User Panel
User Panel
User Panel
|
Posted: 2/26/2022 9:35:14 PM EDT
[#1]
If the back plate fits into the chuck far enough, you may be able to remove the chuck and turn the OD of the back plate smaller and add 4 set screws to the chuck that you could use to help center the chuck when you indicate it in.
|
|
|
|
Posted: 2/26/2022 9:37:53 PM EDT
[#2]
Quote HistoryQuoted: If the back plate fits into the chuck far enough, you may be able to remove the chuck and turn the OD of the back plate smaller and add 4 set screws to the chuck that you could use to help center the chuck when you indicate it in. |
|
|
|
Posted: 2/27/2022 6:02:28 AM EDT
[#3]
So the chuck body isn't concentric with the spindle axis? What does your indicator say on that?
|
|
|
|
Posted: 2/27/2022 7:56:49 AM EDT
[#4]
Quote HistoryQuoted: So the chuck body isn't concentric with the spindle axis? What does your indicator say on that? |
|
|
|
Posted: 2/27/2022 9:04:23 AM EDT
[#5]
Is it run out or not concentric/coaxial?
The fix for each of those is different. |
|
|
|
Posted: 2/27/2022 9:37:50 AM EDT
[#6]
Quote HistoryQuoted: Is it run out or not concentric/coaxial? The fix for each of those is different. |
|
|
|
Posted: 2/28/2022 12:00:27 PM EDT
[#7]
As a rule of thumb it is a good idea to true the back plate to the machine, most are oversized a bit to allow for that. Just mount the back plate and take a light cut to bring it to size then attach it to the chuck. You may still be able to do that without starting over with a new backplate, depends on how much it is out.
|
|
|
|
Posted: 2/28/2022 12:16:10 PM EDT
[#8]
Quote HistoryQuoted: As a rule of thumb it is a good idea to true the back plate to the machine, most are oversized a bit to allow for that. Just mount the back plate and take a light cut to bring it to size then attach it to the chuck. You may still be able to do that without starting over with a new backplate, depends on how much it is out.  HOW TO MAKE YOUR CHUCK SUPER PRECISE BY ADAPTING IT INTO SET-TRU |
|
|
|
Posted: 2/28/2022 3:58:08 PM EDT
[#9]
Quote HistoryQuoted: Thanks so much. I just watched this video and plan to take it all apart and inspect and will do just as you said. The set screws seem easy enough and I have a rotary so planned that for good measure. This thing is not super heavy but hard enough to get started threading holding it up. I got one of my axis' on the DRO installed yesterday and the VFD the day before that. So finally close to getting up and going. I still have to put the tailstock back on and align it.  https://www.youtube.com/watch?v=Ts_cUeo9QjUQuote HistoryQuoted: Quoted: As a rule of thumb it is a good idea to true the back plate to the machine, most are oversized a bit to allow for that. Just mount the back plate and take a light cut to bring it to size then attach it to the chuck. You may still be able to do that without starting over with a new backplate, depends on how much it is out. https://www.youtube.com/watch?v=Ts_cUeo9QjUEven if you don't do the set screws for fine tuning, turning the back plate as shown about the 10:00 minute mark is highly recommended. There is probably enough material on it you could create a new hub for the chuck to locate on if it is out of true. |
|
|
|
Posted: 3/4/2022 6:19:05 PM EDT
[#10]
I spent over an hour trying to separate the back plate from the chuck to no avail.
The runout on the chuck body is .008 and the back plate is .006 so I'm sure that is the issue. I just indicated on a gauge pin and was able to get it to zero out so I guess I live with it until I get a torch and run out of cares lol. I have been eyeballing an import 6 jaw 8" with plate for just under $300 so thinking about that. I used this drift until I mushroomed both sides and just turned it down to fix it for grins. I also lined up the tailstock.  Attached File |
|
|
|
Posted: 3/4/2022 6:53:53 PM EDT
[#11]
You're worried about a collective .014" TIR on a 4-jaw?
|
|
|
|
Posted: 3/4/2022 6:58:42 PM EDT
[#12]
Quote HistoryQuoted: You're worried about a collective .014" TIR on a 4-jaw? |
|
|
|
Posted: 3/4/2022 8:15:12 PM EDT
[#13]
Quote HistoryQuoted: I spent over an hour trying to separate the back plate from the chuck to no avail……………….. I used this drift until I mushroomed both sides Are you sure you had all the bolts out? Something doesn’t sound right. |
|
|
|
Posted: 3/4/2022 8:16:34 PM EDT
[#14]
Quote HistoryQuoted: Are you sure you had all the bolts out? Something doesn't sound right. |
|
|
|
Posted: 3/5/2022 7:24:27 PM EDT
[#15]
Ya, that TIR is fine, IMO.
You can also try indexing the back plate into different orientations to reduce runout. I do this for all my chucks. It's not fancy, just some T&E. A hash mark on the spindle matched to a mark on the chuck to make sure they go back together in the best possible arrangement. It would also be helpful for you to post pics of what you're actually working on. It may be an integral chuck, with no removable mount option. That's how my 4j chucks have been. |
|
|
|
Posted: 3/5/2022 10:47:34 PM EDT
[#16]
Quote HistoryQuoted: Ya, that TIR is fine, IMO. You can also try indexing the back plate into different orientations to reduce runout. I do this for all my chucks. It's not fancy, just some T&E. A hash mark on the spindle matched to a mark on the chuck to make sure they go back together in the best possible arrangement. It would also be helpful for you to post pics of what you're actually working on. It may be an integral chuck, with no removable mount option. That's how my 4j chucks have been. |
|
|
|
Posted: 3/6/2022 12:21:01 AM EDT
[#17]
|
|
|
|
Posted: 3/6/2022 9:16:00 AM EDT
[#18]
To me it appears you could remove the chuck from the back plate, as you suspected.
If I was going to do something, and I probably wouldn't, here's what I'd do. Secure the back plate and chuck on the spindle, then separate the two leaving the back plate in situ. Face the backplate and skim the OD to bring it true. Reinstall the chuck with the 4 screws snug. Bump it around with delicate blows until it indicates the lowest TIR your patience will permit. Lock it down tight. |
|
|
|
Posted: 3/6/2022 2:08:54 PM EDT
[#19]
Quote HistoryQuoted: To me it appears you could remove the chuck from the back plate, as you suspected. If I was going to do something, and I probably wouldn't, here's what I'd do. Secure the back plate and chuck on the spindle, then separate the two leaving the back plate in situ. Face the backplate and skim the OD to bring it true. Reinstall the chuck with the 4 screws snug. Bump it around with delicate blows until it indicates the lowest TIR your patience will permit. Lock it down tight. I appreciate all the input y'all. |
|
|
|
Posted: 3/7/2022 10:58:23 AM EDT
[#20]
Quote HistoryThat is definitely a flat back chuck. Did you try loosening the bolts a few turns and tapping on the heads? You would need the chuck off the lathe to do that, obviously. Probably some oil or coolant seeped in and dried into a residue that is holding the parts together. |
|
|
|
Posted: 3/7/2022 11:24:59 AM EDT
[#21]
Quote HistoryQuoted: That is definitely a flat back chuck. Did you try loosening the bolts a few turns and tapping on the heads? You would need the chuck off the lathe to do that, obviously. Probably some oil or coolant seeped in and dried into a residue that is holding the parts together. |
|
|
|
Posted: 3/7/2022 3:50:38 PM EDT
[#22]
Quote HistoryQuoted: You are a freaking genius or I am a dummy one lol. I did not think of that. I have plenty of spare bolts so I will try that. Thank you! Quote HistoryQuoted: Quoted: That is definitely a flat back chuck. Did you try loosening the bolts a few turns and tapping on the heads? You would need the chuck off the lathe to do that, obviously. Probably some oil or coolant seeped in and dried into a residue that is holding the parts together. We can skip the labels and just call it experience. Hope it works! |
|
|
|
Posted: 3/12/2022 12:58:04 AM EDT
[#23]
I found the issue lol. The backplate and the chuck was threaded. The spindle is long. As soon as I removed it from the lathe it just fell off.
I cleaned it up and put it back together. I found there was no lip, not sure if that matters. I need experience on this so I ordered an unmachined back plate to fit it. And holy cow that cast iron goes everywhere.  Attached File |
|
|
|
Posted: 3/12/2022 9:42:05 AM EDT
[#24]
Yes it does! Thoroughly clean your machine afterward.
|
|
|
Win a FREE Membership!
Sign up for the ARFCOM weekly newsletter and be entered to win a free ARFCOM membership. One new winner* is announced every week!
You will receive an email every Friday morning featuring the latest chatter from the hottest topics, breaking news surrounding legislation, as well as exclusive deals only available to ARFCOM email subscribers.
AR15.COM is the world's largest firearm community and is a gathering place for firearm enthusiasts of all types.
From hunters and military members, to competition shooters and general firearm enthusiasts, we welcome anyone who values and respects the way of the firearm.
Subscribe to our monthly Newsletter to receive firearm news, product discounts from your favorite Industry Partners, and more.
Copyright © 1996-2024 AR15.COM LLC. All Rights Reserved.
Any use of this content without express written consent is prohibited.
AR15.Com reserves the right to overwrite or replace any affiliate, commercial, or monetizable links, posted by users, with our own.
Attached File
Attached File