Lathe Boring Bar Holder Plan?

Okay, I give up! 20 or 30 years ago I built a boring bar holder for my Atlas Lathe from plans that I thought had been around for decades. I
want to pass them on to a friend, but I cant' find them!!!! believe me, I TRIED!
This is a cylindrical toolpost that replaces the lantern style tool holder that came with the lathe. The central clamp "Bolt" that squeezes the two halves of the "clamp" around the boring bar is drilled through its side to allow the boring bar to fit right through it. This particular model has three holes in the clamps to accept 1/4", 3/8" and 1/2" boring bars.
I did find a similar plan on the web someplace, but it only has one hole in its side---- for a 1/2" bar, I think.
Yah, I know, why not just scale the needed dimensions and add them to the existing plans. No, that plan is somewhat more complicated and besides, I now obsessed with the need for that VERY plan,
If someone has it, or reference to it, I'd appreciate that info. I just spent about an hour at the drop box and I can't find it there, either.
----The NEAT thing about this style of boring bar holder is that it is probably the stiffest possible way to hold a boring bar that there is.
If my arm is twisted hard enough, I suppose I could draw it up and/or add a couple of pix of it to the drop box.
Pete Stanaitis
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
spaco wrote:

Then you would have, what, ... the PLANS!
Sounds like a plan, Bob
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
spaco wrote:

I've seen a few plans like that, and by happy accident, one was in the book "The Shop Wisdom of D E Johnson", titled "A Classic Boring Bar Holder" that I happened to have out. Given the copyright dates, the original article is in an issue of - ahem - last century's HSM or PM.
The basics: (a) A combined centerpost/T-nut that's drilled through larger than the largest boring bar, in this case 15/16" for a 3/4" bar. The bottom is turned to fit the T-slot, the center is a hair under 1.36" and the top is threaded 5/8"-11. (b) Two cylinders, 2.25" od and a hair over 1.36" id, height equal to the distance from the top of the compound to the lathe axis. There is a spring pin keeping the two cylinders in alignment radially. (c) A top cap, 2.25" od and 3/8" thick, with 1/8" turned down to the same diameter as the centerpost so it fits inside the upper cylinder, drilled to clear the 5/8" stud. (d) Assemble the pieces, align the hole in the centerpost with the lathe axis, put the appropriate drill in the chuck, then drill and ream one of the three pairs of holes, being careful not to drill through the spring pin. Loosen the nut, turn the cylinders but NOT the centerpost by 120 degrees, and do the second hole. And third. (e) Separate the cylinders and face 0.020 off the mating surfaces, so you'll get a better grip on the boring bar when it's clamped. (f) If all your boring bars use the same size bit and the holes in the bars are centered, face the top of the upper cylinder to remove half the thickness of the bit. Normally, the cylinders hold the bar so its center is on the lathe axis, but when you turn the cylinders over, the bar is lower and the top of the bit is on the lathe axis.
Tove
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
See, that's how a newsgroup is supposed to work! Thank you, Tom. I had googled for hours, but the word "classic" is what I was missing!!! It's in HSM M/J, 1983 which is about 2 years before my collection started. But, for some unknown reason, I have 2 original printed copies of the specific article in PiM, (it is undated)!!!! How neat is that????
Pete Stanaitis ---------------------
Tove Momerathsson wrote:

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
spaco wrote:

PM used to send a reprint of that article in subscription offers, I got 3 or 4 because of my HSM subscription. I finally got them to stop sending them by getting a subscription to PiM...
David
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
Tove Momerathsson wrote:

Sounds like an Armstrong boring bar holder. cheers T.Alan
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

    [ ... ]

    I've seen the design in a book of projects for the apprentice, reprinted by whoever it is who reprints out-of-copyright metalworking books. (Old-Timer's disease is keeping me from remembering the name.)
    Enjoy,         DoN.
--
Email: < snipped-for-privacy@d-and-d.com> | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

    That is the name which I was trying to remember.
    I'm now wandering through the list of books trying to find the one in question. I *think* that it is:
        South Bend Lathe Works's         Machine Shop Projects
    http://www.lindsaybks.com/bks4/sblpro/index.html
but I'm not sure. It is a pity that they don't show the cover, which would be more likely to trigger my memory.
    They say:
    "Projects include: lathe mandrel, lathe centers, spur center, 1"     bolt and nut, screw drive, machinist's clamp, clamp lathe dog,     boring bar for lathe, milling arbor for lathe, surface gauge,     small bench vise, adjustable tap wrench, 6" improved water     motor, arbor press, hand power emery grinder, and more."
so the question is whether the "boring bar for lathe" project includes the holder in question.
    Of course, they drop books from their list as they add others, so who knows whether the one which I remember is still there. (Now if I just knew where my copy submerged. :-)
    Enjoy,         DoN.
--
Email: < snipped-for-privacy@d-and-d.com> | Voice (all times): (703) 938-4564
(too) near Washington D.C. | http://www.d-and-d.com/dnichols/DoN.html
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
On 16 Dec 2008 01:37:13 GMT, "DoN. Nichols"

=============The boring bar on page 40 is the between centers type for line boring with the part bolted to the cross slide.
If you are looking for what most people think of as a boring bar and holder see Milne's "Machine Shop Methods" p 212-213 for the holder and p 211-212 for the bar. Book available from Lindseys ISBN 1-55918-223-7 their sku No. 22237 ... $18.95 http://lindsaybks.com/bks/milne/index.html
Unka' George [George McDuffee] ------------------------------------------- He that will not apply new remedies, must expect new evils: for Time is the greatest innovator: and if Time, of course, alter things to the worse, and wisdom and counsel shall not alter them to the better, what shall be the end?
Francis Bacon (1561-1626), English philosopher, essayist, statesman. Essays, "Of Innovations" (1597-1625).
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.