Material suggestions?

[Highpower]

(04-02-2015, 11:35 AM)dallen Wrote: use a carbide roughing endmill to cut the teeth on the ratchet lot cheaper then buying an insert cutter.

You are taking away my excuse to the boss to buy a face mill.... 

[dallen]

(04-02-2015, 12:45 PM)Highpower Wrote:

(04-02-2015, 11:35 AM)dallen Wrote: use a carbide roughing endmill to cut the teeth on the ratchet lot cheaper then buying an insert cutter.

You are taking away my excuse to the boss to buy a face mill.... 

tell the boss you need both

[Highpower]

I pulled the ratchet off to get dimensions. It is keyed to the pinion as I thought I remembered. I was really curious about what I have here, so I stroked it with a file a few times. No problem shaving off bright shiny chips so it's definitely not hardened.  So I'll just go with the annealed 4140.
I'm going to be hosed anyway because I think the largest broach I have is 3/8", and this key way appears to be 10mm.   

Yeah, yeah, get the file out - I know...   

   

[dallen]

your welcome to drop by and use one of the shapers to cut the keyway with.

DA

[Highpower]

I would have loved to do that David. I've never even been up close to a shaper much less run one.   

But that would be a long drive for one keyway, and I've already committed myself to the job. I just ordered a slug of 4140 annealed for the ratchet, and another slug of 4140HT to make a sleeve to fit the I.D. so I can use my 3/8" broach to take out the majority of material for the keyway. And thanks to Ed, I wound up adding a couple of lengths of that 7/8" he was talking about in the 'fire sale'. What goes around comes around I guess. Like he's said in the past, we love spending other peoples money.   

[f350ca]

I've never used a broach so bear with me on this one. If you made the normal sleeve and cut the 3/8 keyway then made another sleeve with the groove cut 7/16, the extra 1/16 to one side, then put a 1/16 spacer in the grove to hold the broach over, then a 1/2 inch sleeve and use a 1/8 spacer. Essentially cut the standard 3/8 keyway then broach out the two sides to get 1/2.
Maybe?

[Mayhem]

If you have a lathe, you can cut a keyway:

http://bbs.homeshopmachinist.net/threads...in-a-Lathe

On the first page there are two options shown. One is using a boring bar and moving the carriage to make the the cut. The second is an attachment that uses a handle to achieve linear motion. Rob Wilson posted a thread here on his much more elegant version but the forum search tool and I are not good friends...

[Highpower]

Greg, I can't say it's never been done before, but I've never heard of anyone trying that. It sounds like a recipe for disaster to me though, trying to cut only on one edge of the broach. Any bit of side load on a broach will snap them in half like a dried twig. Too expensive for me to experiment with I'm afraid.   

I will most likely finish up the sides with the method that Darren talked about. I've done the same type of thing using the quill on my mill to square up inside corners with very good results. My poor man's manual shaper. 

[dallen]

use the 3/8 inch broach to cut the keyway in the ratchet, then make a T shaped key to fit both the pinon and ratchet, I seriously doubt that you will be able to shear the key by pulling on the handle.

[Highpower]

I love this place. Someone always has another way of looking at a design or a problem at hand and can offer up another way to skin a cat. No matter what kind of tools you have available (or not) you guys come up with ways to make it work. Or point out possible issues that I would not have thought about on my own. The difference HERE is, it's always done with a smile instead of a scowl like you find at so many other places on the interwebs. I still have a lot to learn about various metals and I'm looking forward to all the education I can get.

You guys are simply the best. IMHO of course....