blower: ensure presence and functionality

[Hurricos]

The seller does not have a blower for us.

The blower is shown here: https://laboratoryb.github.io/camfive/docs/Laser_Machine_INSTALLATION_MANUAL.pdf#page=8

Jake may have access to a blower.

[heaventwig]

For temporary exhaust routing, add a T junction to exhaust fan duct (PVC) overhead in garage, adjacent to exit from garage, and run flex tubing from laser, via rafters, to the T junction. Should have louver-style air handling valves to prevent backflow into either pipe, as the tube draws from (and could return to) house air.

[heaventwig]

Tim says he's trying vent fans from Vevor, says they are much quieter than the "big bois" and rated for twice the CFM (a rating which Tim questions, but the quieterness is nice).

[DaBlender]

My in line blower. 4” inch connection, not a lot of duct but it’s not expensive. I have not had any issues with it.

I forget the tool name to measure flow but would be handy especially to any safety check

[heaventwig]

As I prep tubing for exhaust, I'm curious about reasons for and against including a dust collection system somewhere along the way before the output air (with all of its fumes and combustion byproducts) gets pushed into the world at large...

[DaBlender]

A common method for air filtration is to use a pre-filter, an activated carbon filter, and a HEPA filter. This ensures that any unsafe particulates are caught in the filter, and the air will be much safer to breathe. You can either apply the filter to your laser cutter's exhaust or duct the air into a fume coffin.

…

On Sat, Sep 21, 2024 at 1:14 AM Venn Wylder ***@***.***> wrote: As I prep tubing for exhaust, I'm curious about reasons for and against including a dust collection system somewhere along the way before the output air (with all of its fumes and combustion byproducts) gets pushed into the world at large... — Reply to this email directly, view it on GitHub <#1 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABOGLWVDMRCLWR7P67AQ2U3ZXT6C3AVCNFSM6AAAAABOGI47FSVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDGNRVGAYDKNZRGA> . You are receiving this because you commented.Message ID: ***@***.***>

[Hurricos]

A common method for air filtration is to use a pre-filter, an activated carbon filter, and a HEPA filter. This ensures that any unsafe particulates are caught in the filter, and the air will be much safer to breathe. You can either apply the filter to your laser cutter's exhaust or duct the air into a fume coffin.

(cited)

I never paid attention to the exhaust filtering setup at Chatt*Lab (@ttsgeb?), but the consensus(¹²³⁴) seems to be that if you cut certain materials, lasers make nasty fumes, AKA "LGACs" (Laser Generated Air Contaminants). LGACs are primarily a concern when cutting certain metals or plastics⁵; if those types of materials are on the menu, and you're going to be cutting them in quantity, definitely get a filter.

Footnotes

1. https://www.instructables.com/Fume-Coffin-Laser-Cutter-Exhaust-Vent-Filter/ ↩

2. https://www.osti.gov/servlets/purl/1959231 ↩

3. https://community.glowforge.com/t/fume-coffin/8848/2 ↩

4. https://www.tlm-laser.com/info-centre/news-and-events/lasers-fumes-and-health ↩

5. https://ehs.oregonstate.edu/sites/ehs.oregonstate.edu/files/pdf/si/lasercuttersi.pdf ↩

[heaventwig]

Okay, so I definitely want to construct an exhaust vent filtration system. Next questions / todos are around defining specs for that device and system.

• define/identify CFM flow specification for exhaust ventilation from 150W CO₂ laser cutter

[DaBlender]

820m^3/h. Per manual. The coffin method is cool. Beware front filter being anything that melts.

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On Mon, Sep 23, 2024 at 8:24 AM Venn Wylder ***@***.***> wrote: Okay, so I definitely want to construct an exhaust vent filtration system. Next questions / todos are around defining specs for that device and system. - define/identify CFM flow specification for exhaust ventilation from 150W CO2 laser cutter — Reply to this email directly, view it on GitHub <#1 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABOGLWTXDGJWRYUWFWWY3ITZYACARAVCNFSM6AAAAABOGI47FSVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDGNRYGA3DCOBZGQ> . You are receiving this because you commented.Message ID: ***@***.***>

[heaventwig]

Beware front filter being anything that melts.

In this I read "leave ample room for exhaust to cool before it hits anything temperature-sensitive."

[heaventwig]

also noting here, for future reference, that 820m³/h is just under 490 CFM (cubic feet per minute).

[DaBlender]

I’ve seen paper cinder and fly into the vent, melting a hepa. Metal grid went before.

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On Mon, Sep 23, 2024 at 10:19 AM Venn Wylder ***@***.***> wrote: Beware front filter being anything that melts. In this I read "leave ample room for exhaust to cool before it hits anything temperature-sensitive." — Reply to this email directly, view it on GitHub <#1 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/ABOGLWVSQ6J5IUAZCG65XVLZYAPQHAVCNFSM6AAAAABOGI47FSVHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZDGNRYGQZDGMBWGI> . You are receiving this because you commented.Message ID: ***@***.***>

[heaventwig]

Adding to concept plan: metal wire mesh grid pre-prefilter.