Y-Piece

[Peuqui]

Hello,

I am totally new to Fusion 360 and trying to reconstruct a design, that I need for our hospital as personal protective equipment.

At our Intensive Care Unit, we need better protection at high risk procedures like in-/extubation, tracheotomy, etc. Despite the shortcoming of FFP3-masks, we decided to use the Subea 500 Snorkelmask from Decathlon as described in various documents and website all around the world for a better protection. An adapter with two 25mm ISO-connectors made from Filip Kober (https://grabcad.com/home/inbox/7650461) fits onto the Version 1 mask, which is outdated and not manufactured anymore. The version 2 mask (see above https://www.decathlon.de/p/schnorchelmaske-easybreath-500-oyster/_/R-p-148873?mc=8491266&c=BLAU_T%C3... ) lacks a special adapter with these two hose connectors. Filip provided for this newer model only an adapter with one connector as shown in the attached files.

I tried to construct such an adapter in Fusion 360, but due to my lack of knowledge, I wasted instead more than 30 hours in internet recherche, tutorials and trial and error without any luck.

I tried to contact Filip, to develop a version we are in demand or to send me the original CAD files. But due to the hurry of the situation, I decided to ask here for a solution too. And for me and my learning curve in CAD it would be better to understand, how to do it myself, instead of just printing given designs 🙂

My trials and errors so far below:

1. approach: Import the STL files into Fusion, cutting out the needed part of the version 1, cutting out the part adapter part of version 2 and try to merge them after and before converting them into BREP-> fail due to lack of knowledge after hours of reading tutorials and the like
2. approach: Using the STL file of the adapter part of version 2 as a template with Splines to get the correct shape. Then trying to extrude/sweep/and other stuff to get a workpiece like in the attachments. -> fail again
3. and some other attempts I superimpose the cloak of silence. 😉

So, I hope the community can teach me, how to do it properly.

[TrippyLighting]

No, I did not!

Thanks for checking into it.

In the past, this has only happened when instead of deleting messages I moved them into the Junk folder. Mac mail then starts recognizing such messages as Junk. However, that is not the case this time. I don't seem to get any messages from the forum.

[Anonymous]

@Peuqui  Filip thank you and says all the best to you too, from what I read he is very happy from your work and that you consulted almost everything with him.

A healthy person can breath out up to 100-102 cmH2O, I left some margin, data was taken from here:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1501025/

Soon I will have silcon seals and we're hoping it will be enough. I see you know everything already so thank you very much for your work and time you spend on this project. All the best. 🙂

Kind Regards

Łukasz Napora

https://respire.pl

[Peuqui]

45 mins ago, I received a message directly from Filip: he allows us to do so and said, it was the best way we reacted that fast to the demand. His remark to not re-engineer it, had the intention to not allow industrial production. 3D-Printing is not the problem.

If you, Peter, have nothing against it, I ask Filip, if he will include the STL file into his repository after we tested it thoroughly.

[TrippyLighting]

I would actually suggest that we include the file in .stl AND in at least in a neutral CAD format if not also in the Fusion 360 file format. It would have been difficult to create this geometry when working purely with .stl files (triangulated meshes) and having a CAD format available would make future efforts much easier. 

Thanks for the feedback and hopefully your efforts are helpful.!

[Peuqui]

That would be perfect and reflects the spirit of open source! 😀

[Peuqui]

This morning my printer spilled this out:

[Peuqui]

At the moment I can't test it with the Subea 500 mask (Version 2), because I gave it to a colleague, who is in need, meanwhile I am in holidays and don't need it urgently 😀. So I can concentrate on evolving this awesome idea and can be part of a worldwide iniative => love that! 😊

I ordered a new mask three days ago, but Decathlon is in holidays too and can deliver (hopefully) next wednesday. Maybe I bug my colleague during easter for testing...

Wish you all good and happy easter and God's blessing!

Markus

[brianrepp]

@TrippyLighting - are you still not receiving notifications?  If so, it's possible this is because forum email notifications switched over to come from a new email address "[email protected]".  Any chance these are getting caught up someplace in a rule or filter?

[TrippyLighting]

@brianrepp No, I don't, not even for private messages. When did the change to this new email happen?

This should not really affect the receipt of emails. The Smart email folders work more like filters and if a rule does not apply the filter just does not work, but it does not affect the receipt of emails.

However, coincidentally yesterday morning a macOS update dopped/autoinstalled and I am wondering now whether that included an update to mac mail that changed "something" hmmm ...

[Anonymous]

PERFECT!

@Peuqui 

If you printed this on 3D printer you MUST check if it's leakproof.

Close this adapter from both sides and push 0.13 BAR pressure into it, if it's holding that value adapter is good to use, if not its faulty.

This is very important.

0.13 bar - around 120cmh2o for a healthy person

[Peuqui]

I hope, you had a happy easter!

The adapter itself is leakproof, but, while the adapter and the venturi nozzle is FDM printed, it is very necessary to sand and smooth the surfaces of the connectors to ensure a tight and leakage free fit. It turned out, that making the connectors slightly tapered off to a point, the fit is much better. To this effect, I redesigned the ISO connector of one venturi nozzle and got a much tighter fit!

In one of my pictures I added a venturi nozzle on top of one filter. During my tests with the mask, it turned out, that the longer one wears the mask, the more sweating appears (who thought about that! 😧 ). So we tested, how we can improve comfort: After stacking this venturi nozzle onto one filter, applying an O2-/Airflow of approximately 10-15 l/min, we got a nice and soothing air flow, prevent sweating and cools down inside the mask. For working at patients, the attached O2-hose can be lengthened as needed to provide a comfortable range.

Meanwhile, I redesign (yes, my skills in Fusion360 improved greatly since my first impact in this forum! 😁) and print some different configurations of a venturi nozzle to optimize manufacturing process, i.e. optimizing FDM-printing to reduce print time and needed support structures as well as optimizing the air flow, because, whilst my printer isn't really bad at printing accuracy-wise, the original designs of the venturi nozzles with tough specifications regarding their dimensions, may not comply with the accuracy of my printer. Now, after printing a bunch of different samples, I'm going to test them in my clinic with our medical technician.

Hopefully, I get my new version 2 mask (Subea 500) soon, to test the fit of the adapter and get this design ready. (Hopefully it IS already ready 😀)

Best regards,

Markus

[Peuqui]

After extensive printing and testing, I come to this solution, which turned out best:

You just have to be cautious in forest...

[TrippyLighting]

LOL. You just need to be careful that you're not going to bang into door frames with these ... antlers 😉

Glad to see this works!

[Peuqui]

Hello Peter,

today, I got a breakthrough!

I was able to reproduce your building steps of the adapter. So , it was possible to modify the ISO connector to an inner diameter of 22,2 mm without problems, which turned out best to fit the filters and an outer diameter of 25,7 mm to reduce wall thickness and therefore print time. Wall thicknes of about 1,75 mm is far enough for a strong workpiece. My former trials of modifying were successful, albeit the approach was aweful. With a beginning understanding of the surface related approach, it is much more elegant! I learned a lot about using Fusion360 while researching your work step by step.

This moment, my printer is working the test sample and when its finished and satifies my need and requirement I would go and release it to the public. Maybe in Filip Kober's repository at grabcad.com.

Despite that, I am working on the design with the "plug shaped" pieces inside of the adapter. These thingies, which you ask, if they are necessary. Maybe they play a role in blocking CO2-revertive-respiration (dunno, if this word is correct...). So, it could be, that with them in place, less CO2 is back breathed due to reduced trapped volume.

But first, I have to manage the redesign of the adapter and do extensive tests after that. I think, it would be possible to cut and paste and do a few tweaks here and there to include these "plugs" into your adapter design. (Hopefully 😁) In a test session, I was able to draw such a design, but with my crude technique. Now I change to the surface modelling for more elegance...

Meanwhile, the present design works!

Many, many thanks for your effort and kind and fast help, Peter!

Greetings,

Markus

[Peuqui]

Hello Łukasz,

I would like to know, what kind of silicon seals you mean and where to place them? And then, where to buy...

Regards,

Markus

[TrippyLighting]

Markus,

Thanks for the feedback! I am glad you've been able to produce the desired result and also have learned to model with surfaces.

Working with surfaces can be a bit more work, but it allows us to create shapes that cannot be achieved with pure solid modeling.

[Peuqui]

Hello,

I modified your original design in two following ways:

1.)  I enlarged the connector holes up to 22,2 mm to better fit the filter connectors.

2.) as a second version, I added the plugs, I mentioned earlier. A drawback is, it has to printed with supports.

After some testing with the professional equipment of out medical technician, it turned out, that CO2-rebreathing is less with these plugs compared to the version without them measured on top of the filters. Which leads to the assumption, that the dead space inside the mask is reduced due to not (entire) filling the side pipes inside the mask, which are originally designed to lead exhaled air through the snorkel. While breathing under normal air pressure conditions, aka outside of water, without these plugs this exhaled air is rebreathed during inspiration, which leads to slightly raised CO2-intake.

I tried to maximize the middle hole for maximum air flow during inspiration.

In my opinion, these two solutions (the original Y-Piece with 22,2 mm connectors and the one with the additonal plugs) are now ready for publishing.

Nevertheless, my design pathway is far from elegant, but it lead to an acceptable result. Due to my lack of knowledge, I had some problems with the construction history. I had to shut it off for some reason.

If you don'nt mind, I would send these two designs to Filip for integration into his repository, if he wants to do so. But due to my messy pathway (and due to my lack of knowledge, I would like to ask, if you want to look over it, before publishing.

When we only publish the STL-files, its no problem with my construction path, because, it is not published in it. But when we decide to include the Fusion CAD-files too, I have to reconstruct it in a better way.

Please reply your opinion about it.

I'll send the files per p.m.

Regards,

Markus

[Peuqui]

Filip Kober added a cool solution for sealing the sidepipes of the mask, aka exhale pathways: he added a set of corks to his repository, which can printed separately if needed and the normal Adapter is plugged over it:
https://grabcad.com/library/printable-ventilator-free-respiratory-subea-easybreath-mask-adapter-1

This moment, I am printing the corks and when our newly designed Y-Adapter fits over these corks, I abandon the further development of the Y-Adapter with the integrated corks, as they displayed in the former post.

Meanwhile, I asked Filip, if he wants to integrate Your great design into his repository as we talked about...

[TrippyLighting]

I'll look at the updated design you shared with me over the weekend an provide feedback.

[Peuqui · Accepted solution]

Sweet!

Meanwhile the printed corks are ready and fit perfectly into the exhale paths of the mask. Unfortunately, our Adapter doesn't fit onto this. So, I have to redesign the Y-Adapter, that they fit together smoothly...