Box Spanner Fix

[mzt]

Some days ago, I had to apply a pipe to the handle of the box spanner I’m using on the mill, to remove an overtightened drill chuck:
ended with the business end of the spanner breaking into pieces, luckily the chuck was released at the same moment.

This is definitely not a fix, but I needed something made quickly (and it is still working after a few days. Might end up with
press fitting a collar to this one, someday)



 
But I want a more durable one (though the above one reminds me not to overtighten the chuck ANYTIME I’m using it).

Started with this



 
And drilled thru a portion of it to the distance between the flats of the square on the drawbar (8mm),




then some length of it to the distance between the opposite corners (10mm)



 
A quick visit to the marking bench



 
Then to the mill, to drill the four 1.5mm dia holes (some 12mm deep)



 
Took a picture of the other end, too, toghether with the next tool I’ll use, tomorrow.
(I wish I kew where the square file is gone: will do with the triangular one with a little more care).



Passing close to the vise, on my way to bed… ..it’s almost done now, but no pictures yet.

Marcello

[Stilldrillin]

After some careful filing, that will be a great repair Marcello! 

David D

[mzt]

The spanner shaft (a 12mm bolt, should be strong enough for the job) turned to .07mm interference fit,
drilled for the handle, tapped for a set screw.



 
Now in the press, barely within the envelope of the machine
 


Here it is! I’m definitely satisfied with the fit and finish of the square socket.
May add a taper pin, or have somebody welding the parts together, someday.




Marcello

[mzt]

Now I have a working replacement wrench, I can take the risk of fixing the broken one, finally.
First of all, I removed the jubilee clip and paper tape that were holding the loctited part in place,
then put it into the lathe to gain a round end: was not sure about applying intermittent cuts to a glued part,
but it did not move. That material is glass hard, btw. 



 
Next, I turned an alu. collar to press fitting diameter. I suppose steel would have done better, but there
were some alu. tubing odds into the box: too tempting.

Press-fitting the collar. 




The finished job.



 
As for the homemade one, I managed to fit an 1/8" taper pin in it.



I measured the diameter of the pin at (A) and (B), then divided the distance from A to B by the number of drills
I had... then it was only a matter of applying enough force to have the pin squeezed down the stepped hole.


Marcello