Author: Jan Mrázek

A programmer, who tries to do more than just a plain programming. Likes the computer science theory and at the same time the hardware and electronics. Masters student at FI MUNI and a member of the ParaDiSe laboratory, where works on software model checking. Hobby electronic and robotic enthusiast, an active member of RobotikaBrno. Designs robots and electronic gadgets for fun.
3D printing

Testing Siraya Tech Fast Mecha: A (r)evolution In Functional 3D-printing?

| Jan Mrázek

There are many resin printing materials out there marketed as “engineering”, “for functional parts”, “heavy-duty”. Since I got into the resin printing world, I tried a large number of them. However, none of them in my opinion didn’t deliver what was promised. The main challenges are not only low strength but also low impact resistance and most notably insufficient surface properties. Most of the 3D-printing resins out there are easy to scratch and when two surfaces mate, they have relatively high friction, and, most notably, they grind each other and form a white powder.

I was given the opportunity to test a new material – Siraya Tech Fast Mecha that claims to be suitable for articulated functional parts. The marketing is that the material doesn’t grind when two surfaces interact. Is it true? We will find out in this hands-on review. For clarity; I was given a sample of Siraya Tech Fast Mecha for free before it was available to the general public. I wasn’t paid in any other way for this review and all opinions are mine.

Continue reading “Testing Siraya Tech Fast Mecha: A (r)evolution In Functional 3D-printing?” →
3D printing

Overview of Practical Resin Properties

| Jan Mrázek

In this regularly updated post, I sum up the results of torturing various resins for SLA 3D printing. I have a very fine and functional mechanical model – a 1:85 compound planetary gearbox. The gearbox uses M0.5 teeth (half the LEGO gears teeth size). It is intended to be used with a brushless motor. The overall diameter of the gearbox is 38 mm. Here’s what it looks like:

Continue reading “Overview of Practical Resin Properties” →
3D printing

A Step-by-step Guide for the Perfect Bed Adhesion and Removing Elephant Foot on a Resin 3D Printer

| Jan Mrázek

In my recent blog post, I showed you that the resin viscosity and printer’s poor construction are the main reasons why people observe print failures. I also highlighted that the same phenomenon causes the elephant foot. However, I did not give you a step-by-step guide on how to work around it. I’ll fix this in this blog post, where I show you how to use UVTools to post-process your sliced files in order to get the perfect bed adhesion and no elephant foot on your prints.

I will show you how to get perfect results every time.
Continue reading “A Step-by-step Guide for the Perfect Bed Adhesion and Removing Elephant Foot on a Resin 3D Printer” →
3D printing

What Screws Does Elegoo Saturn Use?

| Jan Mrázek

There is a common question regarding damaged and lost screws on the resin tank on Elegoo Saturn. I have answered several questions for this on the Facebook groups, but those are not indexed by Google so you are out of luck when Googling. This is why I publish this really short blog post – so people can actually Google up the screws used on the Elegoo Saturn resin tank.

There are three screws:

  • M3x5 with countersunk head,
  • M4x10 with countersunk head, and
  • M4x10 with cylindrical head.
  • The vat is attached via M4x40 screws with overmolded cylindrical head.

This is it. I hope the search engines will pick this up well.

3D printing

Prints not sticking to the build plate, layer separation, rough surface, elephant foot: resin viscosity – the common denominator

| Jan Mrázek

When you scroll through the various Facebook group about resin printing, you see quite often questions about the following topics:

  • “my prints are not sticking to the build plate”
  • “my layers separate”
  • “my prints have a rough surface”
  • “I have a large elephant foot/squished bottom layers”
An example of all the problems shared in the FB groups. It is really not hard to find them.

In the first two cases, people often advise “increase your bottom layers!” and “increase your bottom exposure”, “lube FEP”, “sand your build plate!”.

But I think such advice is wrong and the best advice for all four cases should be “Introduce a light-off time”. Why? Let me walk you through a series of experiments and observations. It will be a long read, but bear with me – it is an actually simple puzzle just with multiple factors. And as we will see at the end, the same advice also applies to solving the rough surface case and also (partially) the elephant foot. We will also learn, that printing at layers thinner than 50 µm does not make much sense and it can actually degrade the print quality and precision.

Note that I have previously touched on this topic in my blog post Improving surface finish of hollowed SLA 3D prints: one aspect of blooming.

Continue reading “Prints not sticking to the build plate, layer separation, rough surface, elephant foot: resin viscosity – the common denominator” →
Electronics, Projects, Software

Panelization & automation for KiCAD made easy: KiKit v1 finally released!

| Jan Mrázek

After half a year I finally released version 1.0 of KiKit. You might ask – what is KiKit? KiKit is a tool for automation of the manufacturing process of your boards designed in KiCAD. It makes the process fully automatic, repeatable and less error-prone. It basically allows you to:

  • Create panels of your boards (without any limitations on board shape). You just run a command and that’s it. No more hand-drawing of panels!
  • You can quickly export files for manufacturing. KiKit comes with presets for various manufacturers, so you just invoke a command and you get the correct settings for gerbers, it can also export BOM and POS files according to the manufacturer specs. It can also check DRC for you and it does not generate any files in such a case. Therefore you never submit faulty gebers for manufacturing.
  • It can also export stencils – either files for manufacturing of steel stencils or it can export a 3D model of a stencil that you can 3D print.
  • You can automatically run DRC in CI hooked in your repository – in that case you will be notified via e-mail, that you committed something, that does breaks the board.

KiKit also simplifies some parts of the workflow, where KiCAD struggles – e.g., batch hiding of references or multi-board projects.

So what is new in the current release?

Continue reading “Panelization & automation for KiCAD made easy: KiKit v1 finally released!” →
3D printing

Testing 3D-printing service offered by JLC PCB on functional prints

| Jan Mrázek

About a month and a half ago I was offered to test the new 3D-printing service of JLC PCB (my got-to PCB manufacturer) before it was open to the public. They offered me 30 USD off the testing order, so I thought – let’s give it try! In this rather short blog post, I will give my impression of the print quality and service as a whole.

The test components
Continue reading “Testing 3D-printing service offered by JLC PCB on functional prints” →
3D printing

Hand-on experiences with Mercury X Washing & Curing station and 15 USD must-have upgrades

| Jan Mrázek

I’ve been in resin printing for over two years now. I have always refused to get a curing station. I disliked the available solution and was happy with my setup of several Lock’n’lock containers with IPA and a simple curing box made out of IKEA Lixhult. If you are wondering why I disliked the current solutions, read the ending of this post where I describe my dream machine.

However, my containers got small and I was considering getting bigger ones. It was at the time when Elegoo announced Mercury X pre-order. I thought “Ok, let’s give it a shot”.

I received my unit in September and I’ve been using it on a daily basis. Current experiences? It works pretty well and I am happy about it. I wouldn’t go back to my “dumb containers with IPA”. If you would like to see a full review that lists all the features and gives you the basic idea, please refer to other reviews: e. g., a nice review by Thomas Sanladerer.

In the rest of the post, I will show you what I dislike about the machine and how I improved it (at least a little) to make it suitable for heavy and convenient usage. Please note that overall I like the machine and I would advise my old me to buy it.

Problem #1: Only a single cleaning container

This is the biggest flaw of the machine – there is only a single container for IPA & cleaning. Do you ask why you would need more containers? It is more economical.

Continue reading “Hand-on experiences with Mercury X Washing & Curing station and 15 USD must-have upgrades” →
3D printing

A better way of making silicone components using a resin printer: Injection molding for less than 50 USD

| Jan Mrázek

Not so long ago I published a blog post showing how I make silicone components. If you haven’t read it I recommend you go through it first. I won’t cover all the steps for making the components — I will just discuss the game-changing improvements in my setup.

You might be asking what might be such a game-changer that it deserves a separate blog post. Previously, I designed open molds and pour silicone into them. Now I have found a way how to inject the silicone into a closed mold.

Injecting the silicone makes the whole process faster, cleaner, and also, more reliable (no more trapped bubbles!). On top of that, it allows me to design more complex molds which can, e.g., make removal a much more pleasant process.

Continue reading “A better way of making silicone components using a resin printer: Injection molding for less than 50 USD” →
3D printing

Easy procedure for saving LCD on MSLA 3D Printer After a Resin Leak

| Jan Mrázek

Resin 3D printers are awesome, however, the whole process is extremely messy. Especially when an accident happens and the resin leaks from the vat all over the printer.

When this happens mid-print, it usually means one thing – the resin will leak onto the precious LCD of the printer and cure. This means one thing – the UV light will be blocked by the cured parts and you will probably experience holes in your printed parts.

Usually, the people on Facebook advise you to scrape the resin away with a plastic razor. This usually works for small leaks, but it doesn’t work well on large leaks.

I experienced a resin leak recently on my Elegoo Saturn. Scraping the resin was not leading anywhere and I managed to scratch the polarizer film on top of the LCD. Therefore I stopped and I decided to make a (successful experiment): use acetone to dissolve the cured resin. It worked flawlessly!

The method is based on the observation that resin softens in an acetone bath, but the polarizer film seems not to dissolve in acetone.

Continue reading “Easy procedure for saving LCD on MSLA 3D Printer After a Resin Leak” →