# Question re HF 7 x 10  Chuck



## Tinkershed (Nov 10, 2021)

Guys please forgive me if this question has been answered elsewhere. I recently revived my HF mini lathe to make a few parts and as it had been sitting for a while it needed  a little cleanup.  It hasn't been used a whole lot and is generally in good shape.  In my blissful ignorance I took the jaws out of the chuck as part of the cleanup and I did note that each jaw has a number so I wasn't worried about getting it back together UNTIL I tried to reassemble it 

I then discovered no trace of a number on the main part of the chuck.  maybe I'm looking at the wrong spot.   As you look at it in a position where the trade mark is readable, there is what looks like a number 1 immediately opposite.  There is no indication of a 2 or a 3.   There may be a convention (maybe  1 is opposite the trademark 2 is to the left an 3 to the right, but for all I know it could be something else.

Do you guys know how this thing should go back together?  I would really appreciate some ideas here.   Thanks in advance.


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## MrWhoopee (Nov 10, 2021)

As you rotate the scroll in the tightening direction, #1 will be the first to engage. Continue tightening and #2 will be the next to engage, and on to #3. Assuming the scroll is rotating clockwise, #2 will be the next slot in the clockwise direction.
Hope that's clear.


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## benmychree (Nov 10, 2021)

If you successfully reassemble it and it runs true and the jaws fit properly, it may be a good idea to stamp the body with the matching numbers.  Most chucks are so numbered.


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## Janderso (Nov 10, 2021)

So the slots aren’t specific to a given number?
I understand how to load in scroll sequence it’s just why bother stamping the body if it doesn’t matter?


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## benmychree (Nov 10, 2021)

Janderso said:


> So the slots aren’t specific to a given number?
> I understand how to load in scroll sequence it’s just why bother stamping the body if it doesn’t matter?


It seems that sometimes the jaws fit slots a bit differently than others, as I said, most chucks that I have worked with are numbered.


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## markba633csi (Nov 10, 2021)

I believe the really inexpensive chucks don't bother numbering the body, so you can start #1 on any of the three slots. However, you probably should try all 3 possible combinations and see if one is slightly more accurate than the others. I would.
-Mark


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## silence dogood (Nov 10, 2021)

Place all three jaws the long ways next to each other in line.  The teeth are all facing up with the triangle end pointing the same direction.   On jaw number 1, it's tooth is closes to the triangle end.  Start with that one.  Jaw no. 2  the space before the tooth is a little bigger, that's next.   Jaw no. 3 has the biggest space.  When you tighten the jaws and all three meet in the middle, you got it.  If not, start over,  you might had turn the scroll  too far.   This will work with the other three jaws that goes with your chuck.  This method should work with most self-centering scroll type chucks.


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## Tinkershed (Nov 10, 2021)

Thanks very much for the replies.  I will try in order all three positions and see how it works.   I really appreciate the responses.  I will report how it all turns out.


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## Canuck75 (Nov 11, 2021)

Another thing that is interesting is that the jaws don't care which slot they are in, just the order that they engage the scroll plate, as "silence dogood" says. So, when you have the order worked out, and temporarily marked a starting slot, try moving the set beginning at the next slot, and then the third, and keep track of how easy the jaws move. When you have the ideal "feel", stamp the jaws and chuck body accordingly. I have a German  NCK 4" 3-jaw that the inside jaws are actually mis-numbered - check the top row of jaws in the attached photo, you'll see the #2 and #3 have to be swapped. Had me scratching my head for while!


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## Tinkershed (Nov 11, 2021)

Canuck75 said:


> Another thing that is interesting is that the jaws don't care which slot they are in, just the order that they engage the scroll plate, as "silence dogood" says. So, when you have the order worked out, and temporarily marked a starting slot, try moving the set beginning at the next slot, and then the third, and keep track of how easy the jaws move. When you have the ideal "feel", stamp the jaws and chuck body accordingly. I have a German  NCK 4" 3-jaw that the inside jaws are actually mis-numbered - check the top row of jaws in the attached photo, you'll see the #2 and #3 have to be swapped. Had me scratching my head for while!


You absolutely solved the problem.  As soon as I reversed 2 and 3 it came up centered just fine.  Thanks to all.  I am working on a custom tool for a project and need the lathe to shorten a spacer.  This custom tool is the key to the whole project so thanks for the help!


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