bad 4 jaw

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itowbig

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howdy hey.
long time sense ive been in here. illness has me hurt .
any who ive a four jaw (el cheapo) that i got through flea bay (ya i know ) three jaws work great but the fourth now so good at all in fact i threw it into the scrap box. im trying to maybe salvage it but unsure of how .the part that holds the screw into the chuck is bad (the whole design is junk )it binds up so bad that i cant use it at all. thought about making a new screw piece for it but unsure how to keep it in the chuck as the original one is press fit and useless. any ideas as to what to do or maybe trans form this chuck into something else. its for a lil 7x12 i need to order a new 4 jaw from little machine shop when i get some money , but for now id sure like to salvage this junk .

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yes it did fail right away. the keeper failed too , it got hung up on the screw busted off one piece of the thread then chiped the keeper. this chuck has no use on it what so ever. i bought it installed it and tried to use it . thats when that screw failed . this is the second chuck to fail. its just a paper weight right now
 
Sid,

If it is new and has not been forced, then it isn't fit for use, so you should be able to get your money back or a replacement. Maybe you will have to raise an issue through Ebay.

I have a chuck by the same maker (6 jaw self centering) and it seems to be very accurate and well made, but because they are made for a purpose, they should not be overtightened anyway..

John.
 
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blogs this is the second chuck . i sent the other one back . this has been over a year ago . i just gave the seller very bad reviews and just threw the chuck in the junk box im done with the seller. i just ran across it yesterday and thought about weather or not i could fix it or make something else from it. maybe some kinda other fixture or something. im not sure what . i was thinking about making another screw for it , but then i would have to make four of them and then try an deal with the press in holders. its a junk chuck . so it dont matter if i screw it up or not. i like a four jaw better . my 3 jaw is out of wack by a bunch. so i dont like to use it at all. just dont have the funds to get a better 4inch from LMS yet. i cheaped out on buying this chuck . (lessen learned )i should have just went with LMS in the first place. i wasted 100 bucks for a paper weight . 3 inch face plate maybe i dunno. im still pretty new to this so my skills need lots of improvement. im finding this little lather harder to work with than the 9 x 14 i had. (stupid me for selling it ) maybe i can make a heavy finger engine with it hahahahaha :)
 
ok i think im gunna just cut this chuck down and make a flat plate with either a grove or holes for a dog to work in. i was hoping somebody had some other ideas but i quess not. so off to the band saw to cut the baby down to size
 
Seems like a waste to saw it up! Why not fix it? If not that sell it.
 
I vote for cutting it up and using the metal for other things. Playing with chucks to fix them is a waste of time. You need the chuck to work perfecting when you step up to the lathe with a project. Anything less is a hassle.
 
Well...I cut a similar but much longer square scroll for one of these at work - a soil-testing shear box:

http://static.wixstatic.com/media/7754a5_106c401ad9a54454b682fe1b694d2497.jpg_512

It was do-able, though it took a while. I ended up with backlash which didn't matter for me - if you want to do better, I would cut the tool a bit too narrow, and then run up and down nudging it with the top slide until your mark-space is 50-50. Don't forget the clearance on the sides of the tool - it'll have to bend around the scroll, not go straight down like a normal parting tool.
 
"Buy Cheap, Buy Twice" is something my Dad used to say about spanners and it was he who taught me that it's better to save up and buy better.
Unless purchases are well researched "Buy Cheap, Buy Twice" can apply to any tooling, I've had quite a few expected tool failures where something I bough cheap for just one job survived that but then failed later on something else - failures were usually involved in a big socket/big bar/scaffold pole/jump on the end combo ;-)
 
I am of the opinion that metallurgy flaws can occur with any brand. I have seen brand name (Snap On) tools at the scrap yard that were broken in use. These cracked and broken wrenches and sockets were probably returned and replaced under the life time warranty so the real value in buying top brands is the life time warranty.

House brands made in Asia now offer this same warranty because the replacement tool is so inexpensive that the retailer still make money if they need to be replaced. Their business model relies on the home mechanic who uses the tool for light duty and only rarely.

So broken tools can happen with any purchase and it's the warranty that counts. That said I do have tools from generations back that still do the job. They were inherited and I couldn't toss them out so they stay in a portable tool box that I take to job sites. They get the job done even if they look like antiques. These have no warranty remaining.
 
"Buy Cheap, Buy Twice" is something my Dad used to say about spanners and it was he who taught me that it's better to save up and buy better.
Unless purchases are well researched "Buy Cheap, Buy Twice" can apply to any tooling, I've had quite a few expected tool failures where something I bough cheap for just one job survived that but then failed later on something else - failures were usually involved in a big socket/big bar/scaffold pole/jump on the end combo ;-)

yes this is something that i should have followed on because my father also taught me dont buy cheap stuff. but i failed to listen and i have payed the price. i had though about trying to make a better screw for it but . ive just decided its not worth the effort. im trying to decide what to do with it as it is. it was a piss poor desine and in order to repair it would involve many hrs of re-drilling the press fit parts with threaded parts then making new screws all four of them then trying to figger out how to put a square hole in the end of all four screws. its just not worth all the effort. im leaning on cutting it down for something remake it into something else useful besides a paper wieght.
 
I am of the opinion that metallurgy flaws can occur with any brand. I have seen brand name (Snap On) tools at the scrap yard that were broken in use.

Having worked in a Vauxhall dealership workshop I can guess at how most of those wrenches were broken, mechanics regularly use a length of pipe when faced with a problem fastener and they know their guarantee will most likely get them a free replacement ;-)

The point about flaws though, is that although they can occur almost anywhere they are far less likely, to the point where they are extremely rare, when you start with good materials, good designs, good production procedures and good QA & QC, all of which have an associated cost :D
 
yes this is something that i should have followed on because my father also taught me dont buy cheap stuff. but i failed to listen and i have payed the price. i had though about trying to make a better screw for it but . ive just decided its not worth the effort. im trying to decide what to do with it as it is. it was a piss poor desine and in order to repair it would involve many hrs of re-drilling the press fit parts with threaded parts then making new screws all four of them then trying to figger out how to put a square hole in the end of all four screws. its just not worth all the effort. im leaning on cutting it down for something remake it into something else useful besides a paper wieght.

Your father gave you advice with mixed results. If one intends to use an item once it doesn't make a lot of sense to buy the best available. It is just a waste of money. If one is buying for a lifetime of use, buying cheap is a waste of money.

Now, consider that companies change processes and ownership and sometimes that means that the quality suffers but the price stays up. Sometimes a new company will price their top grade tools pretty cheap to gain a bunch of users with the intent on getting a name made so they can sell for a higher price.

Lets take a single item from a well known company. Mitutoyo makes a digital readout caliper. It will read down to the 5 ten thousandth. Harbor Freight also sells a digital readout caliper with the same reading. Comparisons show that they have similar accuracy but the Mitutoyo will cost at least 10 times what the Harbor Freight one will. Is it worth that difference in price? Is it money well spent to go for the Mitutoyo?
 
i did not even think about the t slot part already there. gives me more to think about. Thank You

I'm glad that you liked the suggestion. Really, I've made 'several' although I have a proprietary couple- one on a T&C and another on a dividing head.

Despite a lot of 'blether' about ball races etc, none of mine have them and seem to work-- regardless of not being 'proper'.

Again, there is no need to think that all is lost if you cannot graduate, I've dome a lot of work with nothing more than a strip of white sticky tape as a sort of tape measure around the edge of mine;- until I got better!

All is not lost:rolleyes:

Norm
 
...Lets take a single item from a well known company. Mitutoyo makes a digital readout caliper. It will read down to the 5 ten thousandth. Harbor Freight also sells a digital readout caliper with the same reading. Comparisons show that they have similar accuracy but the Mitutoyo will cost at least 10 times what the Harbor Freight one will. Is it worth that difference in price? Is it money well spent to go for the Mitutoyo?

Well, they both have a similar number of digits on the LCD, but... :)

At work we buy cheap ones. A little while ago a driver of a readymix cement lorry (who, you might imagine, does not need to be skilled or interested in measurements smaller than meters and kilograms - probably 10 kg) was spotted in our (Civ Eng, heavy structures) lab with raised eyebrows and a look of pain, glancing over at a student. 'Isn't that a vernier?', he asked. The student had decided to use it to lever the lid off a tin of paint. Then there was the PhD student burning their way through a piece of wood with the drill in reverse. After having been told once already. Don't get me started :)
 
It is possible to make a new screw and keeper. Years ago I made new screws for a 12" 4 jaw chuck. The sockets can be milled, then finished using a tool in the mill spindle as a slotting cutter. If you don,t want to harden the screws, ETD150 would be a good material to use.
 
It is possible to make a new screw and keeper. Years ago I made new screws for a 12" 4 jaw chuck. The sockets can be milled, then finished using a tool in the mill spindle as a slotting cutter. If you don,t want to harden the screws, ETD150 would be a good material to use.

oh yes but it will require making every one of them. i wont trust this chuck the way it is. . ive ordered and recieved a 4 inch 4 jaw from little machine shop . i just broke down and got a good one. my 3 jaw is 0.27 off and ive screwed it up now by trying to grind it true. so is flippin usless now too.
 

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