Berd-Air pump configuration notes for Duet users

Hergonoway

Thinking about getting a bigger tube, for the same obvious reasons, air flow. 3,75mm is kind of uncommon did you have to flattened the tube (I think of using 1/8" because 4mm seems to big) ? And did you use a jig to bend the "circle" part?

ayudtee

@hergonoway 1/8" is an improvement to the stock tube and is close to 3.75 (3.18). I flattened the tube by stripping a length of #12 AWG stranded and inserting as many wires as possible into one end. I flattened the end with a small hammer and pulled out each wire with pliers afterward. I am not using a circle, only the flattened tip.

timcurtis67

@hergonoway said in Berd-Air pump configuration notes for Duet users:

@ayudtee
And did you use a jig to bend the "circle" part?

One way to bend soft tubing is to fill it with salt (table salt) and tape the ends shut. Pack it pretty tight and then you can bend it to as tight a circle as you need.

Then remove the tape and tap it until all the salt comes out. I blow air thru it as well afterwards.

Hergonoway

@ayudtee said in Berd-Air pump configuration notes for Duet users:

@hergonoway 1/8" is an improvement to the stock tube and is close to 3.75 (3.18). I flattened the tube by stripping a length of #12 AWG stranded and inserting as many wires as possible into one end. I flattened the end with a small hammer and pulled out each wire with pliers afterward. I am not using a circle, only the flattened tip.

@timcurtis67 said in Berd-Air pump configuration notes for Duet users:

@hergonoway said in Berd-Air pump configuration notes for Duet users:

@ayudtee
And did you use a jig to bend the "circle" part?

One way to bend soft tubing is to fill it with salt (table salt) and tape the ends shut. Pack it pretty tight and then you can bend it to as tight a circle as you need.

Then remove the tape and tap it until all the salt comes out. I blow air thru it as well afterwards.

Thanks I'll give a shot then !

One last question, did you choose a specific angle for the holes ? some people keep the same 90° angle but others use a 45° angle toward the hotend, is there really a benefit from one to another ? the current problem I have with Berdair are on overhang, I've gain airflow by directly connecting the 1/8" tube to the aluminium tube, and I'll certainly gain more air flow by increasing the metal tube, but does orientation in this little space will change anything, I don't know.

ayudtee

@hergonoway My 2 printers are using an E3D V6 and an Ormerod Quickset II hotend. I do not have enough room under either hotend to use a larger tube that is bent in the stock ring configuration. A larger tube would not fit under either hotend after if it was bent into a circle.

Hergonoway

@ayudtee Standard E3D nozzle has a clearance of 5mm between the tip and the heatbock. I suppose your using these ones.

In my case I'm currently using tungsten MakerBot type of nozzle which have ~8 mm of clearance, so 1/8" should work with a E3D sock, at least I hope from my test on fusion 360.

I'll post pictures if it works #FingerCrossed

DocTrucker

Where in are people buying these systems in the UK?

ayudtee

@doctrucker Do you have access to AliExpress?

DocTrucker

Never used it, no. Had a look at a couple of the shared links to that site and they were for vacuum pumps rather than posative pressure pumps with warnings about significantly reduced life spans if used to generate posative pressure?

c310

@doctrucker

recently i have ordered this one https://www.aliexpress.com/item/Aiyima-Micro-Vacuum-Pump-DC12V-24V-50Kpa-Low-Noise-Large-Flow-Splitter-Separator-Diaphragm-Suction-Mini/32862878409.html?spm=a2g0s.9042311.0.0.7bf64c4dkxuMgA

24v pump, but not tested it yet... it looks like berd-air one.

Hergonoway

@msquared

Just set F25500 and it damn quiet now thanks for the tip.

But adding a thermistor (the ref given by DC42) in series doesn't work at all, at least for Berdair 24v pump.

dc42

@hergonoway said in Berd-Air pump configuration notes for Duet users:

@msquared

Just set F25500 and it damn quiet now thanks for the tip.

But adding a thermistor (the ref given by DC42) in series doesn't work at all, at least for Berdair 24v pump.

I guess that pump doesn't draw enough current to heat the thermistor up. There is probably another thermistor in a smaller size that would work. I'll order a few different types and test them.

Hergonoway

@dc42

thanks for your help ! unfortunately my multimeter is broken, I can't give additional feedback for the moment.

coredump

So, did anyone try the high frequency PWM with a module like this?

In my test here, using F500 and keeping the pump running at 30-40% gave me a lot of air, and not a lot of noise (I am using this on both intake and outtake), but the F25000 took away my ability to control the pump speed and sounds a little higher. I haven't tested temperatures yet with the two different F values.

I wonder if I should try to connect the pump directly to the DuetWifi. If there's not a lot to gain from that change in the noise department, I think keeping the module makes it safer.

BenDiesel

Have you cracked one of the mufflers open to see how it works?

coredump

@bendiesel unfortunately they are all one piece injected plastic, so it's not trivial to open.

They definitely lower the noise tho.

Responding my own question: that mosfet module that I added definitely blocks the high frequency PWM trick. I took a chance and connected the 24v pump I got from markerhive and connected it directly to my duet wifi (1.02) and with the highfrequency PWM I can run it at 20-30% with minimal noise.

Lets see how many fan ports I burn on this tho

coredump

This post is deleted!

coredump

@hurzhurz said in Berd-Air pump configuration notes for Duet users:

@msquared About the flayback diode, your link points to a 1N4007.
I have first tried this one, but it got pretty hot.
After some googling I think the reason is that the diode is just too slow for a high frequency of 25kHz (reverse recovery time of 30us).
I have replaced it by a schottky diode that doesn't get warm.

Are you using a 1N4148 or something different?

hurzhurz

@coredump
I'm now using a MBR345 as this was the first schottky diode I got into my hands after I read that schottkys are probably more suitable for higher frequencies.

And by the way, I have reduced the frequency to 20kHz so the mosfet stays a bit cooler.

fma

About the noise your are talking about, is it the PWM frequency you can ear, and so it disappear at 20kHz, or is it something else?