Tapers and Chuck keys page

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  1. Tapers and Chuck keys page
    1. Disclaimer
  2. Milling Machine Tapers
    1. Spindle Size Number

  3. Universal Kwik-Switch
    1. Kwik-Switch 200 part numbers
      1. Universal 5 digit numbers
      2. Universal 6 digit numbers
      3. SPI numbers
      4. Scully-Jones numbers
  4. Tool-Holders with Collars or Flanges
    1. Single Flange Tool-Holders
    2. Dual Flange Tool-Holders
    3. BT-Flange and ISO-Flange
    4. Caterpillar V-flanges
    5. DIN 69871-A TAPER
  5. R8, R-8 or M1TR taper -- Common Bridgeport Tapered Draw-Bar
  6. Machine Taper Dimensions table - Morse - Brown & Sharp - Jarno - Jacobs
  7. Chuck keys
  8. B-Taper (DIN ISO 239)



Milling Machine Tapers

Parent page is Machining

There are really only a few tapers in common use even with all the names for milling machine tapers. Quite a few manual milling machines use the "R-8" taper, but most CNC and large machines use something else. A tool-holder consists of 2 sections separated by the gage line (the gage line is an imaginary line marking the portion of the tool-holder that matches the bottom edge of the machine spindle). The taper fits into the spindle allowing the machine spindle to transfer rotary motion to the tool holder which holds the tool.

A toolholder has a 2 part specification, taper and tool. This page covers the machine-to-toolholder standard and not the holder-to-tool standard. and example might help. A NMTB #30 collet chuck and an NMTB 1/2" endmill holder fit the same machine, but hold different tools.

The NMTB refers to the taper standard family - the #30 the shank size (if they leave off the #30 part it is assumed to be the small one.) At the end of the tool-holder name is the name of the tool type - 1/2" end-mill holder

NMTB(National Tool Builders Association)

MMT stands for Milling Machine Taper - what became Erickson quick-change spindles

Conversely, a NMTB 1/2" end-mill tool-holder and a Universal Kwik-Switch 200 1/2" end-mill tool-holder will hold the same tool, but fit different machines. The drawings below show only the taper portion of the tool-holder.

Spindle Size Number

The ANSI standard size is determined by the machine size; Larger machines use larger shanks.

Spindle size to Machine size
Taper Shank No. Machine Size
#60 Very large machines
#50 Medium size machines (20 to 50 HPs)
#40 Small size machines
#30 Very small machines

All of the major tapers, except the Universal Kwik-Switch family, use the 3 1/2" in 12" model of the NMTB or 7:24. A 3/8" end-mill #50 NMTB tool-holder is about a serious 9 pounds of metal compared to dainty 3/4 of a pound for a #30 NMTB 1/4" end-mill tool-holder.


Universal Kwik-Switch

A Tool-Holders with Ears!

This taper style is also made by Collis who call it Rapid-Switch.

The Kwik-Switch is supplied as alternative tooling in Bridgeport, Wells index, and other machines. The 200 series is pretty much equivalent to the NMTB #30, but has more mass and a more positive lock.


This is not a Milling Machine taper.it is actually a 2 inch TPF.
2"/ft is about 9.46 deg   But the taper on the 200 is really 9.142848 deg ..

the 7/24 tapers are 16.26 deg .. (The narrower Kwik-Switch taper doesn't need as much vertical holding force - thus a nut rather than a drawbar.. )



, Kwik-switch.jpg
Kwik-Switch Size A B C E F H J K L M
100 .875 1.44 0.16 0.312 0.250 1.12 1.56 0.375 1.06 0.68
200 1.312 2.50 0.22 0.375 0.312 1.75 2.12 0.500 1.68 0.97
300 1.625 2.94 0.28 0.438 0.375 2.00 2.50 0.500 1.94 1.22
400 2.250 3.62 0.34 0.500 0.438 2.81 3.25 0.625 2.75 1.75

According to Wells Index:

200 KS stands for 200 Kwik Switch (AKA Rapid-Switch or rapid change) designed by Universal Engineering and it is not like any other. It is about the same size as #30 NMTB or #30 MMT. Used and new tooling is available.

As the holder lock-nut is opened, coil springs are compressed. When the open position is reached, a mechanical latch holds the nut open. This latch is operated by a trigger pin. The trigger pin is depressed by one of the tool adapters lugs as the adapter is inserted into the spindle socket. When the trigger pin is depressed, it releases the compression springs. This causes the spindle nut to rotate which draws the tool adapter up into the locking angle tapered socket. Since locking force is always present, the nut continues to tighten under load.


Other companies make tooling that will fit it and call it rapid switch or rapid change. It is about the same size as #30 NMTB or #30 MMT. Used and new tooling is available
http://universaldevlieg.com/
https://toolholderexchange.com/kwik-switch/




2008 Catalog

Kwik-Switch 200 part numbers

Universal 5 digit numbers * means have..

*15905 Acura-Tap T&C Collet Chuck 1/2"

15925 Quick Change Tension & Compression Tap Chucks  - tap adapter size -1
             #0-9/16 Hand  1/8 Pipe



More tap adapters - see catalog above
60047 Jacobs Taper #33 Adapter (same as 80255)
80220 1/2" DT collet Chuck
80226 Morse #1
*80227 Morse #2
80228 Morse #3 has open end drift
80231 Shell mill adapter 0.500"
80232 Shell mill adapter 0.750"
80233 Shell mill adapter 1.000"
80236 Acura-Flex Collet Chuck
*80242 End Mill Holder 0.375" and as Briney
**80243 End Mill Holder 0.500" and as Briney (total 3)
80244 End Mill Holder 0.625" as Briney
*80245 End Mill Holder 0.750" and as Briney
80246 End Mill Holder 0.875"
*80247 End Mill Holder 1.000"

Jacobs Adapters - more lower
80251 Jacobs #0
80252 Jacobs #1 As Scully-Jones 95512-J1
80253 Jacobs # 2
80254 Jacobs #6
*80255 Jacobs #33
80261 Stubarbor 3/4" 0.75
80262 Stub arbor 7/8" 0.875
*80263 1" Stub Arbor With 4 spacers (two 1/4", one 3/8", and one 1/8"), removable Woodruff key and nut
80274 Boring Head (for 3/8" sq tool)
80275 Boring Head (for 3/8" sq tool)  6.5" long
*80292 Acme Shank Adapter 3/4"

80698 Jacobs #3
80721 End-mill holder .250"
80757 BORING HEAD ADAPTER 1-1/4"-20?? 1 1/4 fine thread 1/2 long and 3 3/8 OAL over all length
80851 1.5" mill holder
80881 Boring Head Adapter 7/8-20
80891 Boring Head Adapter 1.5-18,
90258 Jacobs # 2 ???
* 97041 = 97101 + 97047
*97047 OY boring Chuck head - Y Double taper
*97101 Shank (could be about the same as 80891??  Is this a normal boring head adapter? )
97374 = 97375 + 97101
97375 3 hole (3/8") boring Chuck.

Universal 6 digit numbers

801163 Jacobs #4
801431 End Mill Holder 0.1875"
801512 Boring Head Adapter 7/8-18
802481 End Mill Holder 0.3125"
802785 End Mill Holder 0.125"
*805560 Boring tool Valenite EZ-set AHACS (1.25"??)
* 805564 Boring tool size 5 MicroBore, 5" projection  Has 317896? microbore cartridge (5-40x0.375" FH cartrige scresw"   #3-48x.250" insert screw)
Insert - TC_ _1102_ _ ???? Valenite EZ-set BHACS

809562 arbor 7/8" recess with 1/2-20 bolt

ER collet chucks
*KS2ER16112  ER16 - max tightening torque 68 Nm
*KS2ER32181 ER16 - max tightening torque 170 Nm
 
 

Dimensions of Kwik-Switch 200 mill holders
Number A(diameter) B C M
802785 0.125 0.44 1.03 0.62
801431 0.1875 0.56 1.03 0.68
80721 0.25 0.75 1.41 1
802481 0.3125 0.75 1.41 1
80242 0.375 0.75 1.41 1
802482 0.4375 ? ? ?
80243 0.5 0.88 1.41 1.31
80244 0.625 0.94 1.41 1.62
80245 0.75 1 1.66 1.72
80246 .8750 (1) 1 1.91 1.94
80247 1.0000 (1) 1.12 2.03 1.94

Briney Numbers

*QS200E-038-141 3/8" end mill holder
*QS200E-050-141 1/2" end mill holder
*QS200E-062-141 5/8" end mill holder
*QS200E-075-166  3/4" end mill holder
*QS200-THM-100 Tap Holder ?  Not as heavy as the end-mill holder

SPI numbers

*74-086 B16
 

Scully-Jones numbers

*95512-J1  - Jacobs #1

Tool-Holders with Collars or Flanges

Single Flange Tool-Holders

The single collar taper is the most popular, as evidenced by the numerous names it has. Most often NMTB or Erickson Quick Change. NMTB (from National Machine Tool Builders' Association, 1927. and also known as DIN 2080 / IS 2340 SHANK)

You'll see it called Quick Change, NMTB, MM, National Standard, American Standard Machine Taper, ISOXX, & QCXX...

The American Standard Steep Machine Taper (ASA B5.10-1963) defines 12 tapers: #5, #10, #15, #20, #25, #30, #35, #40, #45, #50, #55, #60. Those numbers in bold are the "Preferred Series" while the others are in the "Intermediate Series".

ANSI mentions six taper shank sizes including #30, #35, #40, #45, #50, and #60. For all the sizes the taper is 3 1/2" per foot. The taper is 3.500 inches per foot and is also referred to as "7 in 24" or 7/24 or better yet 7:34; the computed angle is 16.5943 degrees


, NMTB.jpg
Shank Slot A B C
30 16.1 [.634] 31.75 [1.250] 68.4 [2.75] 1/2-13
40 16.1 [.634] 44.45 [1.750] 93.4 [3.75] 5/8-11
50 25.7 [1.012] 69.85 [2.750] 126.8 [5.12] 1-8

Dual Flange Tool-Holders

There are two common dual flange types: V-flange (often referred to as Caterpillar V-flanges) and BT-flange.

BT-Flange and ISO-Flange

BT-flange holders are widely used in Japanese and European made machining centers and have metric threads for the retention knob, but their adapters can be designed to accommodate a wide range of inch-dimensioned cutting tools.

The BT Flange is also known as

  • JMTBA MAS-403 "BT"
  • JIS B 6339 - 1986
  • JIS B6339 - 1992
  • ISO 7388/1 - 1983


, BT-flange.jpg

MODEL D1 D2 t1 t2 L1 L2 L3 L d1 d2 G
BT20* ? ? ? ? ? ? ? ? ? ? ?
BT30 46 38 20 2 48.4 34 24 70.4 31.75 12.5 M12
BT40 63 53 25 2 65.4 70 30 92.4 44.45 17 M16
BT50 100 85 35 3 101.8 90 45 139.8 69.85 25 M24
*used by SAKAI MM-250 S3 Milling machine

Caterpillar V-flanges

Caterpillar V-flanges use inch threads for the retention knob and are used to hold inch-dimensioned cutting tools.

You'll see the CAT flange referred to as DIN69871

I've seen them most often referred to as CAT-30, CAT-40, CAT-45, and CAT-50 and CAT-40 seems to be the most common.

, V flange.jpg
SHANK
SIZE
A
GAGE LINE
B C D
V30 1.250 1.812 1.875 1/2-13
V40 1.750 2.500 2.687 5/8-11
V45 2.250 3.250 3.250 3/4-10
V50 2.750 3.875 4.000 1-8

[Inches]

DIN 69871-A TAPER

Need information on this one... , DIN69871-A.gif
MODEL D1 D2 t1 t2 L1 L2 L3 d1 d2 M max G
10 23 18.46 5.5 ? 20.5 ? ? 15.875 ? ? ?
20 33 27 8 ? 33.3 ? ? 22.225 ? ? ?
25 37 31 8 ? 39.7 ? ? 25.4 ? ? ?
30 50 44.30 15.9 3.2 47.8 33.5 24 31.75 13 45 M12
40 63.55 56.25 15.9 3.2 68.4 42.5 32 44.45 17 50 M16
50 97.5 91.25 15.9 3.2 101.75 61.5 47 69.85 25 80 M24

R8, R-8 or M1TR taper -- Common Bridgeport Tapered Draw-Bar

This is not truly a taper as defined by Machinery's Handbook, since it is held in place by a drawbar. Picture a long 7/16"NF bolt leading down through the spindle, threading onto the R-8 tool-holder. The included angle is 8.25°1 OD of 1.25" 18.85/2 degrees or 8.25??

Taper = 16 Deg 51 Min.Included

End Dia. .9495 +0 -.0003

Overall from front dia. of 1 1/4"is 4" Undercut dia. 15/16"

The "arctan(3.5/12)" solution by definition implies a right triangle with a 3.5" short side and 12" long side. Thus, the hypotenuse is 1.25".

, R-8.gif

Machine Taper Dimensions table - Morse - Brown & Sharp - Jarno - Jacobs

Taper Name Large End
Diameter
Taper/ft Taper/in Angle in degrees
From Center
Small End
Diameter
Length
#0 Morse 0.356 0.625 0.052 1.491 0.252 2.000
#1 Morse 0.475 0.599 0.050 1.429 0.369 2.130
#2 Morse 0.700 0.599 0.050 1.431 0.572 2.560
#3 Morse 0.938 0.602 0.050 1.438 0.778 3.190
#4 Morse 1.231 0.623 0.052 1.488 1.020 4.060
#4-1/2 Morse 1.500 0.624 0.052 1.489 1.266 4.500
#5 Morse 1.748 0.632 0.053 1.507 1.475 5.190
#6 Morse 2.494 0.626 0.052 1.493 2.116 7.250
#7 Morse 3.270 0.624 0.052 1.489 2.750 10.000
#1 Brown & Sharpe 0.239 0.502 0.042 1.198 0.200 0.940
#2 Brown & Sharpe 0.300 0.502 0.042 1.198 0.250 1.190
#3 Brown & Sharpe 0.375 0.502 0.042 1.198 0.313 1.500
#4 Brown & Sharpe 0.421 0.502 0.042 1.199 0.350 1.690
#5 Brown & Sharpe 0.539 0.502 0.042 1.197 0.450 2.130
#6 Brown & Sharpe 0.600 0.503 0.042 1.201 0.500 2.380
#7 Brown & Sharpe 0.720 0.502 0.042 1.197 0.600 2.880
#8 Brown & Sharpe 0.899 0.501 0.042 1.196 0.750 3.560
#9 Brown & Sharpe 1.078 0.501 0.042 1.196 0.900 4.250
#10 Brown & Sharpe 1.260 0.516 0.043 1.232 1.045 5.000
#11 Brown & Sharpe 1.498 0.501 0.042 1.196 1.250 5.940
#12 Brown & Sharpe 1.797 0.500 0.042 1.193 1.500 7.130
#13 Brown & Sharpe 2.073 0.500 0.042 1.194 1.750 7.750
#14 Brown & Sharpe 2.344 0.500 0.042 1.194 2.000 8.250
#15 Brown & Sharpe 2.615 0.500 0.042 1.194 2.250 8.750
#16 Brown & Sharpe 2.885 0.500 0.042 1.194 2.500 9.250
#17 Brown & Sharpe 3.156 0.500 0.042 1.194 2.750 9.750
#18 Brown & Sharpe 3.427 0.500 0.042 1.194 3.000 10.250
#2 Jarno 0.250 0.600 0.050 1.432 0.200 1.000
#3 Jarno 0.375 0.600 0.050 1.432 0.300 1.500
#4 Jarno 0.500 0.600 0.050 1.432 0.400 2.000
#5 Jarno 0.625 0.600 0.050 1.432 0.500 2.500
#6 Jarno 0.750 0.600 0.050 1.432 0.600 3.000
#7 Jarno 0.875 0.600 0.050 1.432 0.700 3.500
#8 Jarno 1.000 0.600 0.050 1.432 0.800 4.000
#9 Jarno 1.125 0.600 0.050 1.432 0.900 4.500
#10 Jarno 1.250 0.600 0.050 1.432 1.000 5.000
#11 Jarno 1.375 0.600 0.050 1.432 1.100 5.500
#12 Jarno 1.500 0.600 0.050 1.432 1.200 6.000
#13 Jarno 1.625 0.600 0.050 1.432 1.300 6.500
#14 Jarno 1.750 0.600 0.050 1.432 1.400 7.000
#15 Jarno 1.875 0.600 0.050 1.432 1.500 7.500
#16 Jarno 2.000 0.600 0.050 1.432 1.600 8.000
#17 Jarno 2.125 0.600 0.050 1.432 1.700 8.500
#18 Jarno 2.250 0.600 0.050 1.432 1.800 9.000
#19 Jarno 2.375 0.600 0.050 1.432 1.900 9.500
#20 Jarno 2.500 0.600 0.050 1.432 2.000 10.000
#0 Jacobs 0.250 0.592 0.049 1.412 0.228 0.440
#1 Jacobs 0.384 0.925 0.077 2.207 0.333 0.660
#2 Jacobs 0.559 0.979 0.082 2.335 0.488 0.880
#2 Short Jacobs 0.549 0.979 0.082 2.335 0.488 0.750
#3 Jacobs 0.811 0.639 0.053 1.525 0.746 1.220
#4 Jacobs 1.124 0.629 0.052 1.501 1.037 1.660
#5 Jacobs 1.413 0.620 0.052 1.480 1.316 1.880
#6 Jacobs 0.676 0.623 0.052 1.487 0.624 1.000
#33 Jacobs 0.624 0.762 0.064 1.818 0.561 1.000

Parent page is Machining

Chuck keys

Need information about origin of standard and metric standards..

Key Size Comments - Chucks
K0 1/8" 0.125"
K2 1/4" 0.250"
K3 (K3C?) 5/16" 0.312 5"
K4 3/8 0.375" (#9)
K5 7/16 0.437 5" (#26)
K7 7/32" 0.218 75"
?? 21/64 0.328 125
K30 15/64" 0.234 375
K32 1/4" 0.250"
KG 1/4" 0.250"
KI 5/32" 0.156 25"
KK 9/32" 0.281 25"
K30 15/64" 0.234 375" (#13)

B-Taper (DIN ISO 239)

Often used for drill chucks, like the older Jacobs tapers

b-taper
Size Large
End
Small
End Dia.
Taper
Length
Taper
per ft.**
B6 6,350mm
0.2500"
5,85mm
0.2303"
10mm
0.3937"
0.6
B10 10.094mm
0.3974"
9,4mm
0.3701"
14,5mm
0.5709"
0.5743
B12 12,065mm
0.4750"
11,1mm
0.4370"
18,5mm
0.7283"
0.6259
B16 15,733mm
0.6194"
14,5mm
0.5709"
24mm
0.9449"
0.6165
B18 17,780mm
0.7000"
16,2mm
0.6378"
32mm
1.2598"
0.5925
B18* 17,431mm
0.6863"
16,2mm
0.6378"
25mm
0.9843"
0.5909
B22 21,793mm
0.8580"
19,8mm
0.7795"
40,5mm
1.5946"
0.5905
B24 23,825mm
0.9380"
21,3mm
0.8386"
50,5mm
1.9882"
0.6

* 7mm short of DIN ISO 239
** 12((D-d)/L)

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