I did not want to hijack Shop Dad's thread, but I mentioned a chuck being a scroll chuck and he did not understand the reference, so I am posting this in a separate thread in the hope others can find this in future searches.
The chucks commonly used in modern wood working lathes move the jaws in or out by means of a scroll shaped tooth machined into the chuck mechanism.
The scroll is rotated by either a hex key, two tommy bars, or in the Talon by a large key which looks like a big drill chuck key.
To illustrate, I removed the jaws on a Talon chuck. The concept will be similar on other scroll chucks.
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Each jaw has teeth which match the scroll pattern. Since it is a scroll the location of the teeth is DIFFERENT for each jaw. This is why the jaws have identity numbers stamped on the end of the jaw mounting block. I did not take a picture, since they are faint and would not likely show up in the picture.
The #1 jaw is stamped on the body. The jaw numbering goes anti-clockwise on my Talon chuck.
#2 and #4 jaws positions may be used for the jaw which contains a pin to prevent opening the jaws too far.
Despite my Talon chuck having a little pin on #2 jaw to prevent opening too far, I thought the chuck was stuck and continued to open the jaws, and then they fell out.
At the time I did not appreciate the jaws having identity numbers, so I spent a decent amount of time figuring out which jaw went in which position.
Only afterwards did I realize the numbering. :bangin:
To put the jaws back, the scroll is rotated so the first groove is about to be exposed in the #1 jaw opening. Then jaw #1 is put in place, slightly rotate, then #2 etc.
Since I mangled the pin on this jaw set, I now have to pay attention to the jaw position to ensure I do not open too far that the chuck will not hold the wood, and to avoid the jaws falling out again.
The jaw blocks are normally kept in the chuck. The actual jaw sets are screwed into the jaw blocks by one or two hex headed screws.
So when we talk about replacing jaws being a pain, it is the time to get the hex key (in my case a drawer in my lathe stand), and then unscrew either 4 screws or 8 screws (depending on the jaw model) and then replace with the other jaws and re-tighten 4 or 8 screws.
5 - 10 minutes, but we all hate doing this. :thumbdown:
The chucks commonly used in modern wood working lathes move the jaws in or out by means of a scroll shaped tooth machined into the chuck mechanism.
The scroll is rotated by either a hex key, two tommy bars, or in the Talon by a large key which looks like a big drill chuck key.
To illustrate, I removed the jaws on a Talon chuck. The concept will be similar on other scroll chucks.
Each jaw has teeth which match the scroll pattern. Since it is a scroll the location of the teeth is DIFFERENT for each jaw. This is why the jaws have identity numbers stamped on the end of the jaw mounting block. I did not take a picture, since they are faint and would not likely show up in the picture.
The #1 jaw is stamped on the body. The jaw numbering goes anti-clockwise on my Talon chuck.
#2 and #4 jaws positions may be used for the jaw which contains a pin to prevent opening the jaws too far.
Despite my Talon chuck having a little pin on #2 jaw to prevent opening too far, I thought the chuck was stuck and continued to open the jaws, and then they fell out.
At the time I did not appreciate the jaws having identity numbers, so I spent a decent amount of time figuring out which jaw went in which position.
Only afterwards did I realize the numbering. :bangin:
To put the jaws back, the scroll is rotated so the first groove is about to be exposed in the #1 jaw opening. Then jaw #1 is put in place, slightly rotate, then #2 etc.
Since I mangled the pin on this jaw set, I now have to pay attention to the jaw position to ensure I do not open too far that the chuck will not hold the wood, and to avoid the jaws falling out again.
The jaw blocks are normally kept in the chuck. The actual jaw sets are screwed into the jaw blocks by one or two hex headed screws.
So when we talk about replacing jaws being a pain, it is the time to get the hex key (in my case a drawer in my lathe stand), and then unscrew either 4 screws or 8 screws (depending on the jaw model) and then replace with the other jaws and re-tighten 4 or 8 screws.
5 - 10 minutes, but we all hate doing this. :thumbdown:
