Which do you prefer? I have the option to do both but milling seems to take awfully long and produces a lot of noise and glass fiber dust. It has the benefit of not needing etch resist which is also messy.

Chemical etching with iron chloride is also quite messy. First applying etch resist, removing part of it, etching etc. It is much simpler though and you don't need a CNC machine for this.

I made an enclosure for build-in induction cooking hobs. The build-in models are usually much cheaper and have better features than the free-standing ones. The corner blocks and ventilation grills are 3D printed and the side panels are 6mm thick aluminium composite plates. The plates are glued to the corner blocks using epoxy.

The price of the ACP plates and glue combined is still far cheaper than the difference between build-in and free-standing induction hobs and it's quite a simple model.

Here is the model and design file.

https://www.printables.com/model/1769315-induction-hob-enclosure

Normally you'd post a FixMyPrint issue where the OP asks for a solution. Here instead I post an issue and the cause/solution immediately as well, hoping that it helps others.

This issue looks this way in a CoreXY printer, on a Cartesian printer you probably have only one axis looking weird.

The top part of the image has two printed objects in it, they're corner blocks for an enclosure I'm making. The right one has a bend in it. The toolhead would consistently move 1mm to the right or left at the exact same location. Normally a layer shift occurs due to warping or loose belts or hitting the infill somehow.

The left block is what it's supposed to look like.

Upon closer inspection of my belts it appears that one of them was stretched a small amount. These are cheap generic belts from Aliexpress that did last quite a while but were probably not the highest quality. At some point the filling material breaks and the belt stretches by a small amount. When that part of the belt goes over the stepper motor you get a layer shift.

Now I got Gates belts and hope that they last longer.

This is an article from 10 years ago but so far I have not seen any 3D printers actually use this.

Currently I'm designing a new toolhead for my 3D printer and I want to make the footprint as small as possible to maximize the usable print area. I'm redesigning an Ender 5 so that the bed of an Ender5Plus fits into the frame of the Ender5 and that most of the area is accessible by the nozzle. The toolhead is one obstacle.

My current toolhead has two 5015 blower fans, one on each side, and they add a significant amount of bulk to the toolhead. The fan ducts are also quite bulky.

Have any of you tried a small aquarium pump with a length of Bowden tubing and perhaps a blunt syringe tip at the end? This way you can precisely direct airflow to the plastic flow and not cool the nozzle down too much, which is unavoidable with blower fans.

I'm thinking towards those cheap 5v USB aquarium fans that you can buy for a few euros from China.

I'm designing a new toolhead for my heavily modified Ender 5. At the moment it uses a MicroSwiss all metal hotend with dual blower fans, a tiny 404010 fan on the heatbreak (barely enough) and on top of it an Orbiter 1.5 extruder.

It has been working quite well but I want to get something with higher flow capabilities to push print speeds. Perhaps even dual Orbiter extruders and two hotends.

After I'm done modifying the Ender5 it will have a 314x314 bed which should allow for dual hotends without losing too much space.

Ideally I end up with a new toolhead so that the old one may be kept as backup.

I have been eyeing the Orbiter V2 with the Phaetus Rapido UHF but I'm open to suggestions. What have you been using and do you have any advice? There are a ton of options.

I want to start a DWC hydroponics system on my balcony but have concerns about the safety of the plant containers.

The first idea was to use plastic sauce buckets from the local snackbar. They're a waste product and you can easily get a large stack of 10L buckets for free just by asking. They're initially food safe material and all you have to do is wash out the sauce residue.

The problem is though that this food safety won't last long in sunlight. The plastic will inevitably break down and release contaminants into the plant water and therefore will also end up in whatever vegetables that are growing in it.

I have considered getting other materials, such as glass vases or perhaps stoneware. Both are heavy and anything large enough is also quite expensive. Weight is a consideration as well on a balcony.

Another option would be to cover the plastic buckets with some plate material with a few holes in it for the plants.

Am I overthinking this? I'm trying to avoid plastic whenever possible but with the right precautions it shouldn't be that bad.

I want to grow my own supply.

Hi, I'm trying to attach an ER11 chuck to a 775 motor to use as a spindle for my custom CNC machine. The machine is meant to make circuit boards so a 775 motor is good enough for that. Perhaps wood engravings could work too.

The issue is however, the chuck I'm trying to attach has way too much play when putting it on the shaft. The bottom of the ER11 chuck is not flat either so pushing it all the way down to the motor is not working.

The goal for this setup is to mill traces of 0.2mm wide. Perhaps 0.1mm if the V-bit allows for it so it should be on as straight as possible.

I have tried putting the chuck in the freezer overnight in an attempt to make the hole a bit tighter but that was not good enough.

Is there a good method to do this? I could just order a readily made 775 spindle from Ali but that seems a bit wasteful.

This is an idea that entered my mind. As far as I understood lithium ion batteries still need oxygen from the air to burn.

They don't provide their own oxidizer IIRC but they do reignite when left to dry because they rapidly build up heat again. Please correct me if I'm wrong.

Edit: I was wrong: https://www.sciencedirect.com/science/article/pii/S2352152X24008739

The cathode breaks down into oxygen among other things.

Would it make sense to have a lithium ion battery inside an airtight enclosure and fill it up with nitrogen? This way the only source of oxygen is from the decomposing cathode but that should react away quickly. The fire will be much less intense than in regular air. Assuming the enclosure holds.

Is this a silly idea? Is it even worth doing?

Is this feasible at all?

My idea is to have a battery of 112 Li Ion cells in series, ending up with a nominal voltage of about 414V. This is apparently how car batteries are configured as well and it's the easiest for an EGS002 inverter.

Charging however is quite difficult as stepping up to those voltages is not trivial.

The idea is to have a charge pump circuit on every single cell. 2 mosfets for charging, a capacitor, 2 mosfets for discharging. The capacitor would charge from a 4.2V supply and discharge into the battery.

The mosfets on the battery side can be controlled with optocouplers. The gate voltage is provided by cells further up in the chain so the gate always has at least 12V on it.

Is this a bad idea? Things that come to mind are the mosfet losses. Essentially the on resistance counts 4 times per cell but usually the rDS on is in the 20 mOhm range, so 80 mOhm per cell.

Balancing is much easier this way.

Perhaps a compromise that charges several cells in series and watches the balancing could work too if efficiency is the biggest reason against this.

I'm aware of the safety considerations.

What would be the best way to do this? I have made a 16s li-ion battery system and would like to build an inverter myself as well. For that I will be using an EGS002 module and according to the datasheet that requires a 400V DC source which will be converted into a sinus-ish waveform using sPWM.

I also see circuits online from dubious sources such as instructables that claim you can also apply the sPWM signal to 12 or 24V and then run that through a transformer for the same result. This is not in the datasheet, but does it work? This sounds like an easier setup. With my battery it would require a different transformer ratio.

Since I'm using a 16s battery the voltage will be in between 48V at its lowest and 64V at its highest. The feedback should be able to compensate for this.

As for transformers, I have a few 1:9 (European) microwave transformers, it would be nice if those could be used for this project as they're more than capable of big loads.

Ideally I would like to build an inverter that can provide 2000W of power, perhaps more. The whole idea behind the battery/inverter system is being able to power household objects when the power goes out. The ultimate goal is to troll my neighbors in that once in 5 year event.

Of course there is the commercial option, which I might use, but I want to learn how they work as well.

This is a design I'm working on. The idea behind the wave pattern is so that they can be stacked without losing all too much space compared to rectangular cell packs.

I'm putting a 60C thermal fuse in between each cell pair. Should a cell overheat, the fuse will pop and render the pack useless. This is an additional safety feature on top of a BMS and periodic manual checkups with a thermal camera.

The idea behind all cells pointing upwards (positive facing up) is also a safety feature. Should one start to vent or catch fire the flames will go up immediately triggering an extinguisher above the cell pack.

Let me know what you think! I'm not finished with it yet but if you want the design files already let me know I'll send them to you.

Edited with a deshittified version of imgur.