Thread: Piper Tapping Chuck

This is a superseded Piper chuck. Stuart asked whether I would dismantle it and post some photos.

Could not be more simple. The spindle has two drive dogs in the form of a square pressed in dowel. These dogs engage a pair of lugs inside the housing, providing drive when cutting a thread . When down feed is removed, the housing is raised up disengaging the drive lugs and the dogs, in turn, engage the gear on the spindle which, through the planetary gear assembly, reverses the spindle's rotation.

The red stuff is Timken grease.

BT

great photos. how do you set the depth ofof the thread

Thanks BT,
I always struggle with planetary gears, are the rpms the same in reverse?

azzrock, I assume you can set the depth with the quill depthstop. Although all the machine tapping I have done was through hole and mostly done free hand.

Stuart

I have not tried to use it to tap a blind hole to a fixed depth. From what I have read, you'd drill the hole over length and tap to the required depth. With the Piper, you could not use the quill stop because the chuck only reverses when the body of the chuck is moved upwards, disengaging the drive lugs. The reverse gear ratio is 2:1.

I had made a short video to show how it functions but for some reason I'm unable to upload it.

BT

Originally Posted by Anorak Bob

With the Piper, you could not use the quill stop because the chuck only reverses when the body of the chuck is moved upwards, disengaging the drive lugs.

But once the quill hits it's stop the tap would continue feeding until the clutch disengaged, then you let go of the quill feed and the reverse clutch engages. Although I'm not sure I would try this with a dog clutch in a blind hole as it would be disengaging and reengaging at maximum torque(even if it is only a 65% thread). The disengaging wouldn't to the clutch any good, the reengaging wouldn't do the tap any good.

Stuart

Here is Bob's chuck in action on the borer


https://www.youtube.com/watch?v=ucMHk-wJdbQ

Originally Posted by .RC.

Here is Bob's chuck in action on the borer


https://www.youtube.com/watch?v=ucMHk-wJdbQ

Nice action clip. If anyone will use it RC , it will be you.

That rubber "gasket" was only there for protection so the PVC sleeve didn't mark the steel in transit.

BT

Originally Posted by Anorak Bob

This is a superseded Piper chuck. Stuart asked whether I would dismantle it and post some photos.

Could not be more simple. The spindle has two drive dogs in the form of a square pressed in dowel. These dogs engage a pair of lugs inside the housing, providing drive when cutting a thread . When down feed is removed, the housing is raised up disengaging the drive lugs and the dogs, in turn, engage the gear on the spindle which, through the planetary gear assembly, reverses the spindle's rotation.

The red stuff is Timken grease.

BT

Caint see no photos ?

Originally Posted by YBAF

Caint see no photos ?

Here you go: Piper Tapping Chuck