Improve 3 jaw chuck runout
ฝัง
- เผยแพร่เมื่อ 8 ก.พ. 2025
- Fixing your lathe's 3-Jaw chuck is a very easy procedure. You only need a dial indicator, a test bar and a rubber mallet.
If you like my videos please subscribe and visit my blog machinistnick....
PS. As a test bar I used a chrome plated hardeneed steel shaft used for linear bearings.
Thank you so much this will go a long way in helping me finish my report and also thanks for making it short and straight to the point
I just noticed something when you check it the second time your dial indicators read up next to the Chuck that's the only reason why it's better
Hello, The method I am showing it is not a trick. The reason I moved the indicator close is to able to keep both indicator and chuck to a close view inside the camera's view area.
@@machinistnick I don't care what reason you moved it. But I guarantee the run out 3 in in towards the Chuck is going to be a hell of a lot less than 3 in out LOL there's just no getting around that
@@machinistnick lol. Move the camera then not the indicator!!! It is absolutely erronious to compare 4 inches from the jaws to .5 inches from the jaws after making a so called adjustment.!! Who do you think is stupid enough to believe that you HAD TO move the indicator into the cameras fieldif view lol
Come on man
@@ClownWhisper Hello, I am not cheating and of course I am not trying to sell something here. The shaft is Φ10, CF53 chrome plated hardened steel with H7 precision.
As you can see I have the indicator on the carriage. By moving the carriage I can check both ends. And the distance is not 0.5" is more than 30mm
You need to hit it much harder with a bigger steel sledgehammer and then move the dial indicator slightly off the test piece and it will show ZERO runout!
WHAT DAMAGE !! ARE YOU ! INCURRING !?
@@davidwillard7334 😎 Sarcasm is sometimes hard to convey in the comments section.
@@Billydevito IT'S BECAUSE !! ITS !! TRUTHFUL !!!
Thank you I tried it on my Chinese mini lathe and it did improve it. Changing the 2 spindle ball bearings to angular contact ball bearings or taper roller bearings improves the run out.
Changing the bearings with angular contact is the best you can do on the mini lathe :)
Why close comment critique is what make us grow and learn.
By mistake I marked a few of my videos as "Made for kids", so the comments were disabled. I turned them on now
@@machinistnick by the by how precise was the mill drill
@@woozhi9218 ??
@@machinistnick meaning was thè milling machine precise sorryif im not clear
@@woozhi9218 There is no Milling machine on the video.. If you are asking about the lathe then yes, it has good precision
Thank you, I'm having that problem now hopefully it works. Great job 👍
Had to do the same thing on a 5" chuck that replaced the factory 3" . This isnt supposed to fix a bad chuck ,its just an adjustment .
That Chuck has a boss on the back plate! Tapping it is going to do absolutely nothing. It's a Chinese lathe this is what you get it's not going to be repeatable even if you manage to knock the piss out of it and get something lined up for a few minutes it's going to go back to being out
So he is just trying to move solid part thru solid part?
Depends on how much tolerance there is between the back plate and the chuck. If you can change the runout by tapping the chuck with the bolts loosened then it's not a tight fit.
This machine is made in China and not in Switzerland. There is great tolerance between the chuck rear pocket and the backplate boss.
This tolerance is also good because makes this thing adjustable. Remember: If you cannot make it perfect, then make it adjustable!
Noticed you moved your indicator closer to the chuck as applied to the end of the rod where you originally started,,was there a reason why you did that?
If you must strike a mounted chuck - esp. laterally - be very cautious not to Brinell the nearest headstock bearing races.
My mini lathe has a huge runout at the jaw. Must finish the work in one round. Cannot take it out and re-chuck it. The runout is approximately 0.15-0.20 mm
same here too can even work with it if u find any solutions pls send me msg
This method is not enough correct - you must use 2 dial indicators - on the 2 ends of the rod.
There is no need for 2 indicators. I use one on the lathe carriage. With that way I can measure both ends.
PS. I didn't show that on the video and as you can see many viewers things that I am cheating. I am not cheating, I just made the video shorter.
The indicator was closer to the chuck after your fiddling!
I moved it..
@@machinistnick what he saying is the test the Improvement isn't valid because it's now moved way up to the Jaws
Exactly
interesting can you do a runout on a round rod to put set screws and also a center hole for a motor shaft that goes in the round rod and tightened with two set screws, love to see a video of that please, thank you.
When you retighten the nuts, won't it go back to the original run out? Do you just leave them in the loosened position?
EXACTLY ! WHAT HAPPENS !!
@@davidwillard7334 Yes. I found the high side and shimmed it with very thin slices of clear plastic and retightened. Took a few times but now my dial indicator doesn't move AT ALL! Less than 0.0005" of run out.
@@VW421 that's also how i did..i placed a 0.05mm shim between the backplate and the chuck to get it to be somewhat true atleast
The last measurement is with the nuts tighten.
does this mean you have to re-alignment your tailstock everytime you reinstall your chuck?
I use to align the tailstock to the headstock spindle bore. That way is always better.
Runout ?
My stock WOBBLES LIKE HELL.
I can see it with my eyes without the gauge.
Why is that ?
Hi Nick just wondering why you moved the dial indicator closer to the chuck? Of corse there is less run out the closer to the chuck, do it again with out moving it.
Hello, I moved it just to make it fit on the camera for the close shot. Do not worry, it is not a trick. I am not making any money from selling the lathe :)
Nick, I am old a bit new to this and dumb, I have a screw-on chuck on my mini lathe,
what can I do, please. Colin.
I never had a lathe with a screw on chuck so I am not sure about what to tell you...
Thank you! Gr eat!
I would assume if you keep at it you can get to 0.001mm?
On a quality Swiss made lathe yes.
Thanks for the video! Do you know where to get a test bar? Can't find it on aliexpress as well. Thanks
Where you can get the test bar? And how i can be sure that test bar is really good one?
I would like to do same test.
Search on ebay or buy a Φ20mm shaft for linear bearings.
It is MT2. Most mini lathes have MT2.
Google "MT2 morse taper schematic" and you will find out dimensions
You are better off numbering the mounting studs...rotating the chuck to get the best location, and if it isn't good enough...get close and align bore the chuck jaws til it is! G>
Ага, а теперь попробуй наново зажать цилиндр и обратно увидишь такое же биение.)) Для того чтобы увеличить точность, нужно протачивать кулачки патрона.
Китайский трёхкулачковый патрон это вообще не про точность.
Лучше обзавестись четырёхкулачковым и цанговым.
yes, but what happens if you remove the stock from the chuck, then re-chuck it and measure again.........still a 0.01 run-out
Well... It is a 3 jaw chuck so everything depends mostly on the chuck quality.
If the chuck is good quality and in good condition then the second time you put the stock in the runout might be from 0.005 to 0.05.
Make a collet or the Americans call it a bushing. Can get really accurate and repeatable results then. Plenty of video instructions on u-tube
I actually have an ER40 collet chuck on my big lathe. Collet chucks is what I use for precision.
what is that dial called
Hello, It is a dial indicator
Machinist Nick what are the specifications of that dial indicator
It is a simple dial indicator with a resolution of 0.01mm
I’m not saying you’re wrong, but you don’t show the whole video, and you moved the dial much closer to the chuck... so it’s not really proving much..
The NEXT !! YOU TUBE !! VIDEO !! I'LL JUST !! REMOVE !! ALL THE !! BOLTS !! AND THE CHUCK'S !! RUNNING !! AS !! TRUE !!! AS !!!
I don't believe your findings. The chuck does not have that much play on the step flange. I think your measurement points are not satisfactory, and are giving you inaccurate data.
Sorry.
Um... No.
😘
So, (and I know this is a few years old now) how many people did this injure? You will be running a mini lathe with a near 3-pound chuck and loose bolts at potentially 25,000 rpm with unlisted side loads!
Also, did you know that just moving the dial indicator closer to the chuck (as in the video) will create the illusion of the runout being fixed or at least lessened?
If you are going to bother to post how-to videos on youtube at least go through everything you do in a bit of detail, maybe like packing and tightening the bolts after you are done, you did tighten the bolts didn't you? *shudder*
Damn didn't know these things ran at 25000 RPM. That's almost twice as fast as an F1 engine...
One has to assume he tightened the nuts after what is called "bump truing", which is a fairly common practice.
And before you whinge about his teaching, shouldn't you check your own facts 25 K from one of those lathes, really?