topic Re: Y-Piece in Fusion Design, Validate & Document Forum

Y-Piece

Peuqui — Tue, 07 Apr 2020 16:39:29 GMT

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ISO-connectors made from Filip Kober (https://grabcad.com/home/inbox/7650461) fits onto the Version 1 mask, which is outdated and not manufactured anymore.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%83%C2%9CRKIS ) 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:

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
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
and some other attempts I superimpose the cloak of silence. 😉

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

Re: Y-Piece

etfrench — Tue, 07 Apr 2020 18:25:19 GMT

Your Grabcad link doesn't work. Try attaching your Fusion 360 file (File/Export/Archive file *.f3d) to the thread. Attaching the stl's will also help.

Re: Y-Piece

TrippyLighting — Tue, 07 Apr 2020 19:54:44 GMT

This is easy to do, however, I don't quite understand what exact adapter is needed and have t0 puzzle this together form your post. The correct GrabCAD link seems to be this one.

But judging by the images you attached to the post you want this with 2 hose connections (thus the Y-piece) instead of one?

Re: Y-Piece

TrippyLighting — Tue, 07 Apr 2020 20:53:45 GMT

I'll take that back. This isn't easy to do.

The curves are not circular fillets.

Things have a slight taper to it (hat makes sense given the use case)

But I am on it!

Re: Y-Piece

Peuqui — Tue, 07 Apr 2020 21:52:57 GMT

Thank you very much for your investigation about this!

Yes, this link is correct! Sorry for the incorrect one and my fuzzy description...

The adapter he made as an "old" one for the Subea mask version 1 is perfect in my opinion and fits our needs very well but doesn't fit on the newer version of the mask, which we prefer after intensiv testing of both masks. Unfortunately, he discarded this Y-piece-type connector from his actual archive.

I attached the STL file of the old mask version 1 with the two connectors as an "Y-Piece". These connectors have to be ISO 5356 with inner diameter 22mm (and outer diameter 25mm). So we can connect two HME filters in the correct order directly onto the Y-Piece. The HME filter has to the patient side 22 mm male connector and to the respirator side 25mm female

In time, I got in touch with Filip and I hope, he can help with that too.

I am really thankful for your reply and hope that we find a solution!

Despite that, I am eager, how to do that myself 🙂

Again: thanks to all, who contribute!

Keep healthy and God bless you

Re: Y-Piece

TrippyLighting — Wed, 08 Apr 2020 00:12:54 GMT

Can you explain if these interior features framed in red are needed?

If so, your design approach would not work as it would eliminate those.

The original piece was injection molded and has drafts for demolding on every surface. That makes this less than straight forward to re-create.

The first image is an overlay showing both, the original mesh model and the re-created solid model.

Re: Y-Piece

Peuqui — Wed, 08 Apr 2020 08:23:27 GMT

Hi Peter,

thank you very much for your fast reply and hard work!

In my opinion is your last approach more than sufficient, because we need as much airflow as possible. These blocking frames at the side, as far as I understood this, is for the exhale airflow under water. Out of water, the exhaled air goes through the chin valve in the bottom of the mask. So, these structures are irrelevant for the adapter and can be omitted. I tested the original from Filip with an Y-Piece plugged onto the single connector version and noticed a significant reduction in airflow compared to the version in the STL file I attached. So, the integrated Y-Piece is that we are hunting for.

Thanks in advance and am looking forward to print and test it!

Re: Y-Piece

Peuqui — Wed, 08 Apr 2020 11:06:11 GMT

For more information, I post an evolving document about, what we are talking:

https://docs.google.com/document/d/1J22le3dBZBnNDXGlJLRb38z7v7LaOjKfDeN9f0tFeKY/edit#heading=h.kbdc4jqikxwz

Re: Y-Piece

TrippyLighting — Wed, 08 Apr 2020 16:02:12 GMT

OK. Here's what I have so far:

The way this is modeled lends itself to 3D printing, but its' not suitable for injection molding.

Here is a link to the 3D model at this time for viewing only.

One of the documents that is part of the GrabCAD files (Easybreath >> ISO 5356 – Filip Kober (rev. 7) )

states that "Moulding or reverse engineering forbidden."

Reverse engineering is what I've done with the two .stl files. How can I be sure that this model is only going to be used as intended by the original author ?

Re: Y-Piece

Peuqui — Wed, 08 Apr 2020 16:42:38 GMT

Hi Peter,

As you mentioned it, I reread this document too ("Moulding or reverse engineering forbidden.").

Sorry for your hard work so far and my fault not reading carefully before posting a request!

I will ask the author Filip Kober about it.

Maybe he permits your approach and/or includes it in his repository...

While the question to Filip is going and his answer pending, I would like to ask, if it is possible to round the marked structure as it is in the adapter of the version 1 mask?

I will inform you, when I got an answer from Filip. If he has no objections, we go further on, OK?

Best regards,

Markus

Re: Y-Piece

TrippyLighting — Wed, 08 Apr 2020 16:47:26 GMT

For whatever reason, the image does not show/download. Can you try and embed it using the large camera button above the text field when editing a post?

What is the reasoning behind the "rounding"?

Edit: I see the picture now and it answers my question. Yes, I'll proceed with that.

Re: Y-Piece

TrippyLighting — Wed, 08 Apr 2020 17:31:59 GMT

Done!

Re: Y-Piece

Peuqui — Wed, 08 Apr 2020 18:40:07 GMT

Awesome!

We wait for Filips answer and then we see, how we can deal with that.

Thank you very much for your great effort!

Best regards,

Markus

Re: Y-Piece

Anonymous — Thu, 09 Apr 2020 14:13:54 GMT

Hi. I'm speaking with Filip often. Filip posted this as free for non-commercial use, you are free to modify the project.

Ping me when u release your adapter so we can test it.

For both versions:

https://grabcad.com/library/v1-v2-easybreath-decathlon-subea-iso-adapter-rev-7-1

Respirator EQ ISO5356 (Y piece here)

https://grabcad.com/library/iso-5356-for-breathing-equipment-respirators-1

Venturi Valve

https://grabcad.com/library/respirator-free-reanimation-venturi-s-valve-rev-4-1

@Peuqui

Regards,

Łukasz Napora

https://respire.pl

Re: Y-Piece

Anonymous — Thu, 09 Apr 2020 14:23:06 GMT

@TrippyLighting You need this piece because the valve does not hold and when using mask for about an hour the DAR filters are wet and useless and also CO2 is gathering at the bottom of mask because it's heavier than air. This solves the problem. Other way is just to duck tape it.

You must test all 3D printed equipment at least using 120cmH20 or 0.11/0.12 BAR pressure (compressor and under water, see if its bubbling, if yes - trash it, if not - ready to use for medics).

Also one of our valued members pointed out that sides are too thin to print it FDM. He worries it will not hold.

@etfrench @Peuqui

Re: Y-Piece

Peuqui — Thu, 09 Apr 2020 14:24:26 GMT

WOW! that are awesome news! Thank you very much and tell Filip I wish him all best, because he isn't responding to my pm. Surely he is very busy.

Thanks alot to all, who are involved!

Best regards,

Markus

Re: Y-Piece

Peuqui — Thu, 09 Apr 2020 14:50:50 GMT

I think, you mean the O-Ring under the chin valve to tighten it up during inspiration, right?

In this setting, CO2 isn't gathering at the bottom of the mask due to turbulences induced from respiration.

We tested this mask thoroughly: my colleague is anesthesiologist and scuba diver too and for us, the mask seems tight enough for use as a PPE. During slow inspiration, there might be some leakage. Maybe we can seal it with that O-Ring. My printed adapter and Y-Piece and other stuff was tight enough for anesthesiology purposes. The leakage was negligible. But I will do further testing with our medical technician and our ICU-respirators.

You must test all 3D printed equipment at least using 120cmH20 or 0.11/0.12 BAR pressure (compressor and under water, see if its bubbling, if yes - trash it, if not - ready to use for medics).

Our anesthesiology equipment (respirator, tubes, connectors) are tested with a pressure of max. 30 cm H2O on a daily basis and is allowed to have a leakage of 50 ml/min. So, I don't know, where the 120 cm H2O comes from. Maybe it is for the test procedures of the manufacturers for a greater security zone?

Also one of our valued members pointed out that sides are too thin to print it FDM. He worries it will not hold.

The wall thickness of my print samples (Infill 100%) is from 1,6 to 2mm and all are pretty durable.

Best regards,

Markus

Re: Y-Piece

TrippyLighting — Thu, 09 Apr 2020 15:27:49 GMT

@Anonymous @Peuqui Judging by the images in Filip's documents his parts are made from PAEK. I don't know the mechanical strength of PAEK. This model was created based on the .stl files provided earlier in this thread and those parts of the geometry, which will provide the sealing interface to the mask should be within +-0.02mm of the .stl files.

However, the dimensions can easily be changed within reason to adapt better to the mask and/or to provide more strength in areas needed.

As I understand it, the ISO connector needs to be 22mm inner diameter and for the mask connection, the inner surface is the important geometry. As such the outer surfaces can simply be offset a bit more if more wall thickness is needed.

Here is a password protected link to the model. It can be downloaded in a variety of formats, including the native Fusion 360 .f3d file format including the construction history.

I'll share the password with @Peuqui

@Anonymous I can share with you as well if you wish.

@brianrepp I did not get any new post notifications for the new posts in this thread since yesterday ... Is the Forum still healthy (hopefully you are!)?

Re: Y-Piece

Peuqui — Thu, 09 Apr 2020 16:30:58 GMT

Hi all,

thanks again for that work!

I downloaded it and print it immediately.

Markus

Re: Y-Piece

brianrepp — Thu, 09 Apr 2020 16:31:21 GMT

@TrippyLighting - I'm here and healthy, hope you are too! 😀 Let me check in with the moderator team, I'm not aware of any issues. Also, let me know if you recieve a notification for this post.