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Well, what is adequate to you depends on what you want to do. In my
opinion, lathe/mill combinations tend to be a compromise all around and,
like most compromises, don't do anything all that well. But there is also a
range of these products available and one of them might be fine for you.

If you are only doing a little light hobby work, or space is extremely
critical, it could be OK. The really little ones (like what Micro-Mark
sells) could be OK for that, but for anything any semi-serious I think it is
something one could regret.

However, I have yet to hear anyone say they regretted having a separate
lathe and mill and wanted to trade for a combo.

Another option is getting a suitable lathe and, if your milling needs aren't
too great, get a milling attachment. You could then defer getting a mill
right off the bat.

Chuck K.

Steel is more than twice as rigid as aluminium while CI is only about
half again as rigid as AL. A relatively thick steel adaptor (say about as
thick as the spindle flange might give you the best results. A really
close fit on the spigot is good too.

Bill in Boulder "Engineering as an Art Form!"

I have never seen anything on this idea but would be very interested to
find out what you learn. I am going to review the instructions on my
bicycle speedometer to see what I can figure out on my own!

Bill in Boulder "Engineering as an Art Form!"

Roy Lowenthal wrote:
I'd be leery of modifying to a roller bearing; the thrust loads
aren't large enough to require it. Personal opinion is that a
shielded ball bearing is more likely to give long life than an
externally shielded roller bearing.
With missing pieces & a headstock full of swarf, contacting HF and
making it their problem sounds like a superb idea. They've got a
pretty good customer service reputation.
On mine, I had to braze shut & redrill the index holes on the
speed change (gear shift) lever. The factory holes gave pitiful gear
contact on one speed & rubbed against the housing on the other.

Roy

--- In 7x12minilathe@..., Geoff Steckel <gwes@o...> wrote:

Geoff Steckel wrote:

I bought the Harbor Freight lathe and the advertised quick change
toolpost some months ago. The only way I've been able to use any
tool bigger than 1/4 inch is with the quick change unit, and only
then by lowering the tool holder well below the level of the cross
slide. It works, but it's not pretty.

After spending about 10 hours tightening every gib in sight,
polishing the ways, and other miscellaneous fixups, I am now
trying to replace the spindle bearings in hopes of getting
less play and flexing. The Harbor Freight model had straight
roller bearings, so I'm replacing them with angled bearings
to take thrust loads.

It's not clear that there are missing pieces. The parts list
and diagram in the manual show only one nut on the end.
Sounds like there was a design change somewhere.

It's been almost a year since I bought the lathe. Will HF
go so far as to replace a unit which is now mostly a pile of
parts on my bench? It would be very nice if they would but
I feel a little nervous making that phone call.

Geoff

4203 is the number of the latest issue.

Robert, I just posted a new page "Getting Started with
your Minilathe" which you may find helpful.

Go to mini-lathe.com and click on "Getting Started"

Frank Hoose


--- robt2112 <robt2112@...> wrote:

I am planning on buying a Speedway lathe. This will
be my first one.
I was wondering if someone could give me some
pointers on items that
I will need to purchase with my lathe to start me
off?
Thank You
Robert



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The 7x10 group is at:


I'd be leery of modifying to a roller bearing; the thrust loads
aren't large enough to require it. Personal opinion is that a
shielded ball bearing is more likely to give long life than an
externally shielded roller bearing.
With missing pieces & a headstock full of swarf, contacting HF and
making it their problem sounds like a superb idea. They've got a
pretty good customer service reputation.
On mine, I had to braze shut & redrill the index holes on the
speed change (gear shift) lever. The factory holes gave pitiful gear
contact on one speed & rubbed against the housing on the other.

Roy
--- In 7x12minilathe@..., Geoff Steckel <gwes@o...> wrote:

Geoff Steckel wrote:

I bought the Harbor Freight lathe and the advertised quick change
toolpost some months ago. The only way I've been able to use any
tool bigger than 1/4 inch is with the quick change unit, and only
then by lowering the tool holder well below the level of the cross
slide. It works, but it's not pretty.

After spending about 10 hours tightening every gib in sight,
polishing the ways, and other miscellaneous fixups, I am now
trying to replace the spindle bearings in hopes of getting
less play and flexing. The Harbor Freight model had straight
roller bearings, so I'm replacing them with angled bearings
to take thrust loads.

The stock bearings had about .8 mil static runout.
The dynamic runout was bad (> 5 mil, AFAIK) at speed.
We'll see if this improves it.

Michael Wood, Cincinnati" <michaelwood@f...> wrote:

Can you give us the play by play on this modification? I'd like to

know

how it turns out. Mike Wood

Will do - right now I'm trying to figure out how to load
the bearings properly. See below ->


"roylowenthal" <roylowenthal@y...> wrote on
Sat, 30 Aug 2003 04:32:03 -0000:

The "standard" fix is to machine most of the "step" off the top

of

the compound & some off the bottom. JWE has posted details, IIRC,

in

the 7x10 files.

The 7x10 files? I must have missed them - I know about the

minilathe

web site.
I was wondering whether that mod would weaken things too much.
Good to know that somebody has tried it successfully.

Are you sure about the bearings?

No, but it's the only thing left to try.

Bearing preload/end play is adjustable with the 2 nuts on
the geared end of the HS. Loosen the outer nut, adjust play with

the

inner nut, tighten the outer (lock) nut against the inner nut.
Repeat as necessary to allow for the outer nut moving the inner

nut

against its threads!

My lathe only has one nut, which was fully tight. The bearings are
simply pressed in and held with plates screwed onto the headstock.
This is why I'm being so drastic.

The HF I've got uses 6206ZZ bearings;
62 mm OD, 30 mm ID, deep groove ball bearing, double shields.

On reading about the deep groove bearings they really don't seem
to be able to take large axial loads. Better than the shallow ones
but not good.

I've spec'ed 30206M tapered-roller bearings from McMaster-Carr.
They turned out to be Timken. They're about 1mm wider than the
originals.
I will have to mill out the bearing seats slightly to clear the
outer roller ring.

One unpleasant surprise on removing the headstock was a large
pile of shavings from the unlubricated fiber-epoxy drive gears.
Not sure what to do here.

I got Belleville washers to apply pressure to load the bearings.
Also I intend to put felt discs in to hold oil and protect the
bearings from dirt. By adjusting the torque on one cover plate
I hope to load the bearings properly. I may have to machine a
new spacer to make the distances come out right.

Doing ASCII art for this was too much. See

for an attempt at a drawing.

The total cost is quite low (less than $35). Getting the last
bits correct is going to be a treat.

Geoff

--- In 7x12minilathe@..., Geoff Steckel <gwes@o...> wrote:

"roylowenthal" <roylowenthal@y...> wrote on
Sat, 30 Aug 2003 04:32:03 -0000:

The "standard" fix is to machine most of the "step" off the top
of the compound & some off the bottom. JWE has posted details,
IIRC, in the 7x10 files.

The 7x10 files? I must have missed them - I know about the
minilathe web site.
I was wondering whether that mod would weaken things too much.
Good to know that somebody has tried it successfully.

Lots of us have. It works great. I think most who do it are so
happy they stay in the shop and never report their success. :-)

Bearing preload/end play is adjustable with the 2 nuts on
the geared end of the HS. Loosen the outer nut, adjust play with
the inner nut, tighten the outer (lock) nut against the inner nut.
Repeat as necessary to allow for the outer nut moving the inner nut
against its threads!

My lathe only has one nut, which was fully tight. The bearings are
simply pressed in and held with plates screwed onto the headstock.
This is why I'm being so drastic.

This may be a good reason to return it to HF and get a new unit -
parts are missing.

One unpleasant surprise on removing the headstock was a large
pile of shavings from the unlubricated fiber-epoxy drive gears.
Not sure what to do here.

Another reason. And if you haven't used this lathe much, it could
be a "returned unit" and may have been used/abused before you got it.

Or, since you have the headstock apart anyway, install new gears.
Little Machine Shop can get them to you fast.

I got Belleville washers to apply pressure to load the bearings.
... By adjusting the torque on one cover plate
I hope to load the bearings properly. I may have to machine a
new spacer to make the distances come out right.

If you insist on changing a decent design, install the tapered
roller bearings with the tapers opposing, so that tightening the
spindle nuts (get or make another) will tighten the bearings. That
way if things are too tight and start to heat up, the expansion will
make them looser and -maybe- prevent their destruction.

Also I intend to put felt discs in to hold oil and protect the
bearings from dirt.

This is the biggest reason to avoid tapered bearings. The original
ball bearings have shields to keep out swarf, but because of their
design, tapered bearings usually don't(never?) have shields.

The total cost is quite low (less than $35). Getting the last
bits correct is going to be a treat.

You may need to get another lathe to finish the work on this one---
Although that could be a good excuse... ;-)

RA

Geoff Steckel wrote:

I bought the Harbor Freight lathe and the advertised quick change
toolpost some months ago. The only way I've been able to use any
tool bigger than 1/4 inch is with the quick change unit, and only
then by lowering the tool holder well below the level of the cross
slide. It works, but it's not pretty.

After spending about 10 hours tightening every gib in sight,
polishing the ways, and other miscellaneous fixups, I am now
trying to replace the spindle bearings in hopes of getting
less play and flexing. The Harbor Freight model had straight
roller bearings, so I'm replacing them with angled bearings
to take thrust loads.

The stock bearings had about .8 mil static runout.
The dynamic runout was bad (> 5 mil, AFAIK) at speed.
We'll see if this improves it.

Michael Wood, Cincinnati" <michaelwood@...> wrote:

Can you give us the play by play on this modification? I'd like to know
how it turns out. Mike Wood

Will do - right now I'm trying to figure out how to load
the bearings properly. See below ->


"roylowenthal" <roylowenthal@...> wrote on
Sat, 30 Aug 2003 04:32:03 -0000:

The "standard" fix is to machine most of the "step" off the top of
the compound & some off the bottom. JWE has posted details, IIRC, in
the 7x10 files.

The 7x10 files? I must have missed them - I know about the minilathe
web site.
I was wondering whether that mod would weaken things too much.
Good to know that somebody has tried it successfully.

Are you sure about the bearings?

No, but it's the only thing left to try.

Bearing preload/end play is adjustable with the 2 nuts on
the geared end of the HS. Loosen the outer nut, adjust play with the
inner nut, tighten the outer (lock) nut against the inner nut.
Repeat as necessary to allow for the outer nut moving the inner nut
against its threads!

My lathe only has one nut, which was fully tight. The bearings are
simply pressed in and held with plates screwed onto the headstock.
This is why I'm being so drastic.

The HF I've got uses 6206ZZ bearings;
62 mm OD, 30 mm ID, deep groove ball bearing, double shields.

On reading about the deep groove bearings they really don't seem
to be able to take large axial loads. Better than the shallow ones
but not good.

I've spec'ed 30206M tapered-roller bearings from McMaster-Carr.
They turned out to be Timken. They're about 1mm wider than the
originals.
I will have to mill out the bearing seats slightly to clear the
outer roller ring.

One unpleasant surprise on removing the headstock was a large
pile of shavings from the unlubricated fiber-epoxy drive gears.
Not sure what to do here.

I got Belleville washers to apply pressure to load the bearings.
Also I intend to put felt discs in to hold oil and protect the
bearings from dirt. By adjusting the torque on one cover plate
I hope to load the bearings properly. I may have to machine a
new spacer to make the distances come out right.

Doing ASCII art for this was too much. See

for an attempt at a drawing.

The total cost is quite low (less than $35). Getting the last
bits correct is going to be a treat.

Geoff

Hi Geoff,

The mod to the compound rest is very helpful when you use a QCTP.
Since I don't have a mill I took advantage of the offering from LMS:


ProductID=1777

This mod reduces the height and also moves the pivot point which aids
in reducing chatter. Check the 7x10 group's messages for JWE's
suggestions on toolpost positioning vs the compound location. My
understanding of his comments is that the TP center bolt should be to
the right of the compound's pivot; the mod's re-positioned compound
pivot aids in achieving this (this mod idea was JWE's) while
maintaining good engagement of the compound's dovetail.

Ultimately, what you want is reduced overhang of the tool relative to
the compound -- using a QCTP tends to increase overhang so you must
then work around this. Its all about leverage - the farther the tool
point extends from the carriage the greater the chance of chatter.

One point with small lathes is that they are inherently not as rigid
as larger lathes so you must try to accommodate this reduced rigidity
in a number of ways, as you are doing.

Another thing which may be helpful is to grind tool bits to sharper
points rather than the rounded points suggested in many texts. The
broader the point the greater the forces generated which cause
flexing resulting in chatter. Sharp tools with good clearance angles
reduce the force generated by cutting rather than tearing the metal.

Having tried all the above I still get chatter sometimes, mostly when
facing steel and taking a light cut...

John

Here's a link to info on JWE's mod:



Frank Hoose


--- roylowenthal <roylowenthal@...> wrote:

The "standard" fix is to machine most of the
"step" off the top of
the compound & some off the bottom. JWE has posted
details, IIRC, in
the 7x10 files.
Are you sure about the bearings? The HF I've got
uses 6206ZZ
bearings; 62 mm OD, 30 mm ID, deep groove ball
bearing, double
shields. Bearing preload/end play is adjustable
with the 2 nuts on
the geared end of the HS. Loosen the outer nut,
adjust play with the
inner nut, tighten the outer (lock) nut against the
inner nut.
Repeat as necessary to allow for the outer nut
moving the inner nut
against its threads!

Roy
--- In 7x12minilathe@..., Geoff Steckel
<gwes@o...> wrote:

I bought the Harbor Freight lathe and the

advertised quick change

toolpost some months ago. The only way I've been

able to use any

tool bigger than 1/4 inch is with the quick change

unit, and only

then by lowering the tool holder well below the

level of the cross

slide. It works, but it's not pretty.

After spending about 10 hours tightening every gib

in sight,

polishing the ways, and other miscellaneous

fixups, I am now

trying to replace the spindle bearings in hopes of

getting

less play and flexing. The Harbor Freight model

had straight

roller bearings, so I'm replacing them with angled

bearings

to take thrust loads.

The stock bearings had about .8 mil static runout.
The dynamic runout was bad (> 5 mil, AFAIK) at

speed.

We'll see if this improves it.

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The "standard" fix is to machine most of the "step" off the top of
the compound & some off the bottom. JWE has posted details, IIRC, in
the 7x10 files.
Are you sure about the bearings? The HF I've got uses 6206ZZ
bearings; 62 mm OD, 30 mm ID, deep groove ball bearing, double
shields. Bearing preload/end play is adjustable with the 2 nuts on
the geared end of the HS. Loosen the outer nut, adjust play with the
inner nut, tighten the outer (lock) nut against the inner nut.
Repeat as necessary to allow for the outer nut moving the inner nut
against its threads!

Roy

Can you give us the play by play on this modification? I'd like to know how it turns out. Mike Wood

Geoff Steckel wrote:

Hi, all. I have crossposted this message to the following groups:

mwlatheideas, mlathemods, mlprojects, 7x10(&12)minilathe, Imported7x10minilathe

I hope this isn't considered a breach of etiquette. If so, I apologize in advance.

If you're still reading, here's my question: I remember reading a fairly involved thread some time ago regarding the use of a bicycle speedometer to display a lathe's spindle RPM. For some reason, though, I can't seem to find the thread(s) in any of the archives. I distinctly remember several messages explaining the method of calibrating the computer using both English and Metric measurements for spindle/chuck diameter.

Can anyone pierce through my thick skull and point me to the right info? I feel kind of silly not being able to find this for myself, but then again feeling silly is what I do best.

TIA,

- Russ



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I posted this in the 7x10 group but the OT noise was so high I think
it just got lost. Anyway, I've adapted an Enco 5" 3 jaw on my Micro
Mart lathe and it's nice to look at, but I can't turn much without
chatter. Actually, small diameter stuff (<1/4") and facing near the
work center is okay, but that's it. I think there's too much overall
flex in the spindle/chuck/work "assembly". My theory is that the 5"
chuck, being rather heavy at ~12 lbs, may deflect things downward.
Since turning produces upward forces that are probably irregular I
get vibration. I checked for looseness and dull bits but things
looked okay.

Has anyone experienced this problem and resolved it?

I made the backplate out of aluminum tooling plate and had no
problems turning it because, I think, it was close to the spindle
faceplate and has little mass.

Should I go to a steel backplate? How about turning one from one of
those disc shaped 5lb cast iron weights? More weight but more rigid.

Thanks,

Marc G.

Could someone please mention the latest number of Model Engineering?
I bought a subscription and it is to start with number 4196. Thanks!

First an observation which may be helpful. I haven't been doing
machining very long and can't make many contributions, but would like
to comment on my experiences with electrolytic rust removal. I picked
up an artical on this process a couple of years ago somewhere on the
tool collectors network and determined to try it. I do a lot of
woodworking and often come across good old tools which I would like
to use if they were not so rusty. It turns out that any old "dumb"
battry charger, preferably one with an ammeter can be used. I'd avoid
trying to use one of the new "smart" chargers which will sense the
batteries charge level and change their output accordingly. The
solution is just a mixture of Arm and Hammer baking soda in water.
The positive side of the charger goes to a scrap piece of stainless,
old pot lid or something, and the negative side goes to the rusty
tool. Both go in the solution about 2-3" apart. Turn on the charger
and watch them bubble. Average rusty piece takes about an hour for
me, and I keep the amps down under 5. It works great. The solution
does not have to be changed until it gets ickier than you can stand.
Please read the original documentation before you try it, just to be
safe.
Question. Just before I bought my lathe I purchased some 12L14,
6061, and brass 3/4" rod from Online Metals for practice material.
They have a nice service, but it seems a little expensive, and I
can't help thinking that there must be a simpler, cheaper way to get
metal to work with. I hear people talking about scrap yard purchases,
but I've never tried that. How will does just plain, garden variety
steel work for hobby machining? Has anyone had any experience with
their local scrap dealers? How should they be approached?
Thanks!

Just joined, again and reading through the posts. Saw this one.

I think someone else mentioned it, but I reckon DeltaCAD is the best
of the budget programs around. I use it instead of AutoCAD for basic
2D drawings.

EasyCAD is pretty good, but has got a bit bloated since its DOS days.

Getting around to getting the lathe soon, I hope. However, I would
like to use collets for holding small diameter material.

One solution is to use a milling collet but I would prefer a proper
lathe holder with a side key lock. The two I have found are for 5C
collets and ER25 collets. As the latter is half the price of the
former, and seems more suitable for amateur use, I was wondering
whether anyone had experience of either.

There is anther, but that costs more than the lathe!

Information is from Rotagrip (UK) catalogue.

Toolmex 5C collet Chuck - backplate fitting
Arrand ER25 Collet Chuck - Myford of Flange fittings
Pratt Burnerd that cost more than the lathe.

Personally I am looking at the ER25 solution as the collets
themselves could also be used in a milling machine.

Of course if it is easier on the small machine to use a milling tool
holder collet then that's fine. One holder for miller and lathe means
a few quid for something else.

Bill,

I would agree with your assessment of the tailstock, it is probably
not parallel in either plane. I was irritated with the tailstock
until I took a few hours to shim it between the two castings in the
various directions. (I don't have a mill so the more elegant
solutions were not available.) Using an MT3 center in the headstock
and an MT2 center in the tailstock, check the alignment with the
tailstock ram both extended and retracted. I ended up with about
.004" under the rear (horizontal shim orientation) and about .002" in
the front adjustment way (vertical shim orientation) to get it much
improved. Of course, now it is not readily adjustable for taper
turning, but I have no such requirement, and if the need presents
itself I will build a taper attachment which is a better solution.

Craig

--- In 7x12minilathe@..., "csfliers" <hkpsg@a...> wrote:

Also, I had to adjust my tailstock to get it more or less on center,
but I dont think I'd trust it for turning between centers. Im

willing

to bet the tail stock is off in 3 different axises.
I have been reading other posts, with people saying their machine

cuts

better than .001, so I figure my problems lay in my technique or
improper lathe setup.