Rotary Broaching

[rhino]

Hey Fellow Cncoligists,

Been searching for a while for a broach i used in a cnc lathe at a place where i started my apprenticeship. Voila! i found it this morning! the process is called rotary broaching "duh!." I saw a website called http://www.slatertools.com or http://www.rotarybroaching.com (same website). anyway there is a video link up the top of the page on how it works.

Has anyone had any experience with this stuff? Please post your thoughts.

Rhino

[laka]

We've used them before in brass, alum, and some 4140.

If you set them up properly, they work very well. Just make sure to keep her greased.

[little bubba]

Once you grasp how they work it makes perfect sense. A very powerful tool to have in your backpocket.

They take a lot of force, my experience is a 12 point 3/8 hex on a 17-4 bolt. Hundreds of them. Its a fantastic process, but your equipment needs to be up to it. I blew out the power feed on two lathes and popped a servo on a less than powerful CNC. Ended up with a cheater bar on the turret. I was very sore for a while.

[djr76]

I just did a job in plastics making pulleys with 11/16 hex, the tool works great. Its a little tricky in plastics not getting blowout on the backside of a through hole but all in all a very cool tool.

[peter@slater]

Rhino, Did you get a chance to look at the Customer Showcase at the bottom of the rotarybroaching.com page? There's a bunch of comments about how it's been for those guys who are using the tooling. Set-up is easier now if you can use Slater's adjustment free tool holders.

[MazakMikeO]

Just be sure to get the bore size right and it's fine. Used to machine a 6mm hex in 316 handles (thousands of them) and it was fine.

[fuzzyracing1967]

That is damm cool,never scene one of those before! In the video it makes a quick refferance to keyways,but on the site I didn't find any tooling to do keyways,or did I miss it somehow?

[peter@slater]

There are some limitations with forms that can be broached using rotary broaching tools, and keyways are one of them. For whatever reason, single keyways can be almost impossible to rotary broach. The cutting action requires the broach to 'wobble' or rotate the full diameter of the form, and because the keyway is only on one side, the uneven pressure often causes the broaches to break - resulting in poor tool life. Keyway depth must be shallow as well.
However, there is any easy solution! If permissable, just add a few more keyways, and then you will even out the form. A quick fax to your rotary broach manufaturer, with OD and ID dims, will get you an answer if it will work, and how much it will cost.

[rhino]

Peter@slater:
I take it you are a rep? am i correct? i have left numerous e-mails with the slater tools "contact us" page to contact "ME" but have had no reply.
Do you have Australian Reps? Let me know or pm me some contact details please.

laka:
Out of curoiosity, what size were you broaching in 4140? when i put this concept to my boss i had a couple of jobs in mind. it will beat the SH*T out of welding cap screw heads into the head of our products!

[peter@slater]

I do some technical work for Slater. We were having some 'issues' with the contact us page on our website, but I believe it's fixed now. If you need anything, send me a personal message and I'll take of you.

4140 is great for rotary broaching. It most cases it also has very good tool life, probably up to about 20mm/.75inch. Alot depends on the depth of the hole, pre-drill size and capability of your machine.

[polygon]

Here is a great video demonstrating the rotary broaching process using a Bridgeport:

Rotary Broaching on a Bridgeport - YouTube

Rotary Broaching on a Bridgeport - YouTube