DIY High Voltage 8V-120V 0-15A CC/CV Small Portable Adjustable Bench Power Supply

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Introduction: DIY High Voltage 8V-120V 0-15A CC/CV Small Portable Adjustable Bench Power Supply

About: I mainly take on projects I have seen here and put my own twist on them. I also like to take garbage or thrown out electronics and make something nice from them. I have no certain area of Expertise, I am new...

Great little 100V 15Amp Power Supply that can be used just about anywhere. High Voltage, medium Amps. Can be used to charge that E-Bike, or just a basic 18650. Can also be used on just about any DIY project, when testing. The Pro Tip for this build is how to create a very Powerful but small Charger/Bench PowerSupply! Makes a Great Bench Power Supply. I added the Extra Voltmeter to the Converter Module, so when I am charging, I have voltage on the Voltmeter and Amps on the Module. The other voltmeter in the lower left corner is the Power going into the fan from the Boost Converter. This is also a Portable device(9x6x4.5inches) if you need it on the go. Just make sure to carry a DC jack to whatever Jack, your using with your Battery Pack. I have an Extra DC to XT60 connector I use. You can plug that into the side next to the Fan adjustment hole. SDPT switch on the top, keeps the 24V 9amp Power supply Isolated from the Battery pack with just a simple switch. Uses a Buck Converter to control the speed of the fan if it gets too loud. Here are the steps I used when I built this. Even though this instructable is long, the build is pretty simple. I am sure you could make this with the same parts a little easier. Please message me here and show me your build if you decided to build one yourself. Here is the steps.

Please, Don't forget to Vote! I would love to win a 3D Printer(currently out of my Price Range). There is so many things I could do with one. I would definitely incorporate this in my DIYs! Thanks for showing Support!

Pro Tips Challenge

This is an entry in the
Pro Tips Challenge

Step 1: Lay Out and Look Over All Your Part and Pieces Need for the Build.

I try and make it a point to layout all my parts and pieces need for the build. Look over the components and make sure there are no defect. I also Tested the DC to DC Boost Converter(BST-900) and 24V power supply. I had the 900Watt Boost Converter from a previous build where I ended up using a 1200 watt instead. The 24V 6Amp(9amp) power supply was also left over from a soldering Iron station build, where I ended up with 2 of them. Then just recently I had a project where I needed a 1p10S battery Pack and a 42V charger. The Imax B6 I am using is not capable of doing 10s 42V battery packs. Remembered that the Boost Converter could do up to 120V, I decided that this would make a Great Project.Looking through my stock and some leftover Pletsiglass. I ended up only needing to purchase the wood from the local hardware store. Please message me if you need a link to any of the parts, most of them were purchased a while back(reason for the missing links). Here is the list-

MingHe 900Watt DC to DC Boost Converter 8-60V to 10-120V 15Amp Max
AC DC Inverter 110V 220V 100V-265V to 24V 6Amp (9amp max) Switching Power Supply SMPS Adapter

LM2596 DC-DC Buck adjustable Step-down Power Supply Module

Mini DC 0-100V 3-Wire Voltmeter Blue LED

Mini DC 3.3-30V 2 wire Voltmeter Blue LED

16 AWG Black and Red Silicone Wire

10 AWG Black and Red Silicone Wire

12 AWG Black and Red Silicone Wire

10 AWG White Silicone Wire

5.5MMX 2.1 2 Pin Female Power Jack

Haitronic 20cm Jumper Wires/Dupont Cable

VOSO Amplifier Speaker Terminal Binding Post Banana Plug

Kester Solder 24-6040-0027 60/40 Stand 0.031

Kester 951 & 186 Liquid Flux

Mis. Shrink Tubing Sleeves

ON/OFF/ON 3 Positions SPDT Round Boat Rocker Switch 10A/125V 6A/250V

The 3 prong Mains AC Female, The AC with Light Power switch & 12V Fan was salvaged from a broken Computer Power Supply.

4 x Red Cap SPST Momentary Mini Push Button Switch (Normally Open)

4 x 1/4in Maple Board from the local Hardware Store

8 x 1/4in Maple Board from the local Hardware Store

Clear Coat Spray from the local Hardware Store

Lexan Polycarbonate Sheet .093 Clear (Plaskolite)"Can use Plastiglass"

M5 Bolts and Nuts set Mis from the local Hardware Store

Mis screws salvaged from other projects.

Gorilla Superglue, Wood Putty and Wood Glue from the local Hardware Store

Step 2: Write Out the Size of the Box and the Draw Up the Schematics

I will lay out the bigger parts on a piece of graph paper, to get a rough Idea, on the size I will need for the box or case. With this one, I ended up figuring I would need a box 9inch x 6inch x 4 1/2inch. I will then write out my schematics, so I also know how to wire, when the time comes. I will also write notes to self, just to make sure I am reminded when I decided to build. Making a schematic will ensure no question to self, when you decide to wire everything up. I also like to lay out the face design This is normally changed at the end, but it still gives me something to go off of when I decide to drill my holes. Great thing about the graph Paper, I can use exact measurement when I write everything out.

Step 3: Cut the Wood and Plexiglass Needed for the Project and Dry Fit the Parts.

Luckily the Maple board I had purchased was close to the size needed. All I really had to do was cut the length of each board.I just used a basic box design, using the size I came up with in step 2. The Plexiglass is 1/4 inch thick and very simple to cut. I used a plexiglass cutting tool. Both the face and back was the exact same cut, at 9 x 6 inches. The top board, I made sure to cut to 9" and the side, I took 1/2" off the 6inch to make up for the thickness of the top and bottom boards. The cut was 5 1/2 inches. I am sure if you had the tools, you could cut to length and use a 45-degree when cutting the end. I will then place the bigger parts in the frame, held up with whatever I have around. This will give me a rough idea of where I need to place everything and if it's efficient. I ended up deciding to switch the position of the Boost Converter and power supply. I also decided the fan would be more efficient facing the Boost Converter.

Quick Note: On most of my builds that require a fan for cooling. I always use the Buck or a Buck/Boost converter for adjusting the fan speed. Instead of desoldering the small potentiometer. I will just drill a small hole over the converter, in the case and face the converter to the outside of the case. It's not that often you have to adjust the fan speed. But it is nice to have.

Step 4: Draw Out Where the Components on the Case Got and Drill or Dremel Out.

I started with the fan because this would have the most holes drilled. I also lined up the Buck converter so I could mount and drill the hole showing the potentiometer screw. I also decided, to add two more M5 screws, connecting to the power out, to the fan(positive and negative). I like to do this, so I can measure with a multimeter the voltage going into the fan. With the fan, I drew out where it would sit and the circular part where the fan spins. Later I drew out a 1/4" x 1/4" grid or squares, where I would drill 1/8" holes for air flow. I kept the grid inside the circular area. This just makes the holes look a little more symmetrical. I measured where the buck converter and power supply would sit and added the holes for the Mains Power switch and plug. So the fan's air has an outlet and flows over the Main parts, I decided to drill some 3/16" holes on the opposite side, below the mains plug and switch. I measured where I would place the ON/OFF/ON 3 Positions SPDT Round Switch at the top. I like to start with a 1/16" drill bit and work my way to 1/8" Then I will finish off with a step bit. I will add tape to the step bit so I don't make the hole too large. The square Mains and the oddly shaped power-in for the mains, I finished up with a file. I also make it a point to draw out the hole size, so I don't make them to big. Finally, dry fitted the main components(converter and PSU) and drill the mounting holes in the back of the case. Looks like computer motherboard screws will work great for this.

Step 5: Dry Fit , Glue the Case Together and Clear Coat

I will take all the components and dry fit them again to make sure everything lines up and nothing gets in the way. I do this before I glue up the box. Using Small screws, I will predrill and countersink before gluing together. I like to use Gorilla wood glue for projects like this. I will use rubberband on the side and something very heavy to hold the back in place when drying. The Glue says to wait 24 hours for it to fully cure. I used my toolbox filled with New 18650s as weight. I also decided to use some hot glue on the inside of the box, just to help hold. When I feel the glue has set, I will take the small screws out of the sides. Once the glue sets, I will use wood putty to fill the screw holes and sand when dry. Typically wood putty dries pretty fast. Make sure to lightly sand the whole box frame before clear coating. I took the box outside, where there is plenty of ventilation and sprayed a few coats of clear. Make sure when you spray, to lightly coat and let it dry before adding another coat. This will prevent any runs with the clear coat. The clear coat gives the maple a nice wet look, that goes well with plexiglass. It also helps protect the frame from defects. It is good to allow the clear coat to dry completely overnight or at least 8 hours in warm weather.

I almost forgot. During the build. I knew how I wanted to mount the Boost converter's control board and 100V Voltmeter. I just wasn't sure how I was going to hold it in place to mount it where it looked floating.Rummaging around in some smaller clear cases I had saved, I found one that fit perfectly inside and was the perfect width. So I added some 1/4" x 1/4" maple pieces I had at the top and bottom of the case(inside), to use as a bracket. I had to glue and hold with some clamps I had.

Step 6: Dry Fit , Predrill and Screw the Boost Converters Control Board, and Plexiglass

After the wood glue dried and the clear coat set.It's time to start fitting parts. I took the clear lid and dremeled the top off straight to fit inside of the frame. I then placed the Control board and the Voltmeter in place and marked where they needed to be cut out. The back of the control board has 8 male pin headers on both sides. I took the 20cm Jumper Wires/Dupont Cable and made sure they would fit the hole I drilled and the Control board. I also tried to use the same colors on both sides. Once I had the holes drilled, I used plastic nuts and bolts on the voltmeter and Hot glue on the control board to hold them in place. I placed the plexiglass face on the frame, to make sure everything is flush. With the face on, I decided to predrill and add screws. I made sure to draw out the frame on the face because it has a protective film. This will help me when I predrill. I also measured the holes on all 4 sides to keep them straight. Figured 2 inches from the side on the top and bottom, 1 1/2 inches for the side. when predrilling the holes for the face, I used the 1/16 inch bit to drill both the face and wood. Then I used a 1/8" on the face only before screwing in the screws. With the control board holder, I used glasses frame screws to hold this in place.

Step 7: Lined Up, Predrilled and Hacked a Few Momentary Button to Use With the Control-board. Drill Banana Plug Holes.

While I had the screws in the face, Figured I could draw the holes for predrilling. I wasn't sure if I would just use a pin's inside for the buttons. Then I looked at a small momentary button I had. I decided to take the button apart to see what it was made of. Then it hit me. I could just cut off the bottom part of the button. This would leave me with the small metal contact and the top part of the button and panel mount section.Taking the small metal piece off and removing the spring. I screwed the button in place.It would hit the button on the Control board perfect. Nothing falling out and it looked like it belonged. But with 4 together it would be to wide. So I had to take the red button out and use this only(I could have just used the red plastic from the start). I then decided, to add the small metal piece, so it had more surface area to hit the button on the control panel. Found out this would also help hold the red part of the button in.I just took some Gorilla Super glue and attached the metal to the button. After it dried, it worked well and made contact each time with the momentaries on the control board. My only regret was leaving the spring off of the button. This would have helped keep the button a little straight when sitting upright, but not needed. Glad I figured this out, I can see these button coming into play with some upcoming project I have.While I had the face, I figured I would drill the last holes in the face for the Banana plugs. Just made sure to measure both sides before drawing the dot to drill. The banana plug and the small momentary button used a panel mount cutout hole at 1/8". When I drill in plastic like material. I like to use the point on a tack to use as a punch. You can use anything with a fine point. I also screwed in all parts that belong on the face.

Step 8: Tin or Soldered All Wiring and Installed the Parts Belonging to the Outside Frame.

If all the previous prepping was done correctly. You should be able to guestimate the wiring needed. Solder and tin wiring needed for the mains, the fan and buck converter and the on/off/on switch. Using the schematics, connect the mains to the mains switch and get it ready for the 24v PSU. Install the fan and solder to the output of the buck converter. On the output of the small buck converter, connect to the 2 screws. From the incoming side, add 2 longer wires that will connect to the on/off/on switch common(this ensures power on mains or DC. Install the DC jack and add 2 wires. Dc Jack is on the fan side. Make sure all extra wiring is long enough to reach the switch or the Boost converter. Leave only the On/Off/On switch wireless. We'll add all the wiring to the switch when everything is in the case.I used Hot glue to help hold the wiring and the parts in place.

Step 9: Prep and Install the Power Supply, Add Incoming Voltmeter.

With the frame prepped and all the wiring ready. Add the wiring on the DC side to the Power Supply. It might be hard to get to it, once it is screwed in.Install the power supply and screw in the mounting screws in the back of the unit. The Mains coming from the switch(live) and the Plugin(neutral and ground).will screw directly to the power supply. The Ground will need to be screwed to the mounting hole next to the terminal. Make sure you connect this on the mains side. Now the PSU can be powered. From the positive DC terminal(PSU)solder it to the right side of the On/Off/On switch. Solder the Positive from the DC jack on the left side of the On/Off/On switch. Solder another extra Red Wire along with the positive coming from the fan's buck converter(incoming) to the common, on the switch and leave it hanging for the boost converter. Take the negative from the buck converters negative side, the negative from the power supply and the negative from the DC jack and solder together or use a terminal block Make sure to add another negative wire for the Buck converter. I used a terminal block, I also like to use a multimeter and check continuity of all wiring. I will also use Hot glue to isolate the On/off/on plug instead of wrap. With everything complete and waiting for the Boost Converter, install the incoming Voltmeter. Because this will use the incoming voltage, just like the Fan's Buck Converter input power. You can splice into the wiring, solder, and tape. Now the incoming power to the buck converter (top)and the voltmeter will connect to the positive common (ON/off/On switch)and negative shared.

Step 10: Prep and Install 900Watt Boost Convert(BST-900).

Taking the banana plugs brass wire connector. Solder a red and black wire to each, make sure the wire is long enough to reach the boost converter with the face open(helps later on). connect these wires to the Boost converter on the output side according to the polarity on the device. Add the Boost convert to the unit and screw in the back with the mounting holes.There should be one red wire coming from the common on/off/on switch and one black wire coming from the dc jack, Power supply, fan's buck converter and Voltmeter.(you could also use the Extra negative terminal coming out from the power supply). Connect them to the input of the boost converter. You should now only have the 2 wires that screw into the banana plugs hangout of the case. I may have decided to add the positive wire a little later when I installed the face. It can be done either way.

Step 11: Finish Up by Installing the 2 X 8 Pin Header, Voltmeter and Banana Jacks.

Add the 8 pin 20cm Jumper Wires/Dupont Cable to each side of the control module. Use hot glue to keep them together and connected to the back. With the male side of the 8 pin headers, connect to the Boost Converter. Make sure you keep the wiring in order and on the correct side. Bend the jumper cable to the side and install the floating lid holder. Screw in place. Take the red and Blue wire from the 100V Voltmeter and splice or solder to the wires going to the banana plugs. Make sure blue is positive and black is negative. With the 3rd red wire, connect to the red wire of the first voltmeter. This will supply power under 30v's at all times. Finally, connect the banana jack to the connector and bolt in. Should have some extra wire, so it easy to work on and install. It's technically the only part connected to the face.Screw the face on! Now its time to Test!

Step 12: Operations and Testing

Plug in the mains and switch the device on. Make sure the On/Off/On switch is switch to the mains side. You will see the light from the power supply come on and then something will show on the Control Module. Adjust and test voltage. You should also see the 24V on the corner left side voltmeter that shows input voltage. I found this link with instruction on how to use the Boost converter-

http://files.banggood.com/2016/07/User's-manual-of... The reason I added the 100V Voltmeter-When charging, I like to see the Voltage and the amps. With the addition of the Voltmeter, I can use the Module to keep track of the amps. Without the voltmeter, you can only have one or the other with the module. I have seen this converter used to charge e-bikes, run a 120volt light and charge 18650. If I need smaller voltage or I decide to go portable. I can take any battery pack, with the battery pack connected to DC adapter(8volt or higher). Plug into the side(fan side) and switch the ON/Off/On to the Opposite side. This will supply voltage to the Boost convert directly, still running the fan and the voltmeters. You can even use a smaller DC jack to charge batteries under 24V. With the built-in CC/CV with LED. This DC converter is perfect for the higher voltage packs. This is my First Instructable, and hopefully not my last. I will try and post them as I post my Youtube videos. New at that also. It is also very late where I am, and if you see any mistakes, please let me know so I can correct them. I also know, what a pain it can be to research parts when you are new to DIYing. Some of the terminology and Opinions on how to build can be so confusing. Please feel free to ask me anything. I will give you the njfulwider5 Version and it may help.

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    Tips

    1 Questions

    Sorry for the late response, for some reason I just got the email with your question. Great Question!!This is just a guestimate. Most of this, I had left over from a previous build and finally found a use for the higher voltage. Here is what I am guestimating-

    MingHe 900Watt DC to DC Boost Converter 8-60V to 10-120V 15Amp Max--->$18

    AC DC Inverter 110V 220V 100V-265V to 24V 6Amp (9amp max) Switching Power Supply SMPS Adapter-->12$(make sure to buy the same one in the post, so many version out there.)

    LM2596 DC-DC Buck adjustable Step-down Power Supply Module-->1$, (purchased a bulk order for 10 at 10$)

    Mini DC 0-100V 3-Wire Voltmeter Blue LED-->$1.50

    Mini DC 3.3-30V 2 wire Voltmeter Blue LED-->$1.50

    16 AWG Black and Red Silicone Wire-->$1 worth(purchased at another time-5 feet for $10)

    10 AWG Black and Red Silicone Wire-->1$ worth(purchased at another time-5 feet for 14$)

    12 AWG Black and Red Silicone Wire-->1$ worth(purchased at another time-5 feet for 12$)

    10 AWG White Silicone Wire-->1$ worth(purchased at another time- 5 feet for 14$)

    5.5MMX 2.1 2 Pin Female Power Jack-->.50 cents(purchased at another time-20 for 10$)

    Haitronic 20cm Jumper Wires/Dupont Cable-->50 cents(purchased 120 at another time for 8.50$)

    VOSO Amplifier Speaker Terminal Binding Post Banana Plug-->$5

    Kester Solder 24-6040-0027 60/40 Stand 0.031(costed me 21.99 a few months back)

    Kester 951 & 186 Liquid Flux(costed me $9.99 a few months back)

    Mis. Shrink Tubing Sleeves(costed me around $6 a few months back)

    ON/OFF/ON 3 Positions SPDT Round Boat Rocker Switch 10A/125V 6A/250V-->.25 cents(purchased 50 a few months back)

    The 3 prong Mains AC Female, The AC with Light Power switch & 12V Fan was salvaged from a broken Computer Power Supply.(free from someone's throwaways)

    4 x Red Cap SPST Momentary Mini Push Button Switch (Normally Open)-.10 cents each(purchased a huge bag for $10 a few months back)

    4 x 1/4in Maple Board from the local Hardware Store-->$3

    8 x 1/4in Maple Board from the local Hardware Store-->$3

    Clear Coat Spray from the local Hardware Store-->$5

    1/4 in plexiglass from the local Hardware Store-->left overs, but each sheet was around $3

    M5 Bolts and Nuts set Mis from the local Hardware Store-->$10 for a huge lot of mis,

    Mis screws salvaged from other projects.(Free)

    Gorilla Superglue and Wood Glue from the local Hardware Store -->$5

    I am sure you could find the parts cheaper. Most of mine was purchased in the states for quicker delivery. I am starting to realize purchasing my Mis. parts and pieces from China is way way cheaper and well worth the wait. Total guestimated cost-->>$40 to $55 and that is being generous on ebay. Most of the items I had left over from previous builds.

    Thanks for the question!

    24 Comments

    A schematic would help. Not sure why you have two power supply modules

    3 replies

    There is only one Power supply that supplies a voltage of 24V 6-9amps. Then it is directed to a Boost Converter that boosts the supply voltage to the desired voltage. If you need voltage smaller then 24V, you can flip the 2p2t switch on the top of the unit and use the DC jack. With the DC jack, you can plug in any voltage as long as it is above 8 volts. If You have a battery pack and what to take the small supply on the go, you could also use the DC jack as long as you have the correct adapters. I have a Few XT60 to DC jacks I like to use.

    Schematics are in the video, and Step 2 has the Schematics also(see pictures).

    Thanks for commenting!

    Thanks that helps. I did try to look at the pictures in step 2, but couldn't make it out. I'll also look at the video. Nice project!

    Thanks!!Let me know if you have issues seeing it. If you can't make it out, I can take a clearer picture and post here.

    It's a really attractive PSU - and a bit of brute, too, in it's modest-yet-attractive casing!

    Personally I wouldn't use bare terminals like that at the front - though they are very pretty. I just have too many things on my bench that could accidentally short against one or both of them.

    I like your "floating" meters - though I'd have tried to make a panel for them the full size of the front of the unit so you wouldn't see any edges. But then I can see that could potentially look a bit naff in other ways.

    Why not make the fan speed be dependent on the temperature in the case? You can use a transistor to sense the temp in the case (or directly on the main heatsink you want to cool), use a 4 wire fan and connect a 556 dual timer as a voltage-controlled pwm fan speed controller.

    Another commentator raised concerns about EMI shielding. Simple solution to my mind is line the case with foil, then just the front is un-shielded. Also make is more fire-resistant...

    2 replies

    Here is one of the projects, I am currently working on an Instructable.Its a much bigger design, but only 32V 12amps, like the smaller one, it uses mains but can be powered by a battery pack. It uses the DPS3012, 1200W Boost Converter and a 24V15amp PSU. I also have a portable DPS 5005 Project, I completed I will post soon. I really like the DPS design and DC to DC Converters!

    IMG_1864.JPGIMG_1910.JPGIMG_1804.JPGIMG_2554.JPG

    Been playing around with some transistors and temp sensors. I just haven't the skill set to make the circuits, but I have been researching. I have built a few of the PWM controllers but found at my current level of experience. It far cheaper to just use a Buck converter with Potentiometer(1$). I have a circuit board I created with JLpcb, that works pretty good I might start using. I just built a Dremel where I played around with a few different designs, but ended up deciding against it. I learned to allot with that project.(I didn't post the experiments in the video, out of embarrassment)...LOL. I am sure as I keep building these, I will get to a point when I use PWMs and Temp sensing.

    I actually didn't even think about the shorting? I believe the Boost converter has some protection against shorting, but from what I hear it can still blow mofset if you don't watch the connections(Using a diode to prevent some of this). I have The other type(plastic looking red and black). I might just swap them out for saftey reason. Thanks for bringing that to my attention! I was to caught up in the look..LOL

    I don't seem to have any issue with the EMI like the other guy mentions, but if you look at his other comments, he seems to have commented the same way on other posts, other than mine. Guess this is something he worries about. The Power supply has some filtering(I believe) to help prevent this.If there is any EMI spilling, it is so small, it would never cause any issues anywhere. I use a cordless phone plugged in right next to this.(don't have a way to measure yet, but looking for something I can afford). Love your Idea on the shielding!

    I still feel pretty safe about the build. The Main 24V Power supply is earthed and fused.The Boost converter also comes with its own set of fuses.(the AC side is Earthed and Isolated from all DC connection) All connection are isolated with shrinkwrap and HotGlue, some area with both..LOL I also used New Silicone wire, instead of used. I really feel confident its a safe machine.

    Thank for the comment and the compliments! Thanks for the constructive Feedback. I will definitely look into changing out the Banana plugs. I have allot more I will be posting here, once I get a chance. Please take a peek and if you see any way I could better the design, or maybe you see something I am doing wrong. Please comment. I am fairly new and Still learning, with each build. I have learned mostly from watching Youtube Videos and Instructables. Hoping to pass along some of the stuff I have learned(from trial and error) to other. This Build is actually one of my simplest and easiest to build.

    Thanks again for the Constructive Feedback and suggestions!

    Me Tooo! I am fairly new to DIYing, and it seems that I've been doing a lot of projects like this. Maple with Plexiglass & Black Vinyl With Pletsiglass. Almost everything I build uses plexiglass. I should be posting those on Youtube and Instructables as I edit the videos. Thanks for commenting!

    Here is a few pics I found on some of the devices I built. You can find most of the units I built on my Google+ Profile. Will have Instructables on these soon also.

    IMG_2190.JPGIMG_0832.JPGIMG_2431.JPGIMG_1821.JPGIMG_1915.JPGIMG_2122.JPG

    FYI, what you used in the Instructable wasn't Plexiglass (PMMA, polymethylmethacrylate), but Lexan (PC, polycarbonate), which is much stronger.

    You are correct. I like to use this on anything I make, where you will be looking through to see the components.This is why I will use wood for the outside or Frame. Then I try to make sure there is a support other than the frame, so when I plug and unplug the banana plugs, it stays sturdy. On this unit, It is also using the plastic lid as a stabilizer of sorts. I like to use the thicker stuff when I am building a box and the plexiglass is the only stabilizer. I wasn't sure of the name, the reason I called it plexiglass. Was just some leftovers from an older project. Thank for the FYI!

    Don't get me wrong, this may not be the best way of doing this. But it seems to work on this particular project. I am sure you could use both if only one or the other is available.

    Thanks for commenting and the FYI, I will make sure to change the Parts list when I get to my Computer.

    For this kind of project, where the look of it is important, the ideal would actually be PMMA, because it's scratch resistant, unlike PC, which needs a special coating for preventing that from happening. But it's also very difficult to work with because it's very brittle. I mounted some premade PMMA parts and I accidentally exerted too much force with the screw and it cracked! That's why you must use a CNC router for cutting it. Plus, you can't bend it in cold, it breaks.

    Thanks again for the tips! On my next project, I may play around with the PMMA. I haven't ran into the issues you mentioned yet. But I have only been doing this for under a year. My First project used the Lexan and it has held up pretty well(hacked, bench PSU from a computer PSU). For me, it just seems to cut easy, bend when I heat it pretty well. When I cut it to size, I just use a Plexiglass cutter and sometimes a sharp knife. Then I snap it on a straight surface. I use a dremel on the small square cutouts. My only gripe-If you don't have a sharp drill bit, I have seen it crack all the across what I was working on, destroying all my work. Until I discovered step bits. Now I haven't really had this issue. I guess I just like the cheaper price compared to plexiglass(newbie and learning).

    Thanks again for the comment and the quick Tip! I will give the other stuff a try on my next project. It sounds like I will probably like it more than the stuff I am using now?

    I thought Lexan was the more expensive of the two?

    It might be? But the Home Depot where I purchased the sheets, at the time, Lexan was the cheaper of the 2. Maybe they had a sale when I first purchased these, I haven't had to buy more since my first purchase. Next Time I am at Home Depot, I will take a quick peek and see if the Lexan sheets are still cheaper then the rest. These are the 8" x 10" sheets from there I believe. The last batch lasted me forever..LOL

    This doesn't seem like a particularly good idea. Firstly using a switch mode supply without any metal shielding is going to spill EMI all over the place, especially at that kind of power. Secondly wood is flammable, so this is a bit of a safety hazard to say the least.

    4 replies

    Both Power supplies(24v and Boost converter) are pretty good at EMI, and Both have protection in place. I am not 100% sure how they are built, but I have never had any type of interference with any equipment I use. This actually sits 2-3 feet from our living room tv, Internet, Wireless telephones and Bluetooth Speaker system. Never had any issues. I am sure the people that designed both components accounted for this. If you feel this may be a problem, you can always add filters.

    When it comes to wood and flammability.If you take the time to make sure all connections are Isolated, and only use for its intention. You shouldn't have anything to worry about. When I use for charging, I am always present. You have to think, all homes are basically made from AC voltages and wires connected with only wire nuts. Where More electricity is flowing through them then this simple little charger. Soldering and Isolating the wiring safely, and I doubt you would ever have an issue. That don't mean you won't. Nobody can predict this. I just feel safer knowing I personally took my time to put together, than purchasing a plastic charger from a store. But again, I am no expert and this is just my personal opinion.

    But nothing is 100% safe, and with all electronics, you run the same risks.Electricity is no Joke and should never be taken lightly.

    Thanks for your comments!

    Do you actually have the necessary equipment and skills to justify what the EMI being produced is?

    I'm 100% sure these devices are designed to be enclosed in a grounded metal chassis if they are to meet emission regulations.

    EEVblog has some demonstrations of the failure modes for a number of these buck and boost regulators, most of them consist of large flames shooting out of board. If that can burn through FR02 PCB material then imagine what your wooden box will become, and then consequently your house.

    Nothing might be 100% safe, but I'm sorry to say that this is 100% dangerous.

    user

    Bro. You should chill out a bit. Just a suggestion. He's proud of what he's accomplished and I think. it's a fantastic instructable. Your entire. profile is about going around and commenting on Electro Magnetic interference on other benchtop psu's. That might have been a relevant term in like 1960. but there's no way EMI from a buck converter is going to start making nearby electronics shoot flames. or vice versa. you might get poor TV reception in the box that he built. other than that nobody cares dude. Why don't you do us all a favor, post your very first instructable about EMI and flame throwers, or whatever else you were trying to be rude about

    Thanks for your Opinion. Come on man?? I just built a DIY Power supply, that I feel is safe enough to use on my 42V Battery Pack. I was very proud of the way it came out and felt it work Great for my needs. I also was very proud of the way it looked.. Just sharing with all who are willing to view and who are interested. I would never, ever build something I don't feel is safe, and I can assure you I would never ever put my family in that type of danger. If you don't feel this is safe for you needs, then you can move on and find another project at your level. But I can assure you this is safe to build as long as you know what you are doing, have the skill level, and the common sense, with the basic know how. You can build a unit as safe as the one I just built.

    I really appreciate your opinion and I hope you find a project safe enough for your needs. I have many others I have built just like this I will be sharing soon. Please feel Free to comment with constructive feedback if you see something I can do better. I value all opinions and feedback as long as it remains constructive.

    Thanks again for your comment!