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October 21, 2014 at 1:45 pm #49277
Ok you metal guru’s I need some info. I am rebuilding a clock that it going to require bushings in the barrels. No problem can be done fairly easily. My question is when bushing these barrel caps and barrels would a 4 jaw chuck make it easier or should I just stick with a 3 jaw? This would be for my Taig and I am looking at buying a chuck with step jaws which my Taig chuck doesn’t have. Just curious as to your thoughts.October 21, 2014 at 2:29 pm #59942
A 3 jaw chuck will never be as accurate as a 4 jaw chuck because of the way it is made. Number 1 jaw will always run ahead of number 2 and 2 will run ahead of 3, meaning that they will never close concentrically i.e., there will always be a runout of a few thousandths. With a 4 jaw you can always dial it in to zero because each jaw adjusts/runs independantly from the other three jaws.
Most guys find them to be more of a PITA to zero but, by using two chuck keys on opposite ends of the chuck and a cheap dial indicator, zeroing can be done in almost no time at all.
Hope this helps,
RenOctober 21, 2014 at 3:40 pm #59943
So Ren then I am guessing that a 4 jaw chuck with self centering jaws will have the same problem as the self centering 3 jaw?October 21, 2014 at 4:01 pm #59944khoward279Participant
If you can find a 3 jaw that’s adjustable it works as good as a 4 jaw. They cost a little more but worth it/
. I use this style about every day and the concentricity is with in .0005 not bad. Good luck with your project.October 21, 2014 at 4:02 pm #59945
I’ve never seen a self centering 4 jaw but, if it is self centering, I would tend to believe it would have to run on the same priciple as a three jaw chuck. besides that, I would still prefer being able to zero by hand and be sure of total control over the material.
RenOctober 21, 2014 at 5:04 pm #59946
Bernie, both Ren & Kevin are correct BUT but but but 😆
There are 4 jaw independent chucks but like their three jaw cousins, the accuracy is only as good as the manufacture, so a REEEALLLLY good 3 jaw chuck that will cost you $$ will have a bare minimum of inaccuracy. I know our guys use very good 3 jaw chucks in the big lathes, and they still have to dial the work in.
I’m not sure of the size of your lathe but as Ren says, a 4 jaw chuck gives you much more control over your run-out, but, again, you need a good dial indicator, better two, and mag bases. A 4 jaw independent will also allow you to hold a piece where the part to be machined is off center, you can adjust each jaw to center an offset hole in a plate, for example.
That being said, you can always rough align it with the tailstock before using the dials, you can get very close to zero with that method, depending how much play is in your lathe etc etc
Personally, I would go for the 4 jaw, the best that the budget of the last quarter of 2014 can allow, it will work well and your great, great grand kids will be really happy you did, because they will use it
Just my two bits..October 21, 2014 at 5:56 pm #59947
Thanks again to all. Chris I was looking for something fairly simple in a metal chuck as I am going to use it on my Taig lathe. I don’t want to break the bank at my age but didn’t want cheap either. I will check into dial indicators but I know they are not cheap either. I know on my Taig with a point in the headstock and the tailstock the alignment is dead on. The last cap I did I used the point in my tailstock into the hole of the cap then clamped it down with the chuck I borrowed. It came out really well and has been working now for over a year. I did check the barrel and 2nd wheel with my depthing tool. It came out pretty accurately.
Ok so now I guess I start looking at dial indicators and new chuck. Chris I told my wife it is your fault that I need to spend our retirement nest egg. Been married to her for 47 yrs and if I were you I would be finding a fox hole my friend. 😆 😆 She is a mean one when she is upset. I only upset her once in 47 yrs. 😆October 21, 2014 at 6:25 pm #59948
yeah yeah Bernie, blame the guy that’s 8k clicks away 😆 I understand though, I used a few of you all as an excuse for the mill expenditure 🙄
Damn handy these forumsOctober 21, 2014 at 6:31 pm #59949
Bernie, watch the first few minutes of this… https://www.youtube.com/watch?v=vTQT6PwgJTA
Buddy on the drill isn’t to concerned with alignment, he’s drilling all the plate holes free hand and in a Bunn Special plate 😆October 21, 2014 at 6:50 pm #59950
Well had to come up with somehting. Figured you’d be safe. 😆 😆 Will watch the video.October 21, 2014 at 7:05 pm #59951
That is a great video Chris!
BobOctober 21, 2014 at 8:08 pm #59941
Bernie, Bernie, Bernie, save your money on that dial indicator…..Harbor Freight……dude!!!!
Go here: http://www.taigtools.com/c1030.html for the 4 jaw chuck and here: http://www.harborfreight.com/1-inch-travel-machinists-dial-indicator-623.html for the indicator.
What you’re looking for when indicating your material is to have no movement of the needle as you spin the material in the chuck. You don’t need a Starrett indicator. Watch this video:
I regularly have to maintain tighter than .0005″ tolerances when making metal ferrules for my bamboo fly rods or pistons for low temp sterling model engines. 4 Jaws can be as accurate as any collet if you have enough practice and patience.
RenOctober 21, 2014 at 9:04 pm #59954
Not too sure about the accuracy of the Taig 3 jaw but if it’s anything like the Sherline then it’s more than adequate for staying within tolerances for boring clock barrels and caps. Four jaw is nice to have, especially if you would like to do some offset work but not necessary for the job you’re going to do. If you’re going to buy a chuck anyway so that you’ll have step jaws and you think you’ll have a need for a 4 jaw then now’s the time!
I don’t remember if you told me whether you had a mill or not but if you do it’s pretty easy to make some soft jaws for your existing chuck in which you can then either bore or turn your steps depending on whether you’re after concave or convex clamping. In fact I would think that Taig would sell soft jaws for their chucks. Should be pretty cheap if they do. I’ll check.
Also if you’re not in any hurry to spend money right now then you can always make up a spacer that fits in the 3 jaw behind the work piece which will do away with the need for your step jaws for now (unless you’re wanting the step jaws to allow for larger diameter rather than chuck face clearance and workpiece support) . I’ll find a pic of a spacer online and will put a link up here to it for you to see. VERY easy to make.
I’ll be baaaack!
BobOctober 21, 2014 at 9:30 pm #59955
Here’s a couple of links to two different types. Anything flat that will fit behind the work piece and cannot fly out of the chuck will pretty much work. You can bore a hole in the one type shown to allow for clearance for your drill and boring bar.October 21, 2014 at 9:47 pm #59956
Forgot to check on the soft jaws. They do have them and they are less than $10 for a set. You can just put those on your chuck and bore or turn what ever diameter you want to hold to whatever depth you would like. You can put a few usable steps in them if you wish. Do mark them so they match in order each time you remove and replace them onto the chuck.
To the soft jaws: http://www.taigtools.com/c1051.html
Hope that helps!
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