loose morse taper

gary doby

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56
Location
North Carolina Foothills
I recently bought a set of collet chucks for my Jet mini lathe with a MT2 taper. I am having trouble keeping it from coming loose while turning. Any similar issues or comments to see if I am doing something wrong?
 
Had a similar experience with a drill press. Cleaned the chuck and taper thoroughly, and I mean thoroughly. All was well after that.
 
Gary.....Check the end of your morse taper.....does it have a theaded hole in it? I use a morse taper jacobs chuck to hold my b/s mandrel. The jacobs chuck kept coming out while turning with it. Then I noticed the threaded hole in the end of the morse taper. I got a long 1/4x20 threaded bolt, washer and wing nut. I put the bolt with the wing nut and washer on it ...through the hole in handle on the headstock and screwed it into the hole in the morse taper. Then I tightened the wing nut up until the washer is pressed tightly against the handle. The morse taper....the jacobs chuck stays put and I can turn bottlestoppers.....
 
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Glenn's suggestion was the first thought that came to me, too. Try cleaning the taper and the hole you're putting it into thoroughly with mineral spirits.

Ken's suggestion for a piece of all-thread through the spindle is also a good recommendation after you get things cleaned up.
 
If you read the warning (CYA) label on a jacobs chuck with Morris taper, it will say "For Tailstock use Only" Because the extra size and force exerted, exceeds what a Morris taper will control in that situation. With that type of fitting it may be necessary to add a threaded rod to hold the taper in place.

Along with what others have said, Clean, debur, etc. Make sure there is more surface tension to control the taper. Even slight sanding dust and lint can create a gap and loose the surface tension. Sometimes WD40 sprayed on the hole and taper will act as surface tension sealer.

Don't be afraid to give it a good "Thump" with a deadblow or wood mallot. (one reason I often have my students make a Mallot as their first project, you need one from time to time)
 
I think they pack those things for the voyage from China in the same kind of grease that they cook eggrolls in. I know the eggrolls always loosen me up. Anyway, a thorough cleaning on both the male and female parts usually works. Remember if the collett chuck had any grease or oil it probably got a little inside the spindle of the lathe too.
 
Dont' know if this will help, but....

When I bought my drill press, I had a MT3 to install. I throughly cleaned it an put it in the freezer over night. The following day, I removed it from the freezer and rushed to the shop where I placed my chuck, face down, on the floor and inserted the MT into the chuck. I put a board over the MT end and hit it with a ball peen hammer. I then inserted that assembly in the drill press and cranked down on it like I was trying to drill through a piece of steel plate using a dull bit.

That puppy is in tight.:thumb:

Good Luck,
 
I like the freezing idea, Ken, but that's probably a bit tighter than Gary wants the collet chuck on his mini lathe. :D He's be using the heat wrench to remove it.
 
I like the freezing idea, Ken, but that's probably a bit tighter than Gary wants the collet chuck on his mini lathe. :D He's be using the heat wrench to remove it.


Right, Freeze is good for permanant install but like you said, have to do sopme major work to remove.

Most often fellows are reluctant to give it a good Whack! to seat the taper, If you can ruin it by hitting with a wood mallot or dead blow hammer then it isn't worth using anyway. Thunk it a good lick and it will stick (providing the surfaces are clean.)
 
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