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Mostrar mensagens com a etiqueta rocket stove. Mostrar todas as mensagens
Mostrar mensagens com a etiqueta rocket stove. Mostrar todas as mensagens

quinta-feira, 16 de maio de 2019

3 em 1 diferente! E magnetizar e desmagnetizar, soldar PLA, Carvão dum Rocket Stove, desenhar e passar à fresa, e Mosaicos automáticos!

Aqui está uma máquina bem intrigante, com um mecanismo diferente, que eles dizem ser mais rápido e seguro, e parece mesmo ser assim...

E ainda vem com 3 meios de ser usada;

  • Como Impressora 3D
  • Como gravadora de Alumínio
  • Como fresa de plástico
É bom!







3D printer SkyOne 
3dlaboratorio 
Industrial 3D printer SkyOne is meant for printing by up-to-date plastics with melting temperature up to 260 °С. Fused deposition modeling technology (layer-by-layer formation of an object from as fused plastic) is behind a concept of its operation. The printer is realized according a coupled design SCARA (Selective Compliance Assembly Robot Arm), two motors control levers, which move an extruder in XY plane. Feeding along the Z axis is realized by a ballscrew transmission. Scheme SCARA provides an advantage in printing speed over printers, which use Cartesian ordinates. But at the same time the software for 3D printer SkyOne is much more complicated than for printers constructed according a standard design. 
https://3dlaboratorio.es/eng/3d-printers.htm










Às vezes, é mesmo útil ter uma ferramenta ou um parafuso magnetizados...
Outras vezes, é bem chato, só atrapalha!

Pois aqui aprendem como tanto magnetizar, como a fazer o contrário, desmagnetizar, e é um instructable bem porreiro:







Tool Demagnetizer and Magnetizer
tonyfoale 
Tools sometimes get magnetised, this can be both useful and undesirable depending on the type of tool and the actual job that you want to use it for. For example there are times when having a magnetised screw driver is helpful to hold a screw when you need to put it in an awkward place but unless you want to do that it can be a disadvantage because it will attract any ferrous swarf, nails and screws nearby. Drill bits are a tools which you would not want to ever be magnetised, it will get covered in chips when drilling ferrous material.
That said, we can see that a means to magnetise and demagnetise tools and other objects like vernier calipers would be a useful workshop addition. To magnetise a tool we only need subject it to a strong uni-directional magnetic field and to demagnetise we subject the object to an alternating magnetic field.

https://www.instructables.com/id/Tool-Demagnetizer-and-Magnetizer/













Para montarem as vossas Engenhocas em secções separadas, e juntá-las, sem cola, ou também para repararem uma Impressão com falhas, podem usar este belo deste método, a soldagem por Fricção!
Algo, portanto, que vos vai poupar a muita re-impressão maçuda...
E parmite ainda uma Engenhoca em várias partes! 









PLA Welding – How to Fuse PLA Seams and Cracks

Tian Ooi  
PLA welding is a way to fill in gaps or “glue” 3D prints together.
Using a power drill with a small piece of PLA filament instead of a drill bit, the rotating filament is pushed against the 3D printed plastic. This generates friction, which heats up the filament and softens it. The filament is then free to fill in a crack or weld plastic together. After cooling, this creates a strong bond, as if it had been part of the piece all along. 
Inspired by friction welding, a welding technique typically used to fuse metals, PLA welding applies the concept of utilizing rotational friction to plastics instead. Friction welding is often used in industry to join dissimilar materials at more stable temperatures than other welding methods. Applications include the aerospace and automotive sector, joining together turbine shafts, car frames, and more. 











Algo de bem ùtil, fabricarem o vosso próprio Carvão, a partir do super-económico Rocket Stove, que aproveita TUDO duma Combustão, o Comcustível, os Gases, as partículas, tudo!








Charcoal RetortKuzmanic
I have had a couple of attempts making charcoal using 44 gallon drums and they have worked okay, but needing a new project after buying a mig welder, I decided to make a retort.
The theory of a retort is that you heat the wood to be made into charcoal up to a point where it starts expelling all of the wood gas and impurities, which is then fed back into the fire to keep the process going.
After reading up and watching a number of videos on rocket stoves and retorts, I decided to make one with the idea of combining the two into one rocket stove powered charcoal retort.
https://www.instructables.com/id/Charcoal-Retort/













Se já têem o Fusion 360, podem idealizar algo, e passar à Fresa CNC, porque o programa tem essa funcionalidade, e aqui está como lá chegar, com um exemplo simpes:






Creating a Simple 3D Model on Fusion 360 and Creating a Toolpath MYDIYCNC 
Tory MYDIYCNC 
Hello there,
Tory at MyDIYCNC here. Today I want to show you how to use a very useful piece of software from Autodesk called: Fusion 360. With this software you can create simple 3D Models, to elaborate and complex 3D models.
What I hope to teach you today is how to create a simple model on Fusion 360, and then create a tool path in which you can then run the G Code on your MyDIYCNC machine or another CNC machine.
Let's get started! 
https://www.instructables.com/id/Creating-A-Simple-3D-Model-on-Fusion-360-and-Creat/











Para algo como desenhos repetivivos, cá está como fabricarem as vossas texturas ou mesmo Mosaicos, Grades, etc a partir duma App na Net:




[STUFF] Polygonia Design Suite
All3DP  
Offering possibly the simplest way to sketch repeating geometric patterns, this browser-based web app is a surefire resource for intricate 2D designs.
We’re not ones for lattice room dividers, but after spending some time toying around with Polygonia Design Suite, it’s just a matter of time before the All3DP office is a maze of fancy laser cut obstacles. A browser-based vector drawing tool for quickly creating geometric patterns, Polygonia is the result of a visit to the Smithsonian and a smattering of high school math and software engineering by its creator, David Kaufman.
Through the simple UI of an online design app, you can sketch out simple line inputs which get instantly translated into rad looking tiled designs. Multiple parameters allow you to customize the design to suit your project and a variety of output formats including SVG and PNG give flexibility for further design software you use after. 







sexta-feira, 17 de novembro de 2017

Fritzing! E mais um Torno Gingery, Wi-Fi à medida, um Rocket Stove, e um Carregador Portátil

Montar circuitos electrónicos como se fosse um Jogo de Computador!

E ainda tem 3 esquemas de visualização, um, como se montassem um circuito numa Breadboard, outro com a tradicional visão esquemática, e outro inda, que permite levarem esse esquema para imprimir um Circuito numa Placa feita à medida para isso!
 
Querem mais?
Vem com vários circuitos já feitos, tanto a nível de iniciado, com o mais avançado...
Impecável.







Fritzing
Fritzing is an open-source hardware initiative that makes electronics accessible as a creative material for anyone. We offer a software tool, a community website and services in the spirit of Processing and Arduino, fostering a creative ecosystem that allows users to document their prototypes, share them with others, teach electronics in a classroom, and layout and manufacture professional pcbs.

http://fritzing.org/home/










Perdoem a insistência, mas um Torno quase de graça, e feito como um Hobby, é muito importante para um Engenhocas, tanto para obter um Torno...
Como para aprenderem como fazer uma Máquina, e qualquer outra, a partir daí!
Aprendam:






Build Your Own (metalworking) Lathe - Part I
corradini

You can make an entire machine shop worth of power machine tools, using basic hardware store/home center supplies and scrap metal. Melt aluminum in a metal-pail furnace, using sand, charcoal, and a clay flowerpot! Cast sophisticated metal tool parts using supplies from a gardening shop and modified kitty litter! End up with a full machine-shop lathe ("the only tool capable of making any OTHER machine-shop tool, including itself!") for just the cost of your time, some scrap steel and aluminum, and a motor!

https://www.instructables.com/id/Build-Your-Own-metalworking-Lathe---Part-I/














Mais numa coisa bastante útil para fazerem com as vossas Impressoras 3D!
Com isto, vão ter Wi-Fi por toda a casa, e o que é melhor, como vocês queiram, nos quartos que queiram:
 






Customizing Indoor Wireless Coverage via 3D-Fabricated Reflectors
Abstract

Judicious control of indoor wireless coverage is crucial in built environments. It enhances signal reception, reduces harmful interference, and raises the barrier for malicious attackers. Existing methods are either costly, vulnerable to attacks, or hard to configure. We present a low-cost, secure, and easy-to-configure approach that uses an easily-accessible, 3D-fabricated reflector to customize wireless coverage. With input on coarse-grained environment setting and preferred coverage (e.g., areas with signals to be strengthened or weakened), the system computes an optimized reflector shape tailored to the given environment. The user simply 3D prints the reflector and places it around a Wi-Fi access point to realize the target coverage. We conduct experiments to examine the efficacy and limits of optimized reflectors in different indoor settings. Results show that optimized reflectors coexist with a variety of Wi-Fi APs and correctly weaken or enhance signals in target areas by up to 10 or 6 dB, resulting to throughput changes by up to -63.3% or 55.1%.

http://dartnets.cs.dartmouth.edu/wiprint



 





Dizem que este Inverno via ser o mais frio dos ùltimos 100 anos!
BRRRRR!
Por isso, é melhor terem este catrapázio no Quintal ou num canto na casa, porque um Rocket Stove;

-Funciona com galhos, cartão, e etc;
-Gasta muito mpouco combustível porque o aproveita até às cinzas;
- Como queima até o fumo, e o monóxido de carbono, é muito mais seguro, mesmo para dentor de casa!
Muito importante.
Atenção, a Introducção é mínima, mas as Instrucções, são muito completas:






Building a Rocket Stove for the Cabin
foodplotsurvival

FPS combines my passion for hunting and wildlife conservation with the overall need for self sufficiency.

https://www.instructables.com/id/The-16-Brick-Rocket-Stove-Quick-30-Second-Build-Ea/









Há Carregadores Portáteis que resultam mais baratos que construír o vosso próprio Carregador, mas se como eu, coleccionam Sucata...
É de graça!
LOL
Por isso, mãos à obra:




 



Build Your Own Inexpensive Powerbank with 3D Printing
Matthew Mensley

Instructables user Nematic! details how to make your own portable powerbank from laptop cells, 3D printing and a little electronics savvy.
We’ve all experienced that unique feeling of helplessness and anguish that only a dead cellphone battery can bring. Cut off from the internet and contact with others it becomes impossible to navigate, and what the heck are you supposed to do while sitting around waiting for the bus/train/plane. It sucks.
Fortunately there’s no shortage of inexpensive power banks knocking around to keep you topped up with juice on your travels. But for the thrifty with time to kill and a handful of old laptop batteries lying around (a common scenario, we know) there’s an alternative.
In a short-and-sweet post over on Instructables, user Nematic! shows us how with nothing more than a few tools (3D printer, soldering iron and glue gun), a cheap powerbank module and some 18650 cells, you can make your own smartphone powerbank lickety-split.

https://all3dp.com/3d-printed-powerbank-how-to/ 







segunda-feira, 14 de agosto de 2017

48 Programas de Impressão 3D! E Oficina Garagem, uma Ventoínha sem pás, medir cantos, e uma Fresa CNC gigante!

A lista mais exaustiva de Programas de Modelagem e Impressão 3D que eu já vi, 48 Programas diferentes!

E podem seleccionar por  3 categorias, Versão grátis, Sem Instalação, e Bom para principiantes.

É bom.








The Best 3D Modeling and 3D CAD Software Tools For 3D Printing

DO YOU WANT TO LEARN HOW TO CREATE GREAT 3D DESIGNS FOR 3D PRINTING?
We've compiled a curated list of all the different design suites out there. The software suites listed on this page are used extensively in the world of 3D printing. Whether you are just starting out with CAD design, or are an experienced designer looking to take things to the next level, you'll find something to suit your needs on this page. Look out for a star to see the software recommended by MyMiniFactory. If there is software you use that is not on the list, please contact us.










Neste Canal do Youtube, 300% Brasileiro, podem aprender uma data de coisas boas, por isso, vão lá, que o bacano sabe da coisa e sabe explicar bem, trabalho de categoria...
Vou ver se faço uns vídeos assim. 

Este em perticular, trata de como construírem este magnífico, embora simples de fazer, Fogão a lenha regulável: 



 





Fogão a Lenha Portátil / Wood Burning Stove - DIY
Oficina Garagem

Nesse vídeo vou mostrar o passo a passo de como fazer um fogão a lenha portátil com baixo custo de fabricação e ótimo custo beneficio, tanto serve para Camping como também para usar na sua casa.
Gastei nesse fogão cerca de 30 reais de materiais, basta você garimpar os ferros no ferro velho ou sobras em alguma serralheria.
Espero que gostem, deixe aquele like bacana e compartilhe com seus amigos nas redes sociais, um grande abraço e um beijo no coração.













Eis com fazerem uma Ventnoínha estilo Dyson, porque está calor cmo sei lá o quê, e assim não levam com o "martelar" tão próprio das Ventoínhas tradicionais...






3D Printed Portable Bladeless Fan
WhyyNot

"A bladeless fan (sometimes called an air multiplier) blows air from a ring with no external blades." Dyson is a very popular company who has utilized this technology to make a quieter fan that performs better than more traditional versions. A common misconception is that "bladeless fans" are not actually bladeless. Instead of being external, a small fan is located in the pedestal and forces air out of a thin ring.
Here I'm building a very basic model which won't perform nearly as well as the Dyson models, but will be a small fraction of the price. This small model is easily portable and can be refreshingly used in a vehicle or outside as well as inside.
Parts printed on a Monoprice Maker Ultimate in PLA with a 0.4mm nozzle on a heated print bed.

https://www.instructables.com/id/3D-Printed-Portable-Bladeless-Fan/














Pode-se agora medir o Raio dos Cantos circulares de algo que queiram reproduzir, ou duplicar, com esta gigajoga impressa em 3D! 
Cortesia da JayconSystems, é perfeita para "reverse Engineering", e conserto, por substítuição, de peças que já não se fabricam mais:







How to Measure a Corner's Radius Using a 3D Printed Tool
JayconSystems

The world is filled with millions of different objects all with different shapes, angles, lengths, heights, widths, surfaces, depths, volumes, geometries, etc… You get the point. There are many different ways of measuring all of these different objects. Here we will focus on measuring rounded corners on physical objects. This can be a difficult task without the right tools.
Our Mechanical Engineering Team at Jaycon Systems creates, reverse engineers, and tests hundreds of hardware projects every year, so in order to make our lives easier, we came up with a simple 3D printed tool to help measure the various radii (believe it or not that is the plural of radius) of the things we work on. We hope we make your life easier as well by making these files available to the public.














Cá temos uma Fresa CNC, mesmo a puxar pró grandinho, que pode estar mesmo a calhar para alguma Oficina de Garagem, por aí...
Um Sonho realizado, para muitos.




Build Big Cnc at Home 3x2m
VladoM

So why this should be of any interest of yours?
This machine was build without any special tools, basicaly drill, clamps, saw and meter would do. Of course there is more, like drill bits or, taps... but i built this one without having even a proper table.
Machine was designed to use as few part as possible and to be as precise and strong as possible, also speed was desirable as i wanted to use it with plasma, then i also wanted to be able take the machine apart, build it from localy available components so no premade table parts are needed to make the build, and after all this this machine still needed to be nice and square. Weight of some components and force distribution was also thought over.
At the end here are some realy interesting solutions for problems i delt with, worth to check out, at least i believe so.













quinta-feira, 19 de fevereiro de 2015

5000 Dólares para o vosso Protótipo!!! E OpenPi, Ponoko, agora, Corta Metal, 10 usos para o VLC, Uma Oficina num só móvel, e um Fogareiro.portátil

Querem 5000 Dólares para construír a vossa Engenhoca, ou o vosso Protótipo?
Concorram, DEPOIS de patentearem a Ideia, a este Concurso da Make, e habilitam-se a ter o Protótipo dos vosso sonhos...
DEPOIS de patentearem a Ideia!




Pitch Your Prototype… And Win $5,000
Jon Christian

Want a chance to win $5,000 and be featured at MakerCon New York this September? If so, consider entering the Pitch Your Prototype contest, a collaboration between Make: and Cornell University with the goal of digging up promising prototypes from the Maker community. Maybe you’ve been working on a wearable, or wrestling with a Raspberry Pi. Regardless, don’t be afraid to put yourself out there by entering—contestants in previous Make: contests have included an aerial film platform, plushies modeled on video game characters and an outrageous four-wheeled bicycle made from recycled materials.









Maquineta fantástica, dica do nosso amigo Fernando Mattoso Lemos, eis uma Ferramenta para os Inventores, que vos permite juntar Controle programável ao que precisem, como queiram, e au um preço bacano!
É bom, ou não?
Até a Microsoft está usando...





Open source design lowers cost by 2/3rds of building Raspberry Pi Compute 1&2 powered cool stuff.
Update : We are adding to the design support for Bluetooth Low Energy
Update : We are adding an IR receiver to OpenPi
Update : Check out OEM and EmonCMS running on OpenPi read more
Update : Microsoft are using OpenPi on Tech Days read more

Wouldn’t it be great to build hardware at the speed or cost of software?
OpenPi is an open source project, and a neat alternative to the Rasberry Pi Compute development kit. The holistic approach for non-embedded engineers, guides people who love to write software, through the problematic stages of getting small scale products to market. On offer are reference PCB’s, a customisable ABS case, open-source design files and collaborative design support. When it’s as easy to get up and running as a games console, and affordable enough for cottage industry inventors to profit from, OpenPi is forging a new way of bringing cool ideas to the masses.










Pois é, podem mandar agora os vossos desenhos para a Ponoko, e recebem em casa as peças cortadas, em Aço, Cobre, ou Bronze!  
Por isso, inscrevam-se e mandem vir as vossas engenhocas 



New! Streamlined Support for Photochemical Machining

Making with metal just got a whole lot easier.

We are thrilled to announce new streamlined support for Photochemical Machining. Previously, if you wanted to create something using Brass, Copper or Stainless Steel, you had to take an extra step to email us the extra details of your order.
Now you can upload PCM design files directly to your Personal Factory account. In addition, you can now upload and get a quote for metal parts along with Laser Cut & 3D Printed designs at the same time, all in one order.
How to make with Photochemical Machining (PCM):
  1. Prepare and save your vector design as a PDF using our Metal Machining Starter Kits.
  2. Upload your PDF to your Personal Factory account.
  3. Select your choice of metal materials and proceed to checkout as usual.
That’s it! You’re now on your way to receiving some awesome metal goodies in your mailbox. Please note: The design requirements for PCM are slightly different from laser cutting with other materials. You’ll want to be sure to read through our design guides before uploading your designs.








Achado através do Stumbleupon, o Site HowToGeek vem-nos ensinar como fazer de tudo um pouco, em Vídeo, com o programa Grátis VLC Media Player!



10 Useful Features Hidden in VLC, The Swiss Army Knife of Media Players

There’s a good chance you already use the VLC media player. But VLC isn’t just a media player — it’s a complete Swiss Army Knife for digital videos and music, filled with useful and fun features you haven’t found yet.
If you’re just using VLC to play back local media files, you’re only using a tiny fraction of VLC’s capabilities. There’s so much more you can do with VLC, whether you’re using it on Windows, Mac, or Linux.








E só porque sim, cá vão de embute, dois Instructables impecáveis...
Este, como fazerem uma Oficina num Móvelzinho articulado e cheio de truques, com rodas e tudo!



Complete workshop in a shelf
sachsie

Most Instructables projects require you to have some basic tools and a workshop available - unfortunately, most people do not have the space for these bare essentials available. Just like me.
My girlfriend and I live in a moderate sized apartment for some years now. We have got a spare room that offers sufficient room for our hobbies. Now we expect a baby and this room is assigned to it. As a consequence, I have to move all my tools in a tiny compartment of an IKEA shelf and have to find a new workspace too.
I approached this problem, by building a compact yet solid frame made of low-cost aluminum extrusions. It offers some very handy features:
  • storage space and organization for my tools
  • frame acts as a multi-purpose workbench. It offers:
    • a drill press
    • a router table
    • a bench vise
  • Concept is very flexible and may find further extensions.
Everything is designed to fit the size of the compartment. Total costs of this project are about 150 EUR.











Faz frio que se farta, pelo menos em Portugal, mas eis como terem, e até fazerem, a vossa comida quentinha para onde quer que
forem, com quase lenha nenhuma!
E facílimo de se fazer:




UPDATE! Backpacking Gasifier Stove
Quark-

Hello, this is Quark- and I am here to show you how to make your own TLUD (Top Level Updraft gasifier stove), and you can look them up at http://www.build-a-gasifier.com/gasifier-wood-stov.... They are essentially a stove that burns the fuel not once, but twice. The base thermos holes allow air into the fuel, while the top holes allow preheated air down into the stove to basically burn the fires smoke. I recently learned about the design while looking up specification for the popular Biolite Campstove, a design which I sought to make. Only then did I learn that it was a gasifier, and the rest is history. They are often used in third world countries, due to the fact that they are incredibly cheap to manufacture and are 10x more efficient than just a plain fire. Because of the double-walled construction, it is easy to use a simple food thermos to make one of these beauties. Enough talking, Onward!





Publicidade, eis um jogo bacana:



 
Game of War - Fire Age - iOS
Join the ULTIMATE battle for domination of the Kingdom in Game of War – Fire Age! PLAY FOR FREE in the most addicting, interactive Action Strategy MMO GAME!




quinta-feira, 12 de fevereiro de 2015

Reparar rodas dentadas? E 2 pró Raspi, um Forno Português, e um Centralizador

Este Instructable, pela sua simplicidade e eficiência, é uma Obra-Prima de Reparação Engenhocas... 
Olhem que usar os dentes das outras Rodas dentadas, como Molde para a roda dentada partida, é de puro Génio!




Broken Gear Repair
Fab Muchada

Simple way to fix broken gear
you need a plastic steel epoxy, Popsicle stick, any mixing medium for your epoxy mixture and brush and detergent soap or dish washing liquid.



www.instructables.com/id/Broken-Gear-Repair/











Duas dicas de Fernando Mattoso Lemos, 2 Adaptadores que unem o Arduino ao Raspberry Pi;
O primeiro, é o Raspio, um projecto que já ultrapassou quase 3 vezes o seu Objectivo de 3.456 Libras, e pode funcionar autónomamente, uma vez programado, ou comiunicar com o Raspi, como periférico:





RasPiO Duino Affordable Arduino Programming On Raspberry Pi

Alex Eames 

I want to get you into the wonderful world of Arduino programming, using your Raspberry Pi as the programmer. There's so much you can do with the ATMEGA 328 microcontroller - it complements the Pi perfectly and for many applications it doesn't even need to be connected to the Pi, once it's programmed. So I've designed the RasPiO Duino, which...
  • Has a capable microcontroller: ATMEGA328P. 32KB flash. 20MHz
  • 6 analog inputs for reading sensors (light, temperature,  pressure etc.)
  • 14 digital input/output pins for controlling and switching things
  • 6 PWM outputs for variable LED brightness or motor speed control
  • Can control up to 12 servos
  • Can exchange the microcontroller as it is socketed
  • Fits on the GPIO header and is programmed directly from a Raspberry Pi
  • Uses the Arduino Integrated Development Environment for programming
  • Is very keenly priced

O segundo, é o Arduberry, que já está à venda, com uma Empresa fundada para isso, e tudo:




Arduberry: Raspberry Pi and Arduino for the Rest of Us

Students, hackers, tinkerers unite!  The Arduberry is the shield you’ve been waiting for.  The Arduberry connects the Raspberry Pi and Arduino.
We love Arduino and we love Raspberry Pi.  We thought they should be together.  The Arduberry marries the Raspberry Pi and the Arduino.  Simple, elegant: all you need and nothing you don’t.












Um Instructable dum Forno Português, da autoria dum Entusuiasta Estrangeiro!
Ora toma!
Eis como podem fazer um Forno que serve para vários fins, bem à moda do Desenrasca Lusitano, que nos tem aguentado a todos nós, como Nação e Diàspora, contra ventos e marés, pela bonita idade de 800 anos...



How to Build a Portuguese Wood Fired Brick Pizza Oven
grillsnovensllc 

Welcome!
In this instructable we will describe how to build a real Portuguese brick pizza oven.
Portuguese ovens are characterized by higher dome than the Italian / Neapolitan ovens. What this means in practice is less intense heat. In all of these ovens the heat is reflected from the dome back onto the cooking floor and the lower the dome the higher the heat. While the Italian pizza ovens are made primarily for pizza (they cook other foods too, but most people buy them for pizza) the Portuguese ovens are made with cooking a variety of foods in mind: slow roasts, lasagnas, bread etc. For all of these you will need less heat than for pizza and hence a Portguese ovens can come in handy.








Este Instructable, vem com o seu Ficheiro 3D, por isso, podem finalmente usar as vossas Impressoras 3D num Instructable que faz sempre falta, uma gigajoga que acha os Centros em peças duma forma simples:





Center finder
mobilow

I love tools and every now and then I also love tools to make live easier. This one is based on a one time tool from woodpeckers but not available anymore. So I decided to made one by myself using my 3D FDM printer.
Its a handy tool to mark the centre of a workpiece, just place the two legs around your piece and mark a line or point or draw a line with a pen trough one of the holes in the middle bar. Due to the parallelogram, the center is always found automatically.