DSEL74 27th November 2014, 11:17 AM I used my fixed steady today for the first time and I am unsure if this is normal. I have read the roller bearing otype do leave more marking than the brass tipped kind. However I think this excessive.
http://tapatalk.imageshack.com/v2/14/11/26/6cfca5f9a913f2f3e44718e4765e1643.jpg
http://tapatalk.imageshack.com/v2/14/11/26/95f9ac0ae9396bf029b51e5e2cb561cd.jpg
http://tapatalk.imageshack.com/v2/14/11/26/64359b2a39767aa4c8beb196004a346f.jpg
It is very think like guiding or flakes of fine tin foil. Very shiney almost chrome looking.
What did I need to do differently or correct??
cba_melbourne 27th November 2014, 11:48 AM It could be one or more of the following:
- you have applied excessive pressure on the fingers?
- the workpiece was excessivley heated by cutting, and has expanded onto already tight fingers?
- the ball bearings may be worn and prone to seizing?
- you have allowed chips to fall onto the track of the ball bearings? That is the greatest problem of having bearing tipped fingers on a steady. Chips and metal dust tends to be rolled between bearing outer race and workpiece and can build up onto the workpiece therby increasing finger pressure and causing scoring.
- are you using too high an rpm? Consider that the rpm of the bearing depends on the relation between workpiece circumference and bearing circumference - looking at your pic this relation is easily 10:1. This means if you were to spin the workpiece with 2000rpm, the finger bearings would spin with 20,000rpm. And that may be too much, especially if you did not lube them for a long time.
RayG 27th November 2014, 11:50 AM Hi Dale, It wasn't off center or too tight by any chance?
Ray
Stustoys 27th November 2014, 12:00 PM I'd say there is something wrong with the way you set up the steady. Did you just clamp the bar in the chuck, wind the fingers in and go at it?
You need both ends of the bar pretty much on the spindle axis.(the shorter and larger the bar the closer you need to be)
There are likely a dozen different ways to go about it.
If the bar is running true at the chuck you can set the steady up there and then slide the steady along to where you want it. You'll want to loosen the chuck to let the bar move if it needs to. *
You can use a DTI on the far end of the bar with the chuck just nipped and bump the end to get it running true(without the steady fingers touching it of course).
If its a heavy/long work piece you can sit it in the steady and scribe a circle on the end of the bar and move the steady to line the center of the circle up to a center in the tailstock.*(havent used that one)
Stuart
*these methods assume that certain other parts of the lathe are inline.
DSEL74 27th November 2014, 12:15 PM Ray I centred it up against the chuck then moved it down to the end.
The item is the pillar from a drill and was being lightly sanded, so not hot from cutting etc.
No chips to start with.
It hasn't been used in years and as the Colchester is the only thing left at my parents after the moved I forgot to bring any oil. so that may be a possibility
I wound the fingers in until I felt them press firmly the knurled section is very large so I may have applied to much force unknowingly. How much is enough but not too much???
DSEL74 27th November 2014, 12:17 PM Come to think of it I was using the 3 jaw chuck and it is running out so that would put the steady out in relation to it.
DSEL74 27th November 2014, 12:20 PM Also for reference the lathe is a Colchester Master 2500 (4ft Bed)
pipeclay 28th November 2014, 12:15 PM Going by your method of set up , can I take it that you didnt indicate the job in your 3 jaw.
If by some chance you did did you then indicate the outer end of the job.
If by some chance you did indicate the outer end of your job did you re indicate it after fitting the steady.
If you by some chance did indicate the outer end of the job when fitting the steady did you adjust the fingers to get the outer end of the job running true.
If by some chance you did not indicate the job in the 3 jaw or the outer end of the job before fitting the steady or even after fitting the steady I would say that the majority of your damage has been caused by the job not running true and trying to walk its way out of the chuck and steady.
Was there a centre fitted to the outer end of the job,if so you may of been fortunate that the job didnt come out of the chuck.
Your method of fitting the steady is to a point somewhat normal practice but relying on the inner end ( chuck ) running true to the outer end should not be considered, both ends need to be running true for this method and then still an indicator used when adjusting the fingers to confirm that nothing has moved.
DSEL74 28th November 2014, 01:51 PM Pipeclay no indicator was used.
A longwinded answer but I see a proper set up is required for even simple polishing job. Thanks for the best practice methodology
morrisman 28th November 2014, 08:49 PM What grade of steel is that ? The swarth looks weird ? The tool appears to be tearing the work .
Mike
DSEL74 28th November 2014, 08:52 PM It is the pillar from a 1940 waldown. No idea of the actual steel.
pipeclay 28th November 2014, 08:58 PM What grade of steel is that ? The swarth looks weird ? The tool appears to be tearing the work .
Mike
There was no TOOL,it was caused by the job running in the steady.
morrisman 28th November 2014, 10:36 PM There was no TOOL,it was caused by the job running in the steady.
Hmmmm very strange :o:C
Steamwhisperer 28th November 2014, 10:43 PM I have no doubt you have checked this already Dale but I have to ask.
None of the bearings on the steady had stopped turning during the job even though they might all be turning now.
Sometimes a bit of crud can jam them and stop them turning.
Just a thought.
Phil
BaronJ 28th November 2014, 11:29 PM Hi Guys,
Strange ! It looks to me as though the lip on the work next to the steady has been running against the faces of the bearings. You can see rub marks on the steady fingers. It might also explain the torn up edges.
Just my 2 cents worth. :)
snapatap 30th November 2014, 08:28 PM We have a Colchester magnum at work, the steady is the same design as yours just bigger. No matter how much care and attention i put into setting the steady it always leaves a mark and makes little flakes like in your picture. I think there is a design or manufacturing flaw with their steadies. The marking you have on your bar is pretty bad and I would agree with the others that it is partly caused by the bar running out/ steady not set properly. On another not if any of you ever see a Colchester Magnum for sale don't buy one, they are the worst lathe i have ever operated.
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