Hard to turn Delta DP Chuck

I have a Delta Drill Press. It is not really OLD iron; it is younger than my car. On the other hand the car acts like new and the Jacobs Chuck on the DP gets very difficult to adjust.

Twice in the past I have cleaned the chuck with mineral spirits. This makes the chuck work fine for a couple months and then it starts acting like I put chewing gum in it.

This time I removed the chuck and soaked it for a few hours in Klean Strip “Industiral Maintenance Coating Thinner provides good solvency and can be used in place of MEK, Toluene, Xylene and VM&P Naptha for thinning Industrial Maintenance Coatings.”

I did this because I did not want Royal Clark to be the only one who jumped into something before he had all of the answers. Anyway, did I do good, bad or indifferent with my choice of cleaner?

The procedure I used this time: Put the chuck in a can and covered it with the fluid. Let it soak a couple hours. Then every time I thought of it I would flip the DP switch and let it run for an honest 15 to 20 seconds. Part of the time I did this with the jaws wide open, sometimes with the jaws half way and sometime with them almost closed.

After each “swirl” I let the chuck drain a few seconds.

QUESTION: What should I do now?

Thanks in advance.

Enjoy,
JimB

My dad purchased a Delta DP back in the late 40’s or 50’s. It got a lot of use between my dad and me. The chuck was still working perfectly when I sold it 4-6 years ago.
 
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Maybe it needs some lubrication? Maybe the sovents washed out the factory lube.

WD40 would be easy but a disaster if it drips out.


Maybe something like melted beezwax or graphite powder up in there? Maybe both.

Or maybe a bigger key with some rubber hose slid over the handles to make it easier to torque?

key.jpg
 
If i had put that much solvent into a chuck, i wouldn't be comfortable just adding some lubrication. It sounds like you'd be better off pulling it apart for a proper cleaning and putting it back together with a fresh bit of grease and light machine oil.

Otherwise, you'll never get all of the solvent out of the chuck. I'd expect it to start rusting in places internally that will make things worse.

If you have a bench vise, and a wood, lead, or rubber mallet, and can make a ring to press things apart (out of wood or a piece of pipe), you've got everything you need to press the chuck apart, clean it up and lube it, and put it back together.

You can google "rebuilding a jacobs chuck" or look at the following links for directions.

https://www.youtube.com/watch?v=nLYWZXfMIYM
http://wiki.vintagemachinery.org/JacobsChuckRebuild.ashx
http://owwm.org/viewtopic.php?t=49218

You do not need an arbor press to do this. I press mine apart with my bench vise or mallot taps with a wooden dowel or block between the mallot and the chuck. Also, it doesn't sound like your chuck is old enough to need new jaws or a split nut - just cleaning and reinstalling the existing ones will probably be enough. If not, depending on the chuck you have, it may be less expensive to simply replace the entire thing than to get a jaws/split nut kit to rebuild it.

It's not rocket science. I was intimidated and avoided doing this until a couple of years ago. Once i did it and realized how easy and effective it is, i don't hesitate to just do it right the first time now. Once you get it apart, you might find a burr or some corrosion that you can clean up with a fine file, a wire wheel, or some wet/dry fine sand paper. Something is causing it to bind up a bit. Maybe all it needs is a thorough cleaning.

Good luck with it.

paulh
 
If i had put that much solvent into a chuck, i wouldn't be comfortable just adding some lubrication. It sounds like you'd be better off pulling it apart for a proper cleaning and putting it back together with a fresh bit of grease and light machine oil.

Otherwise, you'll never get all of the solvent out of the chuck. I'd expect it to start rusting in places internally that will make things worse.

If you have a bench vise, and a wood, lead, or rubber mallet, and can make a ring to press things apart (out of wood or a piece of pipe), you've got everything you need to press the chuck apart, clean it up and lube it, and put it back together.

You can google "rebuilding a jacobs chuck" or look at the following links for directions.

https://www.youtube.com/watch?v=nLYWZXfMIYM
http://wiki.vintagemachinery.org/JacobsChuckRebuild.ashx
http://owwm.org/viewtopic.php?t=49218

You do not need an arbor press to do this. I press mine apart with my bench vise or mallot taps with a wooden dowel or block between the mallot and the chuck. Also, it doesn't sound like your chuck is old enough to need new jaws or a split nut - just cleaning and reinstalling the existing ones will probably be enough. If not, depending on the chuck you have, it may be less expensive to simply replace the entire thing than to get a jaws/split nut kit to rebuild it.

It's not rocket science. I was intimidated and avoided doing this until a couple of years ago. Once i did it and realized how easy and effective it is, i don't hesitate to just do it right the first time now. Once you get it apart, you might find a burr or some corrosion that you can clean up with a fine file, a wire wheel, or some wet/dry fine sand paper. Something is causing it to bind up a bit. Maybe all it needs is a thorough cleaning.

Good luck with it.

paulh
Just a caution on clicking on the links shown above. I couldn't get out of it while waiting an infinite amount of time for it to load which it never did. Ctre, Alt, Del. needed to get out of it!
 
Thanks guys.

The chuck is still working fine. However, you have me questioning the future. Time is an extremely precious commodity, however time to take the chuck apart sounds like something I should do. This makes me think of the story about the guy that worked on the potato line at the packing house.

He quit his job one day. The foreman asked him why he quit. "All you have to do is pick out the bad potatoes and toss them into the reject barrel. What is the problem?" The worker replied, "It is all of those decisions, they are killing me."

Enjoy and thanks again,
JimB
 
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