David Malawey

KEEPING ORGANIZED: Here’s how materials continually arrive at the lab without making clutter.

We discard as much as possible, such as labels and packaging. And do it right away.

We indicate on the parts some simple identification & date. And separately, we put together a PDF that contains all the data that shipped with the parts.

The PDF gets a simple name with the date, and the text inside gains OCR (optical character recognition. Later, these PDFs are searchable by the text inside. So the filename is less important.

When the material gets used, I may need some further data about its origins and specs. That’s when I go back to the PC (or google drive on mobile) and search my keyword. That returns all the data I need.

If the material becomes part of a design, the design has full details and material specs are attached, just like a scientific work. If the material proves highly useful, it gains a level of standardization and we add documentation and rigor to the sourcing effort.

PS: Did you ever work with Kevlar before? What did you make?

Skip the Carousel

1 2 3 4 5 6 7

1 week ago | [YT] | 134

David Malawey

HOW STRONG are these TUBES when used as BEAMS? 🏗️

Three materials are ubiquitous in DIY projects and entirely valid beam materials.
👉 Steel EMT Conduit
👉 Iron Pipe
👉 Steel Fence Rails

🏋️Our designs of load-bearing equipment (tables, work-surfaces, robot gantry, etc can integrate the best choice if we know the material behavior. In my last post I shared metrics for Aluminum extrusions and wood: rectangular stock. This post covers round tubes & pipes.

You know these materials: the 3/4 structural pipe is used in pipe clamps for woodwork. The EMT 1/2 and 3/4 joins to common steel electrical boxes.

📊 Use the charts to see how long of a beam can carry a 10kg point load without deflecting (deflection less than 2mm). See the cost to decide what’s most sensible when you’re using the tube as a beam.

🤔For each material, you’ve seen me integrate them already. The 1/2 inch EMT appears with the Handybox parts in hanging rack designs . The 1 inch EMT has a printable joint already. The fence rail was featured in my closet design video.

🌍AS for Europe: Surely these are less common specs but you must also have steel tubes available. What are the most economical and available steel tubes in Europe?

Skip the Carousel

1 2 3 4 5 6 7 8 9

1 week ago | [YT] | 170

David Malawey

To build structures we need to know the material’s strength. HOW STRONG ARE THESE BEAMS? It may surprise you.

➡️ aluminum 2020
➡️ aluminum 3030
➡️ steel strut channel
➡️ pine lumber

These are the key beams for OpenLab, selected to form frames from shelving to robots. But an Engineer can’t tell you the strength in plain English, we can only tell you
🤓Modulus of Elasticity (E),
🤓Area Moment of Inertia (I), and
📝 ask you to specify the bending axis and
📝 the supporting criteria. You’re lost. What can we do?

The Engineers in Open Source ecosystems must help a bit more. We can rebuild your question so it’s answerable. In this evaluation I specified the bending axis and defined strength in a simple way: With simple support and 10kg load, the beam doesn’t bend. I defined “does not bend” as 2mm deflection, the threshold where a person could likely detect the bending by feel.

Now we can compare. You’ll see the chart answering this: Report the strength in terms of a length. How long can the material span before bending? The photos express the meaning of a simple support, and single point loading.

Three materials and 6 answers, based on 6 setups. 👉 small 20mm extrusion can span 80 cm.
👉 big 30mm extrusion can span 120cm.
👉 steel is stronger yet, and
👉 pine is strongest.

❓Does this help you understand the materials’ strengths?❓

Skip the Carousel

1 2 3 4 5 6 7 8

2 weeks ago | [YT] | 275

David Malawey

🥵The heat rose to an untenable level. I had to halt everything and take an action. This home is not suitable for our new climate.

🍋‍🟩LimeWash is reported to produce NET COOLING in the best case and 90% heat rejection in a typical case. There simply aren’t enough trees by my home to give a partial shade that most of the local homes have.

🪣My formula is listed in photos. Hydrated Lime is the main ingredient. Wet the roof before you begin, so you can mix the coating thick and it spreads more evenly. Adding a THICK nap roller made the coats go down 2x faster.

🕐It’s noon in Bryan Texas and I think the HVAC is already responding with a lower workload.

20% of the roof is coated. tomorrow to continue. No, it won’t wash off in the rain. Chem reaction cures the lime with airborne CO2. Has anyone taken extreme measures like I’m doing?

Skip the Carousel

1 2 3 4 5 6 7 8 9 10

3 weeks ago | [YT] | 301

David Malawey

How does it look when a mechanical engineer is researching? These images are snipped from my research spreadsheets for HYDRAULICS.
👇
Research = asking questions & finding answers.
👆
(I took snippets of my excel spreadsheet but it’s not intended that you understand all the details.)

🙂 The interesting questions I’m answering:

✅ What type of hydraulics systems produce pressures between 100 to 10,000 psi?

✅ What systems are more accessible than industrial hydraulics?

✅ what type of fittings and lines can support a system having 2,000 psi?

✅ what pressures are delivered by the pumps of these systems? (power steering, brake systems)

✅ What force can I produce with a power steering pump, connected to a small cylinder?

✅ what pressures live in the familiar brake lines in my car?

Skip the Carousel

1 2 3 4 5 6 7 8

3 weeks ago | [YT] | 108

David Malawey

[My blue/white icon means Free & Open content]

Dear friends, 🙏as most of you know, I'm an engineer more than I'm a youtuber. So, I post designs on GrabCAD and Makerworld, I build repositories on Github, and I've formed web pages from the github repos. It all connects to the youtube content. ▶️

I posted a new icon for my youtube page, and I use the same icon on my other profiles. This is just to make it easier to recognize where I am authoring content for you. Whenever you see this icon there should be:
1) free and open access
2) engineering grade designs & literature
3) connection to my other posts.

For example, I'm using Youtube to explain a design for a printable hinge, and I use grabCAD to post the raw CAD files for download. Then I use Github to write up documentation such as the required tools and supplies to build systems with the joint and other printable parts.

Skip the Carousel

1 2 3 4

3 weeks ago | [YT] | 198

David Malawey

An open source Lathe is a big undertaking, but it might inspire more participants and collaborating designers. Modulathe V2 is a free and open design by Max Kachurovskiy with youtube videos to support builders. I studied Max’s design and I’m publishing some elements that may support an Open Lathe V3 design.🤓

In 2025 I bought 2 chucks: 80mm and 160mm, and explored the spindles that typically pair with these. This month I bought a ready spindle - can you guess where the design comes from? This spindle has a cast aluminum housing and bearing OD of 52mm. It’s smaller than most lathes but fairly strong. I posted the drawing among the photos.

To me, a lathe head is made of torque, a motor to send it, a chuck to spend it, and a spindle to hold things steady. The other lathe half takes control of a tool and keeps it rigid. Right now i’m examining the head design.

[Design Questions]🤔
What’s the best way to couple the motor power to the shaft? What’s the simplest way to gain rigidity and alignment for the parts? What modules can be designed independently, so users can implement their own parts? You’ll find my DC motor is a costly large item while other users might want to use a smaller stepper motor or a brushless one. How to design a unit that allows different configurations?

If you’d like to participate along with me, I’ve posted 3 key CAD Models:
- Spindle design 🧵
- Chuck, 160mm 🗜️
- Chuck, 80mm 🗜️🗜️

Each of these are robust, cost-effective and high volume solutions that I’ll implement in one way or another. If different designers work with these same parts, we can co-develop solutions.

Skip the Carousel

1 2 3 4 5 6 7 8 9 10

1 month ago | [YT] | 401

David Malawey

My issue with the o-ring containers is spilling of the rings between dividers. 👉The root cause for this issue: sometimes o-rings cling to the lid. After this, the top cover has a gap that invites units to jump out of their spots, and if I get in a hurry, a lid won’t shut and the container dumps. 😳

The 🌟oRingPin 🌟modular pins resolve the issue. They fit flush with the lid, leaving no chance of spot-hopping parts. The next solution gives us holding of o-rings as a subset. I don’t want to carry the whole box all the time. Now we can grab a few sizes and bring them somewhere without spilling. 💼

Its NOW posted on grabCAD! (July 1). These free and open CAD files are part of OpenLab Project found at ✅qr.net/openlabproject ✅and resides on GitHub. Happy o-ringing!

Download Parts ► grabcad.com/library/oringpin-1

Skip the Carousel

1 2 3 4 5 6 7 8 9

1 month ago (edited) | [YT] | 333

David Malawey

[❓What should I name this design? 🤔❓]

I REALLY DIDNT WANT TO DO THIS but you can’t have the world’s most complete lab 🥼without a sensible organizer for your o-rings. 💍And the organizer isn’t sensible unless it’s adjustable.

So I designed a parametric spool thing to print various sizes and hold the o-rings. See the last photo for the next step: design a rack that holds several of these spools. Then we can stock one rack with a range (say 5-9mm) of o-rings and just grab that range while designing a part of this size.

[Self Study] Instead of making a ton of boring prints, I made a study of “vase mode” with my 3D printer and OrcaFlashforge. How does the slicer revise a solid model into an outline? The answers live in the images here.

🏺A successful Vase-mode part is built with one continuous extrusion from bottom to top, which can speed up a print a great deal. But it requires a compatible geometry. 🔑 Key Point: you must still export a part with solid mass and only one exterior contour given a vertical slice of the part.

🧠 Big Idea: Eventually I’ll have a list of custom organizers for openlab. Kinda like Gridfinity but a narrower range of parts and a boost in mechanical design. Having problem statements more defined, we can take community upgrades more effectively and converge on the best designs over time.

Skip the Carousel

1 2 3 4 5 6 7 8

1 month ago | [YT] | 241

David Malawey

These two pump units have volunteered to be example devices in OpenLab Project! 🔬🥼Both modules come from used outdoor products and they contain positive displacement types of pumps for water.

The first 5 photos show the pump⛽️ from my recent short video (electric pressure washer) and next 5 photos come from a gas powered Craftsman pressure washer. We can isolate the pumping modules and create special outcomes that move hydraulic oil or water or even yogurt (if you like that sort of thing).

It’s a big leap up from the $20 water pumps🐳 in my totes on the wall, and it’s necessary for our lab to be capable of “building anything we want” as Ive stated as my goal. And then to have an example and specifications for every type of actuator, followed by demonstrable applications.

Do you have another important actuator we should add to the list? ❓Dying to see a teardown with accompanying knowledge? 🙋‍♀️Im happy to receive parts by mail 📬and perform a teardown video if it fits in the lab!

Learn more at qr.net/openlabproject

Skip the Carousel

1 2 3 4 5 6 7 8 9 10

1 month ago | [YT] | 158