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If you've ever assembled a piece of flapack furniture, you've probably encountered a 'cam lock nut'  though you may not have heard/read that term. The challenge is to model one. 15mm dia. x 12/13mm deep; with the spigot that the cam acts on measuring 6mm dia. x 8mm long with a 4mm shaft. Warning. This is not trivial. I have not found either an existing model, nor engineering drawings, so its a bit hit and miss..  

This set of questions stems from footnotes I've seen on data sheets for blue or white LEDs. One is a footnote seen sometimes on the Reverse Voltage specification: Note: Reverse Voltage can't be continued operating Another I've seen on the graph of luminous intensity vs forward voltage, recommending against operation below a certain forward voltage. These footnotes are easily overlooked if one isn't reading the data sheet closely.So my questions for an expert in LEDs:What are the reasons behind these warnings? What I do know:I realize that spectral response can vary with applied forward voltage, so might not meet the data sheet specs at low Vf. But are there other consequences behind the warning against operation below a certain forward voltage? As far as the reverse voltage warning, I remember when blue LEDs first came out hearing that they were more easily damaged electrically than previous LED types. But I'm not sure whether to interpret the warning I quoted from the data sheet as an admonition to be very careful to avoid anything over the 5V Vr at which the leakage is 10 uA, or whether there is some slow incremental damage issue even at voltages below the 5V Vr spec in the data sheet. There are common circuits where two LEDs are wired back-to-back, so the polarity of the applied voltage determines which of the two LEDs gets lit. Are these a no-no with blue or white LEDs if you are concerned about long term reliability? Or does the presence of the opposite-polarity LED insuring the reverse voltage applied to the other LED doesn't exceed 3 volts keep it low enough to avoid damage from the reverse voltage? I had assumed the latter until I noticed the data sheet footnote.I note there are a few 2-lead bipolar LEDs with blue as one of the two colors available. I don't know if those have any special formulation or protection.I did some web searching on these issues, but couldn't find much authoritative in plain practical language. I'd love to hear some input from an expert, so I can better understand and protect against the underlying issues.

In my innovation I am getting 10watts of power only from 3 watts. 

Hi, I used altium designer before ,but have problem on DS, Connection hint not disappear when I use copper connet to each other, how to setting this hint ? Thanks a lot

Just want to get the software working, before chatting

How to design a cylindrical structure over a cylindrical structure like joining a pipe over a pipe perpendicularly? 

The kiosk has a 250amp Circuit breaker. It's 25m away from the DB. From the DB to Machine it's 80m the machine has a load of 160AMps. How do I calculate cable sizes for both?

HelloI have made a designspark model and I wanna combine it with a Stl model.I open my rsdoc model, then open the stl model, convert the stl to solid....... and what then.?Can someon walk me through how todo this.??

Hopefully this is a simple one ~ I've created a new version of a component by copying an existing one. But every change I make in the new component is duplicated in the old one. How do I separate the two? Thanks.

Hi,  In older generations of DesignSparkPCB, I was able to draw a board without a schematic.  With DS version10, I seem to be required to draw schematic first.  Am I missing a setting?  How can I draw my simple boards without a schematic on version 10?

Hello All, Electronic product compliance is a topic that has baffled me for years. I have spoken to seasoned engineers and reputable test houses, but I have yet to get a definitive answer regarding when it is acceptable to conduct self-certification on electronic products you intend to sell. The requirements for CE directives like EMC seem especially vague and while test houses are more knowledgeable, they are obviously unlikely to suggest anything that does not involve their services in some capacity which ultimately affects the feasibility of small-scale electronics manufacture. I have heard that observing best-practices and conducting due-diligence may be enough for the vast majority of low-risk products, so would it be sufficient enough to do this for something simple like a flashlight, and then place a CE sticker on the box? I’ve also noticed you can even buy products that actively state they are not CE marked! It’s clear as mud, so I thought it would be interesting to hear the experiences of anyone who has successfully navigated this process and their policies regarding CE marking, self-certification and when you would actually need certified testing?

Do you think that AI will soon be able to know what ingredients you have in the fridge and the cupboard and workout that it is Tuesday so you don't want to spend a long time preparing food so here are some recipes?

Hi Everyone, Single Pair Ethernet connectors are being introduced into the factory.  The suppliers are saying they are going to revolutionise the smart factory as it means ethernet can go the last few feet to the factory floor. However, I've also heard another expert in the world of connectors say that only a few will actually need ethernet down to the factory floor, when other technologies such as IO-Link are available.   So, my question is...   Will Single Pair Ethernet change the industrial space forever,  or is it just another option for installers to have to cope with?

小学校中学年の自由研究でつくった犬の貯金箱が、初めての設計プロジェクトでした(設計プロジェクトと言えるほどのものではないかもしれませんが(笑))。犬の舌に硬貨をのせると、硬貨の重みでスイッチが入り、喜んでお金を食べてくれる、といったものです。仕組みは単純で、尻尾に見立てた消しゴムをDCモータにとりつけ、それを回転させることで、本体が震え、だんだんと硬貨が飲み込まれていくようなものでした。目には豆電球をつけ、モータとあえて直列に接続することで、豆電球の明暗を常に変化させ、ご飯をもらえて喜んでいるワンちゃんのように見える工夫なんかもしていましたね。   My first design project was a "doggy" piggy bank that I made as a summer science project(summer homework at Japanese elementary school) in the middle grades of elementary school (although it may not have been much of a design project). When you put a coin on the dog's tongue, the weight of the coin triggers a switch and the dog happily eats the money. The mechanism is very simple: a rubber eraser which look like a tail is attached to a DC motor and when the motor is rotated, the dog's body tremble and the coin is gradually swallowed. The bank also have two light bulbs as dog's eyes. By connecting the light bulbs in series with the motor, the light and darkness of the light bulbs would constantly change so it looks like a dog that was happy to receive food.

Back in the mid 80's when I was 13, I attempted to build a Flux Capictor out of stuff my Dad had in the garage.  He was a Security Alarm Engineer at the time and our garage was an Aladins Cave of components and I loved playing with some of it. Of course, I wasn't succesful, but the Movie Back to the Future is probably responsible for my interest in gadgets and technology!   My actual first project was fuse tester, think I still have it somewhere...