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Hello all, I want to introduce myself. My name is Patrick I'm in
Gaithersburg MD. I joined the group to learn something about mini
machining as I'm a novice.
I have a basic knowledge machining/metal work, and good book collection
which helps. My father was in the tool and die trade and a foreman in a
machine shop before CNC machines arrived sometime in the late 60's early
70's. He left the industry when CNC machines started making it big.
He had the chance to learn CNC, I guess he wasn't interested in it. It
was a shame because I think machining was his passion. He passed
on before I could really learn anything about machining from him.
I have made some small metal parts on a small unimat, but I need a
machine thats a little heavier and stiffer than the unimat.
I want to buy a mini lathe and would like to know what the best ala
round models would be. Most of them on the market are Chinese and some
say there decent machines. I would like to make small gears at some
point. Just one of those things I want to do. I've been reading up on
gear terminology and the math involved.
There's something magical about cutting a part out of a chunk
metal............thanks Pat L.

Hi Pat,

You'll get lots of opinions on the small Chinese lathes - especially
around here.

My take is that they're not for everyone. Some call them a kit. In
my books they are, but not in a derogitory sense. If an experienced
machinist just wants a tool to use out of the box then I'd suggest a
more finished product. OTOH, some are happy with a Chinese lathe out
of the box. Maybe they don't need much or happen to score well in
the QA lotto that these things are. But a hobbiest or machinist on a
budget can finish one of the Chinese kits to be quite a cost
effective yet respectable machine. All the castings are there and
most of the machining done. They just need cleaning and checking
over for alignment errors, etc. The improvements to be had by fixing
any issues found are considerable. In the case of a hobbiest the
experience gained along the way is probably well worth while.

Each machine seems to vary. My personal path involved spreading the
feet (much more stable), lapping & adjusting the gibs (huge
improvement) and glueing some plastic (cut from an old CD) behind
the carriage to keep the swarf out of the apron gears. There will be
more refinements but that much got me underway. Starting from
scratch I spent a lot on accessories (DI, DTI, QCTP, scissor
knurler, centre drills, micrometer, callipers, etc.). However, you
may well have inherited a lot of these.

So if one thou tolerances are all that's required and you can live
comfortably inside the capability envelope without non-stop heavy
usage then you'll probably find the experience and trade-offs fine.

John



--- In 7x12minilathe@..., "Patrick" <patlamb41@...>
wrote:

Hello all, I want to introduce myself. My name is Patrick I'm in
Gaithersburg MD. I joined the group to learn something about mini
machining as I'm a novice.
I have a basic knowledge machining/metal work, and good book

collection

which helps. My father was in the tool and die trade and a foreman

in a

machine shop before CNC machines arrived sometime in the late 60's

early

70's. He left the industry when CNC machines started making it big.
He had the chance to learn CNC, I guess he wasn't interested in

it. It

was a shame because I think machining was his passion. He

passed

on before I could really learn anything about machining from him.
I have made some small metal parts on a small unimat, but I need a
machine thats a little heavier and stiffer than the unimat.
I want to buy a mini lathe and would like to know what the best ala
round models would be. Most of them on the market are Chinese and

some

say there decent machines. I would like to make small gears at some
point. Just one of those things I want to do. I've been reading up

on

gear terminology and the math involved.
There's something magical about cutting a part out of a chunk
metal............thanks Pat L.

G'day Kevin & Patrick.
WELCOME!!
The 7x12 is a good little machine for the money inspite of what some
persons imply about "Chinese" goods. Frequently the lathe does need
some improvement to get optimum performance but that is one way to
come to understand your tool. I have difficulties with those who are
critical of the lathe and denigrate things Chinese. It must be
remembered that for most of us, if it wasn't for the cost
effectiveness of the 7x12 we would not have a lathe. I watched eBay
for months and old second hand lathes of know better brands were at
least twice the delivered cost of my lathe and most likely were over
1000km away.
The 7x12 has all the features my Workshop Practice lecturer told us
to look for in a lathe, eg a prism bed, cross slide and compound
slide, back gear (well! pseudo geared headstock), reversible lead
screw, thread cutting ability, thread chasing dial, etc, etc.
The small mass of the lathe is an advantage regarding ease of
installation and mobility. Lastly the variable speed is a real asset.
Instead of labouring over cutting speed selections you just start
slow and crank up the speed until the tool smokes or the lathe
labours.
If buying a 7x12 check to see if the bed has a hardness diagram at
the tailstock end. IMHO this is important to the life of the lathe,
it may even indicate improved accuracy. There seems to be some
variation here with what the vendors are offering. Some 7x12 now seem
to have a better tailstock with a much more substantial foot. Other
features are things like ball oilers on the lead screw and saddle,
way wipers on the saddle.
Some vendors are offering test reports for each lathe showing things
like spindle run out, bed flatness etc.
Remember, it is a fun machine not a production machine; have fun.
Patrick, enjoy the magic!

Gear cutting. It is possible on a lathe by using the headstock and
change gears as an indexer and with a separately driven cutter. I
have read of people using a fixed tool in the cross slide and
traversing the saddle back and forth to cut a gear. You would need
patience. Gear cutting is really the job of a horizontal mill with an
indexing head on the table as a minimum. I have cut gears and the
mill is what I used after I turned up the blanks on a lathe.

One good turn deserves another.
Regards,
Ian


--- In 7x12minilathe@..., "Patrick" <patlamb41@...> wrote:

Hello all, I want to introduce myself. My name is Patrick I'm in
Gaithersburg MD. I joined the group to learn something about mini
machining as I'm a novice.
I have a basic knowledge machining/metal work, and good book

collection

which helps. My father was in the tool and die trade and a foreman

in a

machine shop before CNC machines arrived sometime in the late 60's

early

70's. He left the industry when CNC machines started making it big.
He had the chance to learn CNC, I guess he wasn't interested in it.

It

was a shame because I think machining was his passion. He

passed

on before I could really learn anything about machining from him.
I have made some small metal parts on a small unimat, but I need a
machine thats a little heavier and stiffer than the unimat.
I want to buy a mini lathe and would like to know what the best ala
round models would be. Most of them on the market are Chinese and

some

say there decent machines. I would like to make small gears at some
point. Just one of those things I want to do. I've been reading up

on

gear terminology and the math involved.
There's something magical about cutting a part out of a chunk
metal............thanks Pat L.

Patrick,

Welcome aboard. Although I've not been yet, you might want to check
out Chesapeake Area Metalworking Club (CAMS) www.cams-club.org
Washington, DC and Baltimore, Maryland. Another member in VA I meant
to send this to but I forgot his name. Ed maybe?

Ian,

Hardness diagram? I don't have my lathe yet (8x12) but it should be
in within the next week. What do I need to know about this? I assume
it is only useful in the purchasing decision. Is this right?

Rance


--- In 7x12minilathe@..., "steam4ian" <fosterscons@...>
wrote:

. . .
If buying a 7x12 check to see if the bed has a hardness diagram at
the tailstock end. IMHO this is important to the life of the lathe,
it may even indicate improved accuracy. There seems to be some
variation here with what the vendors are offering.
. . .

One good turn deserves another.
Regards,
Ian

--- In 7x12minilathe@..., "rancerupp" <rupps@...> wrote:

Ian,

Hardness diagram? I don't have my lathe yet (8x12) but it should be
in within the next week. What do I need to know about this? I assume
it is only useful in the purchasing decision. Is this right?

Rance

Hi Rance,

I think Ian's off to bed. It's late in Oz. He mentioned this diagram
the other day. It shows the areas of the bed that are hardened. You're
probably right - good guide when comparing machines. Ian's doesn't
seem to be a straight Sieg. He bought it from Taig in Canberra I
think. Has a few differences. I'm sure Ian will clarify in the AM.

John

Rance, to save you having to wait until Ian is up again and had his breakfast, I think he refers to a little plate riveted to the t/stock end of the bed, showing a cross-section of the bed top with the "important" surfaces highlighted in red, and labeled "Induction hardened and ground lathe bed". At least, that's what my lathe's got.
Andy

born4something <ajs@...> wrote:
--- In 7x12minilathe@..., "rancerupp" <rupps@...> wrote:

Ian,

Hardness diagram? I don't have my lathe yet (8x12) but it should be
in within the next week. What do I need to know about this? I assume
it is only useful in the purchasing decision. Is this right?

Rance

Hi Rance,

I think Ian's off to bed. It's late in Oz. He mentioned this diagram
the other day. It shows the areas of the bed that are hardened. You're
probably right - good guide when comparing machines. Ian's doesn't
seem to be a straight Sieg. He bought it from Taig in Canberra I
think. Has a few differences. I'm sure Ian will clarify in the AM.

John






---------------------------------
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Ian is quite right in what he says - sometimes we all need reminding just what a bargain it is and without it many many people would never get as far as owning a lathe. the same goes for a lot of other Chinese machinery such as the mini-mills and small bandsaws.

Gerry
Leeds UK

From: "steam4ian" <fosterscons@...>
Reply-To: 7x12minilathe@...
To: 7x12minilathe@...
Subject: [7x12minilathe] Re: New member
Date: Tue, 20 Mar 2007 09:57:35 -0000

G'day Kevin & Patrick.
WELCOME!!
The 7x12 is a good little machine for the money inspite of what some
persons imply about "Chinese" goods. Frequently the lathe does need
some improvement to get optimum performance but that is one way to
come to understand your tool. I have difficulties with those who are
critical of the lathe and denigrate things Chinese. It must be
remembered that for most of us, if it wasn't for the cost
effectiveness of the 7x12 we would not have a lathe. I watched eBay
for months and old second hand lathes of know better brands were at
least twice the delivered cost of my lathe and most likely were over
1000km away.
The 7x12 has all the features my Workshop Practice lecturer told us
to look for in a lathe, eg a prism bed, cross slide and compound
slide, back gear (well! pseudo geared headstock), reversible lead
screw, thread cutting ability, thread chasing dial, etc, etc.
The small mass of the lathe is an advantage regarding ease of
installation and mobility. Lastly the variable speed is a real asset.
Instead of labouring over cutting speed selections you just start
slow and crank up the speed until the tool smokes or the lathe
labours.
If buying a 7x12 check to see if the bed has a hardness diagram at
the tailstock end. IMHO this is important to the life of the lathe,
it may even indicate improved accuracy. There seems to be some
variation here with what the vendors are offering. Some 7x12 now seem
to have a better tailstock with a much more substantial foot. Other
features are things like ball oilers on the lead screw and saddle,
way wipers on the saddle.
Some vendors are offering test reports for each lathe showing things
like spindle run out, bed flatness etc.
Remember, it is a fun machine not a production machine; have fun.
Patrick, enjoy the magic!

Gear cutting. It is possible on a lathe by using the headstock and
change gears as an indexer and with a separately driven cutter. I
have read of people using a fixed tool in the cross slide and
traversing the saddle back and forth to cut a gear. You would need
patience. Gear cutting is really the job of a horizontal mill with an
indexing head on the table as a minimum. I have cut gears and the
mill is what I used after I turned up the blanks on a lathe.

One good turn deserves another.
Regards,
Ian


--- In 7x12minilathe@..., "Patrick" <patlamb41@...> wrote:

Hello all, I want to introduce myself. My name is Patrick I'm in
Gaithersburg MD. I joined the group to learn something about mini
machining as I'm a novice.
I have a basic knowledge machining/metal work, and good book

collection

which helps. My father was in the tool and die trade and a foreman

in a

machine shop before CNC machines arrived sometime in the late 60's

early

70's. He left the industry when CNC machines started making it big.
He had the chance to learn CNC, I guess he wasn't interested in it.

It

was a shame because I think machining was his passion. He

passed

on before I could really learn anything about machining from him.
I have made some small metal parts on a small unimat, but I need a
machine thats a little heavier and stiffer than the unimat.
I want to buy a mini lathe and would like to know what the best ala
round models would be. Most of them on the market are Chinese and

some

say there decent machines. I would like to make small gears at some
point. Just one of those things I want to do. I've been reading up

on

gear terminology and the math involved.
There's something magical about cutting a part out of a chunk
metal............thanks Pat L.

_________________________________________________________________
Txt a lot? Get Messenger FREE on your mobile.

Good Morning all.
The bed hardening diagram can be seen on the tailstock end of the
bed; it is simply a foil transfer. Look
up "www.minillathe.org.uk/pictures" to see a photo of the end of a
Chester Conquest lathe which shows the diagram.
Like most things in this world hardening of the ways has both up
sides and down sides. The upside is that it is resistant to wear and
because it has to be ground after the heat treatment it is likely to
be to a closer tolerance. The downside, and hence the need for the
diagram is that the ways are brittle. That means dropping your chuck
on the ways could cause a piece to chip off; see below for my
comments on chuck handling. Don't drop or bang other tools against
the ways either.
Cast Iron is inherently porous and absorbs lubricants, in addition
the carbon particles tend to assist lubrication. The hardening
process binds up the carbon and reduces the porousity making
lubrication more critical.
In summary, the heat treatment of the ways improves resistance to
wear, probably means better accuracy, but requires more care and
lubrication.
Chuck handling: beg, borrow or steal a length of aluminium bar or
tube (note the spelling, aluminim won't work). In Oz, tube is
available quite cheaply from major hardware chains. Its diameter must
allow it to go through the spindle, and the chuck and into the tail
stock taper; the length must be such that it can support a chuck
between the headstock spinndle and the tail stock. When removing the
chuck place a piece of wood on the ways under the chuck. Pass the
tube or bar through the spindle and into the tail stock. You can then
undo the chuck retaining nuts without the risk of it falling onto the
bed. When the chuck is free from the spindle, grasp it securely in
one hand and pull back the bar. Obviously to put a chuck on you
thread the chuck through the bar and locate it on the spindle face.
This method gives you at least one and a half hands to fiddle with
the chuck retaining nuts and washers. This is particularly useful if
during the process you have to grovell round on the floor to the god
of clumsiness to sort out the nuts from accumlated swarf!
At least our chucks can be picked up in one hand. The larger chucks
have a hole for an eye bolt and a change out involves dragging over a
hoist or whistling up a crane. As trainees we each ahd a bar beside
out lathe for the chuck/face plate changes.

I have now finished my coffee and had better reply to yesterday's
business phone messages.

One good turn deserves another.
Regards,
Ian





--- In 7x12minilathe@..., andrew franks <andyf1108@...>
wrote:

Rance, to save you having to wait until Ian is up again and had his

breakfast, I think he refers to a little plate riveted to the t/stock
end of the bed, showing a cross-section of the bed top with
the "important" surfaces highlighted in red, and labeled "Induction
hardened and ground lathe bed". At least, that's what my lathe's got.

Andy

born4something <ajs@...> wrote:
--- In 7x12minilathe@..., "rancerupp"

<rupps@> wrote:

Ian,

Hardness diagram? I don't have my lathe yet (8x12) but it should

be

in within the next week. What do I need to know about this? I

assume

it is only useful in the purchasing decision. Is this right?

Rance

Hi Rance,

I think Ian's off to bed. It's late in Oz. He mentioned this

diagram

the other day. It shows the areas of the bed that are hardened.

You're

probably right - good guide when comparing machines. Ian's doesn't
seem to be a straight Sieg. He bought it from Taig in Canberra I
think. Has a few differences. I'm sure Ian will clarify in the AM.

John






---------------------------------
Now you can scan emails quickly with a reading pane. Get the new

Yahoo! Mail.

Rance, the address is www.mini-lathe.org.uk , and then go to "Lathe pictures".
Now it's my turn to hit the sack.
Andy
steam4ian <fosterscons@...> wrote:
Good Morning all.
The bed hardening diagram can be seen on the tailstock end of the
bed; it is simply a foil transfer. Look
up "www.minillathe.org.uk/pictures" to see a photo of the end of a
Chester Conquest lathe which shows the diagram.
Like most things in this world hardening of the ways has both up
sides and down sides. The upside is that it is resistant to wear and
because it has to be ground after the heat treatment it is likely to
be to a closer tolerance. The downside, and hence the need for the
diagram is that the ways are brittle. That means dropping your chuck
on the ways could cause a piece to chip off; see below for my
comments on chuck handling. Don't drop or bang other tools against
the ways either.
Cast Iron is inherently porous and absorbs lubricants, in addition
the carbon particles tend to assist lubrication. The hardening
process binds up the carbon and reduces the porousity making
lubrication more critical.
In summary, the heat treatment of the ways improves resistance to
wear, probably means better accuracy, but requires more care and
lubrication.
Chuck handling: beg, borrow or steal a length of aluminium bar or
tube (note the spelling, aluminim won't work). In Oz, tube is
available quite cheaply from major hardware chains. Its diameter must
allow it to go through the spindle, and the chuck and into the tail
stock taper; the length must be such that it can support a chuck
between the headstock spinndle and the tail stock. When removing the
chuck place a piece of wood on the ways under the chuck. Pass the
tube or bar through the spindle and into the tail stock. You can then
undo the chuck retaining nuts without the risk of it falling onto the
bed. When the chuck is free from the spindle, grasp it securely in
one hand and pull back the bar. Obviously to put a chuck on you
thread the chuck through the bar and locate it on the spindle face.
This method gives you at least one and a half hands to fiddle with
the chuck retaining nuts and washers. This is particularly useful if
during the process you have to grovell round on the floor to the god
of clumsiness to sort out the nuts from accumlated swarf!
At least our chucks can be picked up in one hand. The larger chucks
have a hole for an eye bolt and a change out involves dragging over a
hoist or whistling up a crane. As trainees we each ahd a bar beside
out lathe for the chuck/face plate changes.

I have now finished my coffee and had better reply to yesterday's
business phone messages.

One good turn deserves another.
Regards,
Ian


--- In 7x12minilathe@..., andrew franks <andyf1108@...>
wrote:

Rance, to save you having to wait until Ian is up again and had his

breakfast, I think he refers to a little plate riveted to the t/stock
end of the bed, showing a cross-section of the bed top with
the "important" surfaces highlighted in red, and labeled "Induction
hardened and ground lathe bed". At least, that's what my lathe's got.

Andy

born4something <ajs@...> wrote:
--- In 7x12minilathe@..., "rancerupp"

<rupps@> wrote:

Ian,

Hardness diagram? I don't have my lathe yet (8x12) but it should

be

in within the next week. What do I need to know about this? I

assume

it is only useful in the purchasing decision. Is this right?

Rance

Hi Rance,

I think Ian's off to bed. It's late in Oz. He mentioned this

diagram

the other day. It shows the areas of the bed that are hardened.

You're

probably right - good guide when comparing machines. Ian's doesn't
seem to be a straight Sieg. He bought it from Taig in Canberra I
think. Has a few differences. I'm sure Ian will clarify in the AM.

John






---------------------------------
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Yahoo! Mail.

---------------------------------
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Thanks for the explanations Ian and others. This makes sense.


--- In 7x12minilathe@..., andrew franks <andyf1108@...>
wrote:

Rance, the address is www.mini-lathe.org.uk , and then go to "Lathe

pictures".

Now it's my turn to hit the sack.
Andy
steam4ian <fosterscons@...> wrote:
Good Morning all.
The bed hardening diagram can be seen on the tailstock end of the
bed; it is simply a foil transfer. Look
up "www.minillathe.org.uk/pictures" to see a photo of the end of a
Chester Conquest lathe which shows the diagram.
Like most things in this world hardening of the ways has both up
sides and down sides. The upside is that it is resistant to wear

and

because it has to be ground after the heat treatment it is likely

to

be to a closer tolerance. The downside, and hence the need for the
diagram is that the ways are brittle. That means dropping your

chuck

on the ways could cause a piece to chip off; see below for my
comments on chuck handling. Don't drop or bang other tools against
the ways either.
Cast Iron is inherently porous and absorbs lubricants, in addition
the carbon particles tend to assist lubrication. The hardening
process binds up the carbon and reduces the porousity making
lubrication more critical.
In summary, the heat treatment of the ways improves resistance to
wear, probably means better accuracy, but requires more care and
lubrication.
Chuck handling: beg, borrow or steal a length of aluminium bar or
tube (note the spelling, aluminim won't work). In Oz, tube is
available quite cheaply from major hardware chains. Its diameter

must

allow it to go through the spindle, and the chuck and into the tail
stock taper; the length must be such that it can support a chuck
between the headstock spinndle and the tail stock. When removing

the

chuck place a piece of wood on the ways under the chuck. Pass the
tube or bar through the spindle and into the tail stock. You can

then

undo the chuck retaining nuts without the risk of it falling onto

the

bed. When the chuck is free from the spindle, grasp it securely in
one hand and pull back the bar. Obviously to put a chuck on you
thread the chuck through the bar and locate it on the spindle face.
This method gives you at least one and a half hands to fiddle with
the chuck retaining nuts and washers. This is particularly useful

if

during the process you have to grovell round on the floor to the

god

of clumsiness to sort out the nuts from accumlated swarf!
At least our chucks can be picked up in one hand. The larger chucks
have a hole for an eye bolt and a change out involves dragging over

a

hoist or whistling up a crane. As trainees we each ahd a bar beside
out lathe for the chuck/face plate changes.

I have now finished my coffee and had better reply to yesterday's
business phone messages.

One good turn deserves another.
Regards,
Ian