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Re: HF 5980 3 in 1 Mill Chuck Stuck

Posted: Mon Nov 28, 2011 3:10 pm
by BentTooner
Hi,

Ok, got it about NOT spreading the slot.

I've made a new wedge that increases size in the vertical direction and it's still not moving the tool holder/chuck at all. Because of the way the wedge enters the slot, one side of the slot is NOT pushing on anything while the other side makes contact. So, I've tried putting the wedge in from each side to try to move things equally. But still no luck...

I suspect the piece has "welded" in place by corrosion. Also, maybe side loads from the prior owner milling with the chuck (rather than drilling) have caused some problem. It's hard for me know what's going on because I cannot see what's in there...

I'm imagining the chuck has a straight (non-tapered) shaft and the 'drill taper stock' is a hollow tube with a taper like a spring collet on my Dremel tool. I'm imagining that the chuck's shaft slides inside the hollow tube and then the tube and chuck slide up, into the quill's hole. Then, the draw bar threads into the top of chuck (it doesn't look as if the draw bar threads into the tube) and pulls the chuck up, farther into the taper of the quill. I'm guessing the taper squeezes the sides of the tube to grip the straight shaft on the chuck. Do I have that right?

I'm thinking the problem is that the tube is stuck in the quill and so the chuck's shaft is stuck in the tube. Even if I got the chuck out, the tube would still be stuck in the quill.

Again, thanks for all the advice!

Re: HF 5980 3 in 1 Mill Chuck Stuck

Posted: Mon Nov 28, 2011 5:26 pm
by Torch
BentTooner wrote:I'm imagining the chuck has a straight (non-tapered) shaft and the 'drill taper stock' is a hollow tube with a taper like a spring collet on my Dremel tool. I'm imagining that the chuck's shaft slides inside the hollow tube and then the tube and chuck slide up, into the quill's hole. Then, the draw bar threads into the top of chuck (it doesn't look as if the draw bar threads into the tube) and pulls the chuck up, farther into the taper of the quill. I'm guessing the taper squeezes the sides of the tube to grip the straight shaft on the chuck. Do I have that right?
The "drill taper" is a solid chunk of steel (well, except for the tapped hole on top for the draw bolt). It is tapered on both ends. The upper end is a "Morse Taper" (approx. 5/8" per foot, etc.) and the bottom end is also tapered, probably a "Jacob's Taper", since most drill chucks are sized to fit a JT standard taper.

Have a look at this web page. It's got lots of pictures which might help you visualize what's going on and what you need to do.

Re: HF 5980 3 in 1 Mill Chuck Stuck

Posted: Mon Nov 28, 2011 6:16 pm
by BentTooner
Hi,

Thanks for the link.

I got it out! I saw a good picture of the 'tool wedge' on one of the posts on this site for this machine and then it clicked for me. So, I made a new wedge from 1/4" plate aluminum and, while it took some serious power, the chuck finally broke free. It chewed up the aluminum wedge up a bit but I would rather have the wedge damaged than the machine.

It doesn't have any corrosion on it so I'm not sure why it was stuck so hard. Anyway, I took some pictures.

Here's the chuck:
MT2 Mill Chuck
MT2 Mill Chuck
Here's a couple of pix of the tool wedge:
Tool Wedge <br />5&quot; long<br />1 5/8&quot; tapering to 5/8&quot;<br />1/4&quot; plate aluminum<br />Rounded edges
Tool Wedge
5" long
1 5/8" tapering to 5/8"
1/4" plate aluminum
Rounded edges
Another angle on tool wedge
Another angle on tool wedge
Again, thanks so much for hanging in there with me!! It was a big help!!

Now I can start working on a new drawbar to hold the SAE threaded end mill holders...

Re: HF 5980 3 in 1 Mill Chuck Stuck

Posted: Mon Nov 28, 2011 8:38 pm
by Torch
BentTooner wrote:I got it out!
:D :D :D :D :D :D
while it took some serious power, the chuck finally broke free. It chewed up the aluminum wedge up a bit but I would rather have the wedge damaged than the machine.

It doesn't have any corrosion on it so I'm not sure why it was stuck so hard.
Yup. They do that. The Morse Taper is a long shallow taper friction fit, designed to withstand a fair bit of torque. There's a lot of stiction there! It's also possible that the spindle was warm but the chuck was cold the last time it was installed. Add a big boy with a long wrench...
Again, thanks so much for hanging in there with me!! It was a big help!!
Less than 2 years ago, I was the newbie and guys like Harold and Glenn and Steve and Bill and, well, all the others, "hung in there" for me. It's kind of fun to finally be able to help someone for a change :lol:

Re: HF 5980 3 in 1 Mill Chuck Stuck

Posted: Thu Dec 01, 2011 7:22 pm
by mac.doogle
Mine was stuck the same way, If this helps I had to use a tie rod knocker to get it loose. It worked fine and did not damage anything. Leave some of the drawbar screwed in some. It worked for me.

Re: HF 5980 3 in 1 Mill Chuck Stuck

Posted: Fri Dec 02, 2011 9:16 am
by BentTooner
MacD

Thanks for the great ideas. I have a tie rod pickle. I'll check it out. Also, that's a great tip to keep the draw bar threaded a bit so the chuck can't drop out.

Thanks again to all!

Re: HF 5980 3 in 1 Mill Chuck Stuck

Posted: Wed Dec 13, 2023 4:09 pm
by Jerry
My T5980's MT2/Jacobs taper fought my attempts to remove. I did get it out, but here's what I learned:
1) A tie rod knocker will separate the chuck from the Jacobs portion of the assembly, but the chuck let's loose from the Jacob's part of the taper. In fact, if anything, using a tie rod fork may drive the MT2 tighter into the sleeve.
2) My MT2 taper is short, it ends about 1/4 inch below the slot where one is supposed to insert a wedge. That means no wedge will work to free the Morris taper.
3) As stated in another thread, screw the drawbar into the taper, back the top nut off about 1-2 threads. I actually replaced the top nut with a 10mm hexanganal connecting nut to extend the top of the drawbar farther out of the drive pulley and to provide a bigger surface to hit.
4) Small taps did nothing. A couple of hits using the mass of a medium-sized brass hammer did the job.
5) Once out, if you want to be able to use the sleeve slot and a wedge to remove the taper, get a piece of 10mm threaded rod, screw into taper, cut to length so that the rod protrudes up into the middle of the sleeve slot. Now the wedge will work.

Re: HF 5980 3 in 1 Mill Chuck Stuck

Posted: Wed Dec 13, 2023 4:50 pm
by Harold_V
Jerry wrote: Wed Dec 13, 2023 4:09 pm 2) My MT2 taper is short, it ends about 1/4 inch below the slot where one is supposed to insert a wedge. That means no wedge will work to free the Morris taper.
First, that isn't true. It takes but a little effort to drop in a piece that would allow a proper wedge to engage, so it could easily dislodge the taper, which is NOT a MORRIS, but a MORSE. To my knowledge, there is no Morris taper used in machine tools. Please correct me if I'm wrong. We should not be propagating misinformation on this or any venue.

H

Re: HF 5980 3 in 1 Mill Chuck Stuck

Posted: Sat Dec 16, 2023 2:20 pm
by toddalin
I have a Tri-Power that uses the R8 collets and what I do is to remove the drawbolt and use a garage door spring tensioner tool in its place to whack. I even have a grommet around the tool to that it does not fall through when the collet pops out.
https://www.amazon.com/Winding-Torsion- ... 1BEALw_wcB