Microwave ovens have been ubiquitous in kitchens for the reason that Nineteen Eighties, however extra lately, intrepid tinkerers have been taking them aside to reap them for elements for their very own tasks. There’s a veritable gold mine of elements for DIY house inventors right here—from high-powered heavy-duty parts that can be utilized to make a Tesla coil to fundamental, sturdy elements for Arduino interest tasks.
Fortunately the overall setup of a microwave hasn’t modified all that a lot over time, making the identification and protected elimination of elements pretty simple. On this article, we’ll cowl taking aside the microwave safely and present some venture concepts varied inventors have provide you with utilizing the elements.
Earlier than You Get Began
There are three essential factors we have to go over earlier than you go forward with the whole course of:
- Microwaves are excessive voltage home equipment, and it’s best to by no means take them aside whereas plugged in. Moreover, the colour conventions for wiring can range from nation to nation. You’ll want to know what precisely you’re looking at.
- The excessive voltage capacitor may give you a deadly shock even after the microwave has been unplugged for months. We are going to present you how one can safely discharge these capacitors on this article, however they have to be revered.
- The magnetron inside a microwave can comprise beryllium oxide in its ceramic insulators, which may be deadly if it will get into the lungs. Merely eradicating it’s protected, however by no means attempt to take one aside. It is not price it!
Each time you knowingly tinker with excessive energy, it’s at your individual threat and probably lethal. Briefly, be protected! Reside to cover ugly know-how in your house one other day! Now, with that mentioned, let’s get began.
Step one is discovering your microwave. You’ll have an previous or changed unit—in our case, our neighbors had been eliminating theirs and left it in our stairwell. It’s price noting that this disassembly just isn’t appropriate for inverter microwaves as they work in another way.
You do not want many instruments for this disassembly, however this might range relying in your microwave’s design. We discovered the next instruments to be adequate:
- Phillips screwdriver with insulated deal with.
- Pliers with insulated handles.
- Heavy-duty insulated working gloves.
We discovered the gloves served a twin goal right here: Apart from defending us, they had been a pleasant barrier between our arms and the gathered years of filth contained in the microwave case. We additionally discovered it useful to have a small bowl subsequent to me to retailer all of the screws.
Earlier than getting began, test the case to see if it has any helpful info on it. Many microwaves have full circuit diagrams accessible to obtain on-line, which is an effective way to find out about circuit design, so make certain to notice down any mannequin numbers you discover. In case you are thinking about extra DIY electronics tasks, try this nice useful resource.
On this occasion, the producer kindly put a diagram of the interior electronics on the again of the case.
Simply in case you want a reminder this quickly, you needn’t perceive German to know that one thing with “Achtung” and “Warnung” on it may probably be harmful!
Screw Right here, Screw There
Examine that the microwave is unplugged.
Examine once more. We will wait.
Now start by eradicating all of the screws you may see on the outer casing. You could discover that the highest a part of the casing may be eliminated first with the screws across the edges, supplying you with sufficient entry to reap the elements with out completely taking it aside, although some fashions are tougher to interrupt into than others.
After you have the outer casing off, it’s best to have the ability to see the parts. Whereas the format could range, nearly all microwaves have the identical set of basic elements.
- Transformer (generally known as MOT).
- Excessive Voltage Capacitor.
- Compact Excessive Capability Thermostat (small black round element).
- Entrance Panel.
The very very first thing to find is the capacitor. On this mannequin, it was a part of the fan meeting, although this could range. Don’t contact the contacts of the capacitor beneath any circumstances! In case the above picture just isn’t clear, that is what you might be searching for:
If attainable, it’s best to discharge the capacitor earlier than elimination. On this occasion, the capacitor was encased within the fan meeting, so it required elimination earlier than discharging.
Whereas carrying your gloves and holding the insulated deal with, use your screwdriver or pliers to quick each contacts of the capacitor. Maintain it there for a number of moments, ensuring it’s undoubtedly touching each contacts. You might even see a flash or hear a loud pop, so do not say we did not warn you!
Magnetron, Transfer Over!
Magnetrons may be extremely harmful; while you’re protected from radiation when they don’t seem to be powered, the ceramic insulators can comprise beryllium oxide, which may be deadly when inhaled. If Magneto is the enemy of the X-Males, the magnetron is the enemy of all lungs in all places.
We are going to rigorously take away it from the case, however solely to achieve entry to the screws holding the transformer. In the event you can take away the transformer with out eradicating the magnetron, depart it the place it’s.
Most magnetrons seem like this and are connected to the principle microwave case with 4 screws. Rigorously take away it, wrap it up, and put it apart to be safely discarded later.
The excessive voltage transformer (generally generally known as a Microwave Oven Transformer, or MOT) is the true prize on this disassembly. The MOT takes mains AC energy (240v right here, it might be totally different for you) into the first coil and thru electromagnetic induction steps that energy up in order that between 1,800 and a pair of,800 volts come out of the secondary coil. The extra windings you might have on the secondary, the upper the voltage and decrease the amps and vice versa.
Excessive voltage transformers may be costly objects to purchase for interest or DIY use, however with cautious modification, MOTs can be utilized to supply a excessive vary of various energy necessities.
The MOT is heavy, so it’s nearly at all times connected to the underside of the casing by two or 4 screws. Rigorously take away the wires and screws and pull out your prize.
There are a number of implausible tasks you are able to do with this beast, which we’ll go over later on this article.
Stripping the Relaxation
Now that you’ve got the larger parts out, slowly take away the whole lot else piece by piece. You could discover it simpler than we did for those who take away all of the wiring first.
Do not forget to take the underside panel out to take away the turntable motor!
After you have the whole lot out, it’s best to have fairly a set of parts:
Relying on how trendy your microwave is, your haul could range a bit. On this occasion, we got here out with:
- 1 x Highly effective 240v AC pole motor from the fan.
- 1 x 240v geared motor from the turntable.
- 1 x Small 240v Bulb with becoming.
- 5 x Micro switches.
- 3 x Excessive voltage thermostat switches.
- 1 x 20w 20 ohm resistor.
- 1 x Electrical heating factor (this explicit microwave had a grill perform).
- 1 x 12v relay.
- 1 x 240AC to 12v transformer.
- 1 x Excessive voltage transformer.
- Numerous items of excessive voltage rated wire and the mains lead.
Together with these items, we additionally bought assorted smaller resistors, diodes, capacitors, and an inductor.
We additionally stripped the entrance panel of the microwave off as one piece. This comprises a motor for the timer together with two extra micro switches. This unit is already self-contained and compact and may be put to a different use, as you will note later.
Now that you’ve got the whole lot you want, collect the items you’ll not be protecting for disposal. A sensible manner to do that is to reassemble the outer case with the magnetron inside it after which take the entire unit to your native recycling middle for protected disposal. Completely different locations have totally different guidelines for equipment disposal, make sure you comply together with your native guidelines and rules.
Now we’ve got all of those elements, what lets do with them? A few of them are fairly specialised and can solely be wanted in fairly particular conditions. A few of them, nevertheless, may be put to make use of right here and now.
The micro switches we scavenged are momentary, usually open (NO), usually closed (NC), or selector switches that are rated as much as 16A 250v (bear in mind, yours could range relying in your nation).
Whereas able to excessive voltages, they will even do completely high quality for smaller-scale tasks. As a result of they’re spring-loaded, they may simply be fitted to door and window frames as an alternative of reed switches as a part of a DIY house safety system. In case you are new to working with microcontrollers, additionally they work completely in Arduino newbie tasks.
As an added bonus, we discovered that the wiring that was additionally salvaged suits completely into the holes on a breadboard.
We’ve got coated utilizing 5V relays with microcontrollers earlier than, and you may apply the identical ideas to the relay we salvaged.
The relay we stripped from the microwave specifies a 12V coil, although many relays function at a decrease voltage. The relay we stripped, on this case, works completely nicely with solely 9V, making it the proper relay to make use of in a microcontroller venture, and for the reason that relay right here is able to taking as much as 250V 16A would have the ability to maintain use in nearly any house automation setting.
You will discover knowledge sheets for many parts by looking out the model and mannequin quantity.
A contributor for Instructables has supplied a easy information to connecting a 12V relay to an Arduino.
The motor connected to the fan is a pole motor, which runs at 240V AC. It has the benefit of being very highly effective whereas remaining pretty quiet.
This makes it good to be used as a do-it-yourself fume extractor fan, which is one thing everybody who owns a soldering iron ought to have.
By modifying this design by John Ward to utilize the fan, you may create a strong extractor on a low funds.
John estimated that this construct value roughly $90, although, with out the fan’s added value and intelligent reuse of different scavenged elements, that is the proper funds (and health-conscious) DIY venture.
The Entrance Panel
The entrance panel of the microwave above was one of many older fashions with a motor that counts down earlier than turning the micro swap off, although yours could have a more moderen digital show. This unit might be used as it’s as a countdown timer—good for reminding you to rise up and stretch after a interval in entrance of the pc!
The inner micro swap may also be used to manage an equipment. Person Koil_1 used a digital timer to create a multi-appliance shut-off timer on Instructables.
Crank up the Energy
The turntable motor in a microwave is geared to maneuver very slowly from an AC energy supply. Which means that the excessive torque motor is able to producing energy when turned manually. In a splendidly easy venture on Instructables, person ahmedebeed555 has created a hand-cranked telephone charger utilizing subsequent to no elements!
Earlier within the article, we talked about that the microwave oven transformer (MOT) was probably the most worthwhile half to scavenge from a microwave, and a fast Google search will reveal why. These transformers have been re-purposed to create many bizarre, wacky, and generally downright harmful innovations—the whole lot from do-it-yourself electrical arcs and metallic melting foundries to identify and welding machines.
YouTube channel TKOR has a collection of movies overlaying most of those tasks, and whereas they’re all nice concepts, his movies on making a do-it-yourself ARC welder give clear directions on how one can make your individual welding arrange on a small funds.
All in a Day’s Scavenging
This text has coated just some issues you can also make from an previous or damaged microwave, and even the smaller elements that don’t have any instant use are extra issues in your toolkit for future tasks. Scavenging and re-purposing previous home equipment is an effective way to find out about electronics and cuts again on the quantity of waste we produce.
Earlier than you go, bear in mind at all times to make use of warning when working with high-powered electronics. Additionally, remember to put on protecting gear the place applicable to make sure your security. Electrical accidents are extra frequent than you assume.