Power drawbar for mill

[fillister]

Hello, I built this over the last several weekends, it utilizes 1/2 guide rods and an 1.5 bore x 1" travel air cylinder with internal return spring and 3 air solenoids on a common manifold. It is controlled by a maintained push button for the down motion and a SPDT momentary spring return for the forward reverse rotary motion. The only real problem I ran into was that the down motion is so rapid it would dislodge the socket at the end of the travel limit. The simple solution was to open the existing socket keeper hole to a #7 drill and tap to a 1/4 20 for a set screw.

No more problems with a dislodged socket.

 

[pontiac428]

Looks substantial! Nicely done.

 

[MikeInOr]

Looks good! I would enjoy seeing a video of it in action if you are able to post one?

A needle valve usually does a good job of slowing down a pneumatic cylinder that moves too quick.

 

[pontiac428]

There is a video posted, in high-res! Look in and amongst the pictures.

 

[fillister]

Looks good! I would enjoy seeing a video of it in action if you are able to post one?

A needle valve usually does a good job of slowing down a pneumatic cylinder that moves to quick.

Unfortunately the video is sideways, I should have held it horizontally, thanks for the idea on the needle simple to implement.

Thanks

 

[fillister]

Looks substantial! Nicely done.

Thank you Pontiac, I appreciate the comment

 

[davidpbest]

@ahazi should see this.

 

[Shootymacshootface]

Not too shabby, outstanding actually.
Might I suggest an adjustable valve to control the airflow to the cylinder? It moves a bit too fast for me, may be problematic over time.

 

[MikeInOr]

Not having ever used a power draw bar; is it possible to have the impact wrench always connected to the draw bar even when the mill is running? Does the top of the draw bar go into the head when the quill is lowered?... I have never paid attention. It seems like my impact wrenches turn pretty freely when there isn't any pressure?... but also something that I have never really paid attention to. Just curious.

 

[ErichKeane]

Not having ever used a power draw bar; is it possible to have the impact wrench always connected to the draw bar even when the mill is running? Does the top of the draw bar go into the head when the quill is lowered?... I have never paid attention. It seems like my impact wrenches turn pretty freely when there isn't any pressure?... but also something that I have never really paid attention to. Just curious.

Yep, the top of the drawbar does move down with the quill, so it ends up being disconnected anyway.

I've definitely seen versions of this though that ONLY have the left/right control, but that can prematurely wear the impact since it isn't getting oil (which is often in the compressor supplied 'air' if you have an oiler).