I just typed Turcite into Yahoo's search engine and I got back links
to Boedeker plastic's data sheet on Turcite. It is related to Delrin
which is a plastic material I've used before. Very easy to machine,
takes a high polish and is extremely strong and "slippery".


http://www.boedeker.com/turcax_p.htm

Glen Reeser

I now have three SB's
9" A
9" C
10" C This one I haven't seen yet. I get to visit it this weekend.


--- In southbendlathe@y..., Thomas.G.Brandl@c... wrote:

--- In southbendlathe@y..., earl@w... wrote:
Earl,
I looked at the South Bend Page and they use turcite in their

new

products. I was wondering what exactly it is and where its

available

from? How is it attached to the ways, Glue Soildering?
Tom Brandl

Some may recall my earlier post (back in May) regarding an SB13
scraping project. As an update, I would like to say that the

machine

is now up and running and doing very well ......... for a critter

old

enough to be eligible for SS.

It did not, however, reach completion in the fashion I had
earlier anticipated.

To make a long story short; as I was reaching the final stages of

way

scraping and saddle fitting, a pristine SB13 bed appeared on

ebay.

Since the seller was here in the west, I bid on it ......... for

the

grand sum of $51 ....... and was successful. It cost more in

gasoline

to retrieve it than it cost to purchase but it was worth it.

The bed was as advertised and worth every nickel of the cost.

So, the ultimate scraping project may not have ended in total
completion ........ as a scraping project ...... but much was

learned

along the way and a useful tool has been resurrected from, what

was,

mostly useless cast iron.

I just found a nice, more recent vintage, compound slide with the
newer and larger micro dials and a face plate, which will lend

greater

ease of use to the machine.

As matters now stand, this machine has it's birth in 1934

.........

with various appendages replaced along the way. The headstock and
gearing is all original. As is the tail stock, saddle and apron.

The

bed is early 80's with turcite build-up in the saddle. ........

maybe

a bit like Johnny Cash's old tune about the auto worker who set

out

to

scrounge parts for a Cadillac. .......... for those old enough to
remember the tune.

BTW, the "Turcite" buildup is really a slick way to compensate

for

wear in sliding parts. It performs well, cuts "stick-slip" and

has a

lower co-efficient of friction. It is easy to do (relatively),

easy

to

replace, if need be, and done properly, can bring an old machine

back

to original standards.

In this machine, the turcite was installed to compensate for wear

in

both the original ways as well as the saddle itself. Since the

bed

has

now been replaced with one having factory dimension ways, the

saddle

is now riding .020 high. Being fundamentally lazy and unable to

see

any problem with a saddle riding .020 higher than original, it

will

remain at the present level ........... unless something presents

a

reason to conclude otherwise.

I did, however, shim (down) both the apron and the rear gib by an
equivalent amount in order to accomodate the longitudinal gear

rack,

lead screw and the rear gib surface. In the meantime, it has

about

100

years of wear ahead of it, before the saddle returns to original
height and the shims can be removed.

The tail stock baseplate was built up with a wear resistant

epoxy. I

would have used Turcite again but didn't have any in thin

sections.

Surprisingly, it only required .010 on the flat and .005 on the
inverted V. But the inverted V was flared several thousandths, at

the

forward end.

The base plate was shimmed level and to proper height for spindle
center. Narrow brass shims were super glued in place for the

epoxy

phase. A strip of wax paper serve's nicely to prevent adhesion

to

the

ways. Weight the base plate and check for level and square to the
center line axis.

The wear resistance epoxy is very tough and resistant to wear. A

cold

chisel is required to remove it ............ or better, heat to

300

or

400 degrees and scrape it off.

My only long term concern is that it may prove deleterious to the

cast

iron ways. But that's an easy matter to keep an eye on. If

there's

any

sign of scratching or wear, the epoxy will be replaced with

Turcite.

I put a Phase II CXA, wedge type tool post on it. The original 3

PH

motor was replaced with 1 1/4 HP DC motor and speed control. The
leather belt was replaced with a flat belt from a local

distributor.

I

have taken .030 (.060 total) cuts in steel without belt problems.

I'm still in the test and sniff (for problems) phase but so far,

the

accuracy is within my limits of testing and it is performing very
well. ........... but it has been a time consuming project.

Tip: With a DC drive and speed control, there is no reasonable

way

to

determine spindle RPM, without a tach. I solved the problem with

a

length of allthread and a stop watch.

Wrap tape around the nut ......... or otherwise build it up

........

so it fits securely inside the spindle. Time the advance of the

nut

as

it's being driven down the length of allthread by the spindle.

Measure the distance the nut travels and multiply by the pitch of

the

threads. If timed for one minute, that will equal the RPM.

A fine pitch thread, like 1/4 - 20 will work better for higher

RPMs.

And of course, some care should be taken since the rod must be

hand

held.

I did the measurement for each pully step and each 10 unit

advance

on

the speed control. A handy table of spindle speeds, now adorns

the

face of the speed control.