MadModder

The Shop => Tools => Topic started by: jim on December 24, 2011, 11:18:57 AM

Title: word of warning!!!
Post by: jim on December 24, 2011, 11:18:57 AM
been getting loads of roundtuit jobs done the last few weeks :bugeye:

last job on my list was fixing the emergency stop on the small lathe (sieg C3)  :dremel:

job done and tested ok :thumbup:

i noticed that it stopped the spindle almost instantly, for some reason i kept upping the revs and hitting the E stop, marvelling at its stopping ability!!

the end result was a snapped belt  :Doh: :Doh: :Doh: :Doh:

ARC will be getting another one of them "may as well have that as well" orders (that be the third one in 6 weeks) when the Christmas break is over!!

Title: Re: word of warning!!!
Post by: ketanswali on December 24, 2011, 12:15:58 PM
  :Doh:
I would suggest you check their website for availability. If ARC has it, you might as well order it. Their web ordering system is working, even though the telephone lines are closed until 5th January 2012. They might even ship it out on Wednesday next week by first class post.

Merry Christmas Jim and all.

Ketan at ARC.

Title: Re: word of warning!!!
Post by: jim on December 24, 2011, 01:06:55 PM
  :Doh:
I would suggest you check their website for availability. If ARC has it, you might as well order it. Their web ordering system is working, even though the telephone lines are closed until 5th January 2012. They might even ship it out on Wednesday next week by first class post.

Merry Christmas Jim and all.

Ketan at ARC.

 :thumbup:
Title: Re: word of warning!!!
Post by: John Swift on December 24, 2011, 02:06:35 PM
Hi Jim ,

I guess you have one of the later versions of the lathe ,
that has a relay connect a 27 ohm breaking resistor across the motor  when the mains is disconnected.
( something I've only seen on Real Bull lathes not Sieg )

the old Machinemart CL300M (Sieg  C2 )  lathe I have just coasts to a stop

while its a pain the belt failed , It would of been a bigger job if the plastic double gear on the spindle broke
( can happen if the parting tool digs in and jams the spindle)

despite Ketan's advice , I have fitted the 3 part metal replacement from ARC
its made more difficult because the original keyway in the spindle is too short
the original key only can drive one gear and the spacer

at the same time , I fitted taper roller bearings to the spindle and brass gibbs to the top slides

make it a lot easier to part off   (no longer something to avoid)

  John
Title: Re: word of warning!!!
Post by: jim on December 24, 2011, 02:34:22 PM
i think the bigger chuck may not have helped!!

i'd guess its a probably 4 years old (i bought it second hand).
Title: Re: word of warning!!!
Post by: ketanswali on December 24, 2011, 02:59:01 PM
If you have a bigger chuck on your lathe, I presume you already have already installed taper roller bearings 30206s on?.....
ARC will probably introduce angular contact ball bearings for the headstock in 2012. You could use these instead of the taper roller bearings. The bearings will be 7206B-2RS. Dimensions will be same as existing 6206-2RSs....where as the taper roller bearings 30206 are wider.  Another advantage of these angular contact bearings will be that they will be with rubber seals...unlike the tapper roller bearings, and they will be more freer running than the taper roller bearings. They have a lower load carrying capacity than tappers, but this is not an issue for this application. Just like taper roller bearings, you will be able to adjust the pre-load on these bearings.
Title: Re: word of warning!!!
Post by: jim on December 24, 2011, 03:05:29 PM
i changed the bearings a few months ago :thumbup:

Title: Re: word of warning!!!
Post by: jim on December 29, 2011, 10:50:07 AM
got my new belt this morning :thumbup:

excellent!!!
Title: Re: word of warning!!!
Post by: John Swift on December 29, 2011, 11:26:36 AM

Hi Jim ,

great , now your lathe is working again

what are you going to do now , only hit the emergency stop when you have to
 
or have a look at changing the breaking resistor ?    ,   I'm assuming your not refitting the original chuck

  John
Title: Re: word of warning!!!
Post by: jim on December 29, 2011, 11:51:28 AM
i'll be leaving the estop well alone now, lesson learnt!!!!!!!!!!