Model Engineers Workshop June 2024 issue **20 PAGE FREE PREVIEW**

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A FLANGE MOUNTED ER32 CHUCK An accurate and robust design for long workpieces.

THE MAGAZINE FOR HOBBY ENGINEERS, MAKERS AND MODELLERS JUNE 2024 ISSUE 340 WWW.MODEL-ENGINEER.CO.UK

AN ADJUSTABLE PLATFORM Nicholas Farr’s solution to providing an accurate level surface.

SEND US YOUR WORKSHOP TIPS UK Readers can win Chester Machine Tools Vouchers.

A TOOL AND CUTTER GRINDER An easy and economical design from Stewart Hart.

D ISSUE: INSIDE THIS PACKE

June. 24

 UNDERSTANDING MILLING SPEEDS AND FEEDS.  A WALL MOUNTED WORKSHOP CRANE.  MICROMILLING – AUTOMATING MOVEMENTS.  A SIMPLE LATHE BED STOP.  MAKING GEAR SPROCKETS.  EXTENDED STEM FOR DIAL TEST INDICATORS.  A MECCANO LANCASTER.  FREE HOBBING - SIMPLE GEAR CUTTING.  A VIBRATIONAL CLEANER.  PLUS ALL YOUR REGULAR FAVOURITES!

Get more out of your workshop with MEW

Find out more 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 © 2024 Mortons Media ISSN0033-8923

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On the

Editor's Bench MACHINE TOOLS GIFT WIN CHESTER VOUCHERS WITH YOUR TOP TIP!

rated chair is essential., as is regularly stretching the legs.

Taking a look at the contents of my first issue, number 215, May 2014, it’s very similar balance of articles to that we see now. There MAY 2014 Join our online community www.model-engineer.co.uk are three ‘constructional’ articles, WEEKEND from a simple lathe stop (see the PROJECT A TAILSTOCK archive pages in this issue) to an DIGITAL READOUT ambitious raising block for the Warco VMC milling machine, via a between centres boring bar.

COVER FEATURE There are also ‘techniques’ articles: ON THE grinding radiused endmills, parting EDITORʼS BENCH MEET THE blade choices, guidance for beginners NEW EDITOR and error-free indexing. There are RAISING BLOCK ERROR FREE INDEXING IMPROVING FOR A VMC MILL WITH BRIAN WOOD YOUR CHUCK KEYS ‘modification’ articles looking at a Myford Super 7 and a Unimat SL. I was interested to see that though there are no 3D printers, THE MAGAZINE FOR THE HOME WORKSHOP MACHINIST an ongoing Beginners’ CNC series continues. There’s also an article on workshop lighting that features Ten years and several chairs the now obsolete compact fluorescent later… bulbs and what appears to be a very This morning I realised that the last issue primitive LED spotlight. Some things of Model Engineers’ Workshop, number change quickly!

339, marked the tenth anniversary of I’m glad to say that this anniversary my taking up the editorial chair. In fact, also sees me becoming more active I’ve worn out at two office chairs and I’m in my workshop again, as I have on my third, so they seem to have a life effectively reached the end of a long expectancy of about five years. I should house refurbishment. say, having a proper ‘twenty-four-hour’ 15 .2 No

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EDITORIAL CONTRIBUTIONS 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.

Neil Wyatt

This issue was published on 15 May 2024 The next issue will be on sale 21 June 2024

June 2024

3

Contents 9 The PottyEngineering Cutter Grinder

Stewart Hart describes a ‘quick and easy’ design to build a grinder to restore your blunted milling cutters.

39

15 3D Printing Workshop Ideas for Beginners

Robert Walker shares several practical ideas for printing workshop accessories.

20 An Adjustable levelling Platform

In our cover article, Nick Farr demonstrates how to make a stable, accurate base for jewellery or pocket type digital scales.

27 NOT An Ultrasonic Cleaner

eoff heasby makes a basic but effective vibrating cleaner.

29 Getting the most out of your Brushless Mill - Part 2

his time ason allamy looks at using shell end mills and face milling cutters, with particular attention to speeds and feeds.

32 From the Archives

his month, another stop, but this time for lathe beds.

34 Handling Heavy Lathe Accessories and Parts

Paul Zeusche explains how he deals with changing chucks and other accessories for his large lathe.

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39 How to Build a Lancaster Bomber!

Without a usable workshop to keep him occupied, Mark Noel turned to a Meccano kit of this iconic aircra

40 Tales From the Workshop

he extraordinary story of arry rindell Matthews and his curious inventions.

ERS, MAKERS

AND MODELLERS

JUNE 2024 ISSUE

a ues Maurel improves the versatility of a dial test indicator with a simple, reversible, modification.

52 Beginner’s Workshop

63 The John Stevenson Trophy 2022

his month Mike ilby looks automating the various movements of the micro-milling machine. his month eometer looks at roller chainsagain, with tips on making your own sprockets.

Michael Cox makes an accurate spindle mounted holder for ER32 collets.

Readers are invited to enter the workshop competition that puts practicality and function ahead of appearance.

64

O.UK L-ENGINEER.C

FOR HOBBY ENGINE

58 Lengthening a DTI stem

59 A Flange Mounted ER32 Chuck For The Minilathe

An accurate

THE MAGAZINE

Stub Mandrel shares his approach to making worm and wheel gear pairs.

42 Micro-Milling

ER32 CHUCes.K E MOUNTED piec A FLANGand for long work robust design

40

54 Free Hobbing

340 WWW.MODE

E PLATFORM AN ADJUSTABL to providing

SUBSCRIBE TODAY!

solution Nicholas Farr’s el surface. an accurate lev

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R SEND US YOU S WORKSHOP TIP

can win UK Readers hine Chester Mac s.

Tools Voucher

June. 24

£5.85

TER GRINDER A TOOL AND CUT from omical design An easy and

econ

.

Stewart Hart

ISSUE: PACKED

CRANE. TED WORKSHOP  A WALL MOUN BED STOP. E AND FEEDS. NG SPEEDS SIMPLE LATH S. NDING MILLI MENTS.  A TEST INDICATOR  UNDERSTA MATING MOVE STEM FOR DIAL CUTTING. LING – AUTO  EXTENDED GEAR  MICROMIL SPROCKETS. ING - SIMPLE S! GEAR HOBB URITE NG  FREE  MAKI LAR FAVO LANCASTER. YOUR REGU at:  A MECCANO L CLEANER.  PLUS ALL Find out more ngineer.co.uk  A VIBRATIONA

IS INSIDE TH

Get more out of

6

your wo

W rkshop with ME

See page 24-25 for details.

www.model-e

www.model-engineer.co.uk

Model Engineers’ Workshop

M

M

Coming up…

M

Visit our

in our next issue In our next issue Marcos Diniz makes some oversize vice jaws.

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

Regulars 3 On the Editor’s Bench

he ditor has a bee in his bonnet over cheap blades.

26 Readers’ Tips

Our winner this month has a suggestion for making lathe chuck keys kinder on the hands. Send your tips to meweditor@ mortons.co.uk, you could win a prize.

50 On the Wire

his month brings news of solar power for Africa.

printed chuck aws and floating

56 Scribe A Line

THIS MONTH’S BONUS CONTENT Extra Content! ee the video which accompanies ason allamy’s article on speeds and feeds for milling here, it’s valuable for anyone using larger cutters, whether your mill is brushless or not.

In this month’s postbag more feedback from readers, including information on thread chasing. We are always keen to hear from you – send an email to meweditor@mortons.co.uk.

https://www.model-engineer.co.uk/forums/topic/getting-the-mostfrom-you-brushless-mill/

65 Readers’ Classifieds

Hot topics on the forum include:

his month’s collection of readers’ for sale and wanted adverts.

ON THE COVER Our cover features Nicholas Farr’s adjustable platform to ensure reliable results when using electronic scales. See more details on page 20. and download the files from www.model-engineer.co.uk.

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Lifting a Myford S7 hat’s the best way to rig a sling to li a heavy lathe y eter impson .

A FLANGE MOUNTED ER32 CHUCK An accurate and robust design for long workpieces.

THE MAGAZINE FOR HOBBY ENGINEERS, MAKERS AND MODELLERS JUNE 2024 ISSUE 340 WWW.MODEL-ENGINEER.CO.UK

AN ADJUSTABLE PLATFORM Nicholas Farr’s solution to providing an accurate level surface.

Roman Dodecahedron So what are these mysterious objects really for y Michael illigan.

New mill user, what do I need to start. Looking for tips and advice, by obert owen attry.

SEND US YOUR WORKSHOP TIPS UK Readers can win Chester Machine Tools Vouchers.

June. 24

£5.85

Come and have a Chat!

A TOOL AND CUTTER GRINDER An easy and economical design from Stewart Hart.

INSIDE THIS PACKED

ISSUE:

 UNDERSTANDING MILLING SPEEDS AND FEEDS.  A WALL MOUNTED WORKSHOP CRANE.  MICROMILLING – AUTOMATING MOVEMENTS.  A SIMPLE LATHE BED STOP.  MAKING GEAR SPROCKETS.  EXTENDED STEM FOR DIAL TEST INDICATORS.  A MECCANO LANCASTER.  FREE HOBBING - SIMPLE GEAR CUTTING.  A VIBRATIONAL CLEANER.  PLUS ALL YOUR REGULAR FAVOURITES!

Get more out of your workshop with MEW

June 2024

Or search the forum for ‘getting the most’.

Find out more at: www.model-engineer.co.uk

As well as plenty of engineering and hobby related discussion, we are happy for forum members to use it to share advice and support.

Come and join us – it’s free to all readers!

I I

I

I

I

7

Cutter Grinder

The PottyEngineering Cutter Grinder Part 1 Stewart Hart describes a ‘quick and easy’ way to build a grinder to restore blunted milling cutters. The figures will appear across the three instalments of this short series.

The cutter grinder in action.

T

his project was slowly developing over a number of years, it was prompted by the realisation that I was slowly accumulating a collection of unserviceable blunt milling cutters; in fact I was rapidly approaching the point where I would have more blunt cutters than sharp. As part of my apprentice training, I’d spent a short time on the cutter grinding section where my father was the

June 2024

charge hand, I can well remember him teaching me how to sharpen drills by hand, a skill that I still have to this day, and of him passing on a good understanding of the cutter grinding process. I reasoned that I should be able sharpen my own cutters, if only I had a cutter grinder. Finance and lack of workshop space ruled out buying a second hand Clarkson or Cincinnati grinder, so I started looking around for other options:- I could build Professor

Chaddocks’ Quorn Tool and Cutter Grinder, or the grinder in Harold Hall’s excellent book Tool and Cutter Sharpening (workshop practice series No 38), then there’s the Stent Cutter Grinder, but all of these option would demand a fair bit of workshop time and effort, I wanted something that I could put together with the minimum of effort.

Then, by chance, the opportunity presented itself of buying an as new

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Axminster X/Y table.

Myford type vertical slide.

3

50mm riser block under vertical slide.

X/Y table at a very reasonable price, quite a few companies sell this type of table in a range of sizes, the idea being is that they can convert a pillar drill for co-ordinate drilling or even for use as a light mill drill, photo 1. I wasn’t too sure what I was going to do with the table at the time, but I had the inkling that it would help in my quest for a cutter grinder. It then languished in the back of my garage for a couple of years getting in the way of things whilst my collection of blunt cutters increased. Then for some unknown reason at a model engineering exhibition I spotted a Myford Vertical slide, photo 2. I’d known about vertical

10 www.model-engineer.co.uk

slides, but being lucky enough to have had a milling machine ever since I started model engineering I’d not given them must thought, but I had one of those eureka moments – why not use it with the X/Y table to make a cutter grinder? It should be possible to adapt any robust vertical slide for this purpose. When I got home a quick search of an internet auction site came up with a number of possibilities, I placed my bid on a likely candidate and came up trumps by winning a practically unused specimen at a good price. My quest then centred on the search for something to mount the parts on, I thought of using a kitchen

work top, but at one of my foraging trips to the scrap yard I dropped on a chunk of 1 ½” thick aluminium jig plate that was more or less the correct size and except for a few existing holes was virtually untouched.

Harold Hall’s use of a small readily available off hand grinder answered the question, as to what to use for a grinding head.

The X/Y table and vertical slide were mounted onto the jig plate using M8 bolts. Care was taken to get the orientation of the parts correct so that full advantage could be taken of the travel on the X/Y and vertical slide along with its swivelling action, this was mainly a simulation and trial and error processes to get the optimum positioning for the parts I was using.

I found it necessary to higher the vertical slide by 50mm by mounting it on a riser block, in order to get full advantage of its tilting action, photo 3. he o and grinder was mounted to the vertical slide using an aluminium adaptor plate and T nuts in the slide, it was at this point that I ran into a problem, most of the small commercially available grinders are mounted on a pyramid shaped plastic base which is fine for normal use when the grinder is mounted vertically on a bench, but to get full use from my set up I wanted to mount it horizontally this meant that the heavy overhanging electric motor moved the centre of gravity out, in this

Model Engineers’ Workshop

Cutter Grinder

Strong spring

Cam locking pins

End Mill Grinding Fixture G.A. For flute grinding, use with finger rest using index ring as a forward stop For grinding front cutting edges, lock index ring in front position index using pawl Design based on Philip Duclos’ floating spindle & Harold Hall’s end mill grinding fixture, plus some potty engineering by Stewart Hart

Figure 1

Part 1. ER32 Straight Shank Collet Holder

1 A

Section A-A

6 Ø5

Ø25

15.24

Ø36

Ø30

Ø44

1

Ø3

6

0.5

12 holes equally spaced

M3

Shank size: Ø25mm x 150mm long

A

20 30

Part 2. Index Ring Mat’l: Mild steel

Figure 2

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June 2024

11

4

Motor supported on ‘flexible’ plastic base.

position the plastic base was unable to rigidly support the motor, resulting in unacceptable levels of vibration, o o .

At this point I had nothing to lose by stripping the motor down to see what lay inside the plastic base. I found that it contained as well as the switch a mysterious black box, photo 5, but the good news was that the base was held in place by four M4 bolts screwed directly into the motor body that would be ideal for mounting it to the vertical slide, photo 6. But here I had come to the limits of my electrical competency, I found out that the black box was some sort of starter for the motor. I’d come too far to be beaten by a little bit of electrickery, so I asked around my model engineering club (South Cheshire) if there were any electricians who could help with my problem,

5

Mystery black box?

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www.model-engineer.co.uk

Model Engineers’ Workshop

Cutter Grinder 6

Motor fixing points.

7

Motor securely fixed to vertical slide.

June 2024

›

13

8

New switch wired up. sure enough there was more than one member with the necessary level of competency, willing to help, especially when it held the prospect of getting some milling cutters reground. So, the motor was dropped off at a friends’ workshop and within a couple of days I got a phone call to say that the job was done, my friend had rewired the motor up with a separate switch mounted on the base plate that now contained the mysterious black box (a motor start and run capacitor), allowing the motor to be rigidly fastened directly to the vertical slide via an adaptor plate, photos 7 and 8.

I now had all the elements of a cutter grinder, but I still needed some grinding fixtures. s I had more blunt end mills than anything else I decided that an end mill grinding fixture should be the first priority, when used on small home workshop milling machines it’s only the end face of the cutter that gets blunt, the rest of the cutter is usually pristine.

I wanted relatively simple minimal effort solution to this problem none of the published solutions had quite

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www.model-engineer.co.uk

9

Sharpening end mill with Stevenson ER32 index block. the level of simplicity I was looking for, then I hit on the idea of using the Stevenson ER32 indexing blocks I had bought some 12 months previously, these gave an immediate way of holding and indexing the cutter, all

that was required was a back stop and method of clamping the block to the work table. A simple jig plate with a back stop and a toggle clamp solved this problem, photo 9.

To be continued

Model Engineers’ Workshop

3D Beginners

3D Printing Workshop Ideas for Beginners Robert Walker is a relative newcomer to 3D printing, in this article he shares a host of practical ideas for printing workshop accessories.

1

2

Angle gauge for compound.

Angle gauge for compound.

I

turned sixty late last year and my three daughters gave me an Ender 3 v2 printer. er the initial setup and breaking in it has become a muchused tool.

As part of the learning curve, I drew simple parts in Freecad for printing

June 2024

but also made sure that they are something practical too.

I made two angle gauges for use in setting the angle of the compound slide on my lathe, photos 1 and 2. he first is 0 degrees for single point thread cutting. The second is

14.477 degrees the sine of which is .25. The reason for this is to achieve finer ad ustment of the micrometer dial on the compound slide. The smallest increment on the micrometer is .025mm so for each increment I remove .05 mm in diameter from the stock. ith the 14.4 degree off set the increment becomes .00 25 mm with .0125 of stock removal or one quarter of one thousandths of an inch. The rule of them is to multiply the amount of diameter reduction re uired in millimeters by 0 to give the number of increments to be dialed in. or example, 0.1 mm reduction is increments. 0.5 mm reduction is 40 increments. ›

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3

4

Micrometer lock for mill.

Sharpening jig for Diamond tool.

5

bloc

7

or so

aterials.

The locks for the micrometer dials on my mill were hex head bolts which required an Allen key to operate. The solution was to print a knob that the bolt can be screwed into and fastened with superglue, photo 3.

The clamping screw for the Diamond ool older sharpening ig also received a knob, this also negated the need for a washer to hold the tool, photo 4.

16 www.model-engineer.co.uk

Angle blocks.

Spring loaded parallel holder.

I o en need to hold round aluminium and brass stock in the vice, so I printed some V blocks that do not mark the stock, photo 5.

My budget is not huge and stretched in many directions so I do not yet own a set of angle blocks, so the solution is to print them as required, this also makes them sacrificial if needed. hey are as accurate as my Starrett No

C183 and Moore and Wright No 44 engineers’ protractors can measure., photo 6.

Like many I get frustrated when the vice is loosened, and the parallels fall over so I printed a spring-loaded holder. These can of course be made any size to suit, photo 7.

The locking mechanism for the compound table on the mill was a

Model Engineers’ Workshop

3D Beginners 8

Table lock for mill.

10

Guard for Dremel. toggle bolt arrangement consisting of a 3/8” rod with the end slotted and a tear drop shaped piece of sheet metal 25mm long pinned in to the slot forming a hinged handle. The sheet metal was hard on the fingers and would bend before the table was locked sufficiently. I printed a knob with a

June 2024

9

Drill and thread tool gauge.

11

Box for feeler gauges. recess for a bolt head that was a press fit that works uite well, photo 8.

A chunky hard to lose drill and thread cutting tool sharpening gauge was a simple pro ect, photo 9.

When operating a Dremel righthanded it can throw a fair bit of debris back at the user so made a guard for it

that can be rotated into any position, photo 10.

I have made several small boxes to protect thread gauges and the like including one for my feeler gauges, photo 11. nother pro ect is restoration of family photos, many from negatives.

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13

Negative frame.

14

Tool post grinder front.

The scanner has a frame to hold some negatives but not all sizes. I make them to suit the size required. To assist with correct location on the scanner platen I also made a H shaped spacer, photo 12.

Two short chuck keys with knobs instead of a bar assist with dialling in stock in a four aw chuck, photo 13.

In ovember 2021 M published an article by Adrian Rawson in which

18 www.model-engineer.co.uk

Small chuck keys for dialling in

15

Tool post grinder back. he described mounting a Dremel to make a tool post grinder for realigning his chuck aws. I thought I would have a go at it. Instead of mounting the remel I mounted the flexible drive hand piece by clamping it in a 3D printed box arrangement then bolting that to a piece of aluminium that was machined to fit in the tool holder. I also printed a former as suggested by

drian for the aws to clamp down on, an important part of the process. The run out on my 31 year old chuck was 0.5mm and a er grinding it is now 0.

0 mm, and some bell mouthing is gone too.Thank you very much Adrian, photos 14, 15 and 16.

For some reason I was holding a small engineers’ s uare and a inch steel ruler that had both metric and

Model Engineers’ Workshop

3D Beginners 1

Tool post grinder and chuck

17

Slide ruler attachment.

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19

Tee slot protector

Tee slot protector half removed

imperial graduations. I came the realize that the square could be used like a simple slide rule to convert metric to imperial and vice versa by reading across the ruler from one side to the

June 2024

other. I printed a small clip to fit on the ruler and slide up and down like the cursor on a slide rule, photo 17. ike everyone I find cleaning swarf out of T slots tedious, so I printed two

inserts for the slots on the saddle of the lathe. hey are angled to fit snugly against the tool post, both ends are angled so that they will fit in either slot., photos 18 and 19.

19

An Adjustable levelling Platform Nick Farr makes an accurate base for jewellery or pocket type digital scales.

I

have an 8068-series professional digital jewellery scale, which needs to be used on a flat and hori ontal surface for accurate weighing, this weighs up to 50g/0.001g, however it’s not always possible to find such a surface and if you do have one it may not be in the most convenient place, I therefore decided to make this adjustable platform, photo 1. And it can be used just about anywhere.

I made it to be able to fit my uratool 0 40 500g 0.01g digital weighing scale, and it will also accommodate my old PS-200B 200g/0.1g digital weighing scale. I haven’t included any drawings with dimensions, as these can be chosen for individual user’s needs, but it is 1 x 11 x 24mm, which was governed by the piece of 2mm thick aluminium sheet that I had available, and it weighs ust 2g.

1

Platform The platform is made by folding the aluminium sheet as can be seen in photo 2. It accommodates a piece of 20 x 20 x 1.5mm s uare aluminium box section at each end. olding the aluminium sheet in this way may present problems. I used my Vee block and a pressing tool in my fly press, but I folded the two returns first and then the top two as far as the pressing tool would allow, I then clamped a piece of 20mm box into the first folds and then clamped the sheet with the top face down onto the bench, with a piece of flat steel between the underside and the G-clamps, while using a spanner on the box section and gentle tapping with a mallet and then finally pressing each side home with my fly press, with the steel box section still clamped in place. A special pressing tool could of course be made to enable the second bends to be done completely with the Vee block, but I don’t have one

20 www.model-engineer.co.uk

The levelling platform. and couldn’t be fussed at the time to make one. Once the platform was folded, three holes to fit M stainless steel socket head countersunk bolts where drilled in each end, but the countersinking wasn’t done at this stage, and these were placed 10mm from the edge with the two outside holes roughly in line with the return fold’s inside edge, the return folds

being 20mm wide from outside to inside, but the two large holes that can be seen in these return folds, are not drilled at this stage.

If folding the platform is difficult to do with the return folds, another approach can be to have just two side folds on the platform, and then use two pieces of angle or two folded pieces for the return folds with the

Model Engineers’ Workshop