a chuck question

UKworkshop.co.uk

Help Support UKworkshop.co.uk:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

condeesteso

Established Member
Joined
10 Mar 2011
Messages
1,929
Reaction score
2
Location
Sevenoaks, Kent
I am a very proud owner of a shiny Startrite Mercury, and it has Jacobs keyed chuck on it. I asked elsewhere here about fitting a keyless chuck, then remembered I have a rather nice Albrecht keyless in a box (came with the Myford).
Here they are side by side
ch1.jpg

I might be in luck here, but need to know how to do this. The Jacobs is marked No33
ch2.jpg

The Albrecht is marked around a collar where spindle goes in (no tech jargon from me): 100 (space) J33
ch3.jpg

Elsewhere the only marks on the Albrecht are the maker name, and 0-10 0-3/8 (I understand that bit :wink: )

So I'm hoping that if I can remove the shaft out of the Albrecht I might be left with a J33 taper inside that chuck. Any advice on the likelyhood of this, and how to properly remove the shaft from chuck (it's well in there).

Here's the Mercury:
ch4.jpg


And final question, the spanner things for those 2 collars (to remove a chuck)... do they have a name, just so I know what I'm looking for :lol: :lol:
ch5.jpg
 

Attachments

  • ch1.jpg
    ch1.jpg
    57.4 KB · Views: 173
  • ch2.jpg
    ch2.jpg
    33.5 KB · Views: 173
  • ch3.jpg
    ch3.jpg
    32.3 KB · Views: 173
  • ch4.jpg
    ch4.jpg
    83.9 KB · Views: 173
  • ch5.jpg
    ch5.jpg
    28.7 KB · Views: 173
condeesteso":pn85alto said:
...[.And final question, the spanner things for those 2 collars (to remove a chuck)... do they have a name, just so I know what I'm looking for :lol: :lol:

C Spanners
 
To separate the taper you will need to clamp the shaft in a good quality three or four jaw chuck on your lathe and use a wedge lever to break the joint, a short sharp tap might shift it easier than brute force levering.
cdfd8ab958.jpg
 
damn - I forgot about the wood lathe chuck sitting right next to us whilst considering the options! the inside corners of the jaws of that chuck should be about right for the diameter involved and the throat behind them is certainly large enough.

then again he has a metal lathe option too........
 
Thanks Chas - I don't have a tapered wedge but got something similar ( a spanner). I have found before that small sharp taps break tapers better than constant force, so I'll give this a go with due caution as the chuck is a nice one I'm sure.
If the Albrecht fits the Mercury I shall be very chuffed indeed.
 
If you can grind an old spanner or similar to a taper fit you will get more effective 'break' shock by tapping it into the gap to spread it rather than levering.
 
A Jacobs no 33 chuck does not necessarily mean is has a j33 taper in the back.
A no 34 chuck has a JT6 in the back for example.
The Jacobs website has the details of what taper is in which chuck which might save you time/effort or disappointment.

FWIW, I like a keyless chuck on a lathe tailstock where is will not rotate but on a drilling machine when they are free to turn, they can be a pita.
You may have a different opinion.


Looks like you might be in luck http://www.jacobschuck.com/MagentoShare ... atalog.pdf
 
Thanks Myford, it looks like I may be lucky, I'll get the shaft out and see. I am used to a keyless on my current bench drill and it's used in woods exclusively, not had problems. I think the Albrecht is a very precise chuck, shame not to make good use of it.
 
Might be a good idea to check that the Albrecht chuck doesn't have a locking screw inside to hold it on the taper. Even without the locking screw some chucks can be a really tight fit on the taper (when you don't want them to be!)
 
Thanks Dick, I nipped over to Jim's today and we had a joint effort, first trying to drill out a hole in end to tap the create a puller... failed badly, the shaft appears to be case-hardened (probably as expected). Then onto big chuck on lathe, wedges etc... nothing. it's very well on. I planned to get on the Albrecht site as there are exploded diagrams there, to see what is actually down inside the chuck, on axis I mean. Hard to see but I read elsewhere do not strike deep inside as it's closed to the taper.
At the moment I'm stuck. If there was a locking screw, would that be inside the jaws deep down in the chuck? This is one of those that I walk away from until I get a good new idea.
 
Back
Top