Ideas for removing key from shaft

I have a motor that has a keyed shaft, and I need to remove the key.
The shaft is about 15mm diameter, the key is about 6mm wide (it's a German
motor, so it's all in mm), with rounded ends. The keyway is only slightly longer than the key. It looks like the keyway was milled with an end mill, and the key either glued or pressed into the keyway.
The thing came from the factory with a rubber retainer* around the key, which gives me hope that the key can be removed -- but I haven't been able to do it just by grabbing it with a vice grip and pulling.
Any suggestions about how the key may be retained in there, and how to get it out without damaging the shaft?
* Really it's a rubber band. But it's not a piece of office-supply crap -- it's a rubber band sourced by German machinists who take pride in their work, so it's black and thick and can probably be soaked in gasoline for a day, be wiped off, and still be like new. So I can't quite call it a rubber band.
--

Tim Wescott
Wescott Design Services
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Monday, October 6, 2014 12:19:03 PM UTC-7, Tim Wescott wrote:

If all else fails, one could drill and tap the key (they're usually soft enough), and pull it out with a slide hammer.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 06 Oct 2014 12:27:39 -0700, whit3rd wrote:

Thanks. Eric's vise-ridden answer was the right one, but had it failed I think yours would have worked a treat.
--

Tim Wescott
Wescott Design Services
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

I find many uses for a small insert or drill press vise http://www.shars.com/products/view/108/Precision_Toolmakers_Insert_Vise_1quot and this would be one of them.
-jsw
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload


I've got three of those little insert vises. They are incredibly handy when transferring a small part from one machine to another. They are also very handy when machining a part from more than one side. I recently used on a cylindrical part. I turned it on the lathe, clamped the flat side on the step jaws of that little vise, and machined it from two sides on the CHCNC mill. Very handy when working with small parts. You don't align to the part after the first setup. You just flip the vise and do the other side. If its not high tolerance you can just align the little vise corner to corner with the bigger vise on the table.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

It's a _key_. By definition, it sticks out above the shaft o.d.
Get a sharp,thin prick punch, and engage one end of the key (as high as you can get, and still get good 'meat', angle the punch down as far as you can from that point toward the shaft, and give it a smart whack with a small, hard hammer. That should lift one end of the key, if only a little.
Another alternative is to give it a mild whack down INTO the keyway, or milder sideways, and try to break whatever sealant they've put in there.
Keys aways come out, and usually with no damage to the keyway... only the key itself; cheap, replacable. LLoyd
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 06 Oct 2014 14:19:03 -0500, Tim Wescott

Greetings Tim, When I need to get a stubborn key out, and can hold the shaft in my hands, I clamp the key in the Kurt Anglock vise. Then I lift the other end of the shaft so that the key comes out at an angle. The vise grabs better than vise grips. If I can't get the shfat to the vise I use visegrips, grabbing as hard as possible at one end of the key, and pulling it out that way. This method takes less force that trying to pull the whole length of the key at once. Eric
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 06 Oct 2014 13:21:59 -0700, etpm wrote:

Thanks. I don't have a Kurt vice, but it worked great with a bench vice, and didn't mar the key significantly at all (I can't see it -- just feel a bit of a ridge on the side that was pulled away).
--

Tim Wescott
Wescott Design Services
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 06 Oct 2014 16:10:08 -0500, Tim Wescott

Glad I could help. Eric
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 06 Oct 2014 16:10:08 -0500, Tim Wescott

A couple swipes across a diamond hone will take that right off, Tim. Until a few days ago, I had more diamonds than files, but I just came home from Gunner's with about 40 files and rasps. </gloat2>
--
Give me the luxuries of life.
I can live without the necessities.
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Thu, 09 Oct 2014 08:13:43 -0700, Larry Jaques wrote:

Given that the key needed to come off so that I could put some prototype hardware on, and the key would only be in the way, the key and motor will probably remain separated for life.
But yes, it'd be easy enough to clean up.
--

Tim Wescott
Wescott Design Services
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 06 Oct 2014 14:19:03 -0500, Tim Wescott

To remove the key - which, from your description, is a "woodruff" key bump it on the end with a drift - a brass one if you are really fussy - and it will walk right out of the keyway.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 06 Oct 2014 17:49:18 -0400, snipped-for-privacy@snyder.on.ca wrote:

I think he's talking about a Pratt & Whitney key, which is like a plain square key but which has rounded ends.
--
Ed Huntress

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 06 Oct 2014 18:04:10 -0400, Ed Huntress wrote:

Yes, it's a Pratt & Whitney key, in a slot that fits it all around with no room to move it any direction except for up out of the slot.
Or, since it's from Germany, maybe it's a BMW key, or a Junkers Key, or something like that.
--

Tim Wescott
Wescott Design Services
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

In German it's a fitted "feather", specified by DIN 6885. http://de.wikipedia.org/wiki/Passfeder
-jsw
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 06 Oct 2014 18:21:18 -0500, Tim Wescott

OK - I can picture it now. Drift wouldn't work too well.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 06 Oct 2014 18:04:10 -0400, Ed Huntress

Thought of that after I posted - but the drift punch on the end works good for them too. - Generally.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@snyder.on.ca wrote:

I use a large pair of dikes, grab it on one end and then pull up lifting it out as the nose pushes down and prys the key out.
John
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Mon, 06 Oct 2014 17:49:18 -0400, clare wrote:

No, the keyway does not extend to the end of the shaft -- that's what I meant about "looks like it was made with and end mill" and "is only a bit longer than the key".
But, I got it out.
--

Tim Wescott
Wescott Design Services
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On Monday, October 6, 2014 3:19:03 PM UTC-4, Tim Wescott wrote:

Does the keyway come out to the end of the shaft? If it does, use a long pin punch and drive the key toward the end of the shaft.
On most U.S. motors the keyway in milled with something like a woodruff cutter. In that case there is kind of a ramp at the end of the keyway and you can drive the key toward it.
If the keyway is not open to the end of the shaft, I would put penetrating oil on the key and then tap it back and forth while cursing the Germans. The key may only move a few thousands , but it may still make it easier to pull.
Dan
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.