A reader’s interest in Elmer’s #3 Open Column engine prompted me to check through my postings on this engine and discovered that I had not added the final chapter and had left readers in the air with a non running project.

I eventually resolved the problem by making a further chassis to slightly tighter tolerances, which reduced the amount of air escaping from the wrong places - i.e. along the crankshaft. This is a lovely little engine which now runs well but it does require more care in construction than say, Elmer’s ‘Wobbler’.

The ever versatile iPod can be used as an accurate and practical clinometer with the help of a neat application available from the iTunes store..

Prompted by one of my Swiss readers I thought owners of either iPod Touch or iPhone might be interested in this little app available for the modest sum of £0.59.  It is extremely accurate and highly sensitive enabling accurate angling of workpiece prior to machining.

This handy application has a number of very attractive features aiding practicality and accuracy of use.

You will find further information at plaincode

click on image for larger view

My eZee Liv electric bike which provides me with almost effortless cycling and gives me an enjoyable break from the many hours couped up in my workshop

I think most will agree that model engineering is an ideal pastime for the mechanically minded during their retirement years.

To my mind though there is a real danger that you can become so absorbed in your hobby that you spend all your available time hidden away in the workshop. In my case my workshop is the domestic garage with hardly any natural light from which I ocassionally emerge blinking like a mole.

During the warmer days (remember those ?) I started to give myself  ‘days off’ so I could get outside and enjoy a break from whatever project was dominating my waking and sometimes, sleeping, hours.

I reluctantly packed in my passion for motorcycling a few years ago and in its place discovered the world of electric bikes.

Electric bikes are power assisted cycles using low voltage motors normally fitted unobstrusively into the front or rear hub and powered by specially developed high capacity rechargeable batteries. This takes much of the hard work out of pedal cycling, increasing enjoyment yet retaining the freedom of a conventional bike.  A good electric bike takes much of  the pain out of climbing hills and provided you put in a reasonable amount of effort you can climb hills of 1 in 10.

Further good news is that there are very few restrictions. Maximum allowable speed is 15 mph under British Law and riders must be at least 14 years old.  Apart from that you are as free as a conventional cyclist. You can legally use designated cycle lanes and the increasing network of cycle tracks that are sprouting up around the country.  I often pop into my local market town of Wetherby, a round trip of about 10 miles, most of which is along an old converted railway track. I have even been known to travel as far as York and back a round trip of 30 plus miles and no parking problems when I get there.

The gentle cycling is good exercise and the fresh air and sunshine is a good antidote to those prolonged sessions in the workshops.

If anyone is interested in learning more I would suggest you take a look at OnBike - electric bike specialists. An excellent range of the latest bikes backed up by an enthusiastic team of e-bike specialists.

Here’s how OnBike summarise the benefits of e-biking…….

Economy

Electric bicycles are incredibly frugal compared with motorbikes and cars.

On average, they cost less than 2p to recharge which is the equivalent of 1000mpg (20 times the mpg of a small car)

They are treated just like ordinary bicycles for legislative purposes so there’s no need to worry about Log Books, MOT, Road Tax, Insurance etc.

Most of the working non electrical parts are standard cycle parts so day to day servicing like tire or brake replacement will seem very cheap for people used to paying for car repairs.

Health and Hills

It is said that a conventional bike will keep you fitter. That, of course, depends how much, if at all, it is being used. Because riding an electric bike is such a pleasure even in hilly country, or into the wind, their owners tend to ride them much more often than conventional bikes. The motor provides up to half the effort, but regular use means more exercise for the rider.

If you want some strenuous exercise you can always switch the motor to a lower assistance ratio or turn it off completely.

Fun

They are incredibly good fun. If you have never ridden one before you will find you get all the pleasure and fresh air of a bicycle, without the hard work, and all the excitement of a moped or a scooter, without the fumes, mechanical complexity, noise and cost.

First time riders invariably come back with a big smile on their face and many have commented “It’s like riding a normal bike only with a big friendly hand giving you a push on the difficult bits”.

Perspiration may not be a serious issue when out for a leisurely ride, but it’s more important when cycling to work. An electric bike eliminates the problem and allows riders to wear their normal clothing and really enjoy the journey.

If you are or have been a regular cyclist but are beginning to find it a bit too much like hard work then you really must try an electric bike. Suddenly those trips that seemed a bit too long will have halved in distance and those hills that were a bit too steep will have miraculously flattened.

Green

Using an electric bike is the best way there is to break the car habit. The average car journey in Britain is 5 to 8 miles and every day people in Britain make millions of small journeys to work or the shops and back that could easily be non-polluting bike rides - during rush-hour, a bike is twice as fast as a car - great if you hate jams!

An electric bike is completely emission free can be made genuinely sustainable by purchasing electricity from a ‘green’ supplier, or generating it via a roof-mounted windmill or solar panel. This will enable the vehicles’ fossil fuel consumption to be zero.

OnBike

A Rocking Good Engine from Malc Tompkins.

There have been a number of creative interpretations on the Rocking Engine. When regular site visitor Malcolm Tompkins saw my art decco interpretation it inspired him to have a go. Malc has doubled up all dimensions to produce an impressive sized engine which not only looks good but sounds wonderful too.

Like many, including me, Malc was rather sceptical about the simple but unusual method of running. Air is continuously fed into the cylinder head forcing the piston down. On its travel down the bore the offset crank shaft twists the combined piston and rod out of position allowing the air to ‘exhaust’ - momentum pushes the piston back up the cylinder where the cycle is repeated. Not too good a description perhaps but it’s the best I can do. Just follow the plans and I promise you it will work !

This is an excellent project and within the scope of the newcomer to model engineering. Particularly clear and concise plans are available for download from http://www.john-tom.com/html/SteamPlans3.html (you’ll need to scroll down the page to find it).

If anyone else has produced a restyled version of this cracking little engine maybe they would like to send a pic or two or even a short video for inclusion on this site. You can contact me at john@start-model-engineering.co.uk

Here is an excellent model engineering website from Rob Roll of Rochester, NY in the States that is well worth a visit. There is much information that will be of great interest to enthusiasts both newbies and the more advanced.

One of the first items to catch my eye were details of a low cost easy to make DRO (digital read out) for the cross slide of the mini-lathe. This must be a great boon when turning stock down to a precise diameter - how many times have I taken a cut too far !

There are some real gems amongst the free engine plans including Bogstandard’s “Paddleduck” Engine. Whether you build the “Paddleduck” or not, load up your printer with fresh ink cartridges and a ream of paper and print out the 113 page tutorial. I had my copy fitted with covers and spiral bound at my local stationers. It is crammed full of really helpful machining techniques with supporting photographs and Bog’s inimitable C-o-C sketches.

Anyway take a look at   Machinistblog.com - I don’t think you will be disappointed .

All in all a positive treasure trove of inspiration, plans and ideas for the model engineering enthusiast.

Create your own shape and choose the colour for your LED and make one or two for your friends

There are two famous people in Wales and they both play billiards. The first is a chap called Terry something-or-other and he is renowned for his ability to send even the most ardent insomniac into a deep and blissful sleep on a Sunday afternoon.

The other chap is called Ralph. He’s also known as ‘Divided Head’ - I am not too sure why but I suspect it may have something to do with an incident involving an up and over garage door.

Recently Ralph caused outrage amongst certain old school model engineers when he revealed his lathe mounted mop polisher.

Any road up Ralph has unselfishly agreed to disclose his method of making little brass torches. I am ignoring the fact that my local petrol station is currently offering an impressive looking multi bulb LED torch for a mere £2.50. Ralph’s torches are truly little gems and make lovely gifts for family and friends. Not only that but they are fun to make and provide an opportunity to hone your turning skills and demonstrate your creative talents.

So, without further ado lets get the boys on the baize.

Ralph has produced this excellent series of 4 videos with step by step build notes to guide you through the construction but before you sit back and enjoy here is a cut away sketch showing the various components.

A cut away sketch showing the components and assembly

Video 1

1/ Cut length of 1/2″ hex or 9/16″ round brass bar to be finished to 25mm length. Round bar at 1/2″ will show thread cut on outside and can be hard to get rid of. That’s if it doesn’t tear through the side ! 9/16″ bar allows a quick lateral turning with the cap blank screwed tight so it mates perfectly.(before the cap is cut and shaped!) Hex shows thread slightly but a light draw filing or lapping sorts this.

2/Face off both ends.
3/Centre drill.
4/Using 5mm drill, drill through bar.(assuming you have purchased 5mm blue, red, white or green LED?… else a 3mm or 8mm led could be used, depending on power requirements?)

5/Using 10.5mm drill (prepared for brass if possible.) make a 16mm deep hole for the innards of the torch. Tap the body with a M12×1.5 thread (I always bottom the tap out.)
Cut a recess for the O ring (see video/Crap-O-cad) Just removing the thread should give sufficient space for the main O ring to sit. ( Run the tap back through to chase/clean up thread. remove thread burrs.)

6/ Remove the main body and place to one side. take another length of bar at least long enough to get a parting tool into once it has been cross drilled….see video1. Turn down to 12mm dia and at least 9mm length.

7/Cut M12×1.5 thread onto remaining turned section.

8/Using parting tool cut recess into turned section at base. (approx 1-1.5mm deep depending on the ‘O’ ring you have selected for the seal)

(you could do parts 7 and 8 in reverse order … It wouldn’t alter the outcome)

9/Test fit main body. If a hex bar is used and you want it to line up perfectly then a bit of fine skimming work on the main body length will probably be needed (unless you’re lucky)
(The pattern is usually a little off when fully tight, a bit of draw filing or flatting of each of the sides once the torch is completed will true up the pattern enough to fool most eyes.
If your not too fussed… Like in the video, then leave it!
The torch when off will be where you set it… lined up if you want it that way, and when it’s on it’ll be where ever it is…. Up to you what you want it to finish like.

Video 2

10/ Cut a length of thin plastic (packaging like you get paint brushes/batteries etc in is good for this, thin but stiff when cut into a strip. Thickness of plastic must be assessed as slight thickness variations could prevent the batteries from being easily inserted and removed !
I pull the plastic hard over a thin round bar, causing it to curve and hold that shape. Trim the plastic to length and depth.
Depth of plastic shown is in drawing. It is the height of the two cells stacked. It has to prevent the outer body of the battery/cells from touching the inner of the torch body. Insert the plastic when ready, check for overlap or not enough coverage.
Trim small slices until you get it just touching when fitted.

11/ Check LED polarity, easy way, touch the leads onto the poles of one of the cells (if you’re using the 3V ones specified) alternatively you could use a meter or search for data on the web to identify the Cathode and Anode.

12/ Cut a disc of plastic rod 1.5-2mm thick 10.3mm dia and drill a 1mm hole 2mm off centre for the LED negative leg. The negative leg is then passed through the hole and cut to allow 3-4mm to protrude. This is then folded across the centre of the disc. (see video)

13/ Bend the positive leg flat horizontally to the opposite side of the disc. Bend the leg up around the edge of the disc (keeping it tight to the disc) Cut the leg to length, level with the top of the disc (any higher and it might short circuit the cells!…. See video)

14/ Insert the completed LED assembly into the main body of the torch and push the led home. This may need a bit of a shove…. Try not to damage the LED or it’s legs!

15/Insert the insulator strip.

16/ Insert 2x cr927 lithium cell battery’s negative end first and keeping the torch pointing downwards screw the threaded section into the body till the LED illuminates..

17/ The LED will illuminate before the cap is all the way home. Check with a vernier or similar, the gap left between the cap and body sections.
(This is all done because there are always variables, from slightly less or greater depths when drilling to LED legs and exact insulator disc depths….. This is a very adjustable design)

Video 3
18/ Re-chuck the tail cap blank and remove all but 0.2mm of the length measured. Turn down the threaded section to allow a 8mm dia and 1-2mm deep stub to be formed.

19/ At his point remove the work from the lathe and fit it as per 16 and 17, remove just enough for the light to turn on as the cap and body edges meet. Remove with VERY fine cuts (even emery) the amount needed to get the light to turn on just as the cap and body edges meet.

20/ Dependant on your O ring size make the recess Using a parting tool or 1-1.5mm thick tool (specially made for another job?). Cut a recess into the face of the cap (see video) wide enough to take your O ring and deep enough to allow it to stand a hairs width over the centre stub.

21/Once satisfied that the O ring is to the correct height. Glue it into position, superglue is ideal.

22/Cross drill a hole through the bar, approx 8mm from the mating face of the tail cap (thread end) this is for the split ring. (I use 2.5mm see video/drawing)

23/Part off the cap, (or hack saw) allowing for the correct length to be achieved when making the eye on the cap (I allow 4mm over the top of the cross drilled hole).

24/Screw the tail cap on to the main body and using the body as an arbour to hold the cap in the lathe. Turn it down to a shape of your liking. (See video, freehand shaping is your own and original every time !) Use a small bar in the split ring hole to undo it after this process, it will have tightened.

Video 4
25/ Turn the torch around and turn your desired concave dish design (being careful not to hit the led!… you could remove all the inners if you wish) You could have the LED protruding? Just be careful not to remove so much material that the LED sticks out and could become scuffed easily, a little scratching effects the light output greatly!
I styled some with stepped cuts and rings. But I am sure your own design desires will lead you to a finish of your choice.

26/ At this point I draw file or flat the hex body. (see video) I gave a nice turned finish on the round ones and polished some of them to remove imperfections.

27/ Add a split ring, brass coated ones can be purchased very cheaply from a key cutters/hardware store. Takes some doing not to scratch the cap when fitting the split rings though! (I use a round pointed barto open the ring to 4mm and then to hold the ring open as I pass the ring through the cap. Then transfer it to the end as it comes around so that it doesn’t scratch as it snaps shut.) Once the ring is on it’s pretty easy to turn on and off…. Might require a smear of petroleum jelly?

Little cheats….

If the grip between the body and main O ring on the cap is weak when turned off ( Off - should be no more than one flat, or on the round torches less than a ¼ turn anti clockwise) and it needs to be tighter to prevent the parts from separating.
Then you can cheat with a very narrow strip of black insulation tape under the main O ring.
It must be exact length. An overlap will alter the depth considerably.
They MUST be slightly stiff to turn, as this stops you losing the body of the torch off the cap as it rattles around on your keys or in your pocket.

If you take too much off the tail cap and it doesn’t reach the cells.(when screwed in to make the ON contact.)
You can re-make the LED disc/insulator a bit thicker…. This will raise the LED leg (be careful not to damage the legs removing and re-bending them) and raise the batteries…. Be sure to check that the insulator sleeve depth, it should be fine. But check it all the same.
(you can make the discs in small increments till you get one that’s right if need be)

Parts list:

Brass bar - 13mm or ½” hexagonal for the torch shown in the video or 14mm or 9 1/6″ round. Minimum length required 50mm (25mm body and then the cap from the off cut….. I try to use as longer bar as possible to make the cap on though for safety and ease of machining)

LEDs available in a range of colours and 3,5 and 8mm sizes

LED - 5mm very high brightness type …. 32000mcd for white….(clear focused casing)
There are many, many types of LED, colours and intensities…. From past experience always go for clear narrow focus, 15degrees or there abouts works well for most applications and as for the mcd rating…. The higher the brighter is the way it’s supposed to go But it’s a mine field if you go looking for the best for the buck!
You shouldn’t pay more than a couple of quid for 5-10 posted from China/Hong Kong via e- blag….. I certainly wouldn’t get ‘em from the high street retailers here in the UK…. Rip off!
Rubber O ring - to fit collar of cap 10mm internal 1.2mm dia material (you can alter dimensions of cut to suit your O ring.

Rubber O ring - to fit contact point of cap 3-4mm internal 1.2mm dia material
(Again O rings can be found to fit your cuts and cuts made to fit your O rings )

Nylon or equivalent impact resistant plastic bar @10.3mm min’ dia’.

Thin stiff plastic strip to be cut to size (depth of 2 cells and enough length to seal outer wall of torch from cells.)

½” Brass coloured split ring

Apart from some cosmetic detail Opus P. is now completed but steadfastly refuses to show any signs of life. Examinations will continue but my suspicions lie with the porting arrangements.

I am concious of the fact that a number of people have been following the build of Stan Bray’s Opus Proximum and that they may be wondering why this thread has ground to a halt.

The truth of the matter is that so far, despite, my best efforts, Opus refuses to run. Not only will it not run there is absolutely no sign of life. My suspicions focus on the inlet and exit porting arrangements and I need to carry out some visual comparison tests against similar valve arrangements on one or two of my Elmer engines. Even before I attempted to put some air through my Opus P. the opening and closing of ports didn’t seem to be quite right. When air was connected up it appeared to run straight through and out of the exhaust regardless of the stage in the cycle. There is a slight change in note as the valve moves in the chest but there is clearly something basic that is not right.

As readers will know I did discover a number of anomalies with the plans for Opus P. and I am beginning to wonder if this string of errors includes the critical porting arrangement.
It may be a few days before I am able to continue further examination if meanwhile any readers have any thoughts or ideas I would be very interested to hear from you. Indeed I would be interested to hear from anyone building the Opus P. and to hear of their experiences.

This is a simple single acting engine with an unusual inlet/exhaust arrangement. It runs beautifully on less than 5 p.s.i - in fact I can spin the engine by blowing down the air inlet pipe.

To be honest I was baffled as to how the engine worked in terms of controlling air input and exhaust.

Fortunately Bogs was on hand to enlighten me and I quote

“The unusual valve arrangement is done by the rigid thin piston and the offset from centre crank. The air is fed continually down the head, so when the piston is at tdc the piston lays in a normal position and is pushed out. The flywheel then takes over and turns the offset crank. Because the crank is off centre, the piston is tilted forwards at the top and back at the bottom, so allowing the air to flow past the top and bottom of the piston for the flywheel returned stroke. Once the piston reaches the end of its travel, it is then flat again, and so the outstroke takes place.”

The plans for this engine are available from John-Tom’s treasure chest of steam engine plans at http://www.john-tom.com/MyPlans/SteamPlans3/RockingSteamEngine/ROCKING%20STEAM%20ENGINEs.pdf

At the time of building this very popular engine a number of model engineers had already made their own design variation and I decided to follow suit with an ‘art deco’ look. Whilst it is clearly important to retain the key dimensions in terms of cylinder bore, piston size, crank throw etc there is no reason why you can’t get all creative and have some fun with the general cosmetics. Which is what I decided to do. So here we go with the build.

Next on the ‘to do’ list was drilling and tapping the back of the cylinder for attachment to the engine frame taking care not to drill through into the cylinder bore - 4mm seemed about right. Where possible I use a guide block to ensure my tap runs square to the hole. You can also replace your drill bit after preparing the hole to be tapped with the appropriate tap and turn the chuck a few turns by hand to get the thread started and running square. This can then be transferred to the vice for finishing off.

The next stage I am afraid didn’t get covered photographically. However, the piston was turned from aluminium, cross drilled for the gudgeon pin (or wrist pin as it is called across the pond). The con rod was turned up on the lathe and again transferred to the mill for putting the flats on both small and big ends. The con rod needs to be turned as narrow as reasonable to clear the base of the cylinder.

The crank shaft was machined from stainless rod to produce the flats which cleverly act as inlet and outlet ports. Clearly to be effective your crankshaft needs to be a very snug fit in the bearing to avoid air loss. I am sure it is not aproved engineering practice but as you will see from my picture the crankshaft was overhung from the vice for milling the flats. Very light cuts were taken and a satisfactory result achieved.

Care needs to be taken when drilling the exhaust outlet along the length of the crankshaft - slowly does it with plenty of backing off and cleaning and lubing of the fine drill bit. The crank was ‘loctited’ into position making sure it was set square to the inlet and outlet flats on the crankshaft - refer to your plan.

Now I would like to tell you that I assembled all the components, connected up the air and off she went. Well I found that I couldn’t quite get a full rotation due to the top of the piston making contact when approaching TDC. I used a milling cutter by hand to clean up and ‘bottom out’ the head of the cylinder. The engine now rotated by hand - a spot of oil added to cylinder bore and bearing surfaces, air connected and off she went and after just two or three minutes she was running a treat on around 5 p.s.i.

Elmers Standby

I used a liberal amount of cutting oil applied by small paint brush to ease the cutting process. I have found that (fine cut) emery backed sponges are ideal for cleaning up workpieces in the lathe. Never be tempted to use a rag as this can so easily wrap itself around the chuck and drag your fingers in before you realise what is happening. Safer to use paper towels but I find the emery sponge ideal.

After centre drilling I ran a 2mm pilot hole in the end of the bar before carefully selecting, in this case, a 3.8mm drill to match the actual diameter of my 4mm stainless shaft that I intend to use for the crankshaft. Do check drill and shaft sizes carefully with your vernier to ensure that you finish up with a nice snug fit. I normally drill slightly undersize as the rotation of the drill does produce a slightly larger hole than you might expect.

Although this next stage could have been completed with hand tools (junior hacksaw and files) it is easier to use the mill. Each crank was set up in the vice using a small length of shaft thro the larger hole and an appropriate drill bit for the smaller hole. Use of the ‘X’ and ‘Z’ readouts gave me control of the cutting area. The backstop allowed me to turn the crank ‘upside down’ for identical machining on the other side. It also allowed me to machine the second crank to the same dimensions without the nead to reset machining limits.

Screws with shoulders to provide a bearing surface for the connecting rod were turned up in the lathe and a die held in the tailstock to provide a 3mm thread. A quick polish on the buffing machine finished this stage of the build.

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