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From: Robert Bastow <teenut@home.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Lathe Bed Grinder
Date: Wed, 13 Oct 1999 18:41:29 GMT

Marshall Pharoah wrote:

> I just purchased a 13" South Bend for the exorbitant fee of $310, and
> there is some noticeable wear under the carriage.

NO!!

The SOB,s ripped you OFF!

Just kidding Marshal..At that price it is worth putting some serious work into
rehab.  (The LATHE..Silly!)

Before going to a heap of trouble trying to regrind the bed yourself..iffy
proposition at best 8^{..You might want to investigate the possibility of having
it reground professionally!

It is NOT as expensive as one might imagine..Rebuilding companies with bedway
grinders to keep running are glad of the business and you can usually cut a
deal.  Heck, they can regrind a bed, that size, in half an hour..Floor to floor!

What IS expensive, and what often kills the Idea, is the transportation to and
from the Grinders.  Usually more than the grinding cost.

However, you are fortunate in being located in the North east.  I am
guessing..but I'll bet 75% of the way grinders in North America are located
within a day's drive of you!

Time to hit the Thomas Directory.  8^)

When you have the ways ground..tell them you are going to fit turcite linings
(Beats the heck out of scraping!!) and ask them to take enough off and to leave
you a suitable finish..No, NOT dead smooth, a cross hatch grind is much better!
The waygrinders usually use cup wheels..like a miniature Blanchard grinder.

Have fun!

teenut


From: Robert Bastow <teenut@home.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Lathe Bed Grinder
Date: Thu, 14 Oct 1999 05:29:08 GMT

Turcite isn't really expensive in the small areas and thicknesses required for a
Southbend sized lathe.  I doubt you need more than 6 or 10 square inches, and
1/32" or 1/16" maximum thickness.  The epoxy they sell is pricy..but there are,
nowadays, other sources of epoxys that will do the job.

Re-furbishing a lathe with turcite ELIMINATES the need to drop the saddle or
raise the feed shafts etc.  The Idea is to remove enough metal from the bed to
clean it up, and then mill enough off the saddle, not just to clean it up..but
to bring it back to exactly the same place it was when new...After you interpose
a layer of Turcite of the required standard thickness.

No scraping of the saddle is required!  The Turcite and epoxy are alowed to
adhere and set, without applying any pressure and while the saddle is
temporarily shimmed to the right height and level.  Once the Turcite has
adhered, then a very light spottin and scraping can be done..if required.  If
the epoxying  is done carefully...no "post scraping" should be required.

Applying Turcite will absolutely transform any lathe.  Firstly it virtually
eliminates "stick/slip". Secondly, you can snug up the retaining gibs,
literally, to "negative clearance". That, and the natural tendancy of Turcite to
deaden vibrations, means that chatter will be virtally eliminated.

IMHO, having read, frequently of various ways that people have reground their
own beds, using a variety of ingenious, but convoluted methods..any accuracy
remotely approaching the accuracy of a new lathe..or a proper regrind..is PURELY
ACCIDENTAL!

I don't care how you care to figure it...using the tailstock ways to grind the
saddle ways because they are "less worn" than the saddle ways..is a crock of the
first order.  However you run the trig..using a less than PERFECT guiding
reference to generate another one.will MULTIPLY, not decrease the original
errors!

Of course, when you have ground your ways until they look nice and shiny, and
you have twisted your lathebed so you can barely detect a taper (can you say
sway or swell?), then I guess it is easy to convince yourself, not to speak of a
casual, awestruck,observer, that you have indeed made it "as good as new"!

I wonder why Professional Rebuilders don't do it that way?  They could bring a
portable rig and regrind your lathe bed while you nipped out to lunch.  I bet
they just haven't thought of it yet, Huh?  8^)

A decent lathe deserves better..even if that means hand scraping the whole
thing.  Of course then a decent set of scraping masters and references will case
more than a professional regrind.

teenut


From: Robert Bastow <teenut@home.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Lathe Bed Grinder
Date: Thu, 14 Oct 1999 07:37:34 GMT

mulligan@advinc.com wrote:

>   Robert Bastow <teenut@home.com> wrote:
>
> > It is NOT as expensive as one might imagine..
>
> I have seen this topic go 'round the ng for years.  But I have
> never heard the final message that said, 'yes, I got the
> bed ground *here* for X dollars, and they will do yours for
> the same.


I guess it is time for me to "Put Up or shut Up"  8^o

The last lathe bed I had reground was in about 1983. It was a Smart & Browne
Model A  10" x 24"

The grinding was done in Cambridge, Ontario and cost IIRC about Can$125.00 at
the time. I drove up there, with the bed, from Stoney Creek, and watched and
waited while they did the job.  It took less than an hour!

I can't remember the exact name of the outfit that did it, and I don't know if
they are still in business...But the name Cambridge Machine Tool Rebuilders rigs
a faint bell

I was able to scrounge enough advice, scraps of turcite and a big enough "Dip"
of their epoxy pot to line the saddle ways for free.

I re-machined the saddle ways, taking them down far enough, that when I epoxied
on the 1/16" Turcite, it brought the saddle back to precisely the right height
for the lead screw and feed shafts to slip easily back into the new bronze
bushings I fitted.

I could have chosen to do the Saddle milling at the machine shop I was managing
at the time, or I could have taken it to the local Vo Tech, where I was a member
of the Board of Advisors.

However, that would have meant two trips and two setups, because it was
necessary to first machine the saddle ways to clean and level. Then I had to
assemble the saddle to the bed with shims in place, to determine PRECISELY how
much more I needed to take off to bring everything back to the right place when
the Turcite was glued on.

IIRC the grinders took off about 0.008" to get the (Hardened) bed back to dead
true.  They ground it with a cup wheel, leaving a criss-cross pattern that is
best recommended for turcite.  The tiny hatching provides for oil retention and
reduced friction in exactly the same way that scraping or frosting does.

I chose to do the machining at home, on my home made, hand cranked planer. This
I had made from a 36" Standard Modern lathe bed (factory rejects turned up
regularly at the local scrap yard). The table was 24" x 14"  IIRC a tee slotted
table from a Deckel or Gorton Diesinker. The bridge and uprights were machine ON
the machine by ingenious and/or devious means.

The feed screws and nuts were "Liberated" a few years earlier, from the spare
parts inventory of Alfred Herbert (Canada) as reparations (partial) when they
closed down owing all the employees at least two month's wages and any and all
severance pay, bonuses, commissions and expenses!!!

Drive was via rack and pinion, directly connected to a VERY heavy 14" diameter,
six spoked, cast iron handwheel that once graced the saddle of a huge old center
lathe!  The tool slide came from an old shaper as did the downfeed screws and
clapper box.  Eventually it was graced with a Bridgeport M Type head that I
"won" from a guy that couldn't pay me for a job!

Thus it became a "Planer Mill" and went on to do sterling service..the first
job, (and the reason it was built) was to re-manufacture a $25.00 "basket case"
of a Myford Super 7.  I had to plane and scrape, over 75 thousandths of an inch
off the bed to straighten out wear and the depredations of a previous
"Restorer"  Eventually that Myford was rehabilitated to become a better, more
accurate machine than its makers ever dreamed of (It had turcite linings too)
The entire saddle was missing so I scratch built a new one and fitted it with a
rebuilt cross slide and compound from an old Hardinge lathe.

The only "Boughten" parts were a new lead screw and nuts which cost four times
as much as I had paid for the rest of the Lathe!!  Eventually I sold the Myford
for over $2000.00..to a fellow member of TISME who couldn't wait to write a
check!!

As usual I digress..But I did want to establish a bit of credibility, when it
comes to talking about lathe reconditioning. (Coincidentally I do have
photographs of the Planer and the two lathes..If anyone is interested I will try
to figure how to get them on my new web page. (Where the heck IS that son of
mine when I need him?)

Moving right along...When I got my Maximat a couple of years ago, it was (still
is) my intention to give it the Turcite treatment..even though it has no
measurable wear on bed or saddle!  Once you have used a lathe with turcite lined
ways, you will never be satisfied with less.

So, about a year ago, I tracked down (and befriended) the local Turcite Rep.
(FIND YER OWN!!!) which resulted in an accumulation of enough "Evaluation
Samples" to do the job!  8^)  (Hey..Haven't you noticed how NICE I am to people
all the time!)

I also made several inquiries regarding regrinding the bed. No it probably
doesn't NEED it but if I am going to all that trouble it will be done RIGHT!!
If for no other reason, than that cross hatch patern IS important.

There is no one in the south east that knows what a way grinder is (Dammit, or
even a lathe for that matter!!) But I was able to talk to a couple of shops in
the North-East (Philly. New Jersey etc.) and the median ballpark was under
$300.00.  Unfortunately it would cost almost as much to ship...EACH way!!  So,
as it is not a priority, it may wait a while..but one of these days...!

I didn't even keep a note of who was chea..least expensive!  I was content to
know that, when the time comes, finding someone to do it won't be a problem.  I
will just bite the bullet and suggest a leisurly motoring vacation to my lovely
Southern Wife..who has never low...who has never been so lo..far north..as the
Mason-Dixon!!  Oh Honey.. by the way..being as we are going to...

Yes the bed will fit in the trunk of the Jag..I measured it!

8^)

teenut


From: Robert Bastow <teenut@home.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Lathe Bed Grinder
Date: Thu, 14 Oct 1999 13:20:16 GMT

In that case..you have it made!!

A lot of "Bedway Grinders" started out as planers.  Even the custom built ones
bear a remarkeable family resemblance. The big ones are double column with a
bridge, more modern ones are like an openside planer.

Kit it out with dust protection for the ways, a tool post grinder and a flaring
cup wheel and you could even go into the bedway grinding business!

 When can you do mine..for free of course! I'll bring the beer. Eh! :^o

teenut

Marshall Pharoah wrote:


> But, I do have a cousin that has a huge old Brown and Sharpe planer with
> a J head to go on it.


From: Robert Bastow <teenut@home.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Lathe Bed Grinder
Date: Thu, 14 Oct 1999 15:12:25 GMT

I can't disagree with you on a single point Jim. Except where to go (come) for
free Turcite.  (MINE I tell you...all MINE!!)  8*)

HSMs and Commercial Operators inhabit different worlds.  Had that been one of my
Business's money making machines, one of two things would have happened
(actually I would never have bought it in the first place :^)

After a careful ROI analysis, it would how been sent off to be rebuilt at a
fixed, quoted price, and on a strict delivery schedule.  Or it would have been
traded in on a new one. Period!  The other alternative, still followed by too
many, of keeping a clapped out machine around for the occasional odd job, is not
an option any more.

Indeed, rebuilding would only be undertaken under fairly unique
circumstances..take our big old planer for instance.  No way could it earn its
floor space as a planer.  But remanufactured, fitted with modern drives,
controls and modular,high powered milling heads, it could possibly justify a
$200.000.00 investment, if the alternative were a million dollar Floor Borer!
Made in Russia, Poland or China!!

On the other hand, with my HSMers hat and teeshirt ("Machinists wash their hands
BEFORE using the Bathroom"..  Replete with simulated oil slart over left
front)...I can perhaps help some other HSMer to find a way to get the kind of
rebuild done that he would really prefer..and not be stopped by a pre-concieved
notion that it is too difficult or expensive to do it right.

In actual fact, were I faced with the need to regrind my own lathe bed, i would
hi me to the nearest scrap yard and see if I couldn't scare up the makings of
another Plainer/grinder!

With a fixed bridge, hand feed and a lot of patient chipping, filling, shimming
etc, A real good end could result, independant of whatever "Residual" accuracy
might be left in the lathe bed itself,

If I found myself stuck, with no alternative, I would reference fom the
untouched portions of the bed..the narrow lands beteen the ways..rather than the
tailstock guide ways.

Incidentally, I just "Won" a pair of ex aerospace reference parallels, on Ebay
for less than forty bucks.  These are 30" long x 1 1/4" x 3" stabilised and
precision ground.

This is my back-up reference and potentially a set of precision guide rails if I
ever do need to regrind my own lathe bed.

teenut




mulligan@advinc.com wrote:
>
> In article <38058922.9C9619C9@home.com>,
>   Robert Bastow <teenut@home.com> wrote:
>
> > As usual I digress..But I did want to establish a bit of credibility,
> > when it comes to talking about lathe reconditioning.
>
> Not really in doubt.  But your posting of your experiences
> sort of proves my point - the average hsm will not be able
> to call in as many favors, nor will have the resources available
> in terms of other machines (a PLANER?!) to achieve your
> results.
>
> Granted favors make this business go around.  And if you know
> the right folks, all the better.
>
> So - anyone who wants to get Turcite for their machines,
> they now know who's door to go rapping on!
>
> But if you had been in the business of re-doing that lathe bed,
> it would have been a loss of a job, money wise, given the
> time you put in.  Not that it was not worth it, of course - but
> the conclusion one can draw is that a real, money making shop
> would go broke if they re-conditioned hsm-type lathes for money.
>
> They could not charge the cost of the job.
>
> So I propose an assembly line production for reconditioning them -
> sort of like a cast-iron chain letter.  Send your bed to the
> hsm who can re-grind it.  Then he sends all the beds to the person
> who can do the turcite - and then the assembly goes to the person
> who re-fits the carriage.  One person will be in charge of scaping
> in the tailstocks (if not turcited).
>
> Final stop is at somebody's paint shop.
>
> At the end, everyone gets a brand new lathe, and the stock of
> clapped out machines is rejuvinated.
>
> Only problem is the darn bosses, who will be wondering why the
> *real* work is going so slow!!
>
> Jim


From: Robert Bastow <teenut@home.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Lathe Bed Grinder
Date: Fri, 15 Oct 1999 18:38:41 GMT

You hit the nail right on the head there..

Pure teflon makes slides a slick as..

Problem is that it "Cold Flows" under pressure, so it is difficult to maintain
pre-set clearances for long.

Turcite  (pronounced tur-Kite) is a blend of teflon and other ingredients
designed to prevent this creeping effect.

Wear on surfaces if very low..The turcite is to soft to be abraded much..it
tends to be self healing.  Abrasive particles that would damage the metal slide
surfaces, tend to be totally absorbed by the teflon.  In other words it makes a
poor lapping base.

teenut

wwest2112@my-deja.com wrote:
>
> In article <7u6ehk$i5s$1@usenet01.srv.cis.pitt.edu>,
>   ted+@pitt.edu (William E Williams) wrote:
> > In article <7u4jji$h6e$1@nnrp1.deja.com>, <wwest2112@my-deja.com>
> > wrote:
> > >looked great. I did not scrape then, but took out the fine lines to
> > >smooth with a frosting scrape. Since the hight dropped, I remachined
> > >the saddle ways and epoxed teflon and machined that.
> > >The result was like moving on ice, very slipery.
> > >Keep the ideas comming.
> > >Walt West
> >
> > Walt,
> >       How did the teflon work out?  Has there been much
>
>  wear in it
> I did not have the lathe long enough to evaluate the wear.I used pure
> PTFE (Teflon) because it was available as scrap pieces used as facing
> for elastomeric diaphragm valves. Many types of filled
> (carbon,glass,etc) Teflon are available today that would reduce wear. I
> expect if only the Teflon wore and not the bed it should be fine. I
> recently bought a Teflon rod from Cadilac Plastic and Chemical for
> machining some seals. They have sheet stock available, but in order to
> epoxy it requires a chemical surface etch to get it to bond. The other
> point is the stuff is so creepy I don't think scraping after machining
> is necessary as any high spots would soon creep flat.
> Walt West


From: Robert Bastow <teenut@home.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Lathe Bed Grinder-Moglich
Date: Fri, 15 Oct 1999 18:49:01 GMT

Hi Mike.

I am going to try this type stuff next occassion I need it.  One version is made
by the same people as Turcite.

teenut

Mike Rehmus wrote:

> The nifty stuff is called Moglich (sp?), a pourable epoxy version of
> Turcite.  You wedge the carriage up to height on bits of Turcite and then
> pour this stuff in.  Makes a made-to-order Turcite-lined carriage.  This is
> the way they build some new machine tools (large ones), especially on-site.
>
> John Hofstad-Parkhill <jhparkhill@sihope.com> wrote in message
> news:H%xN3.1775$b84.268297@ptah.visi.com...
> > I was wrong about the turcite. It is expensive, but not nearly as much
> > as I thought I heard. Just checked this evening and it runs about
> > $0.50 / sq.in. Still not cheap, but a little would go a long way.


From: Robert Bastow <"teenut"@ hotmail.com>
Newsgroups: rec.crafts.metalworking
Subject: Re: Re-Conditioning Lathe Beds - SB "Turcite FAQ"
Date: Thu, 24 Feb 2000 05:09:41 GMT

rdanzey@seidata.com wrote:

> One outfit mentioned--Mogoreh--seems to indicate they can do machine
> work on the machine in situ, and presumably use some original un-worn
> surfaces to generate the 'new' true ways/bearing surfaces.  Bob Bastow's
> warning about increased error resulting from this approach seems to fly
> in the face of that, and since I suspect both positions have their
> 'point', I wonder what I'm missing?

Two points you are missing..

Firstly, it is ROBERT Bastow..you don't ever want to meet "Bob"!! ;^)

Secondly..I AM familiar with outfits that will come and regrind ways on
site..They have been around for donkey's years!

HOWEVER!  There is a world of difference between using un-worn sections of the
bed as a REFERENCE, as opposed to using them as a GUIDE.

Most competent travelling regrinders I have ever used, (USED!..Not just heard or
read about!!)  have brought a portable grinder bed with them..accurate slideways
on which the grinder actually travels..and is GUIDED..and which are set up true
and level with REFERENCE to a few original and unworn spots on the bed being
treated.

The same technique could be used by the HSM if he had or had acess to a larger
machine bed than his own worn one.  He could then set up his bed alongside it
and, with patient alignment, I have do doubt that a GOOD job of regrinding could
be achieved.

However..I hold to my original statement..that anyone who imagines they can
regrind the badly worn areas of a bed by GUIDING on the LESS worn areas...I
kidding himself, and any you who believe it!

teenut   AKA ROBERT!!

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