locoboy
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| posted on 26/2/08 at 09:38 AM |
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lathe tooling help guidance req!
I am looking for some lathe tooling to do some BASIC turning, i am looking for parting tools and some basic tooling to reduce the diameter of the
stock piece of material.
I have an old stle lathe and having never had to source tooling before im struggling with what kind and size of tooling i need to fit my toolpost.
Can anyone help or point me to some suitable tooling on Ebay etc?
My lathe
 
lathe
ATB
Locoboy
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Mr Whippy
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| posted on 26/2/08 at 09:47 AM |
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I found the carbide incerts very good and they lasted a long time. Just make sure you have plenty of coolant, a fishtank pump does the job
Fame is when your old car is plastered all over the internet
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r1_pete
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| posted on 26/2/08 at 09:48 AM |
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Try these:
Lathe tools
RDG are quite a helpfull outfit too.
Rgds.
Pete.
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locoboy
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| posted on 26/2/08 at 09:50 AM |
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Thanks.
Pete is the parting tool the one 3rd from the right?
I am going to be parting off 50mm round ally bar.
That doesnt look like it will do that..........
what do i need to do 50mm bar?
ATB
Locoboy
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r1_pete
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| posted on 26/2/08 at 10:08 AM |
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Yes thats the parting tool, no it won't do 50mm. Ideally you need a rear parting tool, which fits to the back of the cross slide, I don't
know whey but these do seem to work much better in the smaller lathe than a conventional parting tool.
These look like a tool post with a knife blade, sods law there aren't any on fleabay at the moment.
heres a conventional tool which should do it.
[Edited on 26/2/08 by r1_pete]
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David Jenkins
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| posted on 26/2/08 at 12:10 PM |
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quote:
Originally posted by r1_pete
Yes thats the parting tool, no it won't do 50mm. Ideally you need a rear parting tool, which fits to the back of the cross slide, I don't
know whey but these do seem to work much better in the smaller lathe than a conventional parting tool.
Parting off is a tough process! In the conventional position the work of cutting tries to force the tool downwards and the workpiece, chuck and
spindle upwards. In the rear position the tool is upside-down and thus forced upwards, countered by the fact that rear toolposts are usually big tough
things. Most importantly the workpiece, chuck and spindle are pushed down towards the bed, which offers more resistance.
It's not a huge difference, but on a small lathe you need all the help you can get!
The best parting tool I've got for my small lathe is a skinny blade mounted in a special holder - it's 2 or 3 mm wide. A few examples can
be seen
here.
Parting off in a small lathe is a nightmare. On my big Colchester lathe it's far easier, as I can use auto-feed to push the tool forwards - far
kinder to the tool.
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minitici
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| posted on 26/2/08 at 01:22 PM |
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I find Chronos quite good for lathe tools
Chronos
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locoboy
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| posted on 26/2/08 at 01:29 PM |
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quote:
Originally posted by David Jenkins
Parting off in a small lathe is a nightmare. On my big Colchester lathe it's far easier, as I can use auto-feed to push the tool forwards - far
kinder to the tool.
David,
How do you mean forwards? and what is auto feed?
ATB
Locoboy
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David Jenkins
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| posted on 26/2/08 at 01:59 PM |
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By forwards I meant 'away from me' or 'into the workpiece'.
Auto-feed - instead of winding the handle so that the tool moves into the workpiece, I lift a lever and the lathe itself moves the cross-slide. I
have a gearbox with assorted levers and controls that let me adjust the speed the tool moves.
It has 2 movements - either across the lathe bed (parting off or facing the work) or along the bed (reducing the diameter, or thread-cutting).
All screw-cutting lathes can do the sliding movement along the bed, either via a gearbox or a set of gears that you mount at the end of the headstock.
The cheapest ones don't have this facility.
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locoboy
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| posted on 27/2/08 at 07:46 PM |
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Thanks Dave for the clarification.
Am i looking at causing myself problems if i want to part of 50mm material on this kind of lathe then?
ATB
Locoboy
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David Jenkins
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| posted on 27/2/08 at 09:09 PM |
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Depends on the material! Brass, ali or good mild steel will be fairly easy, as long as you keep to a low speed and use a lubricant (for the steel,
and prob. the ali). If you try to part off one of the tougher steels (silver steel, or half-shafts!) then you probably snap the tool tip off. If you
have the choice, get leaded mild steel - it's a dream to machine (but I wouldn't know where to get it outside of model engineering
suppliers).
I've never liked parting-off, even on the big lathe - it's a tough cut.
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locoboy
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| posted on 27/2/08 at 10:11 PM |
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Its ally i will be doing at the outset. I cant see myself doing anything that big in steel so i guess take it slowly and all should be ok!
What do you recommend as a cutting lubricant for ally?
ATB
Locoboy
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David Jenkins
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| posted on 27/2/08 at 10:23 PM |
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There are all sorts of cutting fluids available - but the cheapest effective one is WD-40 (as recommended by Paul G, a.k.a. "907" ). Just
fit the long tube and squirt at regular intervals into the slot cut by the tool.
Stops your lathe getting rusty too! 
Don't go too slow - about half of the speed you'd use for normal machining, and feed the tool in slowly and steadily - look for a steady
stream of swarf coming off, with no bad sounds of the tool digging in.
[Edited on 27/2/08 by David Jenkins]
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neilj37
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| posted on 28/2/08 at 07:48 AM |
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If the tool starts to chatter when you are parting off be careful as there is a good chance the tool will try to dig in.
Depending on what you are doing it is sometimes easier just cut the piece off with a hacksaw and tidy the face up in the lathe.
The shape of the tool also helps with the parting operation.
This should help you:
http://www.mini-lathe.com/Mini_lathe/Operation/Parting/parting.htm
[Edited on 28/2/08 by neilj37]
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thomas4age
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| posted on 28/2/08 at 09:20 PM |
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I tried parting of twice, and it works but the strain on the lathe and the time it takes is not worth it for me. also make a big mess on the bed
ways.
I'd go with the hacksaw en after that a facing operation, the result is much neater than parting it off.
I'm however in now way an expert, just started to produce my first parts on my new toy, 'but from a beginners point of vieuw I can't
be far off.....
I bought a set of hss Toolbit and they work really wel on anything upto 6085T6 so far, and indeed I've been offered the same advice at cutting
fluid wd40 does the trick, he also told me that if it goes smoking/vaypour the you're cutting to quick, so back off the speed at which you feed
to tool or up the rpm on the lathe.
here's my first purpose made parts, scroll down the page
http://www.locostbuilders.co.uk/viewthread.php?tid=69255&page=3
grtz Thomas
[Edited on 28/2/08 by thomas4age]
If Lucas made guns, Wars wouldn't start either.
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David Jenkins
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| posted on 28/2/08 at 09:32 PM |
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quote:
Originally posted by thomas4age
he also told me that if it goes smoking/vaypour the you're cutting to quick, so back off the speed at which you feed to tool or up the rpm on
the lathe.
Depends on the tool and the lathe! I use carbide-tipped tools on a substantial lathe (still small by engineering shop standards) and if I'm
taking a lot of steel off then the swarf comes away red-hot and turns blue when it cools! I usually wear heavy gloves when I do that, as I invariably
get the swarf on the back of my hand if I'm unlucky... 
A good guide on a smaller lathe is the way the swarf comes off the tool - if it's coming away smoothly and continuously then you're not
far wrong. My record is one continuous length of around 3 metres, and that's with my little lathe (a 1940's Zyto).
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thomas4age
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| posted on 29/2/08 at 12:30 PM |
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still limited myself to toolbit bits and T6 alloy David,
I understand that if you want to do steel you'd beter by tungsten tipped bits instead of HSS toolbit items. or something with the yellow plates
(Widia) on it....
any picture of you lathe perhaps?
grtz Thomas
If Lucas made guns, Wars wouldn't start either.
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David Jenkins
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| posted on 29/2/08 at 12:38 PM |
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This is what the the big 'un looks like:
Weighs more than my Locost, and cost me £200 (+£100 for transportation home).
This is what the little 'un looks like:
That cost me something like £50 - £75.
Both were built in the early 1950s, and both are a bit worn out - they do all I require though.
[Edited on 29/2/08 by David Jenkins]
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David Jenkins
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| posted on 29/2/08 at 12:43 PM |
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quote:
Originally posted by thomas4age
I understand that if you want to do steel you'd beter by tungsten tipped bits instead of HSS toolbit items. or something with the yellow plates
(Widia) on it....
The tungsten tools that you can buy in places like Chronos are easier to set up, but they are often not the best shape for a small lathe - they work
best when cutting by brute force in a strong lathe. HSS is best for small lathes, as long as you grind the shape correctly - which is an art in its
own right!
I read in an old model engineering book that the best way to learn how to grind tools was to use them on a treadle lathe - you soon know if the tool
is cutting inefficiently, as your legs complain!
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