Frozen Jacobs Drill Chuck Repair - Disassembly, Cleaning, Inspection

heathicus · Post by **heathicus** » Sun Sep 13, 2009 1:06 pm

The jaws and holes were not numbered on mine either. Mine was an actual 3326, not a multicraft but I cant tell any difference.

Upon reassembly, I did not make sure to put the jaws back in the same holes, but I did make sure to keep the jaws in the same position relative to each other and the chuck has performed flawlessly.

mickyd · Post by **mickyd** » Sun Sep 13, 2009 1:54 pm

heathicus wrote:The jaws and holes were not numbered on mine either. Mine was an actual 3326, not a multicraft but I cant tell any difference.

Upon reassembly, I did not make sure to put the jaws back in the same holes, but I did make sure to keep the jaws in the same position relative to each other and the chuck has performed flawlessly.

Me being a stats guy, you stood a 1 in 6 chance, (16.7% probability) of assembling the 3 jaws into the correct 3 holes due purely to chance. Looks like you did it!! You lucky dog you. Next thing you know, your going to run into some once in a lifetime SWEET deal on a ShopSmith

a1gutterman · Post by **a1gutterman** » Sun Sep 13, 2009 3:30 pm

Wonderfully done, Mike! I have wondered, for many years, how to disassemble a drill chuck!

heathicus · Post by **heathicus** » Sun Sep 13, 2009 5:27 pm

mickyd wrote:Me being a stats guy, you stood a 1 in 6 chance, (16.7% probability) of assembling the 3 jaws into the correct 3 holes due purely to chance. Looks like you did it!!

I'm not a mathamagician, so can you explain the math? I was thinking I had a 1 in 3 chance. If I keep the jaws the same position relative to each other, there are only 3 possible positions. See attached crude diagrams.

Were you able to see any differences with the holes in the body or with the jaws that would require specific holes and jaws to be matched? I couldn't see anything like that on mine. The only difference was the threads or the jaws so they needed to be in the right order.

mickyd wrote:You lucky dog you. Next thing you know, your going to run into some once in a lifetime SWEET deal on a ShopSmith

mickyd · Post by **mickyd** » Sun Sep 13, 2009 5:53 pm

[quote="heathicus"]I'm not a mathamagician, so can you explain the math? I was thinking I had a 1 in 3 chance. If I keep the jaws the same position relative to each other, there are only 3 possible positions. See attached crude diagrams.

Were you able to see any differences with the holes in the body or with the jaws that would require specific holes and jaws to be matched? I couldn't see anything like that on mine. The only difference was the threads or the jaws so they needed to be in the right order.

]

Probability 101

Inference: "How many possible combinations are there of 3 things?"
Answer: 3 factorial = 3! = 3 x 2 x 1 = 6

Hole A, B, C
Jaw 1, 2, 3

so

A.....B.....C
1.....2.....3
1.....3.....2
2.....1.....3
2.....3.....1
3.....1.....2
3.....2.....1

You see now grasshopper?

iclark · Post by **iclark** » Sun Sep 13, 2009 6:36 pm

mickyd wrote:Probability 101

Inference: "How many possible combinations are there of 3 things?"
Answer: 3 factorial = 3! = 3 x 2 x 1 = 6

Hole A, B, C
Jaw 1, 2, 3

so

A.....B.....C
1.....2.....3
1.....3.....2
2.....1.....3
2.....3.....1
3.....1.....2
3.....2.....1

You see now grasshopper?

um, Mike, I think you missed the constraint of the jaws being in the same (original) relative position.

that reduces the possibilities to:
A.....B.....C
1.....2.....3
3.....1.....2
2.....3.....1

Ivan

JPG · Post by **JPG** » Sun Sep 13, 2009 6:50 pm

iclark wrote:um, Mike, I think you missed the constraint of the jaws being in the same (original) relative position.

that reduces the possibilities to:
A.....B.....C
1.....2.....3
3.....1.....2
2.....3.....1

Ivan

AND since the holes ARE identical, the possibility of Ivan getting his assembled 'Properly' is 100% with his 'sequence/order restraint.

Mike's potential number of combinations are 2 since the holes ARE identical. IF he got it wrong, he only needed to reverse the position of two of them.
123 == 231 == 312
132 == 321 == 213
ABC .... ABC .... ABC

In fairness to Mike, he was acting on info that implied the holes were unique. Thanks for the peek at your info source. I found it quite different(good) from the jacobschuck site(more history/insight to real world dealing with the repair of the chucks).

wlhayesmfs · Post by **wlhayesmfs** » Sun Sep 13, 2009 7:42 pm

I just hope I don't need to take my apart, Math and I don't mix. I look at pictures.

wlhayesmfs · Post by **wlhayesmfs** » Sun Sep 13, 2009 7:44 pm

obviously I don't read before I send either:eek:

mickyd · Post by **mickyd** » Sun Sep 13, 2009 9:20 pm

iclark wrote:um, Mike, I think you missed the constraint of the jaws being in the same (original) relative position.

that reduces the possibilities to:
A.....B.....C
1.....2.....3
3.....1.....2
2.....3.....1

Ivan

what about

A.....B.....C
2.....1.....3
1.....3.....2
3.....2.....1