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rickharris

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35Instructables1,693,226Views10,969CommentsUK Lincolnshire
Retired technology teacher - 2 kids, I have an Hons deg in Design and Technology - 28 years as Computer systems engineer Trained as Electronics engineer in the Royal Air Force

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  • rickharris commented on Cheesey125's forum topic Speaker purchasing

    https://www.youtube.com/watch?v=zdkyGDqU7xAmake them for less than $30

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  • I gather you want to build a solenoid engine. Yes Current is Voltage / resistance. Usually a solenoid will draw a fairly large current because this gives a big magnetic field and so more force.I guess your really asking how may turns and what gauge wire to use to make your solenoids - easy way is to see what someone else has done.https://www.youtube.com/watch?v=gncDJAV_NhgOtherwise you will have to look up the current your preferred/available wire gauge will carry and then work out how many turns ( and so resistance of the coil) for the current you want it to draw. Starting with what someone else has done is a good place to be.

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  • To build an MP3 player from scratch is a big project (if that is what you want to do)There are, however a lot of ready made and cheap choices on Ebay and Alli express. https://www.ebay.co.uk/itm/HiFi-Bluetooth-Power-Amplifier-Mini-Bass-Audio-Stereo-Amp-USB-SD-TF-FM-Mic-Input/193245888684?hash=item2cfe5a40ac:g:ztsAAOSwfHVbRLT-is an example from ebay Uk for just £8 bout $10 Blue tooth and USB input.Search for Audio amp USB input.

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  • Don't buy - Can't smoke/vape - Self regulating. If you don't have the willpower to stop buying your likely to get round any timing device.

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  • 1. Always add a little oil to butter to prevent it burning2. This takes time so low heat. 3. you can add a little water to help things along4. I add a little brown sugar to assist process.https://www.simplyrecipes.com/recipes/how_to_caramelize_onions/

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  • This is a VERY complex projecthttps://www.maximintegrated.com/en/products/power/MAX769.htmlgives some details.If you can work out how to programme a raspberry pi this can interface to a mobile system and send SMS Check google for details.

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  • L239 has a max current limit of 1 amp. this isn't much for a vacuum cleaner you need more power. (unless this is very small)The L239 is driven by a microprocessor (normally) https://www.instructables.com/id/Using-Motors-With-L293D-IC/shows how.Google is your friend here.

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  • rickharris commented on schockmade's forum topic 3D Print Masks

    Be cautious. PLA is porous as produced off the printer.Any type of filter is of limited use as virus particles ar nano sized.Most of these printed filters do not form fit the face and so leave gaps. Wearing a faulty filter could/will give a false sense of security - without one you take more care.With a virus it isn't true to say anything is better than nothing, you do not need many virus particles to get through to infect you - and others.Masks are of most use to put on sick people to stop them coughing or sneezing infected water droplets into the air. Surgeons wear masks so they don't infect the patient.Covid19 isn't spread through airborne means it spreads by touch and contact.Wash hand regularly avoid others. Deny the virus a pathway into the community. Make a fire break by self isola…

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    Be cautious. PLA is porous as produced off the printer.Any type of filter is of limited use as virus particles ar nano sized.Most of these printed filters do not form fit the face and so leave gaps. Wearing a faulty filter could/will give a false sense of security - without one you take more care.With a virus it isn't true to say anything is better than nothing, you do not need many virus particles to get through to infect you - and others.Masks are of most use to put on sick people to stop them coughing or sneezing infected water droplets into the air. Surgeons wear masks so they don't infect the patient.Covid19 isn't spread through airborne means it spreads by touch and contact.Wash hand regularly avoid others. Deny the virus a pathway into the community. Make a fire break by self isolating for as long as it takes. We will win this by:1. Deny the virus a transmission route - self isolate2. Developing a vaccine 3. Everyone getting it and becoming immune. (the last isn't an option because many billions would die.) 4. Keeping as many people out of hospital as possible so there is room for the seriously ill.

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  • Essentially the WWW is the biggest library in the world However about half the "book" have been written by lunatics. People need to be aware. There is NOTHING for FREE.

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  • Micro controllers are essentially linear devices. ie 1 command after another. KLay out your programming needs as a flow chart you will then see how the flow works and can allocate the relevent parts of the programme to the right place.

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  • rickharris commented on M4rtin-iow's forum topic Hi Guys

    weigh the vesel then you will know how much water is in it.

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  • https://www.google.com/search?q=555+timer+ccts&sxsrf=ALeKk006E_-UfsWCi5Ss-eILHHAx44eQyg:1584474076434&source=lnms&tbm=isch&sa=X&ved=2ahUKEwiJ8ezzoaLoAhVFThUIHbGCCF0Q_AUoAnoECA0QBA&biw=1920&bih=937You going to find something here to help you.

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  • There are different grades of silver solder that melt at lower or higher temperatures.Usually if you can't get the silver to melt its a flux problemWhen I solder delicate things I trap most of the ring in a heat sink, a vice or pliers leave the gap showing and the solder the bit I can see.A very small flame o the torch also helps keep the heat where you want it rather than heating up the entire ring.

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  • rickharris commented on BeatriceR7's forum topic Hexagonal table

    Advantages? Well its easier to make than a round table Cut in half and put up against the wall as what we in the UK call a consol table.

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  • You could substitute the Meths for Vodka I guess 40% proof should do it. To be honest soap works better as it disrupts the fatty layer on the outside of the Virus. Even a soapy cloth would work. You have to wash the whole hand though, in between the fingers front and back.

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  • https://www.electroschematics.com/door-opening-alarm-alert/here is a simple magnetic alarm. For the RFID part your going to need to delve into microcontroller programming. I would keep it simple. A key or magnetic bypass is a lot easier.

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  • Mmm, a ventilator is more complex. the pressure is critical as you can easily damage the lungs.Generally once you push a tube down someones throat they try to push it back out and cough.To prevent this the patient is paralyzed with drugs.Because they are paralyzed which is somewhat scary they are also deeply sedated. As a machine they are very costly and complex although at their heart they are a simple bellows pushing and sucking air.I don't think this is a DIY project for the average handy man. Although I have no doubt that given a set of plans the likes of Old Tony etc could do it.To be honest the best thing anyone can do is keep themselves out of Hospital so the beds and equipment are available for those who fall ill and really need them.A significant number of patients world wide hav…

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    Mmm, a ventilator is more complex. the pressure is critical as you can easily damage the lungs.Generally once you push a tube down someones throat they try to push it back out and cough.To prevent this the patient is paralyzed with drugs.Because they are paralyzed which is somewhat scary they are also deeply sedated. As a machine they are very costly and complex although at their heart they are a simple bellows pushing and sucking air.I don't think this is a DIY project for the average handy man. Although I have no doubt that given a set of plans the likes of Old Tony etc could do it.To be honest the best thing anyone can do is keep themselves out of Hospital so the beds and equipment are available for those who fall ill and really need them.A significant number of patients world wide have died because of heart failure associated with viral Pneumonia. Sadly another DIY idea often used is to design and cheap protective mask people can wear. A virus particle (they are not alive) is on the Nano meter scale. Most filters can not stop them so a DIY mask with layers of cloth, activated charcoal or paper towel isn't going to work. Just possibly bubbling your breath through a liquid, ideally a sterilising liquid might do some good.When people sneeze they eject millions of water droplets which contain virus particles. Thes may be stopped by a simple mask BUT they generally drop to the ground very quickly under gravity because they are relatively heavy.Usually a mask is best applied to the one who is sick to prevent them ejecting these droplets into the air. Surgical and medical masks are worn for the same reason not to protect the patient but to stop the doctor/nurse breathing over the patient and giving them more problems.A full hasmat suit will have HEPTA filters or be self contained, these trap very small particles typically around 3 uM by electrostatic attraction to the filter fibers rather than a very small mesh size. Usually they say 95 to 99 % of > 3 micron particles will be trapped. however you only need a single Virus to get through.Don't mix in large public groupsDon't touch surface others will have touched before youDon't touch your face at allWash your hands regularly. EVERY time you go out and return. When you enter a building and when you leave.The virus enters the body through the mouth, eyes or nose assuming you not getting a contaminated blood transfusion.

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  • https://electronicsarea.com/temperature-gauge-circuit-using-lm324-ic/here you go.

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  • Look for a problem you can solve.Look for something that you are capable of doingLook for something you can affordLook for something you understand.

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  • yes - No. It depends on what your trying to do. You need to examine he spec of each carefully. Are you trying to save a bit of cash? The Picaxe (www.picaxe.com) is going to be perhaps the cheapest.

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  • PM is - I think - generally regarded as a closed system. ie self powering + the ability to draw some energy from the system.Changing the definition isn't changing the reality. One can argue that hydroelectric power for example -which is essentially free gets it's energy input from the sun. Changes in the way we utilise energy are going to come, Why not use solar and or wind power to drive up a big flywheel, then draw power from it when it is dark.Why not use solar power to draw a train up an inclined track then allow it to run down and generate electricity after dark.Or you can drill a deep hole, use cheap solar to wind up a weight, the drop the weight into the hole and generate electricity how much well depends on the weight and depth of the hole ubt it is within modern techology..

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  • https://www.google.com/search?q=alternator+wiring&sxsrf=ACYBGNRB2VkFgSa6uARP6S6vz44blAc_3Q:1581349727801&source=lnms&tbm=isch&sa=X&ved=2ahUKEwjV96nmqsfnAhVCZcAKHSpcBqEQ_AUoAXoECA4QAw&biw=1920&bih=937#imgrc=LZBq4HrbNmAKyMGoogled it.

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  • Driving Simulator Seat

    English fine - Looks super cool. Nice! :-)

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  • How to Ask a Question in Instructables.

    More than likely You need a reasonable amp that has overdrive functions and Fuzz or an effects pedal with these functions. https://www.youtube.com/watch?v=vRSL3u9uuGc

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  • Your asking this in the wrong place ask it again herehttps://www.instructables.com/workshop/community/more people will see it.In the mean time try searching on line for the name of your product and the fault to see if this has happened a lot to othersGive as much detail as you can so people might be able to help.

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  • Mine is 52 inches long front to back. The rest is a matter of taste. 1220 mm is that helps. These measurements are in the diagrams in the instructable. It is 500 mm wide. bgut can be as wide as you need. If you give me a link to an image of a seat you like I will size it and put dimentions on the image for you.

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  • Ok DXf files can give people problems. I can open it HOWEVER all the dimensions I used are in the instructable and as a PDF file. You should be able to sort out how to build your version from these.I have since then made a simpler version that has a central spine rather then build a box. this takes up less space and less material to make.I add a Jpeg image here of that build - I no longer have the photographs sorry.There are no dimentions on this because it all depends on how tall you are and what equipment you have but it isn't difficult to work it out. Mine was about 6 feet long from front to back.

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  • rickharris commented on memestra's forum topic Drafts

    YEP me too. Another failure.

    If I log out and back in I get to the drafts HOWEVER that isn't the point.

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  • I dislike the "pain to my friends - some friend you are" However in my youth chickpeas were the preffered ammo, or dried peas when the pea shooter was consficated.

    Mix pepper with a small amount of plaster of Paris, just enough to get it to hold together.

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  • It's a demonstration you often see in school science labs. ;-) The picture tells it all.

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  • A relay would be the standard choice and will be fairly simple if your not too electrically familiar.Alternative would be to use an FET as a switch.

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  • My choice would be to 3D print the squares and mount an LED in each one. Light scatter is a big problem with multi LEd displays. You could hand make the same thing in something like plasticard.

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  • rickharris commented on SaiV72's forum topic Cotton picker

    I am no expert but have seen cotton harvested using a vacuum kind of like a leaf blower in reverse.

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  • https://www.instructables.com/howto/solar+tracking/projects here

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  • IF this were me and I didn't have the means to turn the rod down to fit the bearing I would buy a rod to just go through the hole in the bearing. Check the specification for your bearing for the right size or measure it.Run a nylock nut onto the rod but the wrong way round, put on the bearing and run another nylock nut on, again backwards - because of the shape of the nut this will nip the centre of the bearing neatly.See image - click to expand.you can make a suitable sized hole for the outer diameter of the bearing.

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  • rickharris commented on NStarwoman's forum topic Dog bowl stand.

    https://www.instructables.com/howto/dog+bowl+stand/loads of projects to do this here.

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  • If that is a door pillar then it is structural. At least in the Uk it would need to be welded.

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  • Should be possible thingiverse has several available.https://www.thingiverse.com/search?q=combination+lock&dwh=85cecf65a7941f

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  • Sounds possible. A lot of plastics will shrink when heated. Perhaps heat the finished product with a heat gun or heat the bolt with a blow torch to get a better imprint of the thread.

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  • A lot depends on your skill set. Commercial water level gauges are available at reasonable cost. (see amazon for example)in manufacturing your looking at contact or non contact methods. Contact: float and either a potentiometer to give an analogue reading or a switch to give a simple full or empty light.Non contact - you could look at ultra sonic sensors or even lasers but in most cases the vessel is simply weighed.I would buy a level alarm.

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  • My optician uses a flash to illuminate the retina, this is so fast the pupil has no time to contract. Your sitting in a semi dark room to make your pupil dilate.

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  • IF your invention is commercial - the chinese are likely to copy it when it hits the market place - Ask yourself this: Are you able and willing to fight an international court case to protect your patent. IF your patent is going to generate a LOT of potential cash - My choice would be make a prototype, get the patent and sell the idea to a commercial manufacture and let them worry about the chinese.In general the patents that are worth protecting are for fundamental concepts rather than actual hardware - It;'s generally too easy to get round a patent by changing something a little..

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  • The load cell forma one resistor in a wein bridge You can measure the current aross the bridge a small change in resistance makes a BIG change in current flow.A search for load cell circuit diagram will show you many choices.

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  • The usual way is to enclose the bag in a vessel and suck out the air. Allowing normal pressure air to inflate the "lung"You need something that has high volume rather than high pressure - as suggested bellows could work.

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  • Helps a lot if you post an example. The Zenner diode standard symbol is a diode with a small additional bar to the cross bar like this: ¬

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  • rickharris commented on randofo's forum topic Recent Feed Page

    I can't get to my in box unless I log out and back in again.However prospective changes sound good. ;-)

    Chrome Win 10

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  • rickharris followed 3D Printing channel
  • rickharris commented on LyndaA11's forum topic Green bamboo

    Should be OK, It will dry out in time BUT it may not stay straight.

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  • https://www.youtube.com/results?search_query=COS+play+costumestry watching some of these videos on costume making.

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  • Wood can be stained if stain is waterproof.If you want the stubs to be permanently mounted I might consider PVA glue However they won't come off again and it will effect the look of the paper. (make it slightly glossy)If you want to preserve the stubs then your going to have to find some system that will not harm them - Look at how stamps are mounted in an album.

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  • rickharris commented on izzys13's forum topic Help plz:)

    1. Start searching the internet there are lots of sites with craft ideas on them to get you started.2. If your intending to sell, you need to know what your work materials cost, how much time you spent on it and how much you want for that time. A good way is to look at what others are charging for similiar items.3. ETSY is one craft site for selling, Ebay of course but look around you locally, there might be shops that will display your work on a sale or return basis for a percentage of the price.4 Flea markets (car boot sales in UK) - good place to take a stall5. Local Market place, generally stalls don't cost much.You don't say where in the world you are but postage costs might be an important consideration.In this day and age I generally suggest to people they need to do the jobs other…

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    1. Start searching the internet there are lots of sites with craft ideas on them to get you started.2. If your intending to sell, you need to know what your work materials cost, how much time you spent on it and how much you want for that time. A good way is to look at what others are charging for similiar items.3. ETSY is one craft site for selling, Ebay of course but look around you locally, there might be shops that will display your work on a sale or return basis for a percentage of the price.4 Flea markets (car boot sales in UK) - good place to take a stall5. Local Market place, generally stalls don't cost much.You don't say where in the world you are but postage costs might be an important consideration.In this day and age I generally suggest to people they need to do the jobs others don't want to do or don't have time to do:Gardening, takes little real skill and can be a regular income in the summer months. Walking dogs, at least in the UK, this can be a big business, people have pets but are working and need someone to look after them whilst on holiday or whilst they are at work.

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  • I used to have a job where we were standing around for long periods waiting for aircraft to arrive.We started discussing the future - I was around 20/21 at the time so about 1969/1970.We agreed that more or less everyone would be retiring at 50 because so many jobs would be done by Robots and the work field would need to be cleared so younger people had jobs of some kind.Leisure would be a BIG industry so people would be occupied.Plastic cards would be used to pay for transport and food. Most food would be produced underground with artificial lights in automated systems, seeds in one end and plants out of the other, Animals also would be kept indoors most of their lives.Homes would be connected by an underground conveyor system to the shops you would dial up your shopping list and it woul…

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    I used to have a job where we were standing around for long periods waiting for aircraft to arrive.We started discussing the future - I was around 20/21 at the time so about 1969/1970.We agreed that more or less everyone would be retiring at 50 because so many jobs would be done by Robots and the work field would need to be cleared so younger people had jobs of some kind.Leisure would be a BIG industry so people would be occupied.Plastic cards would be used to pay for transport and food. Most food would be produced underground with artificial lights in automated systems, seeds in one end and plants out of the other, Animals also would be kept indoors most of their lives.Homes would be connected by an underground conveyor system to the shops you would dial up your shopping list and it would appear in your home automatically.Transport would be totally automated with dedicated roads for trucks and cars.Education would be mainly at home via a (TV I thought then as computers didn't exist as we know them today)The parents would be held responsible for their child's learning, with severe punishments for letting their attendance fall off. Most punishment could be by limiting access to entertainment systems - easy if the government controls your access card.The education system will monitor progress, if you fail a progress test your automatically directed back to the relevant section for review. if you continue to fail then a human tutor will be notified and step in to help you over the problem. No progress unless you can demonstrate you understand and can apply the knowledge you have learned.Socialisation is taken care of by compulsory attendance at various activities not part of the learned curriculum. ie. clubs these are monitored by humans of course but periodically you undertake psychometric tests to make sure your adjusted. Maladjusted people, when identified, are given appropriate psychological support. The idea is to avoid criminals and malcontents by education early in their development.Lots of other things, some of which are now true such as CAD CAM and 3D printers.

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  • rickharris commented on iceng's forum topic Your full of Bugs !

    :-) I find it hard to see you pondering over a lot of cardboard bits. However thanks for the reply.Expert definition: - X is an unknown quantity and a spurt is a drip under pressure!

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  • rickharris commented on sher dil's forum topic Train Direction

    These sort of things are very common on the internethttps://www.google.com/search?q=model+train+controller+circuits&tbm=isch&source=univ&sa=X&ved=2ahUKEwjp_d2sn_zhAhX4QxUIHQTrCM8QsAR6BAgIEAE&biw=1920&bih=937shows a lot of circuits and following them will take you to construction pages in most cases.be carefull when operating with mains - It bites HARD!

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  • Battery or more correctly power sources have a LONG way to go to make the electric car viable (despite what the UK government thinks).It's really hard to beat the energy density of petroleum. A lot of available power in a very small space, easily reloaded in a few moments and pretty commonplace. ie. what you can't get from underground you can make in the lab from plant based raw materials.I think the future may be the hybrid, a small efficient engine - perhaps a stirling type, running on biofuel with efficient capture of the emissions, this drives a generator to charge onboard batteries. Around the city you are almost stationary as much as you are moving so the amount of power used is low ad easily topped up. In the countryside, you get used to driving to suite your energy source ie. you …

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    Battery or more correctly power sources have a LONG way to go to make the electric car viable (despite what the UK government thinks).It's really hard to beat the energy density of petroleum. A lot of available power in a very small space, easily reloaded in a few moments and pretty commonplace. ie. what you can't get from underground you can make in the lab from plant based raw materials.I think the future may be the hybrid, a small efficient engine - perhaps a stirling type, running on biofuel with efficient capture of the emissions, this drives a generator to charge onboard batteries. Around the city you are almost stationary as much as you are moving so the amount of power used is low ad easily topped up. In the countryside, you get used to driving to suite your energy source ie. you don't use power unnecessary just to go faster. Some kind of automatic control is probably required to combat the "heavy foot" syndrome.Many years ago (1060's) I proposed a town system where driverless cars followed a wire buried in the road surface, they picked up power from a slot in the road surface, i guess a contactless system could be devised these days. The guided nature and a central control system overviewing the onboard intelligence seems to me to be the way to go in town or city.The guidance wire would be easy to lay just a cut in the road surface, the rest is well understood robotic technology.

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  • Very useful and interesting and thanks for taking the time. More food for thought.

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  • 30/april update the link now takes me to the correct place, however the draft instructable link still tales me to the front page.

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  • Log out log in same problemLinks from my profile page all return to the main page.If that's any help.

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  • Many thanks for replying, Golf cart motors will work well for your application where torque is more important than speed.Thanks for the link.

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  • Thanks - again if I click the link in the email it takes me to the front page. not to your reply.

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  • Hi,There are a lot of youtube videos on technical drawinghttps://www.youtube.com/results?search_query=techniCAL+DRAWINGOf course much these days is done in CAD. And that depends on the package your using.NOTHING replaces practice. Understanding perspective and isometric drawings until you can do them freehand is a good skill to learn.If You have specific questions please ask, otherwise spend a lot of time drawing things around you. I maintain ideas sketch books I have perhaps 20 or 30 over the years where I work out ideas, sketch plans and inspiration. It's a habit worth culturing.

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  • IF this worked, Then the system has been very unreliable and erratic over the past week or so..Now my REAL question that I asked a week ago.My electric racing car had a 250 watt DC motor that weighed around 4 or 5 Kg.Now this motor claims to be 4 K watts. https://hobbyking.com/en_us/turnigy-c580l-580kv-brushless-inrunner-motor-4000w.htmlOther than electric bikes I seen lightweight cars or velomobiles using such a motor why not. Am I missing something. The RPM will be very high but a suitable gear box isn't beyond engineering.So why are they not in common use? $000 watts is 4000 watts in my book. (about 5.5 HP)Expert opinion?

    The original post exists here https://www.instructables.com/topics/BUDSASSJUMXP9H7/It just isn't seen by the search engine. I wonder how much else gets "lost"

    Thanks

    Thanks for that DU you simply confirm my thoughts.In the original post I put a lot more details but lost the will to live after the 3rd try.my original motor was indeed a brushed motor although 24 volt running at a max of 17 amps. At this level it got fairly hot and we cooled with a fan. The 250 watt rating was continuous use. 3000RPM geared 14:1 to the wheels. to give a theoretical max speed of 35 MPH.As brushless motors are fairly cheap my second thought was you could run 2 or 3 or 4 in parallel to increase the available power. Even a one or two Hp would be fairly significant in a very light single person car on the flat.

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  • rickharris commented on iceng's forum topic Your full of Bugs !

    IF this worked, Then the system has been very unreliable and erratic over the past week or so. I am unable to post a topic or question so Ill hijack this as it's really a bug anywayNow my REAL question that I asked a week ago.My electric racing car had a 250 watt DC motor that weighed around 4 or 5 Kg.Now this motor claims to be 4 K watts. https://hobbyking.com/en_us/turnigy-c580l-580kv-brushless-inrunner-motor-4000w.htmlOther than electric bikes I seen lightweight cars or velomobiles using such a motor why not. Am I missing something. The RPM will be very high but a suitable gear box isn't beyond engineering.So why are they not in common use? $000 watts is 4000 watts in my book. (about 5.5 HP)Expert opinion?

    I can't see my draft instructables or anything else clicking the link takes me to the main page again.

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  • They look like CO2 cartridges as used in Soda Syphons - a Local restaurant may be able to help you. Alternatively do you have a Shooting club that starts users on Bb guns.https://www.alibaba.com/showroom/empty-co2-cartridge.htmlAllibaba listing for empties.

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  • nswered elswhere - posted twice

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  • They look like CO2 cartridges as used in Soda Syphons - a Local restaurant may be able to help you. Alternatively do you have a Shooting club that starts users on Bb guns.https://www.alibaba.com/showroom/empty-co2-cartridge.htmlAllibaba listing for empties.

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  • rickharris commented on iceng's forum topic Your full of Bugs !

    :-) A lot has changed Iceng, some even for the better! Any specific bug that is bugging you?

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  • Hi, As a, now retired, Design teacher a number of my school projects, The electric racing car, the geodetic greenhouse The microprocessor starter and how to do you technology course work are all written up here.

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  • The continuous output current of the L293D is ONLY 600 Ma.If you apply a larger load than that it will get hot and the thermal cut out will shut it down.The enable and control signals should be 5 volts..The supply (for the load) can be up to 36 voltshttp://www.ti.com/lit/ds/symlink/l293.pdfData sheet.

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  • Anything that can get it red hot. propane is fine for small items, Oxy acetylene for bigger things. Gas and forced air is also a good option if you don't have access to oxy acetylene.

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  • Interesting your profile used to show you but now seems not to.instructables should tell you when your current membership is running our and give you a chance to activate another.

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  • 1. You need a good fast air flow.2. Your air outlets need to be vertical3. your targets need to be very light and a ball or cone to stay in the air stream.4. try balancing one of your balls on a hair dryer air stream to get the idea.

    translation:"I have tried to make this instructable but unfortunately it isn't working.I made it just as your instructions but it still didn't work.has anybody made this and got it working?i tried with a compressor but don't know if the air flow was too small."Who says all those years in the classroom were wasted! :-)

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  • Technically your trying to braze.The flux is to clean the metal and prevent oxidationi generally use Borax as a flux, it's good and cheap for brazing and silver soldering.This is how I would do it.1. Clean both wires2. Make sure they are in close contact and heat then dip in flux.3. Heat brazing rod and dip in flux to coat.4. Heat joint to red hot applying the brazing rod - when temp is right it will soften and flow into the joint.5. allow to cool. brush off excess flux.

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  • Steve's offer is probably the best you will get.

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  • rickharris commented on Downunder35m's forum topic Funny login bug!

    :-) your making the assumption that I would care!No I cleared my browser Cache to enable logging in again. No mystery.

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  • rickharris commented on Downunder35m's forum topic Funny login bug!

    Many thanks, I haven't been able to log in for a week or so until today. Appreciated :-)

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  • Ok I take your point.Lets see if my experience is any use to you.1. Your going to need to start by writing a really detailed User Requirement Specification (URS) for what your client wants - detailed down to the last $ of costing, the sizes, the expected outcomes - this is YOUR bible - if you can respond totally to that specification your client will be most happy and the project will be a success.2. your going to take that User Requirement specification and write your response A functional Specification (FS). this will detail HOW to do the job, what is required for each element, costings and any other information needed to do the job - eg. your going to need to locate and get the specification for a suitable sensor to do what the URS wants. That will probably (but not limited to) be int…

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    Ok I take your point.Lets see if my experience is any use to you.1. Your going to need to start by writing a really detailed User Requirement Specification (URS) for what your client wants - detailed down to the last $ of costing, the sizes, the expected outcomes - this is YOUR bible - if you can respond totally to that specification your client will be most happy and the project will be a success.2. your going to take that User Requirement specification and write your response A functional Specification (FS). this will detail HOW to do the job, what is required for each element, costings and any other information needed to do the job - eg. your going to need to locate and get the specification for a suitable sensor to do what the URS wants. That will probably (but not limited to) be interfaced with a microprocessor. You need to identify the relevant inputs and outputs your going to need so you know how big (or small ) the microprocessor needs to be. 2. You need to detail to the point of identifying ranges of accuracy etc, Materials, the fluids your dealing with and any other restrictions you can possibly think of that apply to the project. (this isn't easy - I used to do this as a consultant for big money but the more thorough you do this the easier the project will be.)Note:The sensors your going to buy and MUCH of what you do after that depends a lot on what they need.to be continued...

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  • https://www.google.com/search?q=Automatic+PH+contr...Do the research

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  • More details needed: chill down to what?do you need physical presence?Partner to do what? electrical, mechanical, Software?

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  • rickharris commented on zikkij's forum topic Code for website

    That web site is created as a blog so anything you fancy really. i use Blogger from Google - works for me.http://nz-2015rah.blogspot.com/

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  • You don't say WHY you need to do this - but your highest energy density is going to be a lead acid car type battery (that's why they use them in cars)Couple that with a suitable sized inverter and you have a semi portable power source.HOWEVER I would approach this in a different way and build a PC suitable for battery use. having used the raspberry Pi I found it to be fairly easy with LOTS of support.https://www.instructables.com/howto/PI+PC/

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  • rickharris commented on AdvanŽ's forum topic Stairs redesign

    1. Stair gate at top and bottom Preventing accidents is easier than dealing with them2. Box in the open side but use safety glass so you keep the open view.3. Fill in the gap between stairs.4 they are really steep I think in the UK they wouldn't meet building code - i guess nothing to be done about that.

    Use safety glass or Plastic. Safer but lets light through.Or use a net mesh of some kind.

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  • Not that I know about. But your PC probably has an HDMI input on it.

    For me I would play the HDMI signal through my PC, Use Audacity (free) to record it. Then play the second one and record it. Use audacity to mix both sound captures and output as you want.

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  • https://www.instructables.com/howto/velomobile/

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