It’s been a few weeks since I got the laser engraver, and everything I ordered has arrived. Some things turned out differently than expected, as is often the case. In the first post about this device you can read what was planned. Ultimately, the following was implemented:

• Enclosure with smoke extraction and lighting*
• LONGER honeycomb plate*
• Air pump as air assist*
• Limit switches*
• Quick adjustment of the Z-axis

I didn’t install the cable chains:
After the enclosure and base made of OSB-reinforced chipboard had been properly installed, I noticed that the cable chains would not have had any room to roll out. Instead, I used Velcro cable ties to guide the cables. This works well, nothing drags or sags. In the meantime, some things have already been engraved and cut.

Endstops

It was surprisingly easy: I used LaserGRBL to check whether the latest firmware was flashed, which was the case. Then I mounted the purchased end stop PCBs on the 3D-printed brackets, extended and sleeved the cables and simply plugged them into the designated sockets on the mainboard, nothing else.

AtomStack Studio was able to reference immediately without any problems and the LEDs on the boards also light up when triggered. It first moves to the limit switches and then almost perfectly to the 0.0 position marked on the axes. Very good, I had imagined it to be more complex.

Enclosure and Air Assist

Not bad at all for the price. The fan is acceptably quiet and provides good airflow. The lighting is nice and bright. You can’t ask for more than that; I don’t really have anything to complain about. It was also super easy to assemble, and despite the simple design, the whole thing is surprisingly stable.

The air compressor wasn’t cheap, but you can tell:
Good build quality, vibration-isolated, and made of metal. It’s also tolerably quiet and very finely adjustable. I would buy it again.

The 3D-printed part for the laser head needed a little work, but then it fit well and works exactly as expected. No more smoke residue!

Current status

The notebook and compressor are located outside due to the smoke. I did not specifically seal the enclosure at the bottom of the plate, but no smoke escapes nonetheless.

Der Beitrag Upgrades for the AtomStack A5 Pro erschien zuerst auf flohs blog.

For my birthday today, I received a laser engraver/cutter, among other gifts. It is used but in good condition and complete, ideal for beginners. I’ve often toyed with the idea of getting something like this, but the areas of application are very limited – especially if you already own one or more 3D printers. Now I’ll probably have to deal with the topic head-on.

It’s an A5 Pro from AtomStack* with the following technical specifications:

Receive today and start using immediately?

Of course not. First, I looked around for a control option and revived a long-forgotten Lenovo ThinkPad X201 (8 GB instead of 4 GB RAM, Samsung SATA SSD, new thermal paste, Windows 11 Pro 25H2 installed). Once that was done, the laser was set up on a trial basis to test its capabilities:

It quickly became clear that something had to be done about the smoke.

Planned upgrades and modifications

I ordered the following parts:

• An inexpensive enclosure with suction and lighting*
• LONGER honeycomb pattern plate* measuring 440 x 440 mm, 22 mm high
• Air pump as air assist in a set*
• 10 x 20 mm cable chains* made of ABS
• Limit switches*

Until everything arrives, I’ll print more upgrades (in black PETG*):

• Air Assist (Thingiverse)
• End stops (Thingiverse)
• Dragging chain mounts (Thingiverse)
• Quick adjustment of the Z-axis (Thingiverse)

I will create mounting options for the laser and the honeycomb plate myself as soon as I have all the components and can take measurements. The whole thing will most likely be built onto a carrier plate, with the option of removing the housing quickly and easily.

Apart from that, the power-hungry components all run on 12 volts DC, which brings to mind the idea of using a central, powerful (Meanwell?) switching power supply instead of three different smaller ones. For 5 volts USB, then possibly a DC-DC step-down converter – that would make two power supplies in total, one for the ThinkPad and one for everything else.

Hardware / Firmware

In this case, it is convenient that AtomStack uses a standard motherboard that can do much more than the supplied firmware allows. At the moment, I don’t plan to expand anything except the end stops – but it would be possible by flashing a different firmware.

This board is installed:

Once all components have been delivered or printed, we will continue.

Der Beitrag A new toy arrives erschien zuerst auf flohs blog.

After using several of these AA Li-ion batteries for some time, we needed a way to store them sensibly. At the same time, it should be possible to charge the batteries in the intended holder, among other things to prevent short circuits caused by dangling.

After several revisions, we now have a number of holders in use, printed in gray PLA with green or black sliders (to indicate the charge status, black because I didn’t have any red available):

Downloads

Here are the STL files needed for printing:

Der Beitrag USB-C Li-Ion battery replacement for alkaline – charging and storage holder erschien zuerst auf flohs blog.

There will be several places in our house where it would make sense to install a flush-mounted multimedia channel*. We are planning to install channels measuring 1.5 to 2 meters in length, with end caps at both ends. The following locations are being considered:

• Living room
• Bedroom
• Workshop
• Dining room
• Kitchen
• Computer room

So, assuming 2 meters, we need more or less 12 meters of ducting. In reality, it will of course be a little less; in the workshop, for example, the ducting will only be about one meter long. After doing some research, I found that the ready-made sets were either suboptimal or very overpriced.

What to do?

While searching for alternatives, I repeatedly came across the idea of simply using a flush-mounted ventilation duct on several blogs and websites. These ventilation ducts have grooves on the outside, which makes plastering or fastening them much easier. However, the inner walls are smooth, which makes them ideal for use as cable ducts. In addition, the material can be easily cut to length with a utility knife and the necessary cutouts can be made later with a hole saw.

I immediately liked the idea, but there was one catch: these ventilation ducts are expensive and can only be purchased in large quantities by private individuals. Fifteen meters would have been ideal for us, with a little leeway for mistakes or new ideas.

⧉ Zehnder

⧉ Zehnder

⧉ Zehnder

I didn’t find that, but I did find a dealer who sold me 20 meters of Zehnder Comfotube 51 flat, including shipping costs, for just under €300, which works out to just €15 per meter, which seems downright cheap considering the available solutions.

I 3D-printed the end caps from PLA and glued them into the pre-cut channels with acrylic. The finished channel can either be fixed in the wall with PU foam or filled in with multiple layers of filler. I filled it and, after plastering, simply drilled the necessary holes through the plaster into the channel at the previously marked points using an 83 mm hole saw*. I then glued 3D-printed bushings into the wall using silicone and later screwed or plugged a “hole cover” into them.

Conclusion

The result is great, better than any ready-made solution could be AND also significantly cheaper. I also have a lot of flexibility with the duct dimensions. In the computer room, for example, the duct does not run from the installation height above the floor to approximately the middle of the room, but instead from the ceiling to the middle of the room, as it will be supplied from above.

I first came across this solution on 100prznt.de. Thank you very much for the great idea—unfortunately, the site is no longer available. However, this solution has also been chosen in other places.

Downloads

I am providing the STL files for the parts I created here, including the end cap that originally came from 100prznt.de – unfortunately, it is no longer available there. If this is not acceptable, please send me an email and I will remove this file, of course:

Update from January 14, 2026:

The original files for the end cap can still be found at Printables from the original creator!
However, the original bottom of the website is still not functional.

Der Beitrag Flush-mounted multimedia channel, but good and inexpensive erschien zuerst auf flohs blog.

The original plan was to simply screw the bench drill to the workbench and that would be it. However, the PBD 40 has openings in the aluminum base which dirt can and will inevitably fall into the hollow base.

Then another idea came to mind: similar to the bench grinder, build a base and integrate a drawer into it. Also mostly made from 40 mm multiplex scraps. No sooner said than done: this is what the result looks like now:

Except for the “front panel,” the drawer is simply made of leftover laminate without integrated impact sound insulation (MDF slides well!) and is fixed with 3D-printed brackets using M3 countersunk screws. After working with the machine, you can now simply sweep the dirt through the openings in the base and remove the drawer from time to time to empty it conveniently.

Der Beitrag A dirt trap drawer for the Bosch PBD 40 erschien zuerst auf flohs blog.

I purchased a Bosch bench drill for our workshop – a PBD 40. The data sheet looks good, and I bought this tool second-hand, but I had some reservations before purchasing it:

You often read that the accuracy leaves something to be desired, especially when drilling small diameters in metal. It was clear to me from the outset that if I bought this model, I would immediately convert the internal bearings to something more precise.

That’s why buying second-hand made sense; I didn’t want to be restricted in my actions by a warranty period and preferred to invest the money I saved on the purchase in the conversion. Alternative bench drills, e.g., from Scheppach* or Parkside, don’t really offer much more, and I can’t imagine that they are any more accurate. That’s why I opted for Bosch, even if it’s “only” Bosch Green (for private use, not commercial).

Upgrade

First of all: There was a really interesting and useful thread in the official Bosch forums about which bearings are suitable and how to convert the whole thing.

Unfortunately, it seems to have been deleted in the meantime; at least, I can’t find it anymore. If I come across the content in the future, I will add it here, but unfortunately that seems unlikely. Things can disappear so quickly!

The precision bearings used were these two from Kugellager-Express.

Disassembly and reassembly is quite easy to do. Simply remove all visible screws until you have taken the gearbox apart. Be careful with the cables and plugs, as these are often quite short.

The most difficult part is removing the pressed-in bearing in the aluminum housing; even with an internal puller, it took me several attempts. Photos:

Conclusion

The observations made by the original posters of this conversion were not exaggerated: the concentricity and drilling precision have really improved considerably, even with the original drill chuck, which is often described as “poor”!

There is virtually no noticeable play anymore. Anyone who owns a PBD 40 and is dissatisfied with its precision should carry out this conversion; I am very satisfied.

Der Beitrag Bosch PBD 40 bench drill: Increase accuracy erschien zuerst auf flohs blog.

For our workshop, I wanted a bench grinder* that, unlike most, was equipped with a wire brush on one side instead of another, coarser grinding wheel. This poses a problem: a significant imbalance, as the grinding wheel is much heavier and more round than the wire brush.

Regardless of this, a bench grinder is generally a vibrating machine. In my “old” makeshift workshop, there was an older bench grinder with two fairly well-aligned, smooth-running grinding wheels – also screwed to the worktop. Even when starting up, the entire worktop vibrated, let alone when you held something against the wheels with force to grind it.

In our “new” workshop, which is built into the house, I wanted to avoid the problem from the outset, or at least minimize it significantly.

How do you do that?

I had already had experience with so-called “rubber-metal buffers” in the past to decouple a two-cylinder air compressor. It worked so well that it was hard to believe:

The mount on which the compressor stood at full operation basically no longer vibrated, which made everything much quieter. So my first thought for this grinding block was similar – rubber-metal buffers.

Implementation

It’s actually quite simple: First of all, I should mention that I am relatively tall, so a “foot” that raises the bench grinder is very useful for me. This is how I did it:

• Two pieces of 40 mm multiplex cut to size and sanded
• Holes drilled and countersunk in the lower of the two panels so that they can be screwed to the worktop later
• Recesses drilled from the other side so that self-locking nuts can be pressed in to hold the upper panel in place
• Using a 25 mm Forstner bit, cylinders approx. 10 mm deep were drilled into the upper panel so that the buffers could be made to disappear almost completely
• Suitable through holes were drilled in both panels for all screws

I used 20 mm buffers with internal threads on both sides (Type C, Ø 20, Height 20 mm, IG/IG M6, NK 55 (20-20-C)*), with galvanized 8.8 M6 hexagon socket screws* and lock washers both from below (invisible) and from above to secure the grinding block.

Experiences

The decoupling is not 100% effective – slight vibrations can still be felt. This is particularly noticeable because we keep our storage systems for screws etc. on the same worktop – you can feel and hear even the slightest vibration.

Nevertheless, the result is really good: 99% less vibration.

Photos

You can clearly see the gap between the plate and the machine; light shines through the gap.

Der Beitrag Decoupling the bench grinder – Scheppach SM200LB erschien zuerst auf flohs blog.