savage 18th October 2006, 12:27 AM G'Day all,
Just bought a chunk of 50mm round bar and wish to turn it down, problem is the jaws of the chuck fall out at 50mm so I can not hold it safely to even turn the end down for a more secure grip. Is my only choice to buy a larger chuck?.. Or is there a way to hold it with the chuck I have?...I have thought about finding the centre, use a 12mm drill and go in about 5mm, then weld a short smaller dia bar that I can get a safe grip on it in the chuck, do you think this would work?....:confused:
Oldhack 18th October 2006, 07:14 AM what you suggest may work if you can get a good weld on it, the trick will be welding it on centre.
you dont say what type of chuch your using, if its a four jaw you should be able to reverse the jaws.
the other alternative is to turn it between centres
JMT
peternl 18th October 2006, 01:39 PM If you have a faceplate and a dead center for your spindle and tailstock, you could turn it between centers. Install the faceplate and dead centers, center drill the two ends of the bar stock, mount it between centers. You need a lathe dog of some kind to then turn the stock - you could jerry rig something easily enough, perhaps drill and tap a hole in through the end.
Another method would be to drill and tap a whole in the end, insert a bolt and tighten it up (perhaps usie locktite as well), center drill the other end, and then hold the bolt head in the chuck and the other end in the tailstock live/dead center.
cub3 18th October 2006, 05:15 PM Savage,
Small chuck if it cannot hold 50mm. ;) My 4 jaw is 630 mm dia & will swing 710mm in gap.
Can you buy a set of external jaws for your chuck? also called reverse jaws.
Regards
Den.
savage 18th October 2006, 05:47 PM what you suggest may work if you can get a good weld on it, the trick will be welding it on centre.
you dont say what type of chuch your using, if its a four jaw you should be able to reverse the jaws.
the other alternative is to turn it between centres
JMT
Savage,
Small chuck if it cannot hold 50mm. ;) My 4 jaw is 630 mm dia & will swing 710mm in gap.
Can you buy a set of external jaws for your chuck?
Regards
Den.
If you have a faceplate and a dead center for your spindle and tailstock, you could turn it between centers. Install the faceplate and dead centers, center drill the two ends of the bar stock, mount it between centers. You need a lathe dog of some kind to then turn the stock - you could jerry rig something easily enough, perhaps drill and tap a hole in through the end.
Another method would be to drill and tap a whole in the end, insert a bolt and tighten it up (perhaps usie locktite as well), center drill the other end, and then hold the bolt head in the chuck and the other end in the tailstock live/dead center.
Thanks Guy's I knew someone out there would have an idea.
Peter as I am just starting to turn metal, my gear is a bit on the lean side so your second option will be Plan "B", Thanks for the reply.:)
Den, I was thinking about a 4 jaw chuck, as I will need one sooner or later, I guess it could be sooner. If all else fails that will be Plan "C", Thanks for the reply.:)
JMT, I only have a smallish 3 jaw chuck, but you may have hit the nail on the head, as each jaw is stepped, but I think the steps are on the outside not the inside, (if you know what I mean), I don't think I can reverse the jaws in the chuck. Thanks for the reply.:)
cub3 18th October 2006, 05:57 PM Eric,
Sorry it's plan C :confused: you should be able to to buy said jaws for a 3 jaw chuck, very useful.
zathras 18th October 2006, 09:25 PM Grind some flats so it will fit in the chuck?
graemet 18th October 2006, 10:28 PM Eric,
If your lathe is new, your chuck should have a set of "outside grip" jaws in the accessory box if the present jaws have curved teeth to engage the scroll, but if the jaws have straight teeth, they can be reversed. My lathe came with a 3 jaw and a 4 jaw chuck but the 4 jaw was so sloppy, it was useless. I bought a much better one from H&F - their cheapest! and bolted it to the backing plate of the original one after removing the jaws.
I couldn't do without the 4 jaw independent now.
Cheers
Graeme
beglobal 19th October 2006, 06:56 AM what you suggest may work if you can get a good weld on it, the trick will be welding it on centre.
you dont say what type of chuch your using, if its a four jaw you should be able to reverse the jaws.
the other alternative is to turn it between centres
JMT
I agree with u!!!!
savage 19th October 2006, 04:52 PM Eric,
Sorry it's plan C :confused: you should be able to to buy said jaws for a 3 jaw chuck, very useful.
Grind some flats so it will fit in the chuck?
Eric,
If your lathe is new, your chuck should have a set of "outside grip" jaws in the accessory box if the present jaws have curved teeth to engage the scroll, but if the jaws have straight teeth, they can be reversed. My lathe came with a 3 jaw and a 4 jaw chuck but the 4 jaw was so sloppy, it was useless. I bought a much better one from H&F - their cheapest! and bolted it to the backing plate of the original one after removing the jaws.
I couldn't do without the 4 jaw independent now.
Cheers
Graeme
I agree with u!!!!
Cub, Greame, Thanks you where right on the money, Cub, you where right in the respect that the jaws are changable with another set (reversible). Greame, you where right as I went out and looked through the box of bits that came with it and sure enough there they where wrapped up in a tight little bundle under all the spare gears, and I found another morse taper I was unaware of. So now I have a large and small taper and a set of reversible jaws, when it was delivered I didn't even get an instruction booklet so I was unaware of what came with it. The guy just said it was a box of spares, the tools came in a bag separate and he said it was ready to go!....:)
Zathras, thanks for your input as that was a consideration I was toying with.:)
Beglobal, What can I say but glad you agree!...:rolleyes: Seriously, thanks for taking the time to read my thread.:)
savage 19th October 2006, 07:08 PM Yay!....It's in, and I'm going to start turning tomorrow, Thank's again for all your help!....:) :) :) :) :)
Andy Mac 19th October 2006, 10:33 PM Good to hear it was an easy fix, and you got the right info with no dramas from the forum members! Its a great place to swap info and experience!!:D
I've had the same problem, v. embarassing to keep winding the jaws out, and to avoid repeating, maybe write the max. diameter on each set of jaws in oil pen:rolleyes:.
Cheers,
savage 20th October 2006, 12:17 AM Good to hear it was an easy fix, and you got the right info with no dramas from the forum members! Its a great place to swap info and experience!!:D
I've had the same problem, v. embarassing to keep winding the jaws out, and to avoid repeating, maybe write the max. diameter on each set of jaws in oil pen:rolleyes:.
Cheers,
Yes, I must agree Andy, just about 99.99% members here are good people and the 0.01% don't matter anyway.
I did find out that when changing the jaws, they each have there own slot they fit into or they do not centre equally. So I am going to engrave each jaw to it's home slot.
Last time I did any turning wood or metal was a long time ago in school, but I know I am not alone there, as some members have stated that fact numerous times before me.:o
Grahame Collins 20th October 2006, 09:34 PM For those without a 4 jaw chuck, I was able to do this on a big 3 phase.
The 3 jaw is far too heavy to remove with mechanical assistance,which I did not have.
Hex bar fits real well in a 3 jaw chuck. I found center on 1 end by using a centrefinder and pop marked it.. Marking a circle with dividers, the od of the hex bar, I was able set it up on centre. I tacked every other flat with the welder. Good tacks- higher than normal amps ,ok!
Used a live centre on the other end. Not fitter and turner like but if you can't weld, heat,or hammer it takes the fun out of turning.
Spun it up real careful like, as them big chunky bits can get nasty if they come loose.
There is always a way, if you take care.
Grahame
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