Cant remove drill chuck grizzly g8689 mini mill

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Jon.unique

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hi
Need help drill chuck will not come out..

I bought it used so have no history on machine

I loosen draw bar few turns the hit draw bar top hard with a heavy brass hammer and it wont budge..not even a thousanths of an inch

Any ideas why?

Maybe prev owner used some type of epoxy to mount it?...
 
I have stopped trying since i dont want to damage my machine....will contact grizzly tech support to see if machine is designed wrong or defect....in meantime any help,would be appreciated...a morse taper should not benthat tight it should come out easily with a simple tap on top
....something is obviously wrong
 
That is how it is done. If you are afraid to damage the draw bolt, remove it and insert the largest diameter rod that will fit. The previous owner may have had a shaving or two on the taper when installed and it is jammed. Just going to take some love taps to dis-lodge it from the bore.
 
Thanks ill try that ..im sure it will create more force than using the draw bar threads to remove it...and will be putting more force where is needed on the outer edge of the taper and notbthe cenetr like the draw bar does....i sprayed pb blast ....will wait till tomorrow...i think what happened is prv owner kept chuck in there all the time and it fused to,spindle via oxidation rust....im not happy...very frustrating .just trying to change tools and i cant...should be a simple task
 
I just dont want to damage the mill....hitting hard is not recommeneded since it can damage the bearings...i was tkhinking ofvremoving the headstock is not too hard of task and press it out with my 3ton arbor press
 
I used wood blcks to supportbthe headstock when tapping..to take stress off of other areas...ideally maybe would be better to actually support the outer edge of the spindle bore instead..
 
I too would use a piece of wood to support the headstock. I would also try to apply some penetrating oil into the spindle.
BTW, a 50/50 mix of acetone and ATF (automatic transmission fluid) woks great in place of penetrating oil.
 
Thanks...i got it out but not without issues,,i used pb blast overnight...and then ,,i first used a 1/2 daimsteel rod but it kept getting wedged inside the 12mm threaded chuck..and ruined the threads....so i then ..tried a 5/8 diameter steel rod.as a punch.....but when i was hitting it it mushroomed out a bit on other end and i had to vise grip it and hammer on it to remove it...so i stopped that method...chuck didnt budge ...the hole is exactly .629 diameter....so i then went and got my 5lb hammer and with a few good wacks it came out.....obviously you should not have to use a 5lb hammer .....but in my case i had to.....i will not keep any tool in the spindle as long as i own it...so this will not happen again..

Thanks to everyone....in the end you cant beat brute force but its just not good on the machine....had no choice though
 
Oh when i was hitting it with the 5lb i was hitting the orig drawbar head.....i couldnt find a 12mm long bolt to hit on but thts what im going to buy and use next time....a 12,mm bolt is cheaper than buying a new drawbar ....come to think of it i guess u could use a 12mm bolt as a draw bar anyways :)
 
Jon
You shouldn't need to have recourse to a 5lb hammer!
All that a Morse taper needs to be tightened sufficiently to avoid the drill chuck or whatever is in the mill taper.
However, I DO agree with utilising cheap metric studding and obviously nuts to make- all sorts of things. I make my own tee nuts from them and square stock and depending on how the mood takes me, I either silver solder them or give them a flash on my little Mig welder.

Actually, I have a bit of rod tapped to go into my various chucks but with a bit of hexagon threaded couple which has been welded on. You might find in practice that other chucks are threaded Whitworth, Fine or Coarse, Metric or UNF and the common sense view is to have the across flats of all of them to take the one spanner.

If you haven't come across such needs, you soon will. FWIW I can interchange Morse tapers on my Myford , the Sieg C4, the mill drill, the tool and cutter grinder and all the various rotary tables and dividing heads- apart from my little 3 inch one. You may want to consider a a pair of MT reamers, one for roughing out and the other for finishing. But I digress a bit as you may need a reamer if you have raised a burr in your mill- or need a scraper or fine file.
Sadly, these things happen

Regards

Norm
 
I use some anti-seize copper paste to avoid this occurring. I too had reservations about striking the draw bar, I keep a lump hammer nearby. My mill (bearings) has survived this treatment for over 20 years and I doubt that the roller bearings have been affected over all that time. I do find that the taper frees off better in the afternoon when the shop temperature has risen than it does first thing in the day! Some time ago I experimented with a self extracting mechanism on the top of the mandrel but the forces involved to break the taper are considerable and defeated me eventually i.e. the self extract bearing broke!
 
quote{I do find that the taper frees off better in the afternoon when the shop temperature has risen than it does first thing in the day!}
That would work in my shop, this summer it has been 100 F some days..if your taper is a R-8 it should free with few light blows with the drawbar hammer, if its a Morse taper I could understand that it could be frozen up..But anyway glad you have it removed..
 
I made a self releasing drawbar for my X2-mill some years ago - it was published in Model Engineers' Workshop No.223 in December 2014 and has ben invaluable since then. I made two drawbars, one metric M12 and the other 3/8x16. At the same time I changed from gears to poly-V belt. No more hammering on the drawbar, just a quick half turn with the spanner and I can unscrew the MT3 taper by hand. I am more than pleased with the result.
The cap on the left has inside 1 1/16 x 16TPI - LEFT HAND thread! but check on your mill anyway and sits on the shortened nut on the top of the spindle, the 7/8" collar on the drawbar rides on the spindle itself and has as little play to the cap above as is possible without binding.
I knurled the top of the cap for easy removal, a 1/4" hole might help if it comes stuck after some time - don't forget - lefthand , and use the spanner to tighten the drawbar just a bit over finger tight.
 

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I think you hit the nail on the head when you said "use the spanner to tighten the drawbar just a bit over finger tight." I've had MT3 tapers slip on a couple of times and had to polish out the resulting burrs so I'm perhaps a little heavy handed on the spanner! An MT3 taper, if left un-removed for more than a week, can become quite stubborn, I believe the copper paste does help in this situation. However I reiterate that the hammer blows do not seem to have had any detrimental effect on the spindle bearings so far.
 

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