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On Sunday 01 April 2007, born4something wrote:

Hi Vikki,

Ah, the dreaded broken tap. Every break is different and you do what
you need to do in your situation. It's always a good brain teaser.
In aluminium and brass I'm told alum is magical.

I'm going to try to track down some alum while I am out today just to
see if it actually works.

It sure does give one lots to think about, I'm pleased I just started
thinking rather than freaking out about it :-) :-)! Having some real
tools, even if smallish certainly opens a lot of doors in many ways.

I recently broke a 4mm tap in a 1/2" deep hole in steel. Chemical
techniques weren't going to help steel in steel. Attempts to grab
the little protruding portion just made it crumble. It was a good
hard tap. Like yours, it was my ninth hole in a row and I thought I
had the knack. They were going smoothly. Maybe the tap fatiqued as I
was not using much force.

Going for the 75% thread it was obvious the tiny tap was grunting down
neat the bottom of the hole. It is completely possible that the tap
could have been fatigued but I think that the real reason was that I
had the tap in the drill chuck mounted in the mill and was turning the
chuck by hand. My wrist got tired and I switched hands and am more
than a little sure I over torqued it at exactly the wrong time.

A while back I was asking (mainly out of academic interest) about
cutting O-ring grooves. Well, I've now cut my first O-ring groove
and a very tight face-seal type groove at that. I chucked the job in
the 4-jaw and got the broken tap on centre, confirming by peeping
through the spindle with a torch to see the reverse side. I then
ground a 1/8" HSS blank to a narrow grooving tool with heaps of
relief angle on one side to allow a really tight o-ring groove
around the broken tap. I cut a groove about 3mm deep about 1mm clear
of the tap. I then took skimming cuts at that 1mm thick island
around the tap. About one thou at a time until I was perilously
close to hitting the tap. A scriber was then poked down the tap
flutes to pry the thin remaining steel back. Instead of gripping the
tap with vice grips and having it crumble further I was able to
squash the end of some 1/4" stainless tubing to make the triangular
equivalent of a socker wrench. That distributed the load across all
three flutes and with a gentle back and forth motion I soon had
movement which gradually increased until I had it turning.

Sigh, it does appear impossible to get out, I futzed with it for a while
last night and tried several things. HSS tools just got screwed up
trying to turn it out and using carbide there was so much jump when the
tool contacted the remains of the tap that it accomplished nothing :-).
I was able to remove what was in the bore with the carbide boring bar
and the absolute slowest feed imaginable.

I finally was able to remove the raw edges on the outside with my
roomies lapidary diamond files (nasty surfaces poking out).

I could probably use the mill with one of the smallish PCB drills to
mill out around the tap without buggering the holder too much, but this
isn't real critical so the tap can just sit there. Other than as a
reminder, it isn't interfering with anything.

I did have some extra features on my finished product but it was
only a tool jig and I can live with that. It had toooo much work
invested to discard.

Same here, scrap isn't really available locally so everything is retail
priced. Worst case is that I turn it 45 degrees (eyeball, no indexers
or anything else, but it isn't real critical, I don't think) and remark
it for another set of holes, which I did last night.

Not sure if that helps your situation. But you can never have too
many solutions in the back of your mind!

Yes Sir, every little bit of kit that helps solve problems is always
welcome and a great addition to the mental toolbox :-).

Thanks & take care, Vikki.
--
Victoria Welch, WV9K/7
"Nothing can bring you peace but the triumph of principles." -- Ralph
Waldo Emerson

Ian,

How did you end up with a Real Bull in OZ?
I am not aware of anyone bringing them in.
I did toy with the idea of brining them in and converting them to CNC.
Even made contact with Ben at Real Bull and swapped emails.
Then I got married and plans changed:)

I am most interested in their CNC lathe as most of the other Chinese makers don't have any CNCed yet.

Gavin

From: "steam4ian" <fosterscons@...>
Reply-To: 7x12minilathe@...
To: 7x12minilathe@...
Subject: [7x12minilathe] Re: When is a Sieg not a Sieg? THE DIFFERENCES MATTER
Date: Mon, 02 Apr 2007 21:26:26 -0000

G'day Chris.
Thank you for getting back to me regarding Real Bull; as you may have
observed, I am full of it!
Seriously, it would be good if I and others could catalogue
differences as we come across them, eg key dimesions, feedscrew
diameters etc. It could save both you and your customers frustration.
Many of us have scraped together just enough for one lathe so can't
have a second machine to compare side by side, the only way we
discover changes is when buying replacement parts and finding they
have to be "addapted". I must admit it has made me hesitant to
lashout on upgrade parts.

I googled "china" "lathe" "manufacture" and came up with about 160
companies making lathes. I didn't get all the way through the list
but found at least 10 manufacturers of Mini Lathes, they were in
different provinces so I doubt they were were the same company. I
must admit in at least one case the machine was claimed by one
company but their picture showed a Real Bull logo on the control panel

It would be interesting to find where and how the design originated;
Chris, can you comment?.
I also suspect they are made for use in China and SE Asia for home
manufacturing (cottage industry) and not just for the hobby market.
They would be really good for this as thy could employ a family in
repetative small parts manufacture, better than starving. Even some
of the mini lathe parts could have been made by out workers on a mini
lathe.
An opportunity exists to aid struggling families in poverty areas of
under developed countries by providing them with a lathe. This
happens in India with sewing machines and pedal rickshaws where
charities exist to provide just such aid; they make an incredible
difference ("teach a man to fish and he will feed a village").

BTW, Thank you Chris for the service I have had from LMS and the
service LMS has provided to the craft and hobby.

One good turn deserves another.
Regards,
Ian

_________________________________________________________________
Join the millions of Australians using Live Search. Try live.com.au

G'day Chris.
Thank you for getting back to me regarding Real Bull; as you may have
observed, I am full of it!
Seriously, it would be good if I and others could catalogue
differences as we come across them, eg key dimesions, feedscrew
diameters etc. It could save both you and your customers frustration.
Many of us have scraped together just enough for one lathe so can't
have a second machine to compare side by side, the only way we
discover changes is when buying replacement parts and finding they
have to be "addapted". I must admit it has made me hesitant to
lashout on upgrade parts.

I googled "china" "lathe" "manufacture" and came up with about 160
companies making lathes. I didn't get all the way through the list
but found at least 10 manufacturers of Mini Lathes, they were in
different provinces so I doubt they were were the same company. I
must admit in at least one case the machine was claimed by one
company but their picture showed a Real Bull logo on the control panel

It would be interesting to find where and how the design originated;
Chris, can you comment?.
I also suspect they are made for use in China and SE Asia for home
manufacturing (cottage industry) and not just for the hobby market.
They would be really good for this as thy could employ a family in
repetative small parts manufacture, better than starving. Even some
of the mini lathe parts could have been made by out workers on a mini
lathe.
An opportunity exists to aid struggling families in poverty areas of
under developed countries by providing them with a lathe. This
happens in India with sewing machines and pedal rickshaws where
charities exist to provide just such aid; they make an incredible
difference ("teach a man to fish and he will feed a village").

BTW, Thank you Chris for the service I have had from LMS and the
service LMS has provided to the craft and hobby.

One good turn deserves another.
Regards,
Ian

There is a book called "The Amateurs Lathe" by Sparry that covers
almost every aspect of practical lathe work. It is an old book (circa
1950) but still easily available here in the UK. The other book I
would recommend is "The Amateurs workshop" by Ian Bradley. This
covers all workshop tools lathes, drilling machines,drills, taps,
shaping machines, milling, compressed air,paint spraying, soldering
and brazing. This is also old book but full of basic practical
information on workshop practice. This is also readily available in
the UK.
I hope this is useful
Kind regards
Mike
Kingsley, UK

--- In 7x12minilathe@..., "rroll99" <rroll99@...> wrote:

I was wondering if the group has a consensus about what would be a
good book for someone who wants to not only learn how to use a

lathe,

but also how to properly layout, cut, drill, tap, grind bits and do
other basic machine shop operations.

I just bought Frank Marlowe's "Machine Shop Essentials" and it does

a

great job of explaining terminology and showing tools and methods.

But

I'm looking for a book that has more practical tips and how-to's for
someone who is just starting to learn this craft.

I'd prefer to have a book to keep near my work bench, but I'd also
love to hear about any good web sites or downloadable files.

BTW, I bought a Homier 7x12.

Thank you,

Rob

You might try going to your local high school or Community Colleg that offers Machine Shop Technology courses, and see what books they use. Perhaps you could buy a used one, especially from a college bookstore. Good luck, Ron. Keep makin' chips!


---- rroll99 <rroll99@...> wrote:

I could not get it, either.
Thanks, Ron.


---- jumbo75007 <fullerdj@...> wrote:

Dan,

It's not you, its the web page. The img is a broken reference. Use
your imagination. It is simply a large knurled disk that is 'clamped'
to the tap. The disk is 1 1/8" diameter and 0.325 thick. The drill
chuck is slightly loosened so the user can turn the tap using the
knurled disk (ie. the Tap Disk). This gives the operator a
better 'feel' of the force turning the tap. Easier to feel how tight
it is getting. The drill chuck is used as a centering device to make
sure it goes in straight. HTH. :)

Rance


--- In 7x12minilathe@..., "jumbo75007" <fullerdj@...>
wrote:

Well if it is not one thing it is another..........
I now found the tap article, but the picture will not come up on my
Internet Explorer. Would some one down load the picture and send

it to

me.
Thanks,
Dan Fuller
Carrollton, Texas
fullerdj@...


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

Try


--- In 7x12minilathe@..., "Bill Kenny" <billcnc@>

wrote:

Bob,

For some reason, it is not showing up in the search. Do you

have a

more

refined link?

Thanks
Bill

Well if it is not one thing it is another..........
I now found the tap article, but the picture will not come up on my
Internet Explorer. Would some one down load the picture and send it to
me.
Thanks,
Dan Fuller
Carrollton, Texas
fullerdj@...

I was wondering if the group has a consensus about what would be a
good book for someone who wants to not only learn how to use a lathe,
but also how to properly layout, cut, drill, tap, grind bits and do
other basic machine shop operations.

I just bought Frank Marlowe's "Machine Shop Essentials" and it does a
great job of explaining terminology and showing tools and methods. But
I'm looking for a book that has more practical tips and how-to's for
someone who is just starting to learn this craft.

I'd prefer to have a book to keep near my work bench, but I'd also
love to hear about any good web sites or downloadable files.

BTW, I bought a Homier 7x12.

Thank you,

Rob

Try


--- In 7x12minilathe@..., "Bill Kenny" <billcnc@...> wrote:

Bob,

For some reason, it is not showing up in the search. Do you have a

more

refined link?

Thanks
Bill

Ian:

Mini Lathes with a rectangular carriage (as opposed to an H-shaped
carriage) are not made by SIEG. In most cases they are made by the
Yangzhou Real Bull Machine Tool Co. As you have found, there are
differences.

All the mini lathes sold by major vendors in the US are currently made
by SIEG. The "Real Bull" company seems to have better traction in other
parts of the world.

Regards,
Chris Wood

LittleMachineShop.com <>
The premier source of parts and accessories for mini lathes and mini
mills.
396 W. Washington Blvd. #500, Pasadena, CA 91103
(800)981-9663 * Fax (626)797-7934


________________________________

From: 7x12minilathe@...
[mailto:7x12minilathe@...] On Behalf Of steam4ian
Sent: Friday, March 30, 2007 9:23 PM
To: 7x12minilathe@...
Subject: [7x12minilathe] When is a Sieg not a Sieg?



G'day all.
I recently told you of my testing of the leadscrew mechincal fuse, it
works!. Yes, I damaged the 80T gear. Thankfully it is not beyond
recovery, so that it is now in the tuit basket.
I had previously purchased a spares kit from LMS and this morning dug
the replacement 80T gwear out of the bag. Surprise! the key way is
3mm wide not 4mm as for my lathe. I know my key is 4mm because a few
weeks ago I dropped my key in the swarf (on the floor I thought) No
amount of grovelling could find it so I grabbed a MS tent peg and
milled a new key; actually I used a file. BTW I found the key hiding
under the control box this morning.
I recently got an idler sleeve and key from LMS only to find tha the
key on that is 3mm as is the replacement LS key I purchased. The 57T
& 65T gears I purchased from LMS also have 3mm keyways whilst the
gears that came with the lathe have 4mm key ways. Thankfully a file
can address most of the problems. I can probably file a T profile key
for the sleeve, 3mm one side and 4mm the other.
The QUESTIONS:-
When and how did the change occur? My lathe has similar features to
the yellow Cummins, eg, square not H shaped saddle, way wipers, ball
oilers, nut on RH end of lead screw, etc. Some much earlier posts
commented that the yellow Cummins lathe was not made by Sieg.

Have others with yellow Cummins or Chestern Conquest lathes had the
same experience? The present Cummins lathe is blue and the pictures
don't show the features I refer to.

Have you found other dissimilarities?

Maybe Chris of LMS is lurking so he could comment?

Finally, why are Tuit baskets square??

One good turn deserves another.
Regards.
Ian

Bob,

For some reason, it is not showing up in the search. Do you have a more
refined link?

Thanks
Bill

Here's a link to another nifty tap alignment jig:


Taps break for several common reasons:

1. Misalignment with the hole - the jigs solve this so the tap doesn't
run into the side of the hole as it goes deeper.

2. Dry tapping - WD40 works well on aluminum, cutting oil on most
other things. Cast Iron doesn't need fluid.

3. Dull tap - taps turn hard to let you know they're dull. Often this
means a tooth is chipped, usually near the end - a little careful
grinding will make it into a nice bottoming tap :-)

The gun taps seem to work better for me than regular taps, especially
on through holes. Probably because they push the chips forward rather
than collecting them in the flutes, no need to reverse direction to
break chips. On blind holes I run the tap in until it gets hard to
turn, back it out, clean the chips out, and run it in again to finish
the bottom threads (or use a bottoming tap). Gun taps work
particularly well for sizes #10 and smaller.

John



--- In 7x12minilathe@..., "charlie4_66043" <radfordc@...>
wrote:

Using small taps freehand is guaranteed to break them. I now use a
device called a "tapdisk" and never break taps....hardly ever (don't
want to jinx myself).

I found the instructions for making the tapdisk here:


"TAP DISK
Difficult to believe that I have not posted a tip about my Tap Disk.
Every shop should have one , and use it, to prevent small tap
breakage. I have not broken a tap within the past 10 years while
using my Tap Disk and I constantly use tap sizes 0 through 6. Take a
few minutes to make one, try it and I am sure you will opt for this
taping method whenever possible.

THE DISK
Turn an Aluminum disk, 1 1/8" OD, knurl it, center drill .144" and
part it off .325" thick. Drill NO. 43 from the OD to the ID and tap 4-
40. Install a 4-40, hex head bolt, .750" long.

TO USE
Insert the tap in the Tap Disk to it's mid point. Tighten the bolt
with a 1/4" wrench. Drill the hole to be taped in the Drill Press,
Mill or Lathe. Remove the drill, fill the hole with WD-40, or your
favorite taping fluid and grip the upper half of the tap in the
chuck, just loose enough to turn freely. Lower the spindle/tap to the
work. Use your thumb and forefinger to tap the hole. The photo below
shows the Tap Disk ready to use.
Bob Shores
Ruskin FLA"



--- In 7x12minilathe@..., Victoria Welch <wrlabs@>
wrote:

Just to share the fun.

Got my laser edge / center finder holder all turned and bored out

and

started drilling and tapping (4-40) for the set screw / power

switch

holes. Went along nicely up until the final one (9th) where the

tap

broke.

Nothing gets it out :-(. And of course it is one of the lower
(critical) ones :-).

I tried the 4-40 tap out of my little kit from the auto parts place

and

it promply turned itself into a corkscrew :-). Broke too, but it

was

soft enough not to shatter and I was able to get it out with vice
grips.

Sigh. I suppose that this isn't a real big deal since this is

a "proof

of concept" thing and I can rotate the holder 45 degrees and put in

a

new set.

Lessons learned: When wrists get tired from doing the tapping -

take a

break rather than switch hands and cheap taps are a total waste of

time

and money (now I know what a cheap tap is :-).

Only a minor setback as I now have the holder itself worked out and

can

easily enough duplicate it.

Not a bad day!

Take care, Vikki.
--
Victoria Welch, WV9K/7
"Windows, another fine product from the folks who brought you

edlin." --

Unknown

G'day Viki, John.

You have found the difference between cheap taps and better quality
taps.
I have about three sets of "cheap taps". The other day i was
attempting to cut a 8mm thread in an SS bush. The cheap taps just
would not look at the job. Fortunately I had purshased a limited
selection of Brand name taps, not top of the range but good. I
extrated ane of the better taps from its packet and set it to work.
The job was almost effortless. Forget the cheap taps unless you want
to cut a thread in
lead. As for cheap dies, I get a better job on the lathe.

I have struck it lucky with one set of truly bargain taps. A tooling
store had relocated to near my home and must have bundled eveything
together in the move and then couldn't be bothered sorting through
it. I picked up a 3/8 x 24T set of taper, plug and bottoming taps for
AUD3.00 plus some other goodies like reamers for AUD5.00.
If any one in Oz wants me to look for a specific item let me know,
you could get a bargain. There's taps and dies of odd sizes, reamer,
milling cutters (horizontal) etc.

I must have done somebody a good turn!
Regards,
Ian

Using small taps freehand is guaranteed to break them. I now use a
device called a "tapdisk" and never break taps....hardly ever (don't
want to jinx myself).

I found the instructions for making the tapdisk here:


"TAP DISK
Difficult to believe that I have not posted a tip about my Tap Disk.
Every shop should have one , and use it, to prevent small tap
breakage. I have not broken a tap within the past 10 years while
using my Tap Disk and I constantly use tap sizes 0 through 6. Take a
few minutes to make one, try it and I am sure you will opt for this
taping method whenever possible.

THE DISK
Turn an Aluminum disk, 1 1/8" OD, knurl it, center drill .144" and
part it off .325" thick. Drill NO. 43 from the OD to the ID and tap 4-
40. Install a 4-40, hex head bolt, .750" long.

TO USE
Insert the tap in the Tap Disk to it's mid point. Tighten the bolt
with a 1/4" wrench. Drill the hole to be taped in the Drill Press,
Mill or Lathe. Remove the drill, fill the hole with WD-40, or your
favorite taping fluid and grip the upper half of the tap in the
chuck, just loose enough to turn freely. Lower the spindle/tap to the
work. Use your thumb and forefinger to tap the hole. The photo below
shows the Tap Disk ready to use.
Bob Shores
Ruskin FLA"



--- In 7x12minilathe@..., Victoria Welch <wrlabs@...>
wrote:

Just to share the fun.

Got my laser edge / center finder holder all turned and bored out

and

started drilling and tapping (4-40) for the set screw / power

switch

holes. Went along nicely up until the final one (9th) where the

tap

broke.

Nothing gets it out :-(. And of course it is one of the lower
(critical) ones :-).

I tried the 4-40 tap out of my little kit from the auto parts place

and

it promply turned itself into a corkscrew :-). Broke too, but it

was

soft enough not to shatter and I was able to get it out with vice
grips.

Sigh. I suppose that this isn't a real big deal since this is

a "proof

of concept" thing and I can rotate the holder 45 degrees and put in

a

new set.

Lessons learned: When wrists get tired from doing the tapping -

take a

break rather than switch hands and cheap taps are a total waste of

time

and money (now I know what a cheap tap is :-).

Only a minor setback as I now have the holder itself worked out and

can

easily enough duplicate it.

Not a bad day!

Take care, Vikki.
--
Victoria Welch, WV9K/7
"Windows, another fine product from the folks who brought you

edlin." --

Unknown

Hi Ian,

I'd be talking more to Uncle Rabid before looking to buy a new
board. He's the local oracle and repairs them for a living. He's
strangely generous with his advice around here given that he could
just play his cards close and boost his business. I think he
actually likes being helpful! If he can't talk you through he'll fix
it for you for a pretty reasonable fee anyway.

The other reason for running things past Uncle is that he deals with
most (all?) the variants on these controllers. Most of us only
experience one or two of them. Some are FET based and others SCR.
Some use relays and others don't. Mine has no relays but those 5-pin
blocks are sounding like 24V coil relays. Two for the coil and three
for the changeover contact set.

John


--- In 7x12minilathe@..., Ian Fletcher
<ian.fletcher@...> wrote:

Hi John, thanks for the warning. I was unable to get a reading off

the second resistor so have ordered two. Visually I cannot find any
damage to the board or components apart from what looks like
mechanical damage to one of the two square yellow blocks marked
HR54H-S-DC24V which seem to have 5 legs, which I take to be voltage
convertors? As you can see although capable of soldering and
unsoldering small components I am not always able to identify what
they are!! If I do need to bite the bullet and buy a new board are
they all the same from different manufacturers? I know Clarke lathes
are more expensive that others and wondered if the circuit board
would be cheaper from other makers. Thanks Ian

-----Original Message-----

From: born4something <ajs@...>
Date: Sun Apr 01 08:02:37 GMT 2007
To: 7x12minilathe@...
Subject: [7x12minilathe] Re: circuit board diagram

Hi Ian,
Just a thought. Might not be what you want to hear. If only one
resistor is burnt out and they are in parallel as a 0.33 ohm for
current sensing then the machine should run, but overload sense

at

half load. So either BOTH resistors have failed or there is
something else failed too.
John
--- In 7x12minilathe@..., Ian Fletcher
<ian.fletcher@> wrote:

Thanks for advice, resistors ordered at cost of ????1 so if

that is

all that is wrong I shall have saved ????84 !! Thanks for your
interest and support. Ian

-----Original Message-----

From: born4something <ajs@>
Date: Fri Mar 30 08:07:03 GMT 2007
To: 7x12minilathe@...
Subject: [7x12minilathe] Re: circuit board diagram

Hi Ian,
66 ohms sounds a bit high. You may have tricked people with

that

space between the R and 66. Electronics types often use the

prefix

as a decimal point (like 1k2 means 1.2k-ohms) and when there

is

no

prefix they just insert the base symbol, R. So R66 is likely

0.66

ohms. It's a convenient notation and avoids using those

little

dots

that don't print clearly and are often multiplied when

photocopying

stuff!
Check the other resistor. If it is 0.66 ohms I'd expect

quite a

reasonable reading in circuit without even unsoldering it as

the

surrounding components are unlikely to be anywhere near as

low

as

that. If they are, it's likely a failed FET or triac,

depending

on

your model.
John
--- In 7x12minilathe@..., andrew franks

<andyf1108@>

wrote:

Looks as though it might be: 5W = 5 watts, R66 = 66 ohm.

Not

sure

about the J, though - could represent a tolerance (as in

plus or

minus a certain percentage from the marked resistance

value).

However, 66 ohms isn't a standard "preffered" value - 68

ohms

is,

though. Can you unsolder its twin, if it has identical

markings,

and

check it? If it is 66 ohms, you may have to use a couple of

33

ohm

ones, and connect them in series (though if you use 68 ohms,

it's

probably close enough).

As to wattage, if you can't get 5 watts from Maplin or

somewhere, get the next size up.

I wonder what made it burn out, though? Hopefully, it

was

something simple like a short circuit caused by swarf.

Andy
ftr1d <ian.fletcher@> wrote:
Hi, I have just purchased a 240 volt Clarke 300m

with a

dead circuit

board. A new board will cost ????85 so I am looking to

repair

it. The

only

fault I can see is a blown ceramic block, one of a pair,

which

is

marked 5WR 66J and is in R1 position on the board. I

assume it

is

a

creamic resistor? Does anyone have a circuit diagram or

can

give

me the

specification of the part. Thanks Ian






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G'day Gerry.

Thanks for the reply. I like the Nyloc nut idea, I must pick some nuts
up from the auto parts shop. To make the dial locking more flexible I
turned some small aluminium pellets, 5mm dia. by 3 mm long and put one
of these in the bottom of the hole. Now I can have the dials firm but
can turn them without scoring the shaft.

As I wrote I am sick of the inch to metric conversion as from time to
time I get it wrong. Over the next few weeks I'll get around to doing
the dials.

One of these days I'll make something which doesn't actually go on the
lathe!

One good turn deserves another.
Regards,
Ian

Take a look at Vicki Ford's site through the link on www.mini-lathe.com.
She made two very nice QCTP's from Aluminium, both clamp and piston trpe using steel insert for the threads

gerry
Leeds UK

From: "rancerupp" <rupps@...>
Reply-To: 7x12minilathe@...
To: 7x12minilathe@...
Subject: [7x12minilathe] Re: Shim Screw Tool Post (SSTP)
Date: Sat, 31 Mar 2007 19:32:53 -0000

Thanks Ron. So how about using threaded inserts in an aluminum block?
First downside I see with an insert it creates an additional place
for possible lost rigidity. I've seen Pem Nuts for 6-32 screws in
1/16" alum. pate. Has anyone seen similar for 3/16 or 1/4 inch bolts?
T-Nuts come to mind, but those are for wood. If the threads are the
only forseeable problem, then I'd prefer to use alum.

As for rigidity, my toolpost is 2 3/4 square and 1 5/8 high. Top lip
is a bit over 1/2, the middle slot is about 3/4, the bottom lip is a
bit over 1/4. The middle slot is about 1/2 in from the outer edge.
With that, the shortest threaded insert would be for the bottom
(1/4").

Good point about shimming the sides. I have some ideas on that but
I'll wait before introducing those.

Anyone know of sources for threaded steel inserts? Thanks.

Rance


--- In 7x12minilathe@..., <trainguy_347@...> wrote:

Hi, Rance. Aluminum (aluminium) is strong, but it has been my

experience that threaded holes are easily stripped or deformed with
twisting motions. Steel would probably be best. As for the stability,
try using a shimming block against the inside vertical surface of the
tool, between it and the tool post. Good luck, Ron.

---- rancerupp <rupps@...> wrote:

Thanks Ron, and to Clint for posting the pics.

Ron, others, would you think that al. would be sufficient for

this or

does it have to be steel? The toolpost that comes with the 8x12

seems

huge. I would think that an alum. one of the same dimensions

would be

fine.

Also Ron, did you have any problems with the mounted tool bit
twisting while using your set screw configuration? Clint had
expressed concern of rigidity.

Rance


--- In 7x12minilathe@..., "Ronald Durbin"
<trainguy_347@> wrote:

I have done this with a smaller post, except that
I used set screws (or grub screws, as our British brothers and

sisters

call them) comming up from the bottom. To adjust, just undo the
retaining nut on top, lift up the post, back off the top screw
slightly, engage (run further in) the bottom screw tightly, and
replace the post as per normal. This sometimes take a few

tries,

but

once the height is achieved, all is well. Great drawings, by

the

way!.

Ron.

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Hi Ian

I too have a Real Bull Machine marketed and sold here in the Uk by Warco as their "Mini-lathe"

I have had it for three years and it has proven to be very reliable. One other difference from the Seig mini is that the dial locks are by small allen screw which are tightened onto the shaft and these are not as convenient as the spring clip on the Seig. the first thing I used the machine for was to make some small 5mm knurled aluminium screws for the dial adjustment and this has worked fine since.

Another was to get rid of the two adjusting screws and to replace with a single "Nyloc" nut which makes backlash adjustment much simpler.

Gerry
Leeds UK

From: "steam4ian" <fosterscons@...>
Reply-To: 7x12minilathe@...
To: 7x12minilathe@...
Subject: [7x12minilathe] Re: When is a Sieg not a Sieg?
Date: Sat, 31 Mar 2007 08:04:11 -0000

G'day all.

My machine may be a Real Bull, which may explain many of my posts!

More variations. The RBM machine (probably mine) has two lock nuts on
the compound feed screw to provide adjustment of the bearing
backlash??? They bear on the dial and so effect that as well.
This also may explain why the 50 division dials I bought from LMS
don't fit. The internal diameter is 12mm whilst my feedscrew shafts
are 10mm diameter.
The fix will not be difficult. For the cross slide I intend to turn
up a bush, 10mm internal and 12mm external make a saw cut along the
bush. I can cross drill and tap the dial 6mm (as per my existing
dial) and use a set screw to adjust the friction with the shaft. For
the componud I can make a similar bush but with a collar at the
inboard end. The dial can also be cross drilled and also have a
recess for the collar of the bush bored out, the existing lock nut
can press against the outboard end of the bush.

Why the 50 div dials? because I work in metric and the Thou divisions
are a pain, you have to calculate for evey adjustment.

Please join the game of "spot the difference."

One good turn deserves another.
Regards,
Ian

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Hi John, thanks for the warning. I was unable to get a reading off the second resistor so have ordered two. Visually I cannot find any damage to the board or components apart from what looks like mechanical damage to one of the two square yellow blocks marked HR54H-S-DC24V which seem to have 5 legs, which I take to be voltage convertors? As you can see although capable of soldering and unsoldering small components I am not always able to identify what they are!! If I do need to bite the bullet and buy a new board are they all the same from different manufacturers? I know Clarke lathes are more expensive that others and wondered if the circuit board would be cheaper from other makers. Thanks Ian