Is this supposed to come apart?

slap shot

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I was milling a lower today with my HB benchtop mill and i noticed the bit seemed to be going a little deeper than the previous pass and i hadn't touched it. Turns out the chuck slipped off the spindle. What holds these two pieces together? I was going to replace this with an R8 collett but so far this setup seemed to be working. Couple more pics, i'm confused.

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They come off...they can be switched out...held by friction...put it back on with a good whack from a rubber hammer...
 
It surprised me too the first time it happened to me on my drill press. [laugh]

Friction fitting it doesn't seem quite right, but I guess it works.
 
The chuck should have a screw holding it to the arbor. You see the hole in the end where the chuck would go (on the arbor)?? You have a screw loose/missing there.

Friction fittings are typically for MT arbors into drill presses, not mills. That looks like a R8 collet to hold the chuck assembly in the mill.
 
...and here I thought I was helping...[sad]


...didn't know a mill set up would be different...'course a mill is used to machine tight tolerances so why would it be a simple friction fitting...duh...
 
The chuck should have a screw holding it to the arbor. You see the hole in the end where the chuck would go (on the arbor)?? You have a screw loose/missing there.

Friction fittings are typically for MT arbors into drill presses, not mills. That looks like a R8 collet to hold the chuck assembly in the mill.

I'll go look around. Yes, the upper half is tapered and draws up into the housing. I just was surprised to see these 2 parts separated. Thanks
 
Yeah, good/decent mills (or those worth owning) would use the R8 collet to hold items. Depending on the collet set owned, you can put drill bits into them (the same size as the collet opening). Such as a 3/8" bit into a 3/8" collet. Since collets have more surface area holding the bit, it works really well.

Mills also, typically, use a draw bar to hold the collet in the spindle. This makes it so that it won't drop out with side-load on it (like you get when trying to use a drill press to mill).

slap shot, look for the dropped screw from the arbor. If you cannot locate one, take the collet to a good hardware store (like a True Value) and go through their selection until you find one that is the correct thread (if you don't have the tools to figure that out before hand). Maybe take the chuck with you too, so you can make sure you get the right length. Then use some blue Loktite on the screw so it won't vibrate out again.
 
...if I recall (and like on a hand drill chuck)...aren't they left-hand threads...NOT righty tighty lefty loosey?
 
...if I recall (and like on a hand drill chuck)...aren't they left-hand threads...NOT righty tighty lefty loosey?

I don't recall since I've not had to touch one in a long time. When I get a drill press, the arbor and chuck are assembled. It's usually outlined in the manual that comes with the machine (RTFM).

I just looked in the manual for my Porter Cable (floor stand) drill press. No mention of securing the chuck to the arbor with a screw. But, 99.995% of the time, you're not putting any side-load onto a drill chuck, so it shouldn't matter. If you are, you'll want the chuck secured with a screw (to the arbor). Otherwise, the side-loading of the chuck can/will break the friction hold on the parts and the chuck will drop.
 
ok, no screw holding together the 2 parts shown. You can kind of see in picture 2 there is a slight taper or shoulder even on the small end that goes into the chuck.

I'm pretty sure it's friction but now that i've removed the screw on top that holds the spindle in, i cant get that back in either. Wow, i really didn't want to take this apart. And i will probably go the collett route at this point as i have been meaning to.
 
ok, no screw holding together the 2 parts shown. I'm pretty sure it's friction but now that i've removed the screw on top that holds the spindle in, i cant get that back in either. Wow, i really didn't want to take this apart. And i will probably go the collett route at this point as i have been meaning to.

Did you align the groove in the collet with the spot on the spindle? You should be able to just turn the top nut/screw until it grabs the threads of the arbor.

Which mill do you have (assume you meant to type HF, not HB earlier)?

If you do have the small HF mill (smallest they sell) go over to Little Machine Shop and get the single piece draw bar for your mill. It will make things easier for you.
 
Did you align the groove in the collet with the spot on the spindle? You should be able to just turn the top nut/screw until it grabs the threads of the arbor.

Which mill do you have (assume you meant to type HF, not HB earlier)?

If you do have the small HF mill (smallest they sell) go over to Little Machine Shop and get the single piece draw bar for your mill. It will make things easier for you.

Yes, i meant harbor freight, and yes, i'm aligning the groove with the thing sticking out. Yeah its the tabletop one and i'll check that out. thanks
 
Yes, i meant harbor freight, and yes, i'm aligning the groove with the thing sticking out. Yeah its the tabletop one and i'll check that out. thanks

You have the stop bar in place to keep the spindle from moving? If the nut is too low on the stud (of the draw bar) you might not have enough extending to reach the arbor. You should be able to insert the arbor all the way in, and screw the draw bar into it.

You might just be having a 'blonde moment' with this... [laugh]
 
You have the stop bar in place to keep the spindle from moving? If the nut is too low on the stud (of the draw bar) you might not have enough extending to reach the arbor. You should be able to insert the arbor all the way in, and screw the draw bar into it.

You might just be having a 'blonde moment' with this... [laugh]

I wish, the spindle is clearly not going up far enough to reach the bolt that comes in from the top. I've inspected it from both top and bottom and i cant see anything. Very strange. I think if i have a bourbon with 2 ice cubes i might see it better. Maybe i just need a bigger hammer. lol
 
I wish, the spindle is clearly not going up far enough to reach the bolt that comes in from the top. I've inspected it from both top and bottom and i cant see anything. Very strange. I think if i have a bourbon with 2 ice cubes i might see it better. Maybe i just need a bigger hammer. lol

Ahhh, better living through alcohol. [smile]

With the draw bar loose, you should be able to push the arbor all the way up the spindle. The draw bar should get pushed up above it. If you don't have the groove in the arbor aligned properly, it won't go up correctly (or deep enough).

If it's still not working, it must be defective. I'll come down and transport it away for disposal for you. [laugh]
 
Got it...glad it is (almost) back together.

Slap Shot...don't forget the fastener holding the chuck secure might have left handed threads!

...and good luck!
 
its definitely back together, i was able to continue milling.

There are no threads to allow a screw to hold those 2 pieces together. You can see a hole in picture 3 but i cleaned it thoroughly, no threads. It is only on with friction as far as i can tell.
 
its definitely back together, i was able to continue milling.

There are no threads to allow a screw to hold those 2 pieces together. You can see a hole in picture 3 but i cleaned it thoroughly, no threads. It is only on with friction as far as i can tell.

You really should get a set of R8 collets for holding end mills. You can get them for pretty cheap, from good sources. Get a set in 1/16" increments (you don't need to go smaller) and you'll be fine. Most end mills have shanks that work with that increment. I think you can locate a set on either Amazon, LMS, or even ebray for under $75 (delivered if you have Amazon Prime).

Amazon set link: http://www.amazon.com/Steelex-M1079...&qid=1380925028&sr=8-1&keywords=r8+collet+set
 
You really should get a set of R8 collets for holding end mills. You can get them for pretty cheap, from good sources. Get a set in 1/16" increments (you don't need to go smaller) and you'll be fine. Most end mills have shanks that work with that increment. I think you can locate a set on either Amazon, LMS, or even ebray for under $75 (delivered if you have Amazon Prime).

Amazon set link: Steelex M1079 R-8 Collet Set - Amazon.com

Definitely doing this. thanks for the tip.
 
Definitely doing this. thanks for the tip.

As you already found out once (and been told by more of us) using a drill chuck to hold end mills is not a good idea. It's ok for short runs (an inch or so) but not for any length of time/cut.

If you want to get some good end mills for pretty cheap, I know of a place in Derry, NH that has both new, and used, bits for sale. Many of the used ones either can be sharpened, or were (still have the coating on them).

A milling machine will pretty much complete the set I need to do whatever I want. Well, other than getting an electric welder (MIG or TIG). I just want one with enough power to handle whatever I'll throw it's way.

BTW, when you're on LMS's site, check out the gas piston system for your mill. You'll get more travel on your Z axis that way. There are a lot of other things you can do to that mill to help it along too. Things like the motor fan replacement (to one that actually does some good). Or even changing the table to a larger one (giving you more travel on the X and Y axis. IMO, DRO's are rather important items too. Depending on what you're machining that is. They made finishing the 80% lowers much easier.
 
Got my collets in Thursday, Wow! these are great. Not only is it smoother when milling, i have lots more clearance. When going deep, no fear of touching the threaded loop where the buffer tube attaches.
 
View attachment 80791

I was milling a lower today with my HB benchtop mill and i noticed the bit seemed to be going a little deeper than the previous pass and i hadn't touched it. Turns out the chuck slipped off the spindle. What holds these two pieces together? I was going to replace this with an R8 collett but so far this setup seemed to be working. Couple more pics, i'm confused.

View attachment 80792View attachment 80793

Yes...normal machinist situation. Just tap it back into place with a plastic mallet.
 
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