Friday, 22 September 2017

Metrology - the science of measurement


Some notes of interesting techniques, sites and people concerning this topic.

On YouTube there are some very interesting video clips on prototyping and machine metrology which are a must see by Dan Gelbart. He shares a measurement technique, which he refers to as reversal technique. In essence two unknown surfaces can be mapped, and compared if a common reference surface also of unknown dimension is used.
https://makezine.com/2015/03/20/18-lessons-smart-prototyping-self-made-billionaire/


Airy and Bessel Points effects explained.
https://www.mitutoyo.co.jp/eng/pdf/E4329_QuickGuide.pdf

31/03/2018 - Recently I browsed  through Stefan Gotteswinter web site, wealth of knowledge! Here he shared a link to 50 tidbits for precision work, #47 references Donaldson Reversal, still need to read up more on this, but I believe this is what Dan Gelbart refers to.

Thursday, 21 September 2017

Colchester Chipmaster Spindle and Bearings

The site at precision rpm has a list of bearing designations used in Cochester Lathes.

http://www.precisionrpm.com/pub/gamets/lathes_1

The Chipmaster uses these bearings


Spindle Nose Bearing: 113060X/113101XH 



Dimensions (mm)
d D T C E F
60.325 101.6 58 46.88 18.94 5.56




Spindle tail bearing: 111050/111090

111050-111090-gamet-single-row-plain-cup-50x90x26-75mm

Dimensions (mm)
d D T C B F
50 90 26.75 20.4 29 6.35

Static Stiffness Basic Rating Speed Weight Brand
Radial Axial Radial Axial
60 11 1435 830 7400 1.38 Gamet Brand Logo


LATHE

GAMET FRONT BEARING

600 LATHES
FRONT BEARING REFERENCE

GAMET REAR BEARING

600 LATHES
REAR BEARING REFERENCE

Colchester Bantam111050/111090CBA-0070112045/112085CBA-0060
Colchester Chipmaster 6-inch
Colchester Student 1200
113060X/113101XHE+10-111050/111090-
Colchester Master 2500
Colchester Student 1800
130070/130120CB336-1219
BA-0090
113060X/113101XPB336-1218
Colchester Triumph131093X/131152XCB336-1228133075/133130P
( 20 Springs )
B336-1322
Colchester Triumph ( SPECIAL )
APPROX 100 M/C's
160098X/160152XC-133075/133130P
( 20 Springs )
B336-1322
Colchester Mascot 1600181118/181190X C-131097/131152XP
( 8 Springs )
B336-1331
BA-0010
Colchester Mascot 8 1/2-inch181118/181190XHE+20-131095/131152X-
Colchester Mascot / Mastiff164133X/164196XHSE+60
( X1124A )
24 Rollers in A track
12 Rollers in B track
B336-1787105115/105165P
( 8 Springs )
( X1125A )
15 Rollers 
B336-1353
Colchester Mascot - Dalian164133XD/164196XHS
( X1291A )
24 Rollers in A track
12 Rollers in B track
B336-1805105115/105165P
( 8 Springs )
( X1125A )
15 Rollers 
B336-1353
Colchester Mastiff - Dalian163150D/163210HR
( X1292A )
26 Rollers in A track
13 Rollers in B track
B336-1806109127X/109175P
( 8 Springs )
( X1216A )
15 Rollers 
B336-1354
Colchester Mastiff (104 Bore )163150/163210HRE+60
( X1262A )
26 Rollers in A track
13 Rollers in B track
B336-1789109127X/109175P
( 8 Springs )
( X1216A )
15 Rollers 
B336-1354
Colchester Magnum (120 Bore )203156/203235HRE+10
( X950A )
B336-1785203145/203235P
( 8 Springs )
( X951A )
B336-1348
CNC 650164133X/164196XHSE+10-184120/184190P-
Colchester Magnum ( 170 Bore )206210/206290CB336-1349206190X/206290CB336-1351
Harrison M250
Harrison V280
Harrison M280
Harrison VS280
111050/111090 CBA-0070112045/112085CBA-0060
Harrison M300
Harrison VS330
Harrison V330
124070/124112XCBA-0040110055/110100CBA-0050
Harrison M350140085/140140CBA-0080130070/130120CBA-0090
Harrison M400
Harrison M450
Harrison M500
Harrison V450
Harrison V530
141107X/141165XHSRE-10BA-0020140085/140140 PBA-0030
Harrison Alpha 330G124070/124112XCBA-0250G113060/113100PBA-0260
Harrison Alpha 800 (120 BORE)203156/203235HE+40B336-1794203145/203235P
( 12 Springs )
B336-1795 
Harrison Alpha 800 (170 BORE)206210/206290CB336-1349206190X/206290CB336-1351
Colchester Combi K2
Harrison Alpha 400 U
131093X/131155C
( X1268A )
B336-1792131092X/131152XD
( X1269A )
B336-1793
Harrison Alpha 400 T131093X/131152XCB336-1228133075/133130P
( 20 SPRINGS )
B336-1322
Colchester Combi K3
Harrison Alpha 460 U
164130/164202C
( X1270A )
B336-1796164127X/164200XD
( X1271A )
B336-1797
Harrison Alpha 460 T164133X/164196XHSE+60
( X1124A )
24 Rollers in A track
12 Rollers in B track
B336-1787105115/105165P
( 8 Springs )
( X1125A )
15 Rollers 
B336-1353
Colchester Combi K4
Harrison Alpha 550 U
163145/163215XC
( X1272A )
B336-1798163144/163213D
( X1273A )
B336-1799
Harrison Alpha 550 T163150/163210HRE+60
( X1262A )
26 Rollers in A track
13 Rollers in B track
B336-1789109127X/109175P
( 8 Springs )
( X1216A )
15 Rollers 
B336-1354
Colchester Tornado 80
Colchester Tornado A50
B7016FA7ETBLB313-6115B7014FA7CDBLB336-6116
Colchester Tornado 100
Colchester Tornado 110
Colchester Tornado A90
B7018FA7ETBLB313-6105B7017FA7CDBLB313-6106
Colchester Tornado 200
Colchester Tornado 210
B7022FA7ETBLBA-0140B7021FA7CDBLBA-0220
Colchester Tornado 220B7022FA7ETBLBA-0140B7020FA7CDB 80 daNB313-6122
Colchester Tornado 300
Colchester Tornado 310
B7026FA7ETBMBA-0230B7024FA7CDBLBA-0240

Tuesday, 12 September 2017

Ethernet to 4G Bridge using Raspberry PI and CDC Mobile Network Dongle


Here my notes on lessons learned

The old usb modem sticks present a storage device and serial device depending on the mode.
The newer devices present a CDC ethernet device with internal IP and web service. These are in my view easier to configure, since ppp wfdial configuration is not required.

Modeswitches are accomplished by device access through the device tree or usb node.

The utilities used for modeswitching


usb_modeswitch, sg_raw and eject utilities, as described on the arch linux site.

In my case I used a Huawei Modem E3737. Below the essence of my setup

OpenWRT Chaos Calmer 15.05. released: Mon, 16 Mar 2016 worked out of the box to do the modeswitch from ID 12d1:1f01 to 12d1:1442. The file /etc/usb-mode.json has the correct configuration strings to make this work.

Run
opkg update && opkg install usb-modeswitch

Before the reboot, usbmode -l displays the modem, after a reboot usbmode -l no longer displays anything, this was a bit confusing at first, when reading the howto guide on openwrt. However this makes sense since after the reboot the device ID to switch from is no longer found.

I then had to install the required packages
opkg update && opkg install kmod-usb-net-cdc-ether, udev, kmod-usb-net-rndis
 
Then a cat /sys/kernel/debug/usb/devices shows the correct driver Driver=cdc_ether. for the HUAWI USB Device.

Here the link to the site which helped me in calming the chaos in our wonderful inter-web library. How did people figure things out before the days of internet?

 
Now, if you type

ifconfig -a
you should see a new device there, in my case eth1. From there on it is simply going through the motion of configuring the correct gateways and IP ranges and plugging it all together.






Why there are so many different models on the market, anybody's guess is as good as mine :|

Below some links with useful information.

https://wiki.openwrt.org/doc/recipes/3gdongle

Serial Interface Modem Setup

https://josefsson.org/openwrt/dongle.html

http://b.minwi.com/2015/03/15/huawei-e303-3g-dongle-in-openwrt-barrierbreaker/


Chipmaster Gear Cutting

  Calculate all the possible gear combinations for the gear selector to cut a 15TPI thread: Imperial TPI C 5 24 20 Imperial TPI ...