May issue 20 PAGE PREVIEW of Model Engineers Workshop

7 32 .

No

A LATHE AUTO OILER

A System Suitable For Myford And Other Drip Oiled Lathes.

THE MAGAZINE FOR HOBBY ENGINEERS, MAKERS AND MODELLERS MAY 2023 ISSUE 327 WWW.MODEL-ENGINEER.CO.UK

3D Resin Printing in Your Workshop

We Review the Creality Halot One Plus

BOXFORD SPINDLE ACCESSORY A multi-purpose tool for a classic lathe.

USING TOOLMAKERS’ BUTTONS

An essential aid to accuracy in setting up.

D ISSUE: INSIDE THIS PACKE May 23

 HARDENING AND TEMPERING STEEL  A HOLDER FOR SHARPENING VARIOUS TOOLS  A NEW WAY TO SET GRINDING ANGLES.  THE KING OF MY WORKSHOP  LAMINATING WALLCHARTS  FIND OUT MORE ABOUT YOUR HOBBY!  A HIGH-SPEED THREAD STRIKING ATTACHMENT  PLUS ALL YOUR REGULAR FAVOURITES!

Get more out of your workshop with MEW

Join the conversation at: www.model-engineer.co.uk

EDITORIAL

Editor: Neil Wyatt Designer: Druck Media Pvt. Ltd. Publisher: Steve O’Hara By post: Model Engineers’ Workshop, Mortons Media Group, Media Centre, Morton Way, Horncastle, Lincs LN9 6JR Tel: 01507 529589 Fax: 01507 371006 Email: meweditor@mortons.co.uk © 2022 Mortons Media ISSN0033-8923

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On the

Editor's Bench The only Constant is Change!

By its nature, model and hobby engineering is an experimental hobby. It attracts creative thinkers with open minds. We are always repurposing things, stretching the capabilities of our equipment and looking for ways to make things, better, simpler or more flexible. When I became editor, it was my assumption that the hobby was fairly static; how wrong I was. For example, around then inverter controlled motors were becoming more affordable and it seemed everyone was fitting them to their machine (including me!)

This issue sees a review of a stereolithography or ‘resin’ 3D printer. It seems remarkable that this is the first time this technology has appeared in MEW, yet it’s only about tens years since such machines became a practical option for a hobby workshop. Five years or so ago I wrote a book on 3D printing, and at the time resin printing was so unusual for hobbyists I’m not sure I even mentioned it; even the original RepRap fused filament printer was invented only seventeen years ago!

In 2023 we have already featured several articles featuring 3D printing, chiefly for making enclosures, but this month’s Readers Tip has a particularly useful application.

It seems that a well-equipped hobby workshop now has a lathe, mill, pillar drill, grinder and a 3D printer! Embedded electronic are also commonplace – in this issue a project combines 3D printing and an Arduino to help make an automatic oiler for a 75-year old lathe design!

What’s next? Small plasma cutters are now getting so affordable they are sold in supermarkets! Laser cutters and engravers are becoming increasingly affordable, although something cutting more than wood still demands a hefty price tag. There are also small laser-based precision welders that promise an easy alternative to silver soldering for small fabrications.

I would be pleased to hear from readers who are trying out such machines. I’m particularly interested in reviews that signpost other readers to machines worth having and how-to articles that help people understand their capabilities and applications. That said, I also appreciate reviews and write ups of more traditional machines – whether modern lathes or antique ones!

Neil Wyatt

EDITORIAL CONT2RIBUTION

Accepted photographs and articles will be paid for upon publication. Items we cannot use will be returned if accompanied by a stamped addressed envelope, and recorded delivery must clearly state so and enclose sufficient postage. In common with practice on other periodicals, all material is sent or returned at the contributors own risk and neither Model Engineers’ Workshop Magazine the editor, the staff nor Mortons Media Ltd can be held responsible for loss or damage, howsoever caused. The opinions expressed in MEW are not necessarily those of the editor or staff. This periodical must not, without the written consent of the publishers first being given, be lent, sold, hired out or otherwise disposed of in a mutilated condition or, in any unauthorised cover by way of trade or annexed to or as part of any publication or advertising, literary or pictorial matter whatsoever.

This issue was published on June 17, 2022.

The next will be on sale on July 22, 2022.

May 2023

3

Contents 9 An Auto-Oiler for a Myford Lathe Myford’s drop oiling system is notoriously fickle. ulian almer has devised a system that means you don’t have to remember to put the oil flow on or off.

17

17 Sharpening Cutting Tools

acques Maurel completes his flexible accessories that extend the versatility of his sharpening attachment.

26 Artful Dodges

ohn Smith explains how to use toolmakers’ buttons to set up obs on your lathe.

28 The Morphing of a Tool

Matt Shaw tells the story of a multi purpose spindle mounted too for his oxford lathe that is easily adapted to other machines.

31 Review: The Creality Halot One Plus

The latest generation of SL printers promise outstanding quality at a similar price to D machines. eil Wyatt finds out how this machine from reality measures up.

40 The King is Dead! – Long Live the King!

Matt Shaw replaced his century old pillar drill with a new larke machine, switching over various modifications and beefing it up for obs beyond its original capacity.

ER Lathes.

AUTO OIL Other Drip Oiled A LATHE Myford And Suitable For

27 .3 No

46 From the Archives

59 Beginner’s Workshop

51 Upgrading a Mill with a High-Speed Spindle

31

This month we only nip back a couple of decades in our series celebrating 2 years of Model Engineer.

Simon Davies found his shop made spindle couldn’t take the extreme speeds he wanted to use in this issue he gets the spindle up and working and sees how it performs.

This month eometer looks at hardening and tempering.

A System

3D

ERS, MAKERS

FOR HOBBY ENGINE

AND MODELLERS

MAY 2023 ISSUE

O.UK L-ENGINEER.C

327 WWW.MODE

in Your Wor Resin Printing

THE MAGAZINE

kshop

s

One Plu Creality Halot We Review the

NDLE BOXFORD SPI ACCESSORY

pose tool A multi-pur lathe. for a classic

May 23

£5.75

KERS’ USING TOOLMATTONS BU ing up.

An essential

aid to accuracy

A NEW US TOOLS  PENING VARIO WALLCHARTS  ER FOR SHAR NATING INSIDE T  PLUS STEEL  A HOLD SHOP  LAMI ING ATTACHMEN AND TEMPERING  THE KING OF MY WORK ES. D THREAD STRIK  HARDENING GRINDING ANGL HOBBY!  A HIGH-SPEE WAY TO SET ABOUT YOUR sation at: FIND OUT MORELAR FAVOURITES! Join the conver r.co.uk nginee ALL YOUR REGU www.model-e

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Coming up…

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in our next issue ernard Towers makes a depth stop for collets.

E T RES W R S

E E TS

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Website www.model-engineer.co.uk Why not follow us on Twitter? twitter.com/ ModelEngineers hashtag #MEW

Regulars 3 On the Editor’s Bench

The editor is surprised ust how much things have changed in our hobby.

37 Scribe A Line

More news from our readers her in the and from around the world. We are always keen to hear from you – ust send an email to meweditor mortons.co.uk.

THIS MONTH’S BONUS CONTENT

50 Readers’ Tips

Log On to The Website for Extra Content:

60 On the Wire

isit our website to see Matt Shaw’s oxford Spindle Tool in action, and see more of the alot ne. www.model-engineer.co.uk

ur winner this month has a neat and tidy update on a popular modification. Send your tips to meweditor mortons.co.uk.

ews about the forum, and a computer generated contribution.

66 Readers’ Classifieds

This month’s selection of readers’ sale and wanted ads, carefully transcribed by eidi who can decrypt the most obscure handwriting!

ON THE COVER Our cover shows a ferocious Frost Dragon hanging over the resin vat of the Creality Halot One Plus resin printer.

27 .3 No

A LATHE AUTO OILER

A System Suitable For Myford And Other Drip Oiled Lathes.

Why is the world of model engineering still imperial? sks aul McDonough.

Simple case hardening recipe What’s a modern solution by choochoo baloo.

Oscillating Engine Simulator by ames Stanley.

Parting off using a powered cross feed y .

THE MAGAZINE FOR HOBBY ENGINEERS, MAKERS AND MODELLERS MAY 2023 ISSUE 327 WWW.MODEL-ENGINEER.CO.UK

3D Resin Printing in Your Workshop

We Review the Creality Halot One Plus

Come and have a Chat!

BOXFORD SPINDLE ACCESSORY A multi-purpose tool for a classic lathe.

May 23

£5.75

USING TOOLMAKERS’ BUTTONS

s well as plenty of engineering and hobby related discussion, we are happy for forum members to use it to share advice and support. ome and oin us – it’s free to all readers!

An essential aid to accuracy in setting up.

INSIDE THIS PACKED

ISSUE:

 HARDENING AND TEMPERING STEEL  A HOLDER FOR SHARPENING VARIOUS TOOLS  A NEW WAY TO SET GRINDING ANGLES.  THE KING OF MY WORKSHOP  LAMINATING WALLCHARTS  FIND OUT MORE ABOUT YOUR HOBBY!  A HIGH-SPEED THREAD STRIKING ATTACHMENT  PLUS ALL YOUR REGULAR FAVOURITES!

Get more out of your workshop with MEW

May 2023

Other hot topics on the forum include:

Join the conversation at: www.model-engineer.co.uk

L SSI IEDS E TR

S

S RI E

R

I E S

LIERS

7

Auto -Oiler

An Auto-Oiler for a Myford Lathe Julian Palmer struggled to set the drip oilers on his ML7 lathe, and was fed up of finding the machine standing in a puddle of lubricant. He decided to design an electronic auto oiler system and get rid of the problem once and for all. It’s potentially suitable for use with any drip-oiled lathe.

1

System components prior to installation.

H

aving owned my Myford ML7 for some 30+ years I’ve never quite mastered the vagaries of the spindle drip lubrication system. I found it nigh on impossible to set a regular drip at a suitable frequency and was always forgetting to shut them off resulting in pools of wasted oil under the lathe.

These issues combined with fitting an inverter and three phase motor capable of running at higher speeds set me wondering if such hit and miss lubrication was adequate. fter much pondering, I came up with the idea of using a peristaltic pump driven by a stepper motor turning a number of steps to deliver a metered quantity of oil to each bearing, the stepper timing being controlled by an rduino, a small inexpensive

May 2023

microcontroller. fter several prototypes and many hours of testing, it worked to a degree, but I wasn’t happy with the repeatability nor my ability to write code for the Arduino.

At this point I turned to a very good and long suffering friend who, to say the least, is a bit of a whi when it comes to programming. Mark had previously helped me sort out problems I was having with my electronic lead screw by writing software that counted encoder pulses and highlighted when the system was picking up spurious signals, a fantastic bit of work without which I’d have never got the system working accurately.

Now with some brains on the project things could progress to add more features and allowing a change to DC motors (although we have retained

the code for stepper motors if people wish to use them). This is a relatively cheap, fully automated, oiling system which I believe solves most of the problems many people experience with mechanical oilers.

The system operates as follows: An Arduino controls two motors which drive two separate peristaltic pumps.

The pumps draw oil from a small oil tank and pump oil to two sight glasses mounted on each spindle bearing which replace the original drip oilers. A thin pipe at the top of the sight glass drips oil into the bearing and triggers a photo interrupter I sensor to confirm that the bearing has been oiled. The system will give an alert if no drip has occurred. Photograph 1 shows all the components which comprise the system. ›

9

It should be possible to build this for around the cost of new manual oilers.

The system can work in three modes 1) Elapsed time mode (Default).

Oiling occurs at a preset frequency irrespective of the lathe running.

Whenever the Arduino is powered up oiling occurs at preset time intervals until power is switched off. This is default mode and relies on the operator remembering to switch it on and off.

2 owered time, or power on mode.

Oiling occurs at a preset frequency whenever the lathe is running. A signal to the Arduino whenever the lathe starts and stops initiates oiling.

This set up will require the lathe to have both an isolator switch and a start/stop switch. Turning on the lathe isolator also powers the Arduino which does an initial oiling prior to the lathe running. It then oils at preset time intervals whenever the lathe is running.

3 Work done or machine work mode.

Oiling frequency based on lathe rpm.

An isolator and a start/stop switch are required for this mode which again allows for oiling prior to the lathe being started. A tachometer or encoder is required or a photointerrupter (PI) sensor similar to the drip sensor can be used. With this mode, drips are delivered based on a

preset number of spindle revolutions so the faster the spindle is turning the more frequent the oiling. This is the system I built and, in my opinion, is to be preferred as the bearings are oiled more frequently at higher speeds.

The system has an alert function which triggers if a drip is not detected after a preset number of seconds or revs, thus indicating if there is a blockage or oil has run out. Number of drips per cycle can be preset. If required, the rduino sketch can control up to D motors.

I employed the use of a somewhat ageing 3D printer, but it would be quite possible to build a system using alternative components such as hobby boxes and to machine the pump to motor adapter.

Prospective builders not familiar with microcontrollers or electronics should not be put off by their use. The electronics are really quite simple if you follow the circuit diagram and Mark has written some very clever Windows software which creates the sketch for you to subsequently compile and load using the rduino software. full download of rduino sketches, the software to write sketches, an in depth wiki explaining the rduino library that Mark put together, electrical schematics, STL files for 3D printing and a bill of materials with prices current at the time of building are all available from

Marks it ub at github.com naylom OilerLib. ll the code on Marks it ub is freely available without restrictions on use.

The bill of materials (BOM) lists all the major components required for the project. Parts may well be found cheaper with a little hunting around. I sourced most of my components from the

2

Sight glass showing PI sensor fitted to the slot in the acrylic tube, oil feed tube at the top and a drip forming on the drip pipe.

3

Sight glasses fitted to the spindle bearings.

10 www.model-engineer.co.uk

Model Engineers’ Workshop

Auto -Oiler internet and I’ve assumed that, as typical hobby engineers, prospective builders will have all the usual bits of scrap, fixings and hoarded items available to complete most mechanical parts.

Sight glasses These are a relatively easy turning exercise. I made mine from aluminium bar and 15mm OD acrylic tube. The thread used between the Acrylic tube and aluminium housings was x 0.75mm. A slot is milled in the acrylic to accept the PI sensor such that it’s a tight fit and held snugly, photo 2 and 3.

The small-bore tube which produces the drips is super glued into a hole in the top of the sight glass and, if long enough, can be used to strengthen the hose tail by running its full length. The one critical dimension is between the end of the drip tube and the top of the PI sensor which should be no less than 3.5 - 4mm. This allows a drip to leave the drip tube completely before triggering the PI sensor.

Acrylic tube of the appropriate dimensions is readily available online as is the drip tube which was obtained by buying a couple of dropper bottles which come with a selection of interchangeable no les.

I used the .2 mm D no le which, as best as I can measure, has an ID of

mm. Stripping the plastic off the tube in preference to cutting the tube should give su cient length to reinforce the hose tail. A bonus of buying the tubes this way is that you get a couple of handy dropper bottles for cutting fluid or other duties.

The male thread at the bottom obviously needs to suit the bearing to which you are fitting it and in the case of the Myford is S . Lock nut will be required to fix it in position with the I sensor located to the rear of the lathe.

4

PI sensors and cables I used S cables as these have the correct number of cores, are cheap and are readily available as are the sockets into which they plug. The PI sensors are ref number 2 also readily available online. To pre-empt any questions – yes they seem to work ust fine doused in oil.

Wires were soldered to the PI sensor and it was then potted with hot melt glue using a simple mould machined out of a suitable plastic block. e careful not to use too much hot glue when potting as it’s possible to fill the sensor completely and obscure the LED and phototransistor. If you buy fabric braided cable as I did, putting a drop of superglue on the braid before cutting keeps everything neat and tidy until you pot it, photo 4.

PI sensor with cable attached in plastic mould prior to potting with hot glue.

Motors, pumps and housing The peristaltic pumps available online are supplied with a direct drive motor which is way too fast for this duty, photo 5. I replaced the motors with 12vDC geared motors type S30 available from the same sources. An adapter between pump and gearbox was incorporated into the 3D printed housing design.

Alternatively stepper motors type 28BYJ-48 can be used along with the driver board type ULN2003. A wiring

5

Rather poor-quality 3D printed motor and pump housing complete with oil tank mounted on the Myford belt guard.

May 2023

›

11

3D printed Motor and pump housing.

schematic for the stepper motor version is available as part of the download from Marks it ub.

I 3D printed my housing, photos 6 and 7, but if you don’t have access to a 3D printer it would be an easy machining ob to make an adaptor and mount everything in a proprietary pro ect box.

A simple drive adapter needs to be made to connect the motors to the pumps, photo 8. The thin end directly drives the pump rollers and the slot engages with the motor gearbox shaft.

In testing I noticed a slight erratic rotation which, although it worked ust fine, I believe is due to this coupling. It’s effectively half an ldham coupling, so as an improvement I’d suggest a full Oldham coupling could be better employed.

The pump housing contains a small bread board’ and a couple of S sockets, photo 9. The bread board is a means of connecting the S sockets used for the I sensors, and the motors to a multicore cable running to the Arduino. It’s also a convenient location to mount some of the electrical components. I utilised spare cores in the multicore cable to remotely locate a red alert LED in the pump housing.

Oil tank The oil tank in my design is made from 20mm acrylic tube glued to a printed manifold and the assembly glued on to the motor housing, photo 10. Making it separate to the housing made for easier printing. ll parts were printed in S which glues extremely well with acetone or drain pipe solvent adhesive.

12

www.model-engineer.co.uk

7

Underside of Motor and pump housing showing tube arrangement and USB sockets for PI sensor connections to the rear.

8

New, turned drive shaft. The thin end pushes between the roller of the peristaltic pump to give a direct drive and the slotted end mates with the motor gearbox output shaft.

Brass hose tails were turned with an M thread, heated up and screwed into M modelled threads in the manifold, photo 11. If you get the temperature right and don’t mess them around whilst cooling, this fixing method forms an exceptionally strong and oil tight oint. simple press fit lid was printed to cover

the top of the tank, photo 12.

I had considered other ways of making the oil tank. Top of the list was a Tic Tac sweets container which is transparent and has a ready-made cap. It seemed a little large at the time, so I made my own.

In retrospect and with the experience of use, a larger tank would be preferable,

Model Engineers’ Workshop

Auto -Oiler 10

Pump and motor housing showing the bread board which serves to connect the motors, USB sockets for the PI sensors and the multi core cable running to the Arduino.

It also offers a useful location for some of the resistors. A Red LED was fitted to indicate alert condition.

and the idea may also be of use to those without a 3D printer.

simple 3D printed bracket was made to mount the rduino in an existing electrical cabinet containing other lathe control gear. A cut out in the enclosure was made which allows the S socket on the Arduino to be accessed. The multicore cable connecting the pump housing to the rduino was fitted with a cheap multi pin plug and socket to access the enclosure.

I mounted the Arduino remotely from the lathe, but provided the wiring schematic is followed, it doesn’t really matter where the various electrical components are located.

Arduino and screw shield

Electronics

An Arduino Uno is used to control the system. We’ve only tested it using a no and as Mark has employed some low level register instructions, it may not run on other micro controller boards. The Uno and its various clones (Arduino products are open source and hence many clones are freely available) are cheap and readily available micro controllers which are more than capable of handling this relatively simple code.

A screw terminal shield (a PCB that plugs into the Arduino and has screw terminals for wire connections) is well worth the investment as it allows mounting of various components and makes for easy connecting to the Arduino. n my rduino shield, I fitted two green LEDs to indicate when each pump motor is running and a red LED for the alert indication.

ot my area of excellence, so apologies if anyone spots any errors. The circuit does, however, appear work satisfactorily!

Two electrical schematics, one for the DC motor version and one for the stepper version are available on Marks it ub. The D motor version shows two options in blue dashed boxes top left. ne is for Work done mode’ and the other for power on or powered time mode. You need to use the version suited to the system you are building. Do not use both!

Component part numbers and values are shown on each schematic.

Since building the oiling system and first writing this article, I have realised an error with my electronics. The original design had the motor relays driven directly from the Arduino output pins.

11

M5 brass hose tail.

May 2023

3D printed oil tank with brass hose tails fitted prior to glueing to the motor and pump housing.

12

Oil tank fixed in place and fitted with a with a simple push fit 3D printed cap. lthough my build works ust fine and continues to do so after a year or so, the relays draw more current than the Arduino output pins are rated for. A quick fix for this is to use a relay module.

These are readily available and can be had for just three or four pounds. A two relay module is shown, suitable for

13

›

relays. The 5V supply from the Arduino board is more than capable of providing su cient current for this duty. The electronic schematic shown in this article includes the relay module and the downloadable version on Marks it ub has been up dated.

The schematic, g , shows specific pins being used but any digital pin can be used for any duty provided it’s correctly detailed in the rduino sketch.

Where you locate the various components will depend on your build but follow the schematic and everything should work. sing shielded cable with

14

13

Lash up of an RPM sensor. An aluminium angle is clamped to the spindle with a jubilee clip and a H92B4 PI sensor (as used to monitor the drips) is clamped to the head stock casting.

Pulsed signal for spindle revs This is only required if using work done’ mode. On my system I used a spare phase from a spindle driven encoder fitted for my electronic lead screw. owever for completeness and to assist others who may be interested in implementing the work done’ mode I made a quick lash up of an encoder using the same PI sensor as used to monitor the oil drips and tested it with Marks ilerLib sketch to in excess of 1200 rpm. The cost of this arrangement is minimal and it seems to work ust fine.

My test version of this pulsed signal really was a lash-up. I clamped a bit of bent aluminium to the collar on the left of the spindle ‘V’ pulleys with a hose clamp, and I fixed the I sensor on the front edge of the head stock casting using a clamp, photo 14. I’m sure prospective builders could come up with a far more elegant solution.

rduino s etc and so ware

Arduino ‘screw shield’ with Arduino Uno mounted behind, housing the motor relays and some of the electrical components. There is a green LED to show each motor is running and a red LED to indicate an alert condition.

running two motors. If you’re running more motors purchase a board with the correct number of relays, photo 13.

These relay boards take the low current Arduino signal and use an additional 5V supply to switch the

the shield connected to Arduino ground for all external cable runs will help guard against any disruption in digital signals.

s with electronics, this is not my area of excellence. ll the sketches and software for this system were written by Mark without whose expertise this pro ect would not have been possible.

Future addition Nextion touch screen control

Powered from lathe run switch both FWD & reverse KX To suit supply

C 1

3

D4 Alert LED

GND GND GND

UX Optical switch H92B4 A C

2

4

R5 100R

E

RX 100R

RX 10K

SCL/A5 SDA/A4

5

Or

Work Done Mode (drip frequency based on lathe revs) This mode requires a pulsed signal from an encoder, tachometer or as shown below a photo interrupter as used to monitor the oil drips. The circuit below has been tested with the Oiler_lib sketch & works fine up to 1200rpm. Other encoders or tachometers may require a different circuit

D13 D12 SCL/A5/D19 D11 SDA/A4/D18 D10 A3/D17 D9 A2/D16 D8 D7 A1/D15 D6 A0/D14 D5 D4 AREF D3 IOREF D2 D1/TX D0/RX RESET

Power On Mode (drip frequency based on time when lathe is running)

RX TX GND +5V 3.5” Nextion display

VIN 3V3 +5V

D1 Diode 1N4148

PS1 Power supply 12V DC 4 3 L DC+ 5

DC-

N

2

A1 Arduino UNO R3 GND

RX 10K

+5V +12V

K1 G5LE-1

4

1

3

K2 G5LE-1

12 3 4 2

2

VCC IN1 IN2 GND

5

4

1

+12V

Notes: 1. Schematic shows specific pins employed as inputs & outputs, but using the Oiler_lib sketch & OilerBuilder software any digital pin may be used for any function provided it’s correctly defined in the Arduiono sketch.

5

2. Resistor values are what worked on my oiler system. Values may need to be changed to suit alternative components & alter LED brightness etc.

3

3. The pulsed signal shown on pin 12 for spindle revs can be created using a photo interrupter H92B4 as used to monitor oil drips. The circuit shown has been tested up to 1200rpm. Alternatively existing tachometer or encoder signal could be used, but this may require a different circuit.

5V relay switch board module D5 Motor 1 run LED +1

M2 Geared DC Motor S30K + 1

M

M

U1 Optical switch H92B4 A C

U2 Optical switch H92B4 A C

330R R6

R1 100R

D6 Motor 2 run LED

M1 - 2 Geared DC Motor S30K

C

E

330R R7

- 2

R2 100R

C

E

5. Motor direction can be changed to suit required pump rotation by swapping + & connections on either motor.

R3 10K R3 10K

Figure 1

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4. The Nextion touch screen shown top right is not yet implemented but may be a future development. Without touch screen various parameters may be adjusted in the sketch & uploaded to the Arduino in the normal way.

Lathe Auto-Oiler Schematic With DC Motors And Relay Module

GND +5V

Model Engineers’ Workshop

Auto -Oiler or those with no experience of things rduino, there are numerous tutorials and how-tos available on line which explain things far better than I’m able, but as an overview for this specific pro ect, you’ll need to down load the free rduino software known as rduino IDE from www.arduino.cc en software. hoose an older release, rduino IDE . . ’. Select the version suitable for your operating system, download and install it. The reason for downloading this older version of the rduino software is that it was current when Mark wrote the ilerLib sketches and software so we can’t guarantee that later releases will allow for the automatic placement of the library or completed sketches. ext download Marks software from github.com/naylom/OilerLib. lick the green ode’ button, select ‘Download Zip’. Open the Arduino software and click Sketch Include Library dd . ip Library’. Locate your download from Marks it ub called ‘OilerLib-master’ which will usually be in your Downloads’ folder and click pen’.

In a blue bar towards the bottom of the window the rduino software should reward you with a confirmation that a library has been added to your libraries. ext you need to select the correct Arduino board and communication port. o to Tools oard’ and select rduino no’. Then, with the rduino no board connected to your computer using a suitable S cable, go to Tools ort’ and select the correct port. The Arduino software should have detected your board, and you’ll see something similar to M3 rduino no ’ click this and you’re all set to go.

OilerBuilder app. or the more experienced, you can build your own rduino oiling sketch using the examples included in the ilerLib release and Marks extensive it ub Wiki. ext step for the less experienced like myself is to run Marks iler uilder app which will write the rduino sketch for you.

In your file manager go to Documents rduino ilerLib . . Examples’ and locate an application called ‘OilerBuilder’. lick on this and you’ll most likely get a warning because it’s by an unknown publisher’. Ignore this and after a splash screen you’ll be presented with a window with various tabs where you can detail

May 2023

the system you wish to build by entering a number of choices.

For demonstration I’ll show OilerBuilder populated for the system I built, a two D motor system controlled by lathe rpm, but mention alternative variations as I run through. This example uses the pin numbers shown on the electrical schematic.

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Motor 1 tab This first page, photo 15, defaults to a DC motor and relay setup but at the top is an option to set up a 4-pin stepper motor if preferred.

‘Inputs Pin#’ is the pin to which you’ve connected the output from the PI sensor pertaining to motor 1.

‘Inputs PinMode’ selects INPUT or INPUT_PULLUP. The electrical schematic shows a pull down resistor so INPUT is appropriate, but if you are using an alternative circuit internal pull up resistors can be set here if required.

‘Inputs # Drips to stop motor’ is pretty self explanatory, it’s the number of oil drips required from this motor each time it oils.

‘Inputs Debounce time (ms)’ This setting determines the minimum number of milliseconds required between valid signals from the Photo Interrupter. y setting a minimum value, it prevents duplicate or spurious signals implying a drip has occurred when it hasn’t. If for any reason you find that one drip is being recorded as multiple drips this value can be increased.

‘Outputs Pin 1#’ is the output pin which drives the relay to operate motor 1 If a stepper motor is chosen there will be four outputs pins to set along with the required direction of rotation.

OilerBuilder Motor 1 tab showing setting for my system.

OilerBuilder Alert tab showing setting for my system. Ignore the red note regarding Multiples.

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Motor 2 tab

OilerBuilder Oiled Machine tab showing setting for my system.

This is a repeat of motor , but obviously with the pin numbers to suit motor 2.

Motor tabs 2 are not changed unless you are oiling more than two locations.

Alert tab Shown in photo 16. ‘Alert pin#’ sets which pin gives the alert signal.

‘Level held at during alert’ dictates how the alert pin behaves. igh means it outputs 5v in alert condition and low means it sits at 5v all the time there is no alert, dropping to 0v in alert condition.

‘Alert threshold’ sets the number of seconds or revs (dependant on later

configuration should pass between the start of an oiling operation and the alert being triggered. Be aware that the pumps will take time to produce a drip so don’t set this number too low or the system will trigger the alert before the drip has occurred.

Please ignore the red note about setting multiples. This was a feature we removed and omitted to delete the note … apologies!

Oiled Machine tab ere, photo 17, you can set the mode

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Arduino sketch generated by Marks OilerBuilder app.

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OilerBuilder Final tab showing setting for my system. of operation. Either ower on’ or Work done’ mode. You can enter details for both modes, but in the final tab you specify which mode you wish to use. If neither is selected i.e. both input pins are set to -1 the system will run in default mode where the system oils every X number of seconds all the time the system has power irrespective of what the lathe is doing.

‘Power on’ mode uses a signal to say the lathe is running, typically an output from a relay operated by the lathe start/ stop switch. The pin to which this signal is connected is entered into the ‘Input in ’ box.

‘PinMode’ selects INPUT or INPUT_ PULLUP. The electrical schematic shows a pull down resistor so INPUT is appropriate, but if you are using an alternative circuit internal pull up resistors can be set here if required.

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Sig Level’ dictates how the pin should recognise the input signal. igh means that 5v will indicate the lathe is running and 0v indicates the lathe is stopped.

Low means the pin operates in the opposite fashion to above i.e. 0v means the lathe is running and 5v means the lathe is stopped.

Work done’ mode uses a pulsed signal for spindle speed. The signal needs to be one pulse per revolution of the lathe spindle.

The pin to which this pulsed signal is connected is entered into the ‘Input Pin ’ box.

‘Input PinMode’ selects INPUT or INPUT_PULLUP. The electrical schematic shows a pull down resistor so INPUT is appropriate, but if you are using an alternative circuit internal pull up resistors can be set here if required.

Final tab This tab, photo 18, is titled Set Motor Restart Mode’. ere you set the event that triggers motors to (re)start oiling.

Not all options will be visible depending on previous settings, but the three options are: n elapsed time secs ’. Default mode, where the system restarts the motors after a configured number of seconds.

Irrespective of what the lathe is doing. n powered time secs ’. System counts seconds that the lathe has been running and when this reaches the

configured limit it restarts the motors n machine work units ’. System restarts the motors after a configured number of revolutions of the lathe spindle.

Select whichever mode you are using then and in the Threshold’ box, enter the number of seconds or revs. between oiling operations. inally Sketch pathname’. If you have the rduino software already installed, the iler uilder software will have created the sketch in a folder called ‘OilerBuilder’ in the standard Arduino sketch directory i.e. in the same place the rduino software normally stores sketches .

If this cannot be found it will create the iler uilder sketch in the TEM ’ directory.

You can change the path to another destination if you wish.

If you are using the ‘Arduino Create’ web editor or the new ‘Arduino IDE 2.0 pc application’, iler uilder will not know where the sketches are normally kept and will, by default, put it in the TEM folder or your chosen location.

That should be it, click reate Sketch’.

You should get a small pop-up with an option to open the folder where the sketch is located, or you can open it via your file manager. nce open, you should see a sketch similar to photo 19. You can change any of the define parameters in the sketch.

Each has a description of its purpose. lternatively you can make changes by running the iler uilder software again and create another sketch which will overwrite the first. pload it to your rduino by clicking the upload button (a right pointing arrow in a circle top left of the rduino window. The rduino software will compile the sketch and upload it to your board.

Power up the system and the pump motors should run before you start the lathe. Each motor will run until its PI sensor has seen a drip. First priming the system could take some time as the pumps only produce a small flow and have to fill the interconnecting tubes prior to producing a drip. fter this, whichever mode of operation you choose should run automatically. All you have to do is to remember to top up the oil tank.

Model Engineers’ Workshop

Sharpening Cutting Tools

Sharpening Cutting Tools - Part 2 Ha ing used his attachment to sharpen taps and dies ac ues aurel finishes some further accessories (part numbers follow on from the previous articles) for sharpening other types of tools.

7 P

30°

Cone apex

Conical wheel

Ød

M

30°

d/2

h

D/ 2

_

_ Tool Cylindric wheel

Figure 8 8

Notes on Drill Sharpening Some adjustments are possible by turning the drill (using sideways movement of the cam). Ideally the result is good if the cutting edge of the drill is horizontal when just touching the wheel at the end of the sharpening

May 2023

process. This is function of the amount of material to remove, if the hand sharpening (always necessary before the machine one, see my article in MEW issue 245) has been well done, just a few tenth of mm are to be removed and don’t hesitate to grind off the heel as

the heel is of no use, takes time to grind and wears the sharpening wheel for nothing (the heel is the bête noir for drill sharpening). If ever the cutting edge is lower than horizontal, the clearance will be smaller, moving the cam to the right will solve the problem.

If you use a cylindrical or conical grinding wheel, you’ll have to adjust the spindle axis height relative to the (horizontal) grinding wheel axis to get the right clearance angle, see g and photo 7 showing a conical CBN wheel the great advantage of which is the cold cutting action, it is also used for point splitting. P otograp shows another possible position for drill sharpening with the CBN wheel (as the wheel angle is 30°) this relative angular position for the spindles is the same (but not the height) as the one necessary for drill point splitting (see later).

In these cases, h = (d/2)tan_ for a cylindrical wheel and d cos tan_ for the conical wheel (having 30° for half cone angle).

It is possible to sharpen drills having 0 point angle, 2 clearance is su cient if they are used for countersinking, to avoid chatter.

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44

9

32

6.2

10

20

4

Thickness 2mm

Figure 9

r2 90°

to 247), photo 9, to replace the dividing blocks.

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Drill point splitting See p otos and The principle is the same as the one described in MEW issue 256. The advantages are: The dividing (the attachment is only used for dividing in this case). And you don’t have to alter the “Z” setting when changing the drill diameter as was the case with dividing blocks.

The “drill setting” is made directly on the spindle.

The use of a CBN wheel gives an amazing “cold cut” even for a great amount of stock removal.

The attachment must be made for the drill position adjustment, see g . The various numbered parts are shown in later figures.

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ac ine and attac settings:

It is also possible to use the attachment as a dividing spindle, using a special cam, g with a vee notch

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lodging the dividing stems, this allows 4-facet sharpening or the method described in my article (MEW issues 245

ent

1 Set the spindles in the position shown on photo 11, the axis distance is adjusted for 35° angle between the drill axis and the splitting groove (see g ).

2 Set the dividing cam fig. and use two indexes in the dividing collar.

Set the drill stop 29 at about 23mm from the collet, for the grinding wheel (working diameter 68mm) not to touch the collet closing nut (diameter 42mm).

4 Set the adjusting pin, about 30mm protruding out from the collet, and take a “0” along the Y axis, photo 12.

5 Free the adjusting pin, push it on the drill stop 29 and close the collet see p oto . Turn then away the stop 29 in a downwards position.

Model Engineers’ Workshop

Sharpening Cutting Tools While closing the collet nut, it’s necessary to push the adjusting pin from the back (any piece of rod between say 10 and 15 mm in diameter and about

setting a drill for splitting.

6 Tangent the adjusting pin along the X axis, photo 14, and set a machine stop for the table movement (X axis). Remove the

100mm long will do the job) to maintain the contact with the stop as there is a slight backwards movement when collet closing. This must also be done when

D

A

30

D 24

25

Mirror

27

A

B

B

23

22

29

26 28

Stop

Figure 10

Point Splitting Attachment

13

h

35°

ØD

h = (D/2) x cos 35° = 0.41 x D

Figure 11 12

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May 2023

19

16

15

M6

17

4

Ø8

100 7

5

22. Bracket Rod

Figure 12 M6

B

Ø2 8

adjusting pin, you are now ready for drill point splitting whichever its diameter.

It is worth making a fine ad ustment of the stop on the first drill to be split pointed.

A

A

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B

10

3

1 From the previous zero position, move the table axis to the left for drill loading, and the Y axis backwards by about 5mm.

2 Set a drill in the spindle, push it on the (previously reset) stop 29, photo 15, set the chisel edge vertical and turn the drill by about 20° in its cutting direction (to get a self-centring point) don’t close the collet now. Turn part 24 for the mirror to be in front of the drill (ball lock, see photos 16 and 17) verify that the chisel edge is in the right position (adjust the angular position if necessary), reset the stop and close the collet (see previous note). Then turn the stop 29 into a downwards position.

The chisel edge can be set vertical only for drills having a point end after sharpening as is the case with the

Ø8

Routine for point splitting:

10 90°

Ø6

23. Indexing Collar

Figure 13

Model Engineers’ Workshop