A prototype is a preliminary model of something. Projects that offer physical products need to show backers documentation of a working prototype. This gallery features photos, videos, and other visual documentation that will give backers a sense of what’s been accomplished so far and what’s left to do. Though the development process can vary for each project, these are the stages we typically see:
Proof of Concept
Explorations that test ideas and functionality.
Demonstrates the functionality of the final product, but looks different.
Looks like the final product, but is not functional.
Appearance and function match the final product, but is made with different manufacturing methods.
Appearance, function, and manufacturing methods match the final product.
Following on from the success of our previous kickstarter campaigns we have decide to launch our latest engine once again on Kickstarter. The engine will arrive in time for Christmas 2017. This is now our third hot air engine on Kickstarter! We call it the Nano Fin Engine. It is gamma type Stirling engine with a tube connecting the displacer cylinder to the power cylinder. The tube connection is as functional as it is visually appealing. We are well known for our rapid delivery of our kickstarter projects. Once again the engine is fully prototyped and tested. Our in-house CNC machines are ready to go!
Ready to run. Just add fuel
Engine comes assembled and is supplied with a burner and wick. The only things you will need is fuel and something to light the wick with. The engine is designed to run from methylated spirits (Denatured alcohol) which is widely available around the world. You just need to push the wick into the burner top, leaving it to protrude about 4mm (1/6 inch). The rest of the wick can remain curled up in the base of the burner. You then fill the burner with no more than ¾ full. Half full will last a long time running the engine. Put the lid of the burner on and place the burner into the base. It fits snuggly.
Starting the engine
Light the wick using a cigarette lighter, match or piezo electric starter. The flame may not be obviously visible at first due to the small size. Let the engine warm up. It won’t be able to start for 30 seconds to 1 minute. Once it has warmed up flick the flywheel. It will only run one way. If the burner is to the right and the flywheel to the left, the flywheel needs to rotate clockwise. You may need to flick the flywheel a few times for it to start. The engine will start slowly but as the engines parts warm up it will roar into life.
How a Stirling Engine works
Stirling engines convert a temperature difference into motion. There is a hot side and a cold side to the engine. Provided there is a large enough temperature difference the engine will run. Stirling engines work by cyclically heating and cooling the air inside the main chamber. As the air heats up it expands, and as it cools down it contracts. This expansion and contraction drives a small piston which in turn drives the flywheel. The clever thing about Stirling engines is that the mechanism for cycling the heating and cooling of the air is built into the engine in the form of the displacer, which is driven by the flywheel and moves the air from the warm side to the cool side and back again over and over.
History of Stirling engines
The Stirling engine is named after its inventor, Rev. Robert Stirling, who patented his idea for a closed cycle hot air engine in 1816. He also invented the improvement known as an economiser which is known today as a regenerator. From around 1860 to around 1930 Stirling engines were produced in significant numbers. They were typically used for pumping water, as they had the benefit of being simple to use and only needing a fire; unlike a steam engine which needed water to begin with. By the 1930’s Stirling engines had been mostly replaced by piped water, combustion engines and increasingly by mains electric motors. Importantly, Philips had been quietly working on a Stirling engine generator since the late 1930s mainly as a means to recharge radio sets as mains electricity still wasn’t ubiquitous. By 1951 Philips was demonstrating the MP1002CA generator. Sadly it was not commercially viable for numerous reasons including the introduction of transistors, better batteries and the spread of mains electricity. However all modern commercial Stirling engines can trace their ancestry back to these engines.
Don't worry you don't get a kiss from a bearded engineer! Due to the time restraints we have just decided to keep the rewards simple. KISS is an acronym for (Keep It Simple, Stupid!). The rewards consist of one engine, no customisation and no add-ons. The only differences are discounts for the early bird and early worm backers. Plus an option for delivery after Christmas.
If you back us early with an early worm or early bird reward you can get the engine at a reduced cost. Equally if you don't mind waiting until after Christmas there is a different reward which will save you some money.
The design of the Nano Fin engine was started in early 2017. The engine was fully tested in CAD before any parts were made. By the summer, early prototypes where being tested. There was a short delay in development while we moved our workshop to new premises. In recent months the final production prototypes were finished and the engines were thoroughly tested. Once the kickstarter project is live we will watch the pledges and as soon as we break the kickstarter target we will start production of the engine. In other words we will start while the kickstarter project is still live. Unconventional I know, but we have done enough kickstarter projects to be confident to do this. By the time the project has ended and we have collected payment, all the engines promised for Christmas will have been made. Dispatch will be the second week of December by a fast courier.
Production of the post-Christmas engines will start in January. Production in January is always quite slow. We would aim to send out the remaining engines in February.
In-house CNC workshop fast turnaround times
Some parts have already been made!
Yes some parts have actually already been made. The engine shares a few common parts with its sister engines (previous kickstarter projects). Namely the base plate, foot, flywheel and things like the glass and bearings.
Quick delivery by FedEx or DPD
We recognise we will need to get the Christmas rewards to you quickly. So for this kickstarter project we will use quick couriers. For International orders this will be FedEx. For UK orders this will be DPD. We reserve the right to use a different courier when the said courier does not offer a service to that country or courier has known issues with that country (e.g. Russia)
Why we need your help
All our engines take months of designing, trying out various mechanical linkages and parts, and then building prototypes to perfect. Just like previous development of engines, it takes numerous design iterations to get to our final working prototype. We could start producing a small batch tomorrow and with a few weeks have a small number of engines built, but small batch runs are inherently expensive. Why is a small batch run expensive? All the parts will be machined on our own lathes and milling machines at our workshop. But the CNC machines first need to be programmed and set to run a batch of parts; usually taking hours for each component. CNC machines are not cheap, and it is industry standard to bill the set up time across the batch of parts. e.g. If the setup cost for part is £150 and you make 10 parts, then those parts would cost £15 + the raw material + the time to machine. But if 1000 parts were made the cost would drop to £0.15 per part + the raw material + the time to machine.
Tooling cost is a large cost. We need to design and machine tooling so our CNC machines can hold the raw material securely and to allow for quick, efficient machining. Designing the tooling carefully and making many parts at one time optimises production, meaning the machine can produce more parts faster. This reduces costs considerably. Making a good size batch also means we can save on material cost by buying in bulk. It won’t be a huge saving but it all helps. By increasing the batch size and optimizing tooling for more efficient machining we can attain in excess of a 60% reduction in production costs. So in summary we need your help to make tooling for all the components, and to spend the time to programme the CNC machines to make the components in the most efficient way.
With your help we can make the project a success!
The Kontax Guarantee
We ABSOLUTELY GUARANTEE that every engine we sell will run as advertised. If your engine struggles to run as advertised then we ABSOLUTELY GUARANTEE that we will offer all possible help to you until it does. All Nano fin engines will be individually packed in supportive packing and rigid cardboard tubes, which ensures safe arrival of your engine. Each Nano Fin engine will be machined and assembled in our workshop and fully tested before despatch.
Designed and Engineered in England
All of the parts for this engine are manufactured by us in our modern CNC equipped workshop located in Maidenhead, England. This allows us to maintain very high standards, and gives us absolute control over the precision parts used in our engines. Kontax Engineering Ltd was formed in England in 1964. We were the first to sell a Low Temperature Differential (LTD) Stirling engine in 2001 and we have continued to develop new and exciting engines ever since. We pride ourselves on producing stunning engines using excellent engineering. The 16 Years of Stirling engine experience is shown in our engines.
Risks and challenges
Kontax Engineering Ltd was founded in 1964 and we have been making and selling Stirling engines since 2001. We are known for producing quality engines that people adore. Customers often come back to buy another engine for themselves or a loved one. We have been running e-commerce websites since 1999 and we ship worldwide on a daily basis.
Our new engine has been designed using the latest CAD software, prototyped and tested thoroughly.
We have backed many kickstarter projects ourselves and seen some falter. That’s why we have chosen to develop the project further before bringing it to kickstarter. We are ready to start production. The difficult stuff has already been achieved. Furthermore this is our 3rd in-house and 4th overall Kickstarter project we have had involvement with.
For this project we have decide to limit the number of engines we can make in time for Christmas. The rewards are broken into ones for before Christmas and after. We already have all the raw material ready for the ones before Christmas. This removes the risk of having an unexpectedly large number of backers.
For this kickstarter project there are 3 small risks:
UNEXPECTED PRODUCTION DELAYS
This could be something like a machine breaking down or staff illness. We now have 9 staff (part/full time) and 6 CNC machines. I think this risk is small but it is worth mentioning.
We have been involved in e-commerce for many years. We use good couriers. However sometimes, weather, strikes, terrorism etc can cause delays. In previous Christmases we have seen small delays. Again a small risk but worth listing.
It is possible there will be delays processing payments or delays with kickstarter themselves. Again a very small risk but nonetheless a risk.
Just for openness, transparency and reassurance, our workshop is at Kontax Engineering Ltd, Unit 6 Maidenhead Enterprise Centre, Cordwallis Street, Maidenhead, Berkshire, SL6 7BE, England. Company number is 831774. VAT Number is 302119025. The company owner, 100% shareholder and director is Glenn Turner. The company website is: http://www.stirlingengine.co.uk
We have done TWO other kickstarter projects. Search under "Nano Cannon Stirling Engine" and also “Nano Disc Manson Hot Air Engine - by Kontax Engineering”. You can read the positive feedback in the comments section.