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louigi
10-25-2012, 03:53 PM
I removed the right table crank on the Bridgeport while attempting to remove the AS235 power feed unit for repair. The #7 Woodruff key is stuck in the slot. It appears to be glued down or maybe even soldered in. I have tried heating it with a propane torch to loosen it, but did nothing but discolor the shaft. Any idea what to do next will be extremely appreciated.

krutch
10-25-2012, 04:03 PM
When I can, I will use a small punch to persuade the key to move. Gentile taps so as to not damage the shaft or key. Work the key back an forth or drive it around the seat until it can be grabed with pliers. I have used a pair of cutter plier to grab the key and pry a key out. The key will be gouged by the cutter and you chance damage to the shaft if not careful.

EddyCurr
10-25-2012, 04:11 PM
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Black_Moons
10-25-2012, 04:52 PM
Likey rusted in good. Was there a good reason you needed to remove it?
Usally, they are much better rusted in place then falling out mid assembley, somewhere in your shop.

RussZHC
10-25-2012, 05:15 PM
When I can, I will use a small punch to persuade the key to move. Gentile taps so as to not damage the shaft or key

pretty much that, start on the end away from where you have the best access, drive that end down, what IMO you are after is to have the end of the key where you can get at it "rock up" in the key seat...that higher exposed corner may allow you to grab it...I have, with limited success, taken a chisel and with a good, well place rap, with as much "up" angle as possible, on that exposed corner, knocked the key out...problem is you will likely only get one shot at that, unless it is hardened, the key will either move more, get pushed out completely, or you will shear off that exposed corner...if it is the latter, not good as that corner will now also, likely, have mushroomed somewhat which may seat the key even more (what is left of it)...its the keyseat and the shaft you have to save...with shaft being priority, you can cut another keyseat but...

For what its worth, try cold instead of heat...before trying the above

Edit to add: I have drilled holes partially through to weaken the key...there is a "pucker factor" there...but if its gotta go, its gotta go [noob hack so YMMV]

louigi
10-25-2012, 05:16 PM
Krutch,
I've tried that, short of using a pneumatic hammer. I've pushed, pulled, tapped, hammered, heated, repeated and nothing dislodges it. I'm thinking of making a miniture slide hammer and pulling it.

louigi
10-25-2012, 05:18 PM
Black_Moons,
I'm removing the AS235 power unit to replace the speed setting pot. The shim washers will not pass the key.

oldtiffie
10-25-2012, 05:21 PM
Is there really a reason to remove that key now?

As the OP can see and get to the "Woodruff" "half-round"" key it seems to mean that the power unit had been removed so it should go back on easily - unless he mangles the key - and still can't get it out.

If it were me and I wanted to use the power unit on the mill I'd probably just put the power unit back on and use it.

Think about the key later when you have enough time.

louigi
10-25-2012, 05:22 PM
RussZHC,
The key is not hardened. If I can't budge it and can't pull it with a 'to be built' slide hammer, I will file it off, make needed repairs to the drive unit, remove the whole thing and cut a new key on a different spot using the lathe. About 15 hours, I expect.

How cold should it make the shaft? Frozen CO2? Liquid nitrogen?

rohart
10-25-2012, 06:11 PM
Drill through from the other side and use a drift. Don't drill too deep !

rkepler
10-25-2012, 08:56 PM
You could carve it out with a Dremel and a cutting disc:

http://www.kepler-eng.com/images/woodruff_key.jpg

Doozer
10-25-2012, 09:01 PM
http://www.harborfreight.com/media/catalog/product/cache/1/image/9df78eab33525d08d6e5fb8d27136e95/i/m/image_17276.jpg

The proper tool for the job.

--Doozer

RussZHC
10-25-2012, 09:43 PM
rkepler: I like that idea...funny how sometimes another better choice (than drilling, IMO) can't be seen

"Cold", not sure on that either...my simple thought is to just sometimes do the opposite, if heat did not work maybe cold will (e.g. if say it was glued in, and heat had little effect it maybe susceptible to cold), I was thinking more regular ice surrounding the area, if two different types of metal...plus it costs next to nothing to try...like you said, file away top, remove parts and make another seat could be "it"

Arcane
10-26-2012, 02:41 AM
Get a good sized pair of these http://www.hyperclaw.com/pic/products/diagonal-cutting-612-L.jpg and grip the key at one end parallel to the shaft and, with a prying motion, lift it up and out of the slot.

dp
10-26-2012, 02:46 AM
Get a good sized pair of these ... and grip the key at one end parallel to the shaft and, with a prying motion, lift it up and out of the slot.

That's what I do. The nippers in an earlier post work well, too.

camdigger
10-26-2012, 03:00 AM
A heavy application of your favorite lubricant will help. Kroil, WD40, 50-50 Acetone and ATF, wax, kerosene, diesel fuel, etc.

********Obligatory caution for the safety Nazis - Any lubricant worth applying will burn! Some faster and more voilently than others, but all wiil burn! Flammable products and open flame must be used with appropriate precautions and techniques.

Forrest Addy
10-26-2012, 05:08 AM
Doozer is dead right. Use end nippers.

Take a careful pinch on the key. Get a death grip on the plier handles to imbed the jaws in the key and rock it back and forth while pulling. If the jaws don't slip, the key should work out in a couple of wiggles LockTite or no LocTite.

I have a pair of end nippers I use just for Woodruff keys. I belt sanded the face back until it was not quite flush with the nipper edges.

Black Forest
10-26-2012, 07:20 AM
Two days ago I had a key stuck in a slot on a MK5 tool holder for my horizontal mill. I also couldn't get it out with a pair of nippers. So I drilled and tapped the key. I used a bottoming tap. Then it was a simple matter to put a small bolt in the key and press it out with the bolt. Worked perfect. The key was 10mm wide. When I put it back I put a grub screw in the hole that ended up flush with the top of the key.

Abner
10-26-2012, 09:34 AM
I just had this problem.

First time; my key was bigger so I was able to drill, tap, and use a hex bolt to jack the key out.

Second time; (Do not ask why there was a second time :mad:). I welded a bolt, head to the key. I used a piece of square tubing for a spacer and a piece of FB with a hole across the tubing. Passed the bolt through the FB, nutted it, simply tightened the nut and out she came. Worked very very well.

louigi
10-26-2012, 09:51 AM
Thanks for all the excellent ideas, guys. I liked Black Forrest's thoughts on jacking it out, Doozer's on the nippers (I have a pair of flush head nippers and tried them without effect). What I'm going to do is cut it out with the Dremmel like Rkepler suggested... Thanks. Problem solved.

krutch
10-26-2012, 10:59 AM
Krutch,
I've tried that, short of using a pneumatic hammer. I've pushed, pulled, tapped, hammered, heated, repeated and nothing dislodges it. I'm thinking of making a miniture slide hammer and pulling it.

Can you get at the end of the key with a tiny chisel? Or a prick punch? If so, work on the end with access to get under the key and lift it. The key is a flat key, not a woodruff. The chisel or punch will raise an edge which you should be able to work on to raise the key. If this still doesn't work, file or grind the key to remove the other equipment, then go back to work on the key. You might be able to drill a series of holes in the key center to collaspe the key into it'self. You most likely find the key has a burr which was forced into the keyway. That key does not have to be tight in the way. On my "off-shore" mills the keys are a good fit but not press fit. The BPs I have experiance with were not press fit either. Destroy the key if you must but not the way if possible. Fit a new key to have a 'drag' fit in the way. A press fit is not needed. The keyed parts will be held by the nut pressure and the key only keeps thing from slipping.

krutch
10-26-2012, 11:07 AM
I read where you might "re-key" in another spot. Keep in mind the handles are keyed for the handle 'ball' to balance against each other on the shaft. Not a big deal for hand cranking, but with power feed, at least at rapid, you can have shutter with the handle 'balls' lined up.

1-800miner
10-26-2012, 11:30 PM
how about broaching a keyway in the washer so it passes over the woodruff.

Mcostello
10-27-2012, 09:39 PM
If the washer could be cut apart it would solve one problem. A washer could have clearance filed in it for reassembly. Depends if another part also needed to come off.

aboard_epsilon
10-28-2012, 08:22 AM
This is the tool i have ..extract from one of my postings on another forum follows :-

Sometimes ..as in my case the woodruff keys are a bugger to get out .
pics below are of the woodruff key that locates the bottom cambelt toothed pulley.
This has to be removed before you can get the oil pump off.
They are got out by taping them on one end and swivelling them in the hole .
To do this you have to make or adapt a tool.

http://img.photobucket.com/albums/v190/aboard_epsilon/rover%20420/chisel1.jpg

http://img.photobucket.com/albums/v190/aboard_epsilon/rover%20420/chisel2.jpg

http://img.photobucket.com/albums/v190/aboard_epsilon/rover%20420/woodruff2.jpg

aboard_epsilon
10-28-2012, 08:23 AM
http://img.photobucket.com/albums/v190/aboard_epsilon/rover%20420/woodruff1.jpg

http://img.photobucket.com/albums/v190/aboard_epsilon/rover%20420/woodruffinhand.jpg

all the best...markj

Timleech
10-28-2012, 08:44 AM
This is the tool i have ..extract from one of my postings on another forum follows :-

Sometimes ..as in my case the woodruff keys are a bugger to get out .
pics below are of the woodruff key that locates the bottom cambelt toothed pulley.
This has to be removed before you can get the oil pump off.
They are got out by taping them on one end and swivelling them in the hole .
To do this you have to make or adapt a tool.



That looks like what I know as a 'Cow Mouthed' chisel. Why it's called that I've no idea, can't see much resemblance.

Tim

bborr01
10-28-2012, 10:20 AM
You could carve it out with a Dremel and a cutting disc:

http://www.kepler-eng.com/images/woodruff_key.jpg

That is exactly how I did it. The first time I had to remove one it came out by tapping it from the end with a chisel. The second one was frozen in like it was welded in. The dremel with a cutoff wheel finally did it.

edit: I think the reason these keys are so tight in the first place is to keep the dials from getting slop in them.

Brian