,(details can be fuzzy when all you remember is diving under the bench because something sailed past your ear.) and learn from it. Hope all this rambling helps, My money is on a bad drill bit. However if the drill chuck does start to spin keep as much of it as possible inside the taper.
 
I wasn't putting my hand on the chuck...which I now realize is a great idea! Every now and then the bit will bind in the blank and start to spin the chuck...but using my hand I can feel it before that happens now!

I have to Live centers, and I stuck them in the head and tail today to see how off I am. They don't quite come point to point, but it's just a hair difference. The very tips barely go past each other...What I did notice, is when the headstock spins (by hand), there is a very very slight wobble to it. As in, the tip of the center in the headstock makes little tiny circles instead of spinning in place. It's easier to see when I put a mandrel in, because the motion gets bigger further away from the headstock, but I chalked it up to having a slightly bent mandrel, and replaced the mandrel rod. I never even thought to recheck it with the new rod on there!

So that explains why the bits bind on occasion...although I'm not convinced that that's the only reason for the tailstock to go flying the other day. I did check all my tapers to make sure they were clean. There was a little piece of sawdust here and there but nothing major...they're spotless now!
 
I wasn't putting my hand on the chuck...which I now realize is a great idea! Every now and then the bit will bind in the blank and start to spin the chuck...but using my hand I can feel it before that happens now!

I have to Live centers, and I stuck them in the head and tail today to see how off I am. They don't quite come point to point, but it's just a hair difference. The very tips barely go past each other...What I did notice, is when the headstock spins (by hand), there is a very very slight wobble to it. As in, the tip of the center in the headstock makes little tiny circles instead of spinning in place. It's easier to see when I put a mandrel in, because the motion gets bigger further away from the headstock, but I chalked it up to having a slightly bent mandrel, and replaced the mandrel rod. I never even thought to recheck it with the new rod on there!

So that explains why the bits bind on occasion...although I'm not convinced that that's the only reason for the tailstock to go flying the other day. I did check all my tapers to make sure they were clean. There was a little piece of sawdust here and there but nothing major...they're spotless now!

My friend The drill chuck, when properly seated in the taper will not "bind in the blank and start to spin the chuck" The quill on your lathe is probably self ejecting therefore it must be advanced far enough to clear the stop before the drill chuck is inserted.
 
I was drilling some ebony a minute ago, and my brand new 10mm Gorilla Grind drill bit snapped in half, the drill chuck flew out of my lathe across the shop, which of course ripped my blank in half also.

I've never had a drill bit break on me...especially one this thick! Is this something that I did wrong, or is this a shoddy part from PSI? I'll be returning it either way, but it sets me back a bit which is disappointing :( Does HF carry 10mm bits?

IMNSHO This is a textbook case of operator error.

Tim
 
I wasn't putting my hand on the chuck...which I now realize is a great idea! Every now and then the bit will bind in the blank and start to spin the chuck...but using my hand I can feel it before that happens now!

I have to Live centers, and I stuck them in the head and tail today to see how off I am. They don't quite come point to point, but it's just a hair difference. The very tips barely go past each other...What I did notice, is when the headstock spins (by hand), there is a very very slight wobble to it. As in, the tip of the center in the headstock makes little tiny circles instead of spinning in place. It's easier to see when I put a mandrel in, because the motion gets bigger further away from the headstock, but I chalked it up to having a slightly bent mandrel, and replaced the mandrel rod. I never even thought to recheck it with the new rod on there!

So that explains why the bits bind on occasion...although I'm not convinced that that's the only reason for the tailstock to go flying the other day. I did check all my tapers to make sure they were clean. There was a little piece of sawdust here and there but nothing major...they're spotless now!

My friend The drill chuck, when properly seated in the taper will not "bind in the blank and start to spin the chuck" The quill on your lathe is probably self ejecting therefore it must be advanced far enough to clear the stop before the drill chuck is inserted.

Sure it will. Unless you weld it in there or use a drawbar...
 
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