Chuck repair help needed

[mathsmanParticipant @mathsman]

After speaking to the chuck man at Pratt Burnerd ( David Stanley ) about my ancient 6" independent 4 jaw, I was directed to "Rotagrip" for replacement operating screws.

The price of a couple of new adjuster screws from Rotagrip would buy me a new Chinese chuck !!!!

What is going on?? Does Rotagrip by any chance have new mandarin speaking owners trying to increase their trading share??

Or is it just good old ripoff Britain pricing itself out of the market???

Can anyone suggest a source of operating screws at a sensible price ?

Thanks

[mathsmanParticipant @mathsman]

[davebParticipant @daveb17630]

It's only a screw. Isn't this the sort of thing you make on a lathe?

I modified some 1/2" BSW Allen grub screws to replace the screws on my Pratt 4" chuck, has anyone made new screws to suit the 6" chuck?

Dave.

[RobboParticipant @robbo]

New screws can be made from 1/2" grubscrews as Dave suggests, there was even an article about it in a MEW, whose issue number I forget. I think the screws are the same on both 4" and 6" chucks, but will check.

Of course the grubscrews will have a hex hole in the end, not a square one, so either make a set of four or have two keys.

I can look up the MEW issue if you want, and copy you the article. May even have a few grubscrews left

Phil

[colin hawesParticipant @colinhawes85982]

These screws usually break across the square hole when the chuck key is used to unscrew the chuck. I have repaired two or three by welding. Hint :a square aluminium plug can help stop weld metal obstructing the hole. Colin

[jonathan heppelParticipant @jonathanheppel43280]

Don't blame Rotagrip. Their prices just represent the true cost of pro grade industrial kit, though I wouldn't be hugely surprised if the Pratt screws come from the same factory as the cheap ones.

As for using a chuck key to remove a chuck, well…………..

[RobboParticipant @robbo]

Got it wrong there I'm afraid – have to go to Specsavers again. The screws on the 6" chuck are much bigger, probably a nominal 3/4", but the thread is 8tpi, so does'nt match up with a BSW form, which would be 10 tpi for this dia..

The only problem with making them from bar is making the square hole in the end.

Phil

[mathsmanParticipant @mathsman]

Thanks for the input guys, biggest problem is that my lathe is non screw cutting and hence very limiting.

I'll try the grub screw idea if I can obtain, say, hex socket heads with same/similar thread ( pigs might!! ).

Unfortunately the northeast is not over endowed with engineering suppliers so Google is in for some overtime.

Thanks to all.

[Alan GirvanParticipant @alangirvan88520]

I think my chuck is the same as the one you have, same name, same size. One or two were broken on my chuck I could not source new ones so i decided i would have a go and make some. I made 5 and found they worked well so I have one left and three old ones left which seem servicible. you can have them for cost of postage. The size of screws just under 2.5 inches long 8 theads tpi. The thread is left hand and the chuck key is 8hex.

If you would like to try them and then decide you would like me to make you some I can do so for a small cost.

Regards, Alan.

[mathsmanParticipant @mathsman]

Alan, that sounds a good deal to me, thanks.

I've replied via "Message member" but the forum reply system doesn't confirm whether or not my message got to you, hence this "public" posting. Hopefully we can establish contact.

mathsman

[JasonBModerator @jasonb]

Mathsman if you look in your to your inbox (Top green bar on page), then select sent box it will either say "unread" against the message or the date and time it was read.

 

J

Edited By JasonB on 06/10/2013 20:51:26

[Alan GirvanParticipant @alangirvan88520]

Hi, I have sent you a message to see if you get it as i didn't receive anything from yourself. I can see it is currently sitting as 'Unread'.

Hopefully you will get it and then we can exchange details.

Alan

[Nigel McBurney 1Participant @nigelmcburney1]

I have found Rotagrip very good to deal with,and very knowlegeable,dont blame them for Pratt burnard prices,Pratts spares have always been very highly priced,

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