Subject: Help ME Please!!!

From: [email-masked](Mr500CM)
Date: 14 Sep 1996 05:43:38 GMT

I'm new to metalworking and I'm working with aluminum.I am making
photographic brackets and other items and need to learn about tapping new
threads. My first question is this: I need to have a 1/4-20 thread, how big
of a hole should I drill to tap this size. Actually there are other sizes
too but 1/4-20 is my main size. Is there a chart or a refernce book. 
 
Second I need a source for a good assortment of nuts & bolts and screws. I
used to see these great assortments real cheap and now that I need it I
can't find it. Any I deas where I can find them? 
 
Last question: I'm using aluminum bar stock, 1inch x 1/4 inch and I'm
currently paying $2.65 per foot. I'm not sure if this is a fair price, if
not I could use a good source in the New York City/Long Island area. 
 
Thanks so much. 
 
Lance

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From: [email-masked] (Alan Shinn)
Date: Sat, 14 Sep 1996 11:14:54 -0800

> not I could use a good source in the New York City/Long Island area. 

Lance:
Dave Keith sent the following chart in awhile ago, here it is again:

Dec.    Inch   Wire  Tap            Dec.    Inch   Wire  Tap
Inches  (mm)   Let.  Thread         Inches  (mm)   Let.  Thread

0.0156   1/64                       0.3230           P
0.0312   1/32                       0.3281   21/64
0.0469   3/64        #0-80          0.3320           Q   3/8-24
0.0625   1/16        #1-64          0.3390           R   1/8-27 Pipe
0.0635          52   #1-72          0.3438   11/32

0.6700          51   #2-56          0.3480           S
0.0700          50   #2-64          0.3580           T
0.0781   5/64        #3-48          0.3594   23/64
0.0810          46   #3-56          0.3680           U   7/16-14
0.0890          43   #4-40          0.3750   3/8

0.0935          42   #4-48          0.3770           V
0.0938   3/32                       0.3860           W   7/16-20
0.0995          39   #5-40          0.3906   25/64
0.1040          37   #5-44          0.3970           X
0.1065          36   #6-32          0.4040           Y

0.1094   7/64                       0.4063   13/32
0.1130          33   #6-40          0.4130           Z
0.1250   1/8         5/32-32        0.4219   27/64       1/2-13
0.1285          30   5/32-36        0.4375   7/16        1/4-18 Pipe
0.1360          29   #8-32          0.4531   29/64       1/2-20

0.1406   9/64                       0.4688   15/32
0.1470          26   3/16-24        0.4844   31/64       9/16-12
0.1495          25   #10-24         0.5000   1/2
0.1563   5/32                       0.5156   33/64       9/16-18
0.1570          22   3/16-32        0.5313   17/32

0.1590          21   #10-32         0.5469   35/64
0.1719   11/64                      0.5512   (14mm)      5/8-11
0.1730          17   #12-24         0.5625   9/16
0.1770          16   7/32-24        0.5781   37/64       5/8-18
0.1800          15   #12-28         0.5906   (15mm)      3/8-18 Pipe

0.1875   3/16                       0.5938   19/32
0.1890          12   7/32-32        0.6094   39/64
0.1990           8   1/4-20         0.6250   5/8         11/16-16
0.2031   13/64                      0.6406   41/64
0.2130           3   1/4-28         0.6563   21/32       3/4-10

0.2188   7/32                       0.6719   43/64
0.2340           A                  0.6875   11/16       3/4-16
0.2344   15/64                      0.7031   45/64
0.2380           B                  0.7188   23/32       1/2-14 Pipe
0.2420           C                  0.7344   47/64

0.2460           D                  0.7500   3/4
0.2500   1/4     E                  0.7656   49/64       7/8-9
0.2570           F   5/16-18        0.7813   25/32
0.2610           G                  0.7969   51/64
0.2656   17/64                      0.8125   13/16       7/8-14

0.2660           H                  0.8281   53/64
0.2720           I   5/16-24        0.8438   27/32
0.2770           J                  0.8594   55/64
0.2810           K                  0.8750   7/8         1-8
0.2813   9/32        5/16-32        0.8906   57/64

0.2900           L                  0.9063   29/32
0.2950           M                  0.9219   59/64       3/4-14 Pipe
0.2969   19/64                      0.9375   15/16       1-14
0.3020           N                  0.9531   61/64
0.3125   3/16        3/8-16         0.9688   31/32

0.3160           O                  0.9844   63/64       1 1/8 -7

-- 
Al Shinn   (Tinker)
alshinn@ sirius.com