Drill chuck not staying locked.

[BobCoates1953]

My son has a 10er and called to inform me that what I gave him was a piece of junk. end quote ha
Ok,he was using the drill press with a 7/8" bit and it would not stay tight in the chuck. He says he had in aligned with flats and got it as tight as he could but it still would come loose. He is on a good day 8-9 hrs away.
When I called back, he said he had it on high speed, but the bit was jammed and he was not going to do anything more.
Could the gear ring and teeth on the jaws be a problem?
Ideas?

Bob

[reible]

You need to round robin method using the three holes in the chuck and tighten progressively.

Drill speed depends on bit type, size and material being drilled. Fast is not always better! Find a chart and pick a speed close to the recommendation.

Ed

[jsburger]

My son has a 10er and called to inform me that what I gave him was a piece of junk. end quote ha
Ok,he was using the drill press with a 7/8" bit and it would not stay tight in the chuck. He says he had in aligned with flats and got it as tight as he could but it still would come loose. He is on a good day 8-9 hrs away.
When I called back, he said he had it on high speed, but the bit was jammed and he was not going to do anything more.
Could the gear ring and teeth on the jaws be a problem?
Ideas?

Bob

High speed on a 10ER without a speed changer is 3450RPM. That is way way too high for a 7/8" bit. Speed varies depending on the type of bit and type of wood. For twist drills the speeds are 500RPM to 750RPM.

Here is a link to Wood Magazines drill speed chart.

https://images.meredith.com/wood/images ... dchart.pdf

[BobCoates1953]

How to tell if jaws/gears are bad. Can the shopsmith be taken apart to check?

[rpd]

How to tell if jaws/gears are bad. Can the shopsmith be taken apart to check?

There is a good thread on rebuilding drill chucks.

https://www.shopsmith.com/ss_forum/main ... t4262.html

Also follow the links in the posts.

[chapmanruss]

If the Drill Chuck has been rusted in years past then "de-rusted" and cleaned up it could have internal damage to the jaw teeth or the threads in the ring. Only opening it up will revel if is has rust pitting or other damage to the chuck. If you cannot open it up check to see if the jaws are loose in the chuck at any point between fully open and closed. If so it is likely damaged. The teeth in the jaws should be tight with the threads in the split ring.

[BobCoates1953]

Thanks for input, will pass info to my son and investigate when I see him again. Probably not until spring.

[cham-ed]

If it is the Jacobs chuck (used on a lot of 10ERs) there is a rebuild kit available from Jacobs. the chuck is a variation of their #33 if I remember right.
And did you say a 7/8 drill, that is way over capacity for these chucks. So no wonder it is jammed.