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Is This Chuck Safe?

Posted: Sun Dec 13, 2009 2:31 am
by m.c.
Hi, I'm about to buy a wood lathe for stummel work but have some qualms about chuck safety. My understanding is that you mostly use a two-jaw chuck for stummels. But all I can find in my location are such stubby things instead of the long protruding jaws you pros use. My concern is about the length and breadth of the jaws. Do they offer adequate grip? Are these safe? Thank you for any suggestions that help save a dent or two in my face. :)

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Re: Is This Chuck Safe?

Posted: Sun Dec 13, 2009 10:02 am
by pipesmokerdude
First be careful with the wood lathe. The chuck you show, might work but there is not allot of contact with the work. Allot of us use a 4 jaw with 2 of the jaws removed.

Look here

http://briarpipetooling.com/index.php?o ... &Itemid=27

One can be made, I just got done with mine. If you have welder and can do some light milling, your set.

Re: Is This Chuck Safe?

Posted: Sun Dec 13, 2009 10:55 am
by m.c.
pipesmokerdude wrote:First be careful with the wood lathe. The chuck you show, might work but there is not allot of contact with the work. Allot of us use a 4 jaw with 2 of the jaws removed.

Look here

http://briarpipetooling.com/index.php?o ... &Itemid=27

One can be made, I just got done with mine. If you have welder and can do some light milling, your set.
Thanks. The contact area was right my concern. After some research, it suddenly clicked with me that a 4-jaw can be used without removing 2 jaws by clamping the block like this: (red is jaw; blue is block). Am I right?

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Re: Is This Chuck Safe?

Posted: Sun Dec 13, 2009 2:32 pm
by Sasquatch
Theoretically, that's right, assuming your chuck is large enough, and you have 4 independant jaws.

That arrangement will not let you "spin" a stummel around in order to do the shank, for example. You'd have to completely dissassemble and re-center.

Re: Is This Chuck Safe?

Posted: Sun Dec 13, 2009 4:33 pm
by SimeonTurner
It's definitely possible to use a 4 jaw chuck for turning your stummel/shank. Squatch is right, you do have to remove the pipe from the chuck for each part of the pipe, but it works fine, usually.

I currently use a Nova Precision Midi Chuck with a set of 50mm jaws (minus 2 of the 4 sides) for most of my lathe shaping. http://www.woodcraft.com/Product/208032 ... -Sets.aspx. I know other folks around here use Oneway chucks to the same effect.

I'm taking the earnings from my recent club pipe set and re-investing in a specialty pipe turning chuck (probably from Trent Rudat). The reason is that occasionally, when using 4 jaw chuck with 2 jaws like we are talking about above, I have had the block slip out in dramatic fashion, which obviously sucks. A lot. Having a set of flat jaws specifically made for pipe making will be really nice, if for no other reason than my own psychological health. LOL

Assuming you don't want to drop 500+ bucks on a specialty chuck, you should be fine with a 4 jaw-converted to 2 jaw. Just be sure you tighten it down hard each time. :)

Re: Is This Chuck Safe?

Posted: Tue Dec 15, 2009 7:11 am
by m.c.
Very helpful info, guys. So I think an independent-4-jaw will be my first choice now. Just what is the optimum RPM for drilling the bowl and airway? Too low and the bit may bite off chunks. Too high it may launch a briar grenade. What's the acceptable range?

Re: Is This Chuck Safe?

Posted: Tue Dec 15, 2009 10:07 am
by Leus
I do some stupid shenanigans when drilling pipes. I don't have a four jaws chuck, so I use a three jaws chuck, removing one jaw. I'm about to ask a friend that has a metal shop to make me a chuck like one I saw around here (I think it is Todd's design.)

The problem with my current setup is that vibration will sometimes produce a little misalignment that may set your piece loose and ruin it giving you a big scare in the process. That is because the jaws are too small and have little contact surface with the piece.

Re: Is This Chuck Safe?

Posted: Tue Dec 15, 2009 1:20 pm
by KurtHuhn
That chuck looks like machining some larger and grippier (is that word?) jaws would be rather easy. Or, modify the jaws there by attaching a larger gripping surface to their face. Assuming the chuck is inexpensive enough to begin with, it might be worth some reworking to make it useful.

Re: Is This Chuck Safe?

Posted: Wed Dec 16, 2009 8:07 am
by m.c.
Modification is beyond my reach and is not yet necessary since I don't have efficiency to worry about. So I will just try and find a regular 4-jaw with reasonabe contact areas and paste a Ronnie Coleman pic on the side of the lathe as a reminder of the jaw tightening ritual. :D