Workshop Topics


Tesla's earthquake machine - was it just a practical joke?

Nicola tesla, in his early years, was not shy when it came to use science through direct contact.Most of it we would call today playing practical jokes on students and friends alike.His harmonic balancer got the nick name earthquake machine.I won't go into the story how all came together, you can read the story on Wikipedia or other sites to the fullest of your imagination.Howver, I would like to go into some details of this invention.Or better: I will try to explain my view on why this machine might have actually worked close to what the story tells....Studying old paents and other documents is no fun and not always you can reach any valid conclusions from any of it.I mean, if you coud then you wouldn't need a patent for it.Some things however are so good, so special that they never get a patent, the company keeps it as an iternal secret.Same way a brewery won't tell you the exact recipe for the beer they make ;)The harmonic balancer has very little to go with except stories and some comments Tesla scattered here and there.So let's start by some claims Tesla made about this machine:1. It has a free swinging mass.2. The mass is balanced using "air springs".3. It usues very little energy.4. It finds the harmonic frequency of the object attached to automatically.If you think about the above you could say right away it is bogus.But think about the terms and language of the old days ;)Add the fact that Tesla never really gave any direct answers to how his inventions actually work and you see where I am going here.Point 1 and 3 are easy to imagine in many ways.Number 2 on the other hand contradicts itself at a first glance.But, if you place a piston with a good mass and good seal into a cylinder nd close both ends while the piston is in the center....A bit like these to shake emergency torches and flashlights.With that idea in the back of a head one can imagine shock absorbers and more.And a "mass" "swinging" in such a sealed tube would certainly be subject to the "spring" force of the air being compressed in front and the forming low pressure on the other end.The last one however had me stumped for almost two years with me getting nowhere.A mechanical system can't adjust itself to the harmonic frequency of anything....Then I saw a collection of funny videos.One of the clips had about 100 metronomes standing on a board.The board was place on two rollers so it cold move freely from side to side.All the metronomes wre set to about the same timing.But of course you just can't start them all at once or even so they swing in sync.After just a short while though, one by one found a matching partner on the board.Faster ones slowed down, ones totally out of sync seemed to miss a beat here and there.And then it hit me!Hundret swinging masses on a board and the board moves together with them!Once all were in sync and harmony the board moved basically exactly the same way sidewas as the single pendulums above.Number four finally solved :)How though could one try to replicate this impossible invention these days and without knowing any exact details anyway?We know it used one or two electromagnets.These moved the mass back and forth horizontally in the machine.However, it was more formed like a T wih a fat base.Tesla needed a dead simple way of doing with electricity what the metronome does just mechanically.If you have a little mass on a spring and one contact on the spring plus another on a tube that is around the mass - what do you get?No, not the trigger for something really nasty when you pick it up...Right! You get a motion detecting switch.A bit like our gyroscopic sensors do now in our phones....And if you cut the tube lenghtwise you end with two opposing contact to switch two magnets on depending on what side of the tube is hit by the mass (contact) swining on the spring.Try it out with a spring from old pen and a screw inside as a weight - quite sensitive if you get the weight right.Some drawing suggest he height was about the same as the width of the machine.This would suggest the contact was actually hanging upside down, so it could swing in the wider base.A bit of fine and very flexible opper braid with a weight would make a nice pendulum here....Do a little experiment first though ;)Make a sturdy frame or if you have none try a truck. ;)If you place the frame on wheels and a pendulum with just a string and some sinker at the end - what would happen if you move th frame sideways instead of swinging the weight?Inertia keeps the weight in place while the top mount of the string moves away.And if the weight stays in place for just a fraction of a second before starting to move with the frame?Correct! since the angle of the string changes, the ball appeas to move up.Not really by much but enough for an electrical contact to open....We have some ideas now on how those electromagnets might have been triggered by Tesla, what about the mechanics of the moving mass that claimed to have created earthquake like results?Precision is no problem these days, just check these toy kits to build your own Stirling engine or you trusty old Swiss Army Knife.And even a second hand air cyclinder and piston can be modded to act like a free swinging air pump.Only question that really remains would be how to match the mechanical system with the electircal?We have two seemingly independent masses, one to make things move violently, the other to energise the part that make the first mass move - or to be precise to give it a tiny push in the right direction.What does mean you wonder...Let me try to simplify it down a bit.....If you push someone on a swing you can have a very hard time by working against the mass of the person sitting and enjoying the ride.Or you could give the person just a tiny push - right when the swing starts from the highest point to go back.Could that mean it is really as simple to build as Tesla claimed?If the top mass is limited by how far it can swing FREELY before the air pressure works against this movement then we would only have to set the length of the pendulum so the contact happens right at that point on the x-axis of the top mass.Ok, and how would that make anything swing at all?If the top mass is first energised there is nothing to stop or influence the movement, except the "air springs".So it totally overshoots like those metronomes on the board.It swings back and closes the contact on the other side of the movement way early as well.Now the electromagnetic impulse from the second movement actually works against the moving top mass.And this swinging of total non-control continues while whatever the thing is mounted to also starts to move, even if it is just fractional.Over time both swings, from the machine and the object, will get to point where they influence each other in a "positive" way.For Tesla's experiment one would say negative though as it was quite violent in the end.Little by little both swing will get closer to being in sync and with that in resonance.The electromagnetic push however continues....Only that now the top mass of the machine is in sync with the thing it is mounted to.The machine became you standing behind a big swing and trying push someone higher and higher....It is all just a theory though and any minor earthquakes that might register around my area are pure coincidence ;)

Topic by Downunder35m    |  last reply


What to buy?

Hi Guys,I would like to make small wooden boxes, it's my first time would you advice which table with saw should I buy? Greets ChrisPs It should be small and not super expensive.

Topic by ChrisRydzewski    |  last reply


Want to build a automatic opening drawer? Answered

could i use a dvd tray as the actuator if it is under a light enough load? what is the max it could probably open? thanx for any help you can offer

Question by JustinJalapeno    |  last reply


Cleaning up STL files for 3D printing properly?

Every now and then I find a nice model on Thingiverse or such places that I would like to print.Quite often though these models come with errors.No clue why people upload them for 3D printing if the printing software can't print them....Anyway, there are quite a few online place that fix a model and make it watertight, remove flipped faces and more.Usually with quite good results unless the model is really crappy.What I miss though is a program or online service, preferably free of course, that can actually simplyfy a model to match a printers capabilities.For example a scanned object of just a few cm in size can come with over 100mb in file size with ease.There are programs able to modify a mesh, shrink it or even reduce the triangle count.However those usually still fail to address the problem at hand.Required details go missing and sometimes entire shapes change in important spots.A normal FDM printer comes with a 0.4mm nozzle and is capable of 0.1mm layer hieght with realitve ease.There must be program or service that utilises this properly to create new and in size reduced model.It is just a total pain to use 3 or 4 different programs to modify a simple lithopane just to get some custom text onto the stand.Same for creating multiple print jobs for it as it often results in bad adhesion.What I really would I guess is something where you enter your prefered layer height and max resolution based on nozzle size to get an optimised STL in return.I know your nagging question already: Why bother?1. If you have a STL file of less than 1mb and make some simple modifications with Blender, Meshmixer or whatever, then you can end with a file of way more than 20mb in size and with a complexity that was nowhere in the original."Fixing" a bad file with these apps is easy but again result in massive file sizes or massive loss of detail.2. Mechanics...It really makes no sense at all trying to make your printer create structures finer than 0.2mm - you just won't see it with your naked eye anyway.Especially complex, scanned objects often result in perimeters that enlarged look like someone was holding a running jack hammer while making the perimeter.In return your printer can create quite similar sounds and most importantly the print time goes up for no good reason at all.3. I just prefer simple and clean models.I want to be able to make simple adjustments to a simple object without the need for 32GB of RAM and a server tower to house several CPU's.Is there any such app or service already out there and I just missed it?

Question by Downunder35m  



Washing machine motor on an electric vehicle?

Hello, i already asked a question about a car starter as a Motor for my Electric bike project. I got bad news from the answers, so I wanna use a washing machine motor.  My question is, do i need 240V to power it? Or it has like a transformator in the washing machine that makes the voltage lower? I never opened one..

Question by dsirotic    |  last reply


Can I use 60ppi polyurethane to filter solder smoke?

I am going to make myself a little rig. Two fans with some kind of filter sandwiched in between. I was wondering if polyurethane filter would work because I saw it and it was extremely cheap. 60 ppi seems like the best filter quality I can find. Then again I don't really know what I'm talking about. If someone could explain to me why this is a bad or even a good idea that would be appreciated. Also any recommendations on anything else I should use instead. :)

Question by Inblackandwhite    |  last reply


Has anyone ever built their own rooftop luggage or cargo box?

I have had a couple and for 2 & 300.00 bucks or more, there's really not much to them. It's just a hollow hinged plastic box, made to be a little aerodynamic and strapped to an existing luggage rack. I find it hard to believe that a home made version couldn't be created as sturdy if not sturdier, hold more and last longer. I was thinking maybe pvc, conduit, or even wood framed. Just curious. Thanks in advance for any helpful input.

Question by SAWWAS72    |  last reply


Go-kart upgrade: plastic "wheels" to real tires Answered

My son received a Kettler Go-Kart (2nd hand adventure) for Christmas, and it's a lot of fun, even for the mom who crams herself into it to give chase to the kids (make great tight turns). Goal: take it a bit more off-road than asphalt and smoothish ground. Currently: Plastic, rear wheel drive wheels (think Hot Wheel front wheel material we grew up with). Where I'm at, after perusing the internet for all things pedal go-karty: I feel like the front wheel assembly will be pretty easy to replicate. The nature of rear wheel drive, which stays straight (fixed) is the challenge. Images attached. What's the answer to the rear wheel drive assembly? How to replicate rear fixed driving wheel with wheels available at the big box store, or is there another question that needs to be answered first? is the chief concern prior to fully disassembling the go-cart. And/ OR, What are the magic words for finding the "wheel" answer? Thank you in advance!

Question by An1more    |  last reply


What is this

Need help identifying this tool

Question by kaptain1    |  last reply


What kind of switch to operate and bypass motion sensor security light?

I would like to be able to manually operate the light for when I need it to stay on continuously, and then have it operate on the motion sensor when I am away from it. Basically I have a motion sensor light mounted above the entrance to my shed/ workshop, and sometimes I need to set up my sawhorses outside of the shop to do work at night and the light is sufficient, but when I have been still too long, perhaps doing some figuring or whatever, it goes out. I don't want to have to continue to wave my hands about to get it to come on every time it goes off. Do I need a double pole single throw switch, or a single pole double throw, or what(is a three way light switch a SPDT- [single pole double throw] switch)? Is there a way to wire it to a single switch where I could flip it over to one side to operate continuously, and then flip the switch to make the light work off of the motion sensor when I have gone in for the night? Please forgive the ignorance. I just can't envision it in my head. Thanks.

Question by stevecinstrfme    |  last reply


WW1-WW2 German Bayonet help

I was wondering if anyone can help me identify a German bayonet I have. I’ve done a bunch of research with my friends and think it was made during ww1 and reused in WW2. Some details are there’s a letter “J” on the spine and a filed out “3183” on the tang and scabbard I think those are the numbers I’m not completely sure but from the scabbard it seems to be “3183”. The tang serial number was filed out except the last number “3” and on the scabbard “813 (blank)”. And stamped over the scabbard is “3837” and on the guard “3887”. I believe it’s around 10-14 inches. I don’t know if this might help but just wanted to include it just in case, thanks.

Question by jpfreese    |  last reply


Any ideas for a printer that can print onto a bound notebook's pages?

Hi, I've been wondering about this for a while. I would like some sort of machine that can print onto the pages of a book that is already bound. For example: If I have a leather notebook and I want to print a poem or some such onto a page I would then load the book into the printer and the printhead would move around the page to print the required text (as opposed to the page being moved in a normal printer). I was wondering if anybody knew of an existing tutorial, product hack that might allow me to do this? What I have found is the following: -Axidraw - this is probably the closest to what I want but it is quite expensive. -Handibot - this does what I had in mind but for cutting. My ideal would be something like this that prints. -Printer modification - another step in the right direction but this only works if the material being printed on is of a fixed height. The constraints I foresee is the fact that the pages in the book need to be kept flat and that the height of what is being printed on can vary. If there is a solution out there I haven't been able to come up with the search terms to find it. Any help will be greatly appreciated! Thanks, Marcu

Question by Wormlamp    |  last reply


Advice on building a RC projector enclosure

I have a video projector mounted on the underside of a moveable wood panel on my patio ceiling (see pic, the yellow plastic would be removed) that I'd like to build an enclosure for that won't break the bank. Since it is too high to reach, ideally (with some help) I can construct an enclosure for when it is not in use, that I can remotely adjust to use the projector (for example; via linear actuator or screw drive, etc.). The challenge is the projector has fans and cooling vents on the sides which need clearance to be effective, so three sides of the projector must be clear (the third is the front w/ the lens). All told, the vertical distance of movement for this clearance would be about 4-6". While I'm not well versed in this kind of small motor/arduino/circuitry construction, I'm pretty handy and am confident I can figure it out with some help. I have found many examples of RC box openers with hinged lids, but in all these hinged designs there would not be enough side clearance for the vents. I hope my description was not too confusing, I am open to any and all suggestions. Thanks!

Topic by STRobo  


Spring loaded bicycle braking system , Does double duty as a Propulsion aid through gears . Feasible?? Answered

  Basic Idea: When used to help slow(not primary brakes) a strong coil or spring is tightened to aid slowing. When maximum amount of tightness is reached the coil disengages somehow, The coil could be kept in the tight state until released for use for a burst of propulsion through reverse gears . Totally non-electric and light. It would be ideal for stop-and -go bike commuters , up and down hilly areas ,etc.         Same idea could used for smaller cars, motorcycles,etc. Has this been used before ? Feasible ? Any critiquing of the concept is welcomed .

Question by BtheBike    |  last reply


Where can I buy mini, really slow, 3.3v to 12v motors?

I'm looking for little motors that are about 15 - 20 rpm and that will run on 3.3v to 12v (5v would be great since I want to use usb for power). I've no idea where to start looking. Any help would be greatly appriciated. Thanks.

Question by aliasjanedoe    |  last reply


Flashforge 3D printer freezing and stuck before the logo is fully on the little screen

I really like my Inventor, it is reliable and a strong work horse.What I really hate(ed) though is the thing freezing up when you think you can quickly print out a part you just broke.The symptoms are the same throughout the Flashforge range, so let me sum it up quickly to get on the same page here.The printer worked fine for a while.You turned it on one day and the logo is not fully displayed, about the top 20-25% are blank and the printer get stuck on boot.In some cases waiting for 10 to 15 minutes makes the printer finnish the boot but it will only work like this a few times.Once the printer is seemingly dead there is, or better was, only the official Flashforge solution to make it work again.Take the machine apart and the SD card out, replace the firmware files on it after formatting the card on your computer.I did the official solution a few times and it works just fine, even if you just delete the files on the SD.However, there is a better option I found during the last few weeks of heavy printing.Ever noticed how the printer keeps all your printed files stored on the SD?A nice way of handling if you quickly need to print another part.Totally useless though as the last part you printed is always the last part in the ever growing list of files to go through on this tiny screen.Long filenames are bad, having more than about 50 .gx files on the internal SD is bad as well.Combined they cause our freezing problem and the printer getting stuck on bootup.I have not done a count but the amount of files until it happens seems to be quite consistently.Really complex models seems to make the problem worse, especially when trying to scroll through the listed files on the touchscreen.I now did about 4 complete rounds of replicating this problm in all variations I can think of.From this I came up with quite simple solution that seems to be nagging a lot of people out there.The solution to prevent your Flashforge 3D printer from freezing up:Only keep on the internal SD what you know you might have to print again in the next few days.Manually delete all other .gx files whenever you have the time to spare.Try not to have any more than about 20 print files left on the SD at any given time.I stuck to this and have now printed about 300 parts without any freezing up during boot.Hardware solution if keeping the amount of print files on the internal SD low is not an option:Be it in a school or makers community, sometimes you just can't keep the amount of print files ending up on the SD in control.And forgetting to manually delete the files on day results in a stuck machine on another day.To avoid taking half of the machine apart while putting iton the back you can mess with the SD card reader on the mainboard during the next firmware replacment and formatting on the computer.SD card extenders are available online.Usually just a ribbon cable with a SD card connector on one end and a "reader" on the other.As a last resort you can get one of these cables and install them so the reader part comes out at the bottom of the housing.Requires making a suitable slot for it in the cover plate though.I did this for a while and it was quite convient but IMHO not a long term solution.I contacted the Flashforge support with my findings and hope one day they will be able to address the issue in a firmware update to solve it for good.Until then try the above to keep going ;)

Topic by Downunder35m    |  last reply


What is your favorite Instructable?

Doesn't have to technically be an Instructable - any set of free diy instructions will do!

Topic by wolfkinara    |  last reply


I want to buy a 3D Printer

I have between a grand and two grand to buy a 3D Printer. What is the best 3D printer with preferably an enclosed body and definitely a larger than 12 in by 12 in by 12 in build area. It must not be resin and the cheaper the better with the best reviews the better

Question by PhatRATTY    |  last reply


My Infrared Sauna keeps turning off by itself mid program.

It turns on, heats up for about 1 to 10 minutes, then click, turns off.  What can cause this?  I usually unscrew the light bulb so it does NOT come on during the cycle, I like to sit in the dark and sweat!  When I screw lightbulb to turn on, unit immediately clicks off. I have been having some panel problems where the time keypad or the temperature keypad will not respond as well.

Question by WendyR63    |  last reply


Battery charger question

Hi,I have just bought a charger for my motorcycle.it was advertised as having a trickle charge function; which I believe is good for battery longevity ( and I only use the bike once or twice a week).However, it does not have a trickle charge function but it does have a pulse function ( which it recommends for motorcycle batteries as the normal ampage output is too high for small batteries).Thiis is meant to be gentle and does not create the bubbles caused by electrolysis, but is it worse or better for the battery than a trickle charger ?Thanks

Topic by FriendOfHumanity    |  last reply


Wireless Relay Light Control Help Needed

Attached is a diagram of basically what I'm thinking. The goal is to have multiple relay switches in a point to multi-point setup with a controller as the primary link back. The relays would have lights attached to them. So basically I want to be able to connect usb into the main controller and send a signal to the relays for example send a 1 code relay number 5, so the switch closes and the light turns on and set the time for 3 seconds then send a 0 code to shut it off. I am brand new to these types of products so my question is... based on this information. Where would I start? Are there particular modules that i will want to use? Are there any sites where I can purchase the modules already configured for what i want? I tried googling the idea but I'm not sure what exactly to search up. Ive tried things like. Point to multi point relay network. My goal is to be able to plug any kind of light into the relays like simple two prong led lights or an led light strip behind each of the relay switches, and connect to the main control board and use serial or ssh or some interface to send a command to the relay to turn the light on. Eventually I would like to write a script to automate the process of send the command to turn the light on. Then randomize it, such as, relay 2 on for 3 seconds/off, relay 6 on for 3 seconds/off, etc. Additionally, aside from the basics that I need to get started on the right track, How is power controlled? Does the relay have an onboard battery or do i need to put into the loop a battery that when the loop closes the light turns on? Any help with pointing me in the right direction is greatly appreciated. I am just not sure where to begin and I don't think my search parameters have been accurate enough to help me find any similar type projects to help guide me.

Topic by TheKuyaJames  


What is this hand tool? Answered

Got this tool with a bunch of other tools. It has some markings related to machine screws. Any help will be much appreciated.

Question by bageldoy    |  last reply


Position lock free stop seam type hinges

I am working on mechanical hinges. It's a case design for mobile along with hinge.i need some input regarding position lock seam hinges like the one shown in attached images/i am designing this case for ipad/tab.How exactly these hinges works ? and i need internal 3d model of these hinges? how exactly it look from inside? and what is prefered manufacturing method for making these type of objects ?

Topic by adityay17    |  last reply


How to Slow Down a 240Vac Electric Motor?

I bought a small, industrial motor and want to safely slow it's rpm.  Does anyone have any advice as how to best go about this?  I've looked into gearing and found this to be quite complex but understand that an alternative option may be to change the voltage received by the motor?  Thank you for any help you provide

Question by ambrosiaceae    |  last reply


Using solar salt instead of washing soda

Can I use solar salt instead of washing or baking soda for electralisas

Question by luvsjuicypuss    |  last reply


Rc transmitter and controller.

Hi Guys I'm ne to the rc world and I was just wondering if I lost my rc receiver would that completely deem my transmitter as useless or can you just purchase a new receiver. Many Thanks in advance.

Question by chris.france2008    |  last reply


Different grinders of the Dremel. What to use? Answered

I use a dremel-clone. It has a set of grinders of three colors: blue, red-orange, and pink, the three in the same set. I can't see differences in hardness, but it must be differents, so... Can you help me in what color use in which task? Thank for your time!

Question by infob    |  last reply


Is there an easy way to find a short or open circuit in a car?

I am trying to find a open or short circuit that is on a wire which is in a harness with other wires, on a 1986 Mazda B2000 truck. With so many of you having expertise in electronics, I thought here would be a good place to post my question. Does anyone have any suggestions how to find this open or short-circuit?I am open to the idea of getting a short-circuit-finder. Though I am not sure what features I should look for if I decide to get one. Does anyone have any suggestions?a) Does anyone know if these work well?b) What features should I look for If I get one?c) Do you have any other on a short circuit finder? type, manufacturer, model etcBelow is a link to a site that uses a short circuit finder to find a short circuit, and has information on using one: http://inliners.org/tech/tech6.htmlBelow is a link to a site that tells about how a tone generator is used to find a short circuit, in a home environment (I think this is how most short circuit finders work): http://askville.amazon.com/tone-gene...uestId=5912724I found some links that seem to show that it is possible to make a signal generator and tracer, but the pages with the schematics would not load. A list of tools with links to tools and their schematicshttp://www.qsl.net/kc4gzx/kc4gzx/project20.htmCircuit tracer (neither of these would not load 4-3-09 kept getting message "the Connection was reset."):should have schematic:http://circuitos.tripod.cl/schem/r111.gifand the signal generator:http://circuitos.tripod.cl/schem/r25.gifA little paranoid voice thinks this Instructable has some clues to the solution: How to prevent thefts steal your motorcycle for less than US$ 2 Thank-you in advance,

Topic by Jonque    |  last reply


Lost latest edits and revert is not working

My most recently saved version turned the step into garbage, and when I attempt to use the revert feature I get a pink box saying "sorry there was an unexpected problem". Regardless of which previous versions I attempt to rever to I get the same response. I thought perhaps there was something wrong with the website, but It's now been over 12 hours, and the response doesn't change. Could someone please tell me how to solve this?

Question by edmark    |  last reply


Can i mix fiberglass with clay to make it stronger?

After a decent search, i haven't come up with much.  So, does anyone know if i can put fiberglass into clay to make it stronger after firing? or would it re-melt into a bunch of tiny glass rods with no structural integrity?

Question by kretzlord    |  last reply


V-Gate Motor, what is fake, what is real, why is it not possible

If we look at so called magnet motors than they usually share the common works of a V-Gate somewhere.So with the energy crisis blooming it might make sense to take a look on how these fance toys are supposed to work, or not work.You can check Wikipedia and watch a lot of Youtube videos showing magnet motors or just V-Gate magnet toys in operation.As the name suggests the permanent magnets are placed in a V shape configuration.Either linear or in a circle / on a drum.And the working theory suggests that if you place one or two magnets at the right spot in relation to the V than forces will make things move.It is great fun to play with a V-Gate just to figure out how the magnets actually interact.The longer you play with it and experiment the closer you think you are to actually make it work.No matter what you try though there is always a spot or an area where the magnet do the exact opposit of what they are supposed to do, the bind instead of making things move.Especially in the videos you can see a lot of interesting ways trying to compensate for this or to fool you.And the thing really no one wants you to know is that the pushing forces you want actually reverse half way through the cycle.But at this point their forces are already quite low.Would make sense now to just use that part of the V that actually works and to repeat it, doesn't it?If you do then you always end up with the same as what you had before, just more sections of it ;)And since in nature everything is equal we can not make the unwanted forces disappear and only keep the ones we want.Or can we? ;)A flywheel is a good option to preserve energy and to store it.No wonder then that people like to go big and include as many magnets on the drum as possible, preferably big and heavy as well...And since we can see in some videos that you can even make it spin by moving the magnet bar by hand: How hard can it be to do it properly?A flywheel needs energy to get going, especially if heavy...If the system would have the energy to make this spin then for obvious reasons it would only get faster and faster - but none of these toys do this...And well, moving your hand requires energy too ;)But combined with a mechanical or magnetic link it shall work just fine, timing is everything...And so you keep going and trying and in reality get nowhere at all.As said, you can't have only positive forces without the corresponding negative force(s).Modern approaches to the problem....The famous Yildiz generator uses all sorts of tricks.For example electromagnets to cancel out the field of permanent magnets, powered by internal generator coils of course.Or shielding around some magnets to direct the magnetic field in other directions.Others try to use a different angle for the magnets so seemingly one side of the field is stronger than the other.And the real enthusiast even machine their own magnet shapes from block magnets to get the field lines where they want them to be.In some case you can even find claims of commercial products in operation, with a convient link to order you own on a long term contract.This seems to suggest that there is indeed a way to create at least electricity for "free"....Of course this only made more plausible by the "security packets" included with these lease agreements.Sealed units, 24/7 remote camera surveillance, online connection for remote monitoring and on the go adjustments....And, no without the constant feedback from base operations through the online connection the "generators" will just stop.In a way all this only makes the search for the holy grail of magnetism more interesting.Just consider this:If it is worth to waste god knows how much money to create elaborate fakes with supporting websites and articles seeded all over the net, then why is it worth it?A real money scam would be exposed quite quickly and the websited disappear with the business.And if it is a real and registered business then they have to make the money somehow in legal ways.A balanced approach to the realities and options to make V-gate motor/generator as a workable toy....We know we can cheat and we know we can use modern materials.To make an interesting toy we would need to make it look and work interesting.Just a moving drum is boring and prone to be called a fake right away.Some fancy lever moving the magnet bar is nice but already well too abused to pass.Gearboxes and cranks however are not used that often due to the complexity of creating them in your garage.And some mechancial master creation displayed in museums of other places as "perpetual" motion machines are insanely complex.It comes down to first mapping the areas of negative impact, then finding ways to compensate for them.Preferably in some fancy optical way.Like the magician uses slide of hand to fool you you distract the audience by providing them things to focus on.The more focus on the workings behind it all the more they forget to understand physics ;)For example: If you want to lift the magnet bar you can use a fancy looking crank wheel that is overbalanced for the binding forced of the magnets - fools the unsuspecting person to think you actually eliminated the forces while in reality the wrong balance causes a problem later in the spin.And for those who were able to fllow that trail correctly you have something like and additional magnet moving to compensate fr this wrong balance.....Just make sure you seemingly complete the circle of force elimination back to where it started ;)Mumetal...Not, it does not come a cow....And yes, it is a real thing and not a fancy make up free energy freaks created ;)Unlike normal steel or iron Mumetal is extremely good in directing magnetic fields.For example the positioning head of your hard drive uses a pair of magnets on Mumetal plates to make sure the close proximity won't affect the disks storing your data.Now, some people on the net use these features to really fool you badly when it comes to magnets.From magnets in loudspeakers they misuse the term "shielded" to state Mumetal actuall shield the field of a permanent magnet.True is only that Mumetal provides pathway for the magnetic field that is thausands of times easier to follow than air.For example:A strong manget that still creates a noticable field at let's say 3cm distance.A Mumetal of 4cm in diameter placed 1cm apart would make the affects of the magnetic field disappear at 3cm.But not because the field is shielded, because the magnetic field lines now have an easy way to follow.They just "can't be bothered" anymore to go around the plate.In terms of utilising these effects for a V-Gate toy we can get really creative indeed.Some classic V-Gates use a magnet facing north on one side and a magnet facing south on the other side of the magnet bar and drum (left,right).Proving a Mumetal strip between them increases the field strenght on the other side quite a bit.It also allows for a much smaller extension of the field to the sides.And whatever area is covered by Mumetal will not show such a strong field, or none at all.So it would make sense to create a fancy gearbox to rotate a magnet bar.With every set of magnets on the drum the magnet bar makes one rotation.Like a real DV motor so to say.While the magnets attract each other the "active" side is exposed, and when the point comes where they would start to bind the "shielded" side is exposed to the drum.And like with all good mechnical toys we would have to find a way to revers the rotationthree times during one rotation of the drum to "compensate" for the reverse changes with a magnet bar that has a fixed spacing.Pushing instead of lifting....If two mangnets are used for the magnet bar it becomes obvious that a lot of "force" goes sideways instead of being used to actually push the drum.Hence the V shape to fool you the shape actually makes pushing possible to start with.Now read carefully and try to follow so you are not getting fooled by the explanation how to fool other people:For get an even base of understanding I will start where the closed end and the open end of the V meet on the drum, right where the pushing action starts.If the distance of the bar magnets dicreses with the V shape than we get even pushing forces working for us without the problem of reversal half way through the rotation.However we do get insane binding forces right when we get back to the start point of our rotation.Here we flip the magnet bar one full turn while the drum moves from pushing to pulling/binding.The direction of this rotation is important as it needs to match what the drum does.At the point of half rotation of the bar the single magnets move outwards again to be back in the start position once the rotation is complete.Complex mechanics, I know...The good thing is that you can always claim you get the energy for the action from the flipping of the magnets and that of course is not done by the mechanis, the magnet bar is flipped by the interaction of the magnets on the drum when the cycle repeats and drives the mechanics due the the inertia of the drum ;)So, is it possible to make it work without cheating and fooling?Sure it is.All you need to do is close the loop and make sure there is always more energy going into moving the drum than stopping it ;)Of course things would be much easier if you would find a material that actually blocks a magnetic field similar to what an opposing field would do but without the involved repelling forces.Like sunglasses for magnetic fields so to say.

Topic by Downunder35m  


New kind of SLS 3d Printer (german)

Hallo Community, ich habe die Idee für einen neuen 3d Drucker, der mit einer Laserdruckerkartusche arbeitet und ein Stützmaterial verwendet, das Streufähig ist.Gerne sende ich mein Dokumentationsentwurf (derzeit rd 13 Seiten) Interessierten zu. Sie trägt folgenden Titel:Die Additive Fertigungfür Metalle und Kunststoffe in Klein- und Mittelständigen Unternehmen für den Werkstattbereich- Aussicht auf ein Neues Verfahren -„ Leonardo Da Vinci und Nikola Tesla waren für mich die größten Erfinder, was würden Sie mit unserem heutigen Wissen für technische Wunder vollbringen?“ Hat jemand interesse sich daran zu beteiligen?

Question by zadouwe    |  last reply


12v brake and tail lights?

I'm trying to build a brake/tail light out of LED's for my motorcycle. How do I make the red brake lights brighter than my red tail lights? I'm using 3mm 12v (resister pre wired by supplier) and/ or have similar 10mm lights available too.

Question by dthing    |  last reply


Which wood would be good for making a crossbow??

I want to make a crossbow, not a proper one one, just a toy one so that I can have some fun. However, I'm not sure which wood would be best for the bendy bow bit. I'm located in England, and I would like an easily accessible wood to make it. 

Question by Crafty Dragon    |  last reply


Direction microphone questions Answered

A few days ago a friend gave me a directional mic he used with his camera.Of course I don't get these things as a working present but to repair them :(Anyway...Taking it apart to expose the inside was the first nightmare as for some reason my friend decided to use a splash proof mic on a totally unprotected cam.If you ever tried to take one of these aquarium tube heaters apart you know what I mean...To my surprise this formerly expensive toy failed due to a bad solder connection, easy to fix.And lucky as well because the actual microphone capsule was glued in place pretty good.A quick test on the computer with the supplied microphone amp showed it worked fine again so I wanted to find out how it actually works.They toy ones use a half sphere or mini dish to reflect the soundwaves onto the mic.My friends however was an aluminium tube of about 20cm lenght.15mm in diameter with the mic being just 5mm and sitting in what seemed to be the end of a little funnel inside the tube - right at the end.So in theory I would now just say the thing gets what comes in from the front, but well that would be far too easy...When I pulled that fluffy sock off the mic I realised two weird things:6 small holes going straight through the mic funnel and outer tube.A glued in relatively soft plastic sleeve with a wave pattern.It seemed this pattern changed on the way down but I could not really see inside properly.Closing the front hole and the mic had no problems getting all sorts of noise from all directions, quite lower in volume compared to a direct hit from the front though.Closing the small side holes with some tape and the mic is still very directional but also really noisy.It seems some acoustic magic is happening in the tube.No real clue though but I guess the sleeve acts like the sound dampening in a test room.Without it all sound entering the tube would reach the mic, while with it really only a very tiny, front facing angle is able to reach the mic.The aluminium certainly transmits some sound onto the mic and the glue appeared to be rock hard as well.So I have to assume that the sound entering through the tiny holes somehow cancels out the noise transmitted by the tube itself.With just 15mm in diameter however I can calculate what I want but am unable to get any true 180° phase shift happening.Looking up how other types of directional microphones work was a bit helpful here but not so much in understanding the holes and liner.My friend said it is well over 30 years old and that he got dirt cheap at a garage sale.No markings anywhere and the small amp only has the connectors for mic, power and output.Did not check the circuit board inside as the housing was glued together.So:Why holes in the side right at the height of the mic?Why does it "hear" all surrounding sound when the front is closed but only directional with the front open?And I mean directional even with some music playing close the mic :(By the way: Battery pack for the mic was the classic four pack at 6 Volt.

Question by Downunder35m    |  last reply


Is it possible to use router bits (6.4mm) for rotary?? Answered

Hey guys my first time post here:3 As you can read from this topic, is it possible to use router bits(6.4mm) in rotary?? like using extension collet or something?? I found some information on the internet that it is not good idea to do so considering the power and so on, however I would like to know if there is any way that to make it possible to save some monet.... thank you

Question by diydaiku    |  last reply


Is it possible to use router bits (6.4mm) for rotary??

Hey guys my first time post here:3 As you can read from this topic, is it possible to use router bits(6.4mm) in rotary?? like using extension collet or something?? I found some information on the internet that it is not good idea to do so considering the power and so on, however I would like to know if there is any way that to make it possible to save some monet.... thank you

Topic by diydaiku  


Simple solution to prevent load swinging in overhead crane

Cranes are used to move loads from one location to another in minimum time such that the load reaches its destination without swinging. As we all know, that swinging problem occurs due to flexibility of wires but if the wire is rigid and permanently fixed on one side then ???As per the sketch there will be a telescopic arm and one side of the arm will be attached with the trolley of the crane. This rigid telescopic arm will be connected with the load at the time of lifting the load. In this way there will be no problem of swinging as the rigid telescopic arm will be fixed with the trolley and wires will work to lift the load so there is no chance of swinging of load.My solution can achieve these following points at the time of construction.Improved Safety High-Precision Moves Increased ProductivityEasily Implemented on Existing tech Save time Save energy to reduce carbon Cost as the crane can work at the time of high speed air. My solution is simple, low cost and very effective to prevent load swinging problem.

Topic by vikram_gupta11    |  last reply


Car Battery

When I tried to start my  car the ignition just clicked a few times, then finally started.  It seemed like the battery was weak.  I spoke to a mechanic who said probably one battery cell was bad and advised that I replace the battery.  I did that and now have a brand new battery. I didn't fix the problem.  Does anyone have advice?

Topic by BdaSpidey    |  last reply


Alternative Nuclear energy

p.MsoNormal, li.MsoNormal, div.MsoNormal { margin-top: 0.0in; margin-right: 0.0in; margin-bottom: 10.0pt; margin-left: 0.0in; line-height: 115.0%; font-size: 11.0pt; font-family: Calibri , sans-serif; } p.MsoHeader, li.MsoHeader, div.MsoHeader { margin: 0.0in; font-size: 11.0pt; font-family: Calibri , sans-serif; } p.MsoFooter, li.MsoFooter, div.MsoFooter { margin: 0.0in; font-size: 11.0pt; font-family: Calibri , sans-serif; } p.MsoListParagraph, li.MsoListParagraph, div.MsoListParagraph { margin-top: 0.0in; margin-right: 0.0in; margin-bottom: 10.0pt; margin-left: 0.5in; line-height: 115.0%; font-size: 11.0pt; font-family: Calibri , sans-serif; } p.MsoListParagraphCxSpFirst, li.MsoListParagraphCxSpFirst, div.MsoListParagraphCxSpFirst { margin-top: 0.0in; margin-right: 0.0in; margin-bottom: 0.0in; margin-left: 0.5in; line-height: 115.0%; font-size: 11.0pt; font-family: Calibri , sans-serif; } p.MsoListParagraphCxSpMiddle, li.MsoListParagraphCxSpMiddle, div.MsoListParagraphCxSpMiddle { margin-top: 0.0in; margin-right: 0.0in; margin-bottom: 0.0in; margin-left: 0.5in; line-height: 115.0%; font-size: 11.0pt; font-family: Calibri , sans-serif; } p.MsoListParagraphCxSpLast, li.MsoListParagraphCxSpLast, div.MsoListParagraphCxSpLast { margin-top: 0.0in; margin-right: 0.0in; margin-bottom: 10.0pt; margin-left: 0.5in; line-height: 115.0%; font-size: 11.0pt; font-family: Calibri , sans-serif; } span.HeaderChar { } span.FooterChar { } *.MsoChpDefault { } *.MsoPapDefault { margin-bottom: 10.0pt; line-height: 115.0%; } div.WordSection1 { page: WordSection1; }   Alternative  Nuclear energy. Our main source of  energy right now is nuclear energy. Although Nuclear energy  might seem to be a reliable source of energy, it is not.  Nuclear energy is not a reliable source of energy  because you need to extract Uranium ore from the earth's core which might seem as a good  source of Uranium it is not. This is not a endless supply  of uranium because it will eventually  run out of uranium .   So what can we do to solve this issue? The answer is alternative energy.  Alternative energy  is energy that can be renewed  and that is reliable. One solution is replacing Uranium fuel rods in a reactors core with Tritium. Tritium can be used  as a substitute for uranium because it has the same properties as uranium except that it has a shorter  half life.  Tritium is made by fusing solid  Hydrogen With Lithium  in a Farnsworth reactor.  This also has its problems one major  problem is the radiation and heat that is generated during the process  of fusion. Tritium can be then used as a fuel  pellet for a Nuclear reactor when it is mixed with Deuterium which is a solid. Tritium is also a good fuel pellet because it only has a life span of about 12.4 years, then  it decays into Helium 6 which is very harmless. Uranium on the other hand is not  safe because it has a life span of about 2000 years and it gradually decays into other radioactive material such as Thorium, neptunium, ECT.... This is Called the Uranium - Thorium cycle. The tritium is also ecologically friendly because it  can be made from H1 which is found in water H2O.  H1 is called Portion and is extracted through a process called electrolyses in which water is charged by a D.C current.

Topic by dciocoiu    |  last reply


How can i connect my car stereo to powered speakers?

I have a pair of edifier R1280t powered bookshelf speakers which sound great. They have two inputs and i use one of them with my pc. I have a car stereo lying around and would want to hook them to the other input on the speakers using a psu. But my question is, can i connect powered bookshelf speakers to my car stereo? I have rca connections on the stereo and i think i can connect them but i am not sure. Please help me. Attached is the stereo wiring diagram in the manual.

Question by Mohanponnam    |  last reply


Energy efficient, waterless, Copper strip based cooling system

Energy efficient ,waterless Copper stripe based cooling system:The presented Idea is based on Heat exchange principle.As per sketch there will be a conveyor belt system and some copper stripes will be connected with this belt.Each copper strip will have a moveable hook.The conveyor belt will move with a motor.Each copper strip will be separated with each other and with conveyor belt with the help of Insulation (wooden insulation).Each copper strip will be connected with the machine for 15 to 20 seconds to absorb the heat and after that this copper strip will be removed and next copper strip will be ready to absorb the heat.The removed strip will be cooled down after some time and will be ready to couple with the machine again.In this way each copper stripe will work one by one to absorb the heat to cool the machine and each strip will get cool down due to convection .What I thought is that if I use a continuous water jet to cool the motor then the motor will remain cool so if I use the copper stripes then the same effect will be occured.It will work in this way that temperature will be not increased of machine if I couple the device with the machine. It will be low cost,low maintenance,waterless solution to cool the machines. It will consume almost nil energy

Topic by vikram_gupta11    |  last reply


Rust on sink drain pipe

HI,I have noticed this year that the exposed drain pipe from my bathroom sink is rusting badly, turned all green. Why is this happening? Anything I can do about this? I guess I should replace the pipe, but this will be complicated cause it is going into the tile floor and the cent under it. Any advice would be welcome.Thanks

Question by Veters    |  last reply


How to make a vacuum cleaner battery powered? (Luigi's Mansion Poltergust project)

I'm thinking about making a functional Poltergust 3000 from Luigi's Mansion. The end result would basically be a back-mounted rechargeable vacuum cleaner with a toggle switch on the nozzle for at least "off" and "suck", although adding a "blow" option would be ideal to replicate as much of the functionality of the Poltergust as possible. The problem here is that I know very little about electrical work outside of basic on-off light circuits.How do I figure out what kind of power source I'd need? I'd be buying a new vacuum for this project so it should have the tolerances listed in its manual, but I also have a multimeter handy for finding specific values. Also, if I am to add a "blow" option, would it be a bad idea to try and run the motor backwards so air blows out the nozzle? Finally, how could I make it's power supply rechargeable? Ideally I want for it to be able to charge up in a conventional wall socket.

Question by Chops_McCartney    |  last reply


Ca huge drinking water filtration system be modified for a fish tank?

I got a few of these filtration units:For drinking usage far too big but I was wondering if it would be possible to modify parts of it for filtering the water in my aquarium.Inside the black canisters is a prefilter (big one) and a de-scaler cartridge (small one).As they are independent from the quad filter system it only leaves the question of modifying some pipe for the inserts and finding a suitable filter medium.Would be nice as a pre-filter to keep the worst crap out of the filter pump.

Topic by Downunder35m    |  last reply


Switching to LED lights for your car head lights - what you should know about it!

With LED technology getting cheaper and better almost weekly now it seems to make sense to use them in your old car.People who did it and post about it make the decisions even easier.I mean who wouldn't want to switch from pale yellow candle light to these bright white litghts showing you all in great detail?Problem is the firstly the legal side of things.Many countries now allow the use of LED replacements for many older cars - within limits.Where and if allowed it means you need to use LED systems that a compliant with your local road authorities and regulations.In a lot of countries though it is still not legal to replace incandescent head lights with LED ones.Why is this?If you read this after changing over already you will have noticed a destinct difference between the two types of "globes".The filament is very compact and in a H4 lamp the reflector is quite small and perfectly positioned as well.In comparison to (mostly the non-legal) LED replacements the light emitting surface is flat and usually a lot bigger than the filament.This means the light output and pattern changes as the reflector of your lamp is not designed to work with LED's and their bigger area of light surface.Being flat also means the LED can not really produce the same amount of light in LUX to the sides as compared to directly above.Most LED lamps compensate this with an added reflector in the front area.So we have two major problems:Not really enough light going sideways while too much light goes up and down in the LED system.Too much stray light due to the bigger surface are that puts out the light.Combined they result in light going into areas where it should not go, or not go at this level of brightness.The often used statement that now even highway signs are easy to read at night on low beam clearly highlights this problem.There is a good reason your head lamps should not shine upwards ;)What can be done to allow for the use of LED lamps in old cars?If not too old than your car already has H1/H7 lamps and indiviual for fog, low- and high- beam.For those it is now quite easy to get road legal LED replacements.Not so much though for the really old H4 systems with high- and low- beam in one lamp.Don't be fooled by your local auto shop though!Just because they might sell a lot of HID and LED lmaps does not mean what is on display for sale is actually road legal.If it does not state the corresponding certifications for your country/state than you can rest assured a cop on a bad day will have field day (or night) with you sooner or later.As said, in many countries there are now tested and legal option available.Their main difference to the cheap and uncertified ones is not their higher price alone.In comparison their more powerful LED's result in much smaller COBS -the LED strip giving the light.Reducing glare and providing a much closer match to the incanscent lamps.Why is it so hard to find a common ground and provide proper LED replacement systems?You might as well ask why you can buy a $20 amplifier or a $5.000 amplifier....When the first cars came out with LED lamps China saw the potential and provided all sorts of headlight lamps with LED's in them.Quickly they not only made it to the international markets but also gained interest for basically everyone wanting more light.Regulations were non existent back then...Even today it is next to impossible to actually provide proper numbers in terms of lumen, LUX or general brightness.What a LED provides can be quite different from what leaves the head lights.Old standards only refer to Watt, so it is no problem to find a cheap LED system that provides what a 100W lamp would get you at less than 30W on the input side...And the light color is not really specified at all in most countires.France required a yellowish light back in the day.A blue tint in your head lights was no problem with Xenon lights, so LED systems now go as high 7000 Kelvin, or close to a blueish light and as low as 3000 Kelvin or what is coming from incandescent lights.You see, finding a common ground is already hard just with the light output and color alone.There is only one real test that even today defines whether or not a head light needs adjustment or in case of LED replacements makes them illegal.The good old white wall with the markers, lines and distance mark on the floor.If you compare a properly adjusted head light on these test walls you get a very destinct pattern of light to see.Clear cut off's, brightly illuminated areas within the fields and lines and less bright areas in the outer regions - again still defined by the marks on the wall.Swapping to various types of LED replacements should provide the same patterns and brightness levels.In reality though almost all of them will only give you a very bright and undefined big area on the wall.No more dark areas with clear cut off to the bright middle section, even the formerly shadowish side areas are now well lit up.Great for you behind the wheel, bad for everyone coming the other direction, especially when wet and raining.Some people in the colder parts of the world will now what I mean when I say that some LED system will only give you good visibility when it snows if you turn them off ;)How to check for yourself if your new LED lights are any good for other people on the road?I assume you did the right thing and had your headlights checked and if required adjusted before actually putting LED lights in!Nothing is worse than trying to get more light if said lights are adjusted to point everywhere except the road.With your old light still in park in front on a straight wall on level ground, like your garage or any other wall you find.Park at a nice distance to get a clean pattern on the wall that is not too big.5 to 10 meters away should do fine.Use some painters tape or similar to mark out your desgined light pattern on the wall.Don't be too fancy, just some tape to indicate where bright light turn into way less on the wall and a few strips to indicate the cut off lines where patterns of brightness change on the wall.Leave the car where it is and put your new LED lights in.Check for yourself by how much the areas differ now.Anything above your marked cut off lines means you are blinding other drivers ahead of you.Anything way brighter than before on the sides could mean you also blind oncoming traffic on the other side of the road or freeway.A pale and low light level in these areas is not too bad and can be acceptable.Anything that clearly illuminates those formerly dark areas however should not be used on the roads.Another check is to try at what distance your old low- and high- beam start to become a bit too birght too directly look in to when you stand in front of your car during a really dark night.Look somwhere drak and move closer until you reach the discomfort zone.With your LED lights you should be able to get as close as before ...

Topic by Downunder35m  


Sears 10" Radial Saw Parts

I have a Sears 10" Radial saw that I purchased in the late 60s. Serviced me well for many years as a cutoff saw. It now does not want to run. It starts, comes up to speed and runs for about 30 sec. with no load and then shuts down. I wait a couple of minutes and reset the protector, repeat, same results. I would love to continue to use this saw. Do you have any idea where I can get replacement parts or equivalent parts? Model # 113.29440 Protector 37408 Relay 30588 Capacitor 30586

Topic by dggeiser  


Attaching a Spur Gear onto a Motor

I want to attach a spur gear with a bore diameter of 6mm onto the shaft of this motor (6mm diameter shaft). How would I go about doing this? From what I see, the shaft is smooth so is my only option to find a gear with a set screw? Or is it sufficient to attach a gear with no set screw and simply rely on the friction of the bore? The torques will be low. Are there any websites that one would recommend for finding gears like this? I'm finding it impossible to find gears with a module of 1.0, bore diam. of 6mm, 12 teeth, and a thickness of less than 20mm to fit onto the shaft.Any help would be greatly appreciated.

Question by Pndlm    |  last reply


Refurbishing machine components

If you are in the maintenance and repair business job wise, then quite often comes the question:Buy a new replacement or refurbish the broken part.In many cases it simply makes so sense to refurbish as there is no time to do this sort of work.However, once replaced you are left with a part that might only have a minor defect that is supposed to go in the bin.Quite annoying if we talk about costs in excess of $400 for those parts.When it comes to electronics it can be as simple as a blow fuse that is hidden inside a controller or a cheap varistor, relay or such.For example, we had big issues with failing control panels.The most used button simply did not make a contact anymore - $2000 a hit to replace.With the faulty ones piling up I decided to have a look.20 bucks later for some tiny push buttons and a bit of soldering all up $12.000 were saved for future panels.Another good was a drive assembly for a valve.Over $500 for one and it turned out the only thing that really failed was a $15 DC motor of the 555 type.Well, and about a spoon full of grease to lube the gearbox again.Back in my younger years there were lots of companies offering refurbished and tested spare parts for machines.Now this seems to be reduced to car wreckers only and even there you often struggle now due to the recycling crisis.Are we really already that far advanced that it is no longer financially viable to repair things in other ways then by replacing them?All those costs cut the profits and with that either increase prices or reduce hours of work.Recycling is reduced to exporting our waste or sending it all to landfill sites.Is that really the future we want to leave for our kids?

Topic by Downunder35m