3 in 1 Update

118 views
Skip to first unread message

Steve Kelly

unread,
Oct 9, 2012, 10:36:38 AM10/9/12
to london-h...@googlegroups.com
Thanks to Ian and Dean for the initial cleaning of the 3 in 1, to Dean amongst other things for the grinder
 and to Ian amongst other things for getting the keys cut.


Update so far:

The machine has not been maintained or used correctly. The apron and saddle ways were packed with grease! and the shanks of indexable lathe cutters have been re-ground to form cutting tools! or should I say a rubbing tools. Hacksaw blades used as shims.


Maintenance is crucial, daily oiling is necessary and oiling and cleaning when in use. if it isn't done you end up where we are now which is dismantling the machine rebuilding and re-lubricating.

There is a fault with the crossways table which results in it getting stuck when traversed too far. This is caused by the tapered crossways Gib which is adjusted by means of a screw head pushing on a slot in the gib which moves it backwards and forwards. The slot has rounded off not allowing the screw to contact and move the gib. I'll re-cut the slot which should prevent this happening but for the time being be careful when traversing the crossways table. There are some parts missing to the crossways screw which may be impacting on this.

The crossways were packed with grease! Someone has gone to a great deal of trouble to do this and there must have been a specific reason , anybody provide any information on this would be helpful. I am not concerned with pointing the finger at anyone, I just want to know if there was an operational difficulty encountered with the machine which the grease was used to sorted out perhaps?

I have had the crossways table off twice (thanks Phil) and gave it a good clean, removed all the grease and re-lubricated with the correct type of oil. I have similarly re lubed the bed ways. There is about 80% less friction in the ways now and movement is as smooth as silk.

I have made a new lock for the tailstock, its fine for the time being but will replace with a longer lasting mild steel one when I get the correct stock.

Cutters:

The idea behind the lathe is to cut the stock rather than rub it to death. I feel I need to emphasise this point given the condition of the cutters I have seen in the hackspace, if your cutter is inappropriate for whatever reason it will rub, at best producing a crumbling chip rather than cutting some nice swarf, ( cast iron is contrary to this).

Using hacksaw blades as shims is a bit hit and miss if you are not prepared to, or cannot grind your cutter down to the correct size (height). The cutting edge has to central to the axis of rotation, it can be ever so slightly high but that is the margin. So if anyone is using indexable carbide tipped cutters with hacksaw blade shims, how are you going to grind your cutter down to the correct height? You can't!


At the side of the lathe there are the shanks of several indexable cutters without the carbide tips that have been ground down as cutters themselves. I doubt very much that the shanks are high speed cobalt 42 steel or tool steel for that matter.

Indexable cutters with carbide tips may not be appropriate for light lathes either, too much chatter due vibration, so do not expect a fine finish with them. Brazed carbide should be fine but presents height problems when sharpening.

So in my opinion, presently we are limited to 12mm shank HSS which will need to be ground to the correct profile etc.

Last thing I did on Monday when I was in was grind down an appropriate HSS knife cutter profile.


I intend doing some cuts to further test the current set up. I'll let you know how I get on.


Cheers

Steve

Russ Garrett

unread,
Oct 9, 2012, 11:02:56 AM10/9/12
to london-h...@googlegroups.com
Massive thanks guys.

FWIW, I have my own set of decent indexable tools which I have used
for the lathe, and I haven't had a problem with chattering with them.

There are plenty of old tool steel blanks (in varying states) in the
wooden drawers by the lathe which would likely be a lot better than
grinding down indexable tools (!).

Russ
--
Russ Garrett
ru...@garrett.co.uk

Ian Henderson

unread,
Oct 9, 2012, 12:08:24 PM10/9/12
to london-h...@googlegroups.com
For information/education, the reason grease is a no no on precision machinery such as the 3 in 1, is that grease attracts swarf and starts acting like grinding paste, rapidly wearing out parts built to very fine tolerances

As Steve has pointed out, the correct lubricant is a very fine machine oil that is regularly wiped and kept clean

Ian

Adrian Godwin

unread,
Oct 9, 2012, 12:52:18 PM10/9/12
to london-h...@googlegroups.com
This is true for the sliding surfaces, which are also the surfaces
most likely to suffer from an accumulation of swarf. Worst of all is
grinding dust and casting sand, which will be caught up even in light
oil. If this happens the surfaces have to be carefully cleaned and
re-oiled.

However, on some machines (e.g. the Myford that I've got a manual for)
a thicker oil, and a specific grease, is recommended for leadscrews
and gears. Swarf should be kept away from these - you don't want swarf
caught in a gear, whether there's grease on it or not. It may be that
someone has previously misunderstood the areas where it should be
applied. The concerns you previously posted about swarf accumulating
in the gearbox should be looked into, as that's not good at all.

Obviously, the manufacturer's recommendation rather than a rule of
thumb should be followed if they advise anything in particular.

Simon Howes

unread,
Oct 9, 2012, 12:55:30 PM10/9/12
to london-h...@googlegroups.com

Thanks guys,

Sounds like you've done a great job.
We did actually oil this machine in the beginning (with the correct oil) and I even took it apart a few times to fix alignment issues. It was working quite well. Sadly it didnt stay that way, and after the fimo incident (chlorine gas attacking the machine) it had to be taken apart in an emergency to treat the trust that had attacked it..

I'd hoped to be able to get in to give it some tlc, but have moved office away from the hax and got quite busy.

Also have my own indexable tooling, sadly indexable tooling left out gets scrapped quickly (as i found to my sadness when I accidentally left my tooling in the toolpost - I came back to a shattered tip and marks in the chuck).

Anyway, glad to hear someone who isnt me is able/willing to do excellent things

Steve Kelly

unread,
Oct 10, 2012, 4:14:38 AM10/10/12
to london-h...@googlegroups.com

@ Russ Thanks much appreciated. Re Indexables, if the finish is to your liking and they are cutting rather than crumbling then fine.Material being cut factors heavily on this as are the inserts, HSS or carbide, and of course the speed.Higher speed, more vibration more potential for chatter in smaller machines.I am quite interested as I may purchace my own set, if they are good to go, saves an awful lot of grinding.What shank size you using?

@Simon What were the alignment issues you were having and any idea why after aligning didn't it stay?

General: Grease has an initial shear force to overcome before it starts lubricating so there will always be resistance to movement.
Yes,There is loads of tool steel which may be ground but if they are not profiled correctly and set at the correct height you will not get a good finish especially in harder stock.So be prepared to follow the profile angles, there is a book in the library on this very subject. I do not want to put anyone off as I positively encourage grinding your own tool set but be prepared, It is difficult! and then, when they lose their edge you have to do it all again.

I should point out that the use of incorrect tooling will impact on the equilibrium of the machine which may have been the problem Simon was having with losing alignment.

Cheers

Steve

Steve Kelly

unread,
Oct 11, 2012, 6:11:28 AM10/11/12
to london-h...@googlegroups.com
Completed a series of test cuts on the lathe yesterday and was impressed with the accuracy and finish.
I ground some HSS cutters and cut various metals, brass, Ali and stainless steel. Finish was really good and as for accuracy,I managed to part off a perfectly parallel 1mm disc and that was without locking the carriage down!,anyone for watchmaking. Lathe is good to go as presently set up but I would justlike to recut the Gib slot and see what difference it makes.
On Tuesday, October 9, 2012 3:36:38 PM UTC+1, Steve Kelly wrote:

Simon Howes

unread,
Oct 11, 2012, 6:37:14 AM10/11/12
to london-h...@googlegroups.com

Wow! Thanks guys. Ace heros :)

SamLR

unread,
Oct 11, 2012, 6:50:57 AM10/11/12
to london-h...@googlegroups.com
so much win! 

Once I have time (HA) I'd love if you could give me a lesson on grinding cutters (and general lathe/mill work). I know a bit but really want to learn more. 

Cheers

S

Tim Storey

unread,
Oct 11, 2012, 6:53:13 AM10/11/12
to london-h...@googlegroups.com
Thank you very much for your efforts and for fixing the mill, it is much appreciated.

+1 to grinding cutters and more advanced lathe work

\t

Simon Howes

unread,
Oct 11, 2012, 7:21:31 AM10/11/12
to london-h...@googlegroups.com

Btw: what did you do with the  tailstock? Someone kept taking it off and letting the gibstrip fall out (and in the process lost the little bits that put pressure on the gib - therefore preventing to tailstock being tightened properly).

I rescued the gibstrip from a pile of scrap metal...
Can  you put a little locktite on the end of travel bolt in the hope it'll dissuade someone from removing it again?

Steff

unread,
Oct 11, 2012, 7:39:18 AM10/11/12
to london-h...@googlegroups.com
On 11 October 2012 11:50, SamLR <sam.lind...@gmail.com> wrote:
> so much win!
>
> Once I have time (HA) I'd love if you could give me a lesson on grinding
> cutters (and general lathe/mill work). I know a bit but really want to learn
> more.

Two Youtube channels that may be of interest:

http://www.youtube.com/user/mrpete222 (Tubalcain, a former machine
shop teacher who has written a lot of manuals for machine shop work)
http://www.youtube.com/user/KEF791 (Keith Fenner, who runs a machine
shop on Cape Cod specialising in marine engineering)

Both have extensive illustration/discussion of machining work, and I'm
pretty sure they both have segments on grinding tools (Tubalcain also
goes into getting the corract tool profiles for thread cutting IIRC).

S

Steve Kelly

unread,
Oct 11, 2012, 9:21:58 AM10/11/12
to london-h...@googlegroups.com

Simon, I must admit I was puzzled by the tailstock locking mech for a while as the drawings in the manual are unclear specifically about this part, so I looked at the locking mech for the carriage which is less ambiguous. I thought it would be a complicated part turns out could not be simpler, it is just a bar of ali which I have mitred on one end to align with dovetail way, this is simply tightened up against the Gib to lock. I'll do one in brass I just need to dimension it.


Gib strip in scrap bin!! Zoot alors


Steph, way to go with the vids. That guy Tubalcain more experience in his little finger.


Sam, no problem once we are up and running


Tim, Thanks much appreciated. I have not got round to the milling machine part of the 3 in1 yet will do shortly though.



Cheers

Steve


On Tuesday, October 9, 2012 3:36:38 PM UTC+1, Steve Kelly wrote:

Simon Howes

unread,
Oct 11, 2012, 9:55:54 AM10/11/12
to london-h...@googlegroups.com

Steve: I was the very final image of a rage comic when I retrieved it from the scrap. Fffuffuffffuffuuffffufuffuufff

Billy

unread,
Oct 11, 2012, 10:22:06 AM10/11/12
to London Hackspace

I've come close to this experience on more than one occasion in the
workshop for similar reasons.

Jose pointed me to these vid's that i've been recommending to people,
http://techtv.mit.edu/collections/ehs-videos/videos

Nice intro's to all the basic kit, and a lot of relevant comments on
safely using them.


On 11 Oct, 14:55, Simon Howes <simonhowes...@googlemail.com> wrote:
> Steve: I was the very final image of a rage comic when I retrieved it from
> the scrap. Fffuffuffffuffuuffffufuffuufff
Reply all
Reply to author
Forward
0 new messages