How to fix runout in a drill chuck

[@dfgdfg_]

Now I just need to buy a $3000 lathe to fix my $100 drill 😂

[@Choober65]

The moment i saw what you were doing i knew how you were addressing the problem and fixing it. EXCELLENT video.

[@Critical_Stinking]

I'm buying a lathe. They're so versatile, only limited by imagination of the user. Brilliant video, thank you.

[@xmachine7003]

Excellent!

[@J.T.19134]

Buy me one also....PLEASE. Thanks

[@andre1987eph]

You better not dare sell this man a wobbly drill! 🤣

[@kinoshita8133]

Thank you for actually showing how to FIX instead of just diagnose and replace! 😂

[@MagnetTricks]

That was captivating. Didn't expect to get so entertained by a drill chuck fix video :)

[@ellieprice3396]

Good video. You could also bore the jaws with a small carbide boring bar.

[@Godzilla2k69]

You taught me something. Thank you

[@iacoposimonelli7191]

You are welcome, Joe. If needed, some more details in my answer to Anto.

[@johnmc9362]

The time and effort to make one component of your production process function precisely as you want it to explain why you tops behave so beautifully. No effort or time is spared in their creation.

[@iacoposimonelli7191]

This is true, in fact it takes much time to make tops in the way I do.

[@samrodian919]

There is one serious flaw with your methodology. Using the diamond ball means the very end of the jaws are not reground. Therefore putting drill bits to the bottom of the chuck will result in the bit will only be touching and gripped by the UNground portion of the jaws ending up with the situation of the runout being worse than before. The solution is to use a parallel diamond impregnated bit in the lathe chuck ensuring the jaws are ground right down to the end and then they will grip any drill bits concentrically with no radial run out.

[@iacoposimonelli7191]

I see your point, but I didn't have this kind of problem, because in my chuck there is an empty space between the jaws and the bottom of the chuck, which was sufficient for the jaws to be reground in their full length, even using the shown ball diamond bit. If someone tried this method and had the problem you say, I agree that it is better to use a bit with a different shape, and not a ball, (or maybe even just a littler ball), until he can be sure to have the jaws reground in their full length.

[@298VJLJS]

That's a brilliant process ! I have tried couple times but I got some questions when I tried to recreate how you did it. 1. As long as my ball bits touch the chuck it starts to shake itself, I review many times of your process but didn't find out this problem. 2. Why is that you make a mark on the chuck ? (the black point) 3. How do you measure the lathe and the chuck's center point is totally at the same line since it's an old lathe without computer's help to measure it. Sorry for asking so many questions due to I'm still learning how to operate the old lathe that I have in my garage.

[@iacoposimonelli7191]

Thank you! I try to answer: 1. The ball bits vibrate when touching the chuck? It doesn't seem normal. Maybe the ball bits you use have a too thin and delicate stem? It's difficult for me to say, without to see with my eyes. 2. This isn't important. The black dot was just for to mark the direction of tilting of the rod mounted in the defective chuck, but I think that you could avoid to mark it. 3. The important thing is that you make the defective chuck axis and the lathe chuck axis parallel, in the way I described in the beginning of the video. I too don't use computer's help. Parallel and centered are two different things. Centering has not to be accurate; just mount the tool with the defective chuck on the tool post, (or directly on the cross slide, I don't know what works better for you), of your lathe, at approximately the correct height. If the ball bit can enter into the defective chuck without touching its jaws, the centering is accurate enough, and you don't need measuring tools for centering. You can simply mount a short piece of rod in your lathe chuck, then you mount the free end of that short rod in the defective chuck, so the two chucks will be automatically aligned and centered with sufficient precision, (but parallelism has to be checked and corrected in any case, in the way I showed).Then with your ingenuity you will have to find a way to attach the tool with the defective chuck to the tool post or cross slide of your lathe. Then you remove the short rod from the two chucks, correct the parallelism, mount the diamond ball tip in the lathe chuck, and go on.

[@Z-Ack]

Well now its straight but wont hold onto anything under any torque.. thats the reason i toss out my chucks because they wont bite onto any round bits.. have to use the bits with a flat in em and those are notorious for having the wobble where you cant get em in a chuck quick and right...

[@iacoposimonelli7191]

I don't have this problem. The grip of the jaws on the bits seems as good as before the reboring, and I use only round bits, not the ones with flats in them. After more than two years from this repair the chuck still works well, and I am happy I repaired it in the way I showed here, because this was a fast, effective and inexpensive repair. I use this air drill for making holes in brass pieces mainly, and I never had the problem of the bits slipping between the jaws of the drill. Also read my answer to Anto Markic.

[@J.T.19134]

Would it not be better to use a V or inverted V Shaped diamond bit. A round bit will hit at say 1/32nd, then you have insert in 1/128" deeper, n repeat, n repeat, n repeat until at the end of a 1/2" chuck??

[@iacoposimonelli7191]

I am not sure to understand your reasoning, I had no problems using the ball diamond bit. But there is one thing that I didn't explain in the video; when the jaws of the chuck were clamped with the three alumimum pieces in between, the space between the jaws was larger than the ball bit itself, so that the ball bit could enter between the jaws without even touching them. At that point, with both the lathe and the air grinder turned on, I moved slowly the cross slide, until I could hear that the ball bit was barely starting to grind the jaws. Then I moved the saddle back and forth for to grind the jaws for all their length. The ball bit was not a problem because there is some empty space in the chuck behind the jaws, so the ball bit could enter deep enough and grind the jaws in their full length before the ball bit hitting the bottom of the chuck. I removed only a few undredths mm from the jaws. The chuck could still hold even the littlest bits after all of this.

[@J.T.19134]

@@iacoposimonelli7191 I guess I thought all Chucks were made like the Cheap drill I had, don't wanna throw anyone under the bus tho(Ryobi). The Jaws come out of the chuck on an angle, so I was thinking a V shaped diamond bit would work better, but I went to my Press, and Noticed if you put pieces in between each Jaw, and keep them set back a little, making then set more in a straight line. Ill try it on a Old chuck. I bout 10 Drills for $10 at a Yard sale. So I have a bunch of Chucks. They can be used for MANY things.

[@AlainHubert]

Won't the chuck jaws be unable to hold smaller drill bits now ?

[@iacoposimonelli7191]

The thickness of the metal to remove from the jaws is very little, a few hundredths mm, so, if this is done carefully, the chuck will still hold even the smallest bits after the reboring.

[@J.T.19134]

It didn't look like a few hundredth of mm when you wiggled it. JS

[@dustymerrl5154]

although way more difficult and “expensive” time consuming I will replace the chuck for a whooping $20 on Amazon, if I make $80 a hour would be 15 minutes of my working time. I know it is a bad move considering that I could spent the whole day + cost of whatever $10k machine I need to buy

[@iacoposimonelli7191]

If I made $80 a hour, I would buy more expensive tools which supposedly should not have problems like this.

[@Bigshoots86]

Yeah, after two weeks of owning them, my Dewalt XRs are getting sent back, they wobble like crazy and make me look like an idiot. Adios Dewalt!

[@xmachine7003]

Are the older corded ones better?

[@antomarkic7190]

Who is the manufacturer of that diamond ball. This way these can be cheap or damaged chuck fix. Can You explain in more detail how you fit the diamond ball and chuck . Thank you so much for the video!

[@iacoposimonelli7191]

Sorry, Anto, I see only now you question. I don't remember now the manufacturer but this is not important, whatever diamond ball bit will work fine. It is very important that you mount the tool to be fixed to the slide with its rotation axis parallel to the trails of the lathe, as much accurate as possible: otherwise, the grinded surfaces of the jaws will be not precisely parallel each other, as they should be. The height of the rotation axes of the chuck to be fixed and of the diamond bit has to be the same. The three aluminum pieces must have precise constant thickness, (long sides parallel), and exactly the same thickness in the three pieces. I didn't explain this in the video, but the diamond ball should be littler than the hole in the chuck with the alumimum pieces inserted; so that it should be possible for the diamond ball to enter into the hole of the chuck with aluminum pieces without touching the jaws. When you are ready to start reboring, turn on both the lathe and the tool with the chuck to be fixed. Move the cross slide so to center the chuck to be fixed to the diamond bit, and let the ball diamond enter into the hole of the chuck without touching its jaws. Move very slowly the cross slide, (doing so the axes of the chuck to be restored and of the diamond bit will become misaligned but this is ok, the important thing, as said, is that the two axes stay parallel), until you hear it barely to start grinding, at that point stop moving the cross slide. Grind all the length of the jaws. Look at the grinded jaws; if only one or two jaws, or part of them, have been grinded, you have to repeat grinding to remove a bit more metal from the jaws. When you see that all the three jaws have been grinded, in their full length, you are done. Doing so allows you to remove the littlest amount of metal from the jaws, so that the restored chuck will still be able to hold even the littlest bits.

[@DailyFrankPeter]

Is this a faulty chuck or can this also be caused by the drill itself (it should be a lot easier and cheaper to send off just the chuck than the whole thing)?

[@iacoposimonelli7191]

I am not sure where was the problem. I never separated the chuck from the tool so I couldn't check the tool shaft. I believe that more probably it was the chuck, because this is a quite cheap chuck. At a certain point I was tempted to separate the chuck from the tool and, in case, to buy a good quality chuck for it. But in the end I preferred to rebore the jaws.

[@dreamlessfull]

while grinding, I see that also the chuck barrel is untrue

[@iacoposimonelli7191]

The outer part of the chuck nearer to the air grinder wobbles a lot, (is that the "barrel"?). That part is a bit loose, and quite off centered relatively to the rest of the chuck itself. After four years I am still using this air grinder, it's a good tool, but its chuck is garbage. Some of its teeth got broken while tightening the tips, with no strong pressure.

[@bensevrywere]

Any way to recreate this with cheap shit?

[@iacoposimonelli7191]

If you don't have the possibility to use a lathe, I think it would be difficult to fix the chuck. The best option in this case is probably to buy a new chuck.

[@bensevrywere]

Iacopo Simonelli turns out the whole Chuck is wobbly not the jaws, could you part some knowledge on that?

[@iacoposimonelli7191]

@@bensevrywere , it was the same for me, the whole chuck wobbled, and the jaws with it. But the chuck wobble by itself is not so important, the mine still wobbles, I didn't make anything to correct this. I only rebored the jaws as shown in the video and now the centering is decent.

[@dancalinfota6157]

the angles of the "after" part are fishy....can't really compare them if you blur the meter at the end and also not show the movement of the entire drill bit. Was this a failed experiment but you decided to blur the end and pretend it was better when it was not?

[@iacoposimonelli7191]

I showed the wobble before and after the reboring, and if you look at the video with some more attention, you will see that the wobble has almost disappeared.

[@DaniloKalinisan-f6o]

Just to fix the problem you used too many expensive tools. Make it easy and simple.