CX601 Power Drawbar project

[lucsimoneau]

Hi all ... Happy Easter!

Ok, I'm looking into installing a pneumatic drawbar on my CX601 Craftex Milling machine.
I was considering a change of spindle for a used FM30F 3Hp BT-30 spindle but the price was just too expensive, considering I would also have to change out all my TTS tooling.
Maybe somewhere down the line but not today.

So I thought I'd start a new project on things that make working on the mill a bit of a pain. Starting with the tool changes.

Yesterday I was going thru some web pages and came across Adam Savage's latest post on his new PM-728V-T machine with a pneumatic drawbar.

Bingo, new project in the horizon, and after a few searches found this concept:

Have any of you installed this type of power drawbar on your machine using a butterfly air wrench?

Will be taking dimensions today to come up with a design but any thoughts would be great.
Thanks!

 

[Susquatch]

I don't need such a device. My drawbar is easily within reach even on my big Bridgeport Clone, and a ratchet style combination wrench works just fine. So I shouldn't really be commenting at all.

That said, I'd highly recommend Electric or Battery. In my opinion, compressed air is a total PIA - noisy, hissy, trip hazard hoses and gotta build pressure before use. I'm sure I can come up with more reasons to hate it. The day Dewalt introduced a 20V 1200ftlb impact gun was a very happy day in my shop!

The other thing is quick removal of the head. There are times you need to take the drawbar out. As designed, that thing would not be very convenient.

 

[John Conroy]

I did one anfew years ago.

Thread 'Power drawbar on my Bridgeport clone mill' https://canadianhobbymetalworkers.com/threads/power-drawbar-on-my-bridgeport-clone-mill.2701/

 

[lucsimoneau]

Might be a silly question, but the only way to loosen the R8 tooling is to lock the Spindle Cap with a 24mm wrench then unscrew the 12mm drawbar (see picture). So if I want this to be a "one handed" operation so I can catch the tool coming out of the spindle, I will need to lower a retaining plate over the spindle cap then have to lower the 12mm ratchet box over the drawbar and operate the airgun (or electric gun, whatever.)

The documentation of the PM-30MV specifically states "Do NOT try to lock the spindle using the flats on the spindle cap; this is screwed onto the spindle to secure a retaining clip above the return spring cup". The PM-30MV has flats on the spindle that are meant to be used to release the R8 tooling.

The CX601 spindle doesn't have flats on the spindle, so how else to release or secure the tooling with the drawbar? I've been doing it this way ever since I've had my machine.

Nice write up John on your installation ... will have to look into your solution.

My current head configuration has changed since I've put in a timing belt and pulleys. Should have enough room to fit the power draw bar.

Thanks for the replies!

 

[Aliva]

Here's my draw bar post 23

Power drawbar on my Bridgeport clone mill

Please try again That fixed it. Looks good!

canadianhobbymetalworkers.com

 

[lucsimoneau]

Ok, here's part of my design process ... comments are welcome as I'm in the planning stage.

First, I need to keep the spindle from rotating before I can screw in or out the drawbar, so using a 1/4 inch plate should do the job:

Down position: Up position:

Used the info from previous posts to use 16mm linear bushings with guide posts attached with appropriate hardware:

Adding top plate to hold the air gun with same bushings:

Added pneumatic butterfly air wrench into model to see how things fit, will need to adjust for the actual model that I need to purchase. Also added a 12 point 14mm socket to capture the 12mm square drawbar head:

Now, need a subplate that will hold the guide rods and attach to the top of the mill's head, secured by 4x M6 socket head cap screws:

Final assembly in up and down positions:

Up position: Middle position: Down position:

Will need to find springs that will fit and limit the upper position stroke and make a handle ... will keep you posted.
Cheers!