Re: Fw: 1948 9A Quick Change Gearbox analysis


john kling
 

Sorry I meant strange to mean the various combinations of dps in the change gears  and other gears external to a quick change gear box. I understand that the heavy 10 uses 16dp change gears. Does it also use 16dp on the reverse gears etc?


On Tuesday, April 25, 2017 7:32 AM, "Douglas Randall dar1095@... [SOUTHBENDLATHE]" wrote:


 

--------------------------------------------
On Tue, 4/25/17, 'Chuck Lippmeier' chuck@... [SOUTHBENDLATHE] wrote:

Subject: RE: [SOUTHBENDLATHE] Fw: 1948 9A Quick Change Gearbox analysis
To: SOUTHBENDLATHE@...
Date: Tuesday, April 25, 2017, 6:26 AM


 









This is interesting.
Somewhere I read that gun makers sometimes need 7.5 pitch
threading capability and that it was very difficult to find
tooling to do it. I see from your charts that one of the
gearboxes does 7.5 TPI. When I go out to my shop today
I’ll have to look to see what gearbox I have on my SB9A.
If it isn’t the one that does 7.5 TPI and I ever do get a
need for that pitch and if I were to find a gearbox with the
7.5TPI are they interchangeable?Thank
you,Chuck
Lippmeier
 From: SOUTHBENDLATHE@...
[mailto:SOUTHBENDLATHE@...]
Sent: Monday, April 24, 2017 9:25 PM
To: SOUTHBENDLATHE@...
Subject: Re: [SOUTHBENDLATHE] Fw: 1948
9A Quick Change Gearbox analysis    On 04/24/2017 09:35 AM, john
kling jkling222@...
[SOUTHBENDLATHE] wrote:Is the strange
combinations of DPs only a feature of the work shop lathes?
I wonder if the heavy (standard) lathes have a pure 16DP set
up.
 Change
gear lathes do any pitch.There four or five Southbend
quick change gear boxes that I know of. All the inch boxes
have 16tpi. Most lathe builders got away with a lot fewer
pitches. So to answer your question - all the Southbend
lathes with quick change gear boxes do pitches that may seem
odd or in between. Also, nobody normal is going to need to
cut 224 TPI threads - those finer feeds are for
finishing.2 TPI minimum single tumbler
box. I seriously suspect that this is the same gear box as
the 4tpi minimum single tumbler box but with a different
stud gear and chart. Early and uncommon. All settings give
half the TPI as the more common 4 TPI minimum single tumbler
gear box.SLIDING
GEARTOP
LEVERTHREADS PER INCH
FEEDS IN THOUSANDTHSINLEFT2
0.17062.25
0.15172.5
0.13652.75
0.12412.875
0.1187 3
0.1138 3.25
0.1053.5
0.0975CENTER4
0.08534.5
0.07585
0.06835.5
0.06215.75
0.0594 6
0.0569 6.5
0.05257
0.0488RIGHT8
0.04279
0.037910
0.034111
0.03111.5
0.0297 12
0.0284 13
0.026314
0.0244OUTLEFT16
0.021318
0.01920
0.017122
0.015523
0.0148 24
0.0142 26
0.013128
0.0122CENTER32
0.010736
0.009540
0.008544
0.007846
0.0074 48
0.0071 52
0.006656
0.0061RIGHT64
0.005372
0.004780
0.004388
0.003992
0.0037 96
0.0036 104
0.0033112
0.0034 TPI minimum single tumbler
box. The common single tumbler gear box.SLIDING
GEARTOP
LEVERTHREADS PER INCH
FEEDS IN THOUSANDTHSINLEFT4
0.08534.5
0.07585
0.06835.5
0.06215.75
0.0594 6
0.0569 6.5
0.05257
0.0488CENTER8
0.04279
0.037910
0.034111
0.03111.5
0.0297 12
0.0284 13
0.026314
0.0244RIGHT16
0.021318
0.01920
0.017122
0.015523
0.0148 24
0.0142 26
0.013128
0.0122OUTLEFT32
0.010736
0.009540
0.008544
0.007846
0.0074 48
0.0071 52
0.006656
0.0061CENTER64
0.005372
0.004780
0.004388
0.003992
0.0037 96
0.0036 104
0.0033112
0.003RIGHT128
0.0027144
0.0024160
0.0021176
0.0019184
0.0019 192
0.0018 208
0.0016224
0.0015Double tumbler box. Does all
the same pitches as the 4 TPI minimum single tumbler box,
but getting the top row requires changing the stud
gear.STUDLEFT
HAND
TUMBLERTHREADS PER INCH
FEEDS IN THOUSANDTHS40A4
0.04274.5
0.03795
0.03415.5
0.0315.75
0.02976
0.02846.5
0.02637
0.024420A8
0.04279
0.037910
0.034111
0.03111.5
0.029712
0.028413
0.026314
0.024420B16
0.021318
0.01920
0.017122
0.015523
0.014824
0.014226
0.013128
0.012220C32
0.010736
0.009540
0.008544
0.007846
0.007448
0.007152
0.006656
0.006120D64
0.005372
0.004780
0.004388
0.003992
0.003796
0.0036104
0.0033112
0.00320E128
0.0027144
0.0024160
0.0021176
0.0019184
0.0019192
0.0018208
0.0016224
0.0015  Extended range. More rows and
columns - does all of the pitches 4 TPI and finer that the
other inch boxes do without stud gear changes, and adds in
between pitches:STUDLEFT
HAND
TUMBLERTHREADS PER INCH
FEEDS IN THOUSANDTHS40A4
0.08534.5
0.07585
0.06835.5
0.06215.75
0.05946
0.05696.5
0.05256.75
0.05067
0.04887.5
0.045540B8
0.04279
0.037910
0.034111
0.03111.5
0.029712
0.028413
0.026313.5
0.025314
0.024415
0.022840C16
0.021318
0.01920
0.017122
0.015523
0.014824
0.014226
0.013127
0.012628
0.012230
0.011440D32
0.010736
0.009540
0.008544
0.007846
0.007448
0.007152
0.006654
0.006356
0.006160
0.005740E64
0.005372
0.004780
0.004388
0.003992
0.003796
0.0036104
0.0033108
0.0032112
0.003120
0.002840F128
0.0027144
0.0024160
0.0021176
0.0019184
0.0019192
0.0018208
0.0016216
0.0016224
0.0015240
0.001440G256
0.0013288
0.0012320
0.0011352
0.001368
0.0009384
0.0009416
0.0008432
0.0008448
0.0008480
0.0007  The metric gear box.
Obviously a different animal. I don't have a table handy
for this one. I need to find a good clean picture so I can
make one.
 









#yiv7814367201 #yiv7814367201 --
#yiv7814367201ygrp-mkp {
border:1px solid #d8d8d8;font-family:Arial;margin:10px
0;padding:0 10px;}

#yiv7814367201 #yiv7814367201ygrp-mkp hr {
border:1px solid #d8d8d8;}

#yiv7814367201 #yiv7814367201ygrp-mkp #yiv7814367201hd {
color:#628c2a;font-size:85%;font-weight:700;line-height:122%;margin:10px
0;}

#yiv7814367201 #yiv7814367201ygrp-mkp #yiv7814367201ads {
margin-bottom:10px;}

#yiv7814367201 #yiv7814367201ygrp-mkp .yiv7814367201ad {
padding:0 0;}

#yiv7814367201 #yiv7814367201ygrp-mkp .yiv7814367201ad p {
margin:0;}

#yiv7814367201 #yiv7814367201ygrp-mkp .yiv7814367201ad a {
color:#0000ff;text-decoration:none;}
#yiv7814367201 #yiv7814367201ygrp-sponsor
#yiv7814367201ygrp-lc {
font-family:Arial;}

#yiv7814367201 #yiv7814367201ygrp-sponsor
#yiv7814367201ygrp-lc #yiv7814367201hd {
margin:10px
0px;font-weight:700;font-size:78%;line-height:122%;}

#yiv7814367201 #yiv7814367201ygrp-sponsor
#yiv7814367201ygrp-lc .yiv7814367201ad {
margin-bottom:10px;padding:0 0;}

#yiv7814367201 #yiv7814367201actions {
font-family:Verdana;font-size:11px;padding:10px 0;}

#yiv7814367201 #yiv7814367201activity {
background-color:#e0ecee;float:left;font-family:Verdana;font-size:10px;padding:10px;}

#yiv7814367201 #yiv7814367201activity span {
font-weight:700;}

#yiv7814367201 #yiv7814367201activity span:first-child {
text-transform:uppercase;}

#yiv7814367201 #yiv7814367201activity span a {
color:#5085b6;text-decoration:none;}

#yiv7814367201 #yiv7814367201activity span span {
color:#ff7900;}

#yiv7814367201 #yiv7814367201activity span
.yiv7814367201underline {
text-decoration:underline;}

#yiv7814367201 .yiv7814367201attach {
clear:both;display:table;font-family:Arial;font-size:12px;padding:10px
0;width:400px;}

#yiv7814367201 .yiv7814367201attach div a {
text-decoration:none;}

#yiv7814367201 .yiv7814367201attach img {
border:none;padding-right:5px;}

#yiv7814367201 .yiv7814367201attach label {
display:block;margin-bottom:5px;}

#yiv7814367201 .yiv7814367201attach label a {
text-decoration:none;}

#yiv7814367201 blockquote {
margin:0 0 0 4px;}

#yiv7814367201 .yiv7814367201bold {
font-family:Arial;font-size:13px;font-weight:700;}

#yiv7814367201 .yiv7814367201bold a {
text-decoration:none;}

#yiv7814367201 dd.yiv7814367201last p a {
font-family:Verdana;font-weight:700;}

#yiv7814367201 dd.yiv7814367201last p span {
margin-right:10px;font-family:Verdana;font-weight:700;}

#yiv7814367201 dd.yiv7814367201last p
span.yiv7814367201yshortcuts {
margin-right:0;}

#yiv7814367201 div.yiv7814367201attach-table div div a {
text-decoration:none;}

#yiv7814367201 div.yiv7814367201attach-table {
width:400px;}

#yiv7814367201 div.yiv7814367201file-title a, #yiv7814367201
div.yiv7814367201file-title a:active, #yiv7814367201
div.yiv7814367201file-title a:hover, #yiv7814367201
div.yiv7814367201file-title a:visited {
text-decoration:none;}

#yiv7814367201 div.yiv7814367201photo-title a,
#yiv7814367201 div.yiv7814367201photo-title a:active,
#yiv7814367201 div.yiv7814367201photo-title a:hover,
#yiv7814367201 div.yiv7814367201photo-title a:visited {
text-decoration:none;}

#yiv7814367201 div#yiv7814367201ygrp-mlmsg
#yiv7814367201ygrp-msg p a span.yiv7814367201yshortcuts {
font-family:Verdana;font-size:10px;font-weight:normal;}

#yiv7814367201 .yiv7814367201green {
color:#628c2a;}

#yiv7814367201 .yiv7814367201MsoNormal {
margin:0 0 0 0;}

#yiv7814367201 o {
font-size:0;}

#yiv7814367201 #yiv7814367201photos div {
float:left;width:72px;}

#yiv7814367201 #yiv7814367201photos div div {
border:1px solid
#666666;height:62px;overflow:hidden;width:62px;}

#yiv7814367201 #yiv7814367201photos div label {
color:#666666;font-size:10px;overflow:hidden;text-align:center;white-space:nowrap;width:64px;}

#yiv7814367201 #yiv7814367201reco-category {
font-size:77%;}

#yiv7814367201 #yiv7814367201reco-desc {
font-size:77%;}

#yiv7814367201 .yiv7814367201replbq {
margin:4px;}

#yiv7814367201 #yiv7814367201ygrp-actbar div a:first-child {
margin-right:2px;padding-right:5px;}

#yiv7814367201 #yiv7814367201ygrp-mlmsg {
font-size:13px;font-family:Arial, helvetica, clean,
sans-serif;}

#yiv7814367201 #yiv7814367201ygrp-mlmsg table {
font-size:inherit;font:100%;}

#yiv7814367201 #yiv7814367201ygrp-mlmsg select,
#yiv7814367201 input, #yiv7814367201 textarea {
font:99% Arial, Helvetica, clean, sans-serif;}

#yiv7814367201 #yiv7814367201ygrp-mlmsg pre, #yiv7814367201
code {
font:115% monospace;}

#yiv7814367201 #yiv7814367201ygrp-mlmsg * {
line-height:1.22em;}

#yiv7814367201 #yiv7814367201ygrp-mlmsg #yiv7814367201logo {
padding-bottom:10px;}


#yiv7814367201 #yiv7814367201ygrp-msg p a {
font-family:Verdana;}

#yiv7814367201 #yiv7814367201ygrp-msg
p#yiv7814367201attach-count span {
color:#1E66AE;font-weight:700;}

#yiv7814367201 #yiv7814367201ygrp-reco
#yiv7814367201reco-head {
color:#ff7900;font-weight:700;}

#yiv7814367201 #yiv7814367201ygrp-reco {
margin-bottom:20px;padding:0px;}

#yiv7814367201 #yiv7814367201ygrp-sponsor #yiv7814367201ov
li a {
font-size:130%;text-decoration:none;}

#yiv7814367201 #yiv7814367201ygrp-sponsor #yiv7814367201ov
li {
font-size:77%;list-style-type:square;padding:6px 0;}

#yiv7814367201 #yiv7814367201ygrp-sponsor #yiv7814367201ov
ul {
margin:0;padding:0 0 0 8px;}

#yiv7814367201 #yiv7814367201ygrp-text {
font-family:Georgia;}

#yiv7814367201 #yiv7814367201ygrp-text p {
margin:0 0 1em 0;}

#yiv7814367201 #yiv7814367201ygrp-text tt {
font-size:120%;}

#yiv7814367201 #yiv7814367201ygrp-vital ul li:last-child {
border-right:none !important;
}
#yiv7814367201



Join SouthBendLathe@groups.io to automatically receive all group messages.