MagDuct — Parametric Magnetic Ducting Quick Connect System

Motivation

Last year, I designed, printed, and installed an external exhaust system for my xTool P2 laser cutter and AC Infinity 6” Inline Duct Fan. Since then, I converted my Prusa MK4S+ to a Core One (enclosed chamber with exhaust), started soldering more electronics projects, and most recently purchased an xTool F2 Ultra UV laser engraver. So, my exhaust demand 4x’d in just the last few months!

Due to limited space and knowing I would probably only need 1-2 of those machines to process a job at any time, I did not want to permanently install a manifold with blast gates and splitters. I needed a system that could be quickly and easily reconfigured to accommodate only the active machine(s) and compactly stored when not in use. I also wanted the ability to easily iterate on the design and its parameters.

Solution

Design and print a custom reconfigurable exhaust quick connect system that achieves the following objectives:

• Fully parametric providing customization of all dimensions

• Magnetic

  • Standardized template for all components

  • Secure but detachable with intent

  • Embedded or surface mounted – the included model files embed the magnets 0.6 mm (3 layers at 0.20 mm layer height)

  • Easily sourced magnets

• Adapt various machines and ducts to the magnetic system as close to the source as possible

• Couple any two ducting sizes to each other

• Mount ducting to any surfaces by adapting to other mounting systems (e.g., RAM Mount)

• Extensible accessory support using the same magnetic template

Design

If you are using more than one ducting diameter throughout your exhaust system, determine which diameter will be the standard for connections throughout the system and use that consistently for the MagDuct template on all of your components. For example, the included design and model files are for the 99.0 mm diameter of the AC Infinity 4 in ducting that I use for the final run to my external fan. Also, I found 6 magnets to be the sweet spot for magnetic strength and reconfigurability, but you may prefer more. If you intend to use more than 6 magnets, determine that early as well. Lastly, consider polarity orientation and increment the magnet count in multiples of 2 so that you can alternate polarity maximizing the flexibility of the mounts on both sides. Reference the Customization section below for more details.

I have also designed adapters for all of my laser cutters/engravers and 3D printer converting them to MagDuct right at their exhaust. This provides several advantages like making it easier to organize and store ducting and lasers which are on mobile carts (e.g., xTool P2) while providing easier access for routine cleaning. Those adapters are linked in the Model section below with more details.

Customization

The Fusion files are included. You can customize the parameters (DESIGN | SOLID | MODIFY | Change Parameters) as necessary. When you open the Parameters dialog, first sort by name. The parameters most optimized for customization are favorited and commented in detail to help you. The non-favorited parameters should work as well but may require more tinkering to repair broken downstream features.

Critical Parameters

THERE ARE THREE PARAMETERS WHICH ARE CRITICAL FOR MAGDUCT COMPATIBILITY. THEY MUST REMAIN CONSISTENT WITH ALL OTHER MAGDUCT DESIGNS. In the Fusion files, these parameters start with '_' and include:

• _MagDuctDiameter - Outside diameter of the MagDuct template. If you have a duct that is already the right size for your ducting, you can most likely use that dimension for this parameter. But again, make sure that is the ducting you will use most throughout all designs you would like to be interchangeable.

• _MagnetCount - Total number of magnets used in each template. Default is 6 as discussed in the design section above.

• _MagnetSlotDiameter - Diameter of your magnets including tolerance

The MagnetSetback can be changed from the default of 0.6 mm — including down to 0.0 mm if you do not want to embed your magnets (not recommended for the mount ring since it's double-sided). In my testing, I found that 0.4 mm was a little thin to give the printer enough layers for smoothing over the bridging and provide enough strength to prevent the magnet from tearing out, but you may be able to dial this in better.

If you cannot get Fusion to work for you, please send me a message (see below) and I will post your requested model files at my earliest convenience.

Models

The designs provided on this Printables posting include MagDuct core components which provide the ability to adapt, couple, mount, and terminate exhausts with MagDuct compatibility.

Printables currently has a bug that requires you to refresh the page after clicking a link to view a specific model in the 3D viewer.

Adapters

   Slip

• xTool galvo laser engravers (e.g., F2 Ultra and F2 Ultra UV)

  • Adapt any of xTool's machines which accept a slip fitting straight to MagDuct. This model works for xTool F2 Ultra series machine and probably many others that I could not test. Please let me know if you can confirm.

    • xTool claims to provide 65.0 mm and 80.0 mm pipe connectors with the IF2 2.0. Both of the connectors I received have a 79.8 mm inner diameter on the machine/fan (unthreaded) end. On the threaded end, the inner diameters I measured were ~85.2 mm on the larger one ~60.6 mm on the small one. So, I think they had a typo in their video and it should have read 85 mm and 60 mm. 🤷

    • A test model for the slip fitting diameter is included to ensure your printer/slicer/filament combination will work with the design tolerance (0.1 mm). If not, just modify the tolerance parameter in the Fusion file until you get a good test fit.

• Duct Reducer or Expander (e.g., AC Infinity or xTool inline fans)

   xTool P2

   Prusa CORE One

• Use in combination with any of the generic accessories below to control the amount of heat allowed to escape through the exhaust during a print

Couplers

   Flexible ducting (e.g. AC Infinity ducting)

• Connect with duct clamps or cable ties

   Pipe/Rigid ducting (e.g., xTool pipe)

• Connect by screwing counter-clockwise just like the pipe connector included with xTool galvo lasers

Mounts

   Ring RAM Mount B Ball (1 in)

• The ring mounts are provided in 1U and 2U configurations. These numbers represent the number of magnets placed in each magnet slot. The 1U works great when mounted from above so that the ring is hanging down and the weight of the ducting prevents the ring from flexing. But in any other orientation, the thickness of the 2U ensures rigidity maintaining a solid magnetic dock on both sides of the ring.

Accessories

   Generic accessories included in this posting:

• Rotary Shutter

  • Control airflow in the 0-50% range

  • Includes detents for blind/tactile positioning on one side and continuous (non-detent) control on the other side

  • Test models for the rotor and stator hubs are included to ensure your printer/slicer/filament combination will work with the design tolerance (0.1 mm). If not, just modify the tolerance parameter in the Fusion file until you get a good test fit.

• Screen

  • Inlet or exhaust

• Cap

  • Completely block all airflow (e.g., maximizing the chamber temperature in a 3D printer)

   Vendor or use case specific accessories are in separate Printables postings:

• Fume Extraction Nozzle and Screen for soldering, etc.

Materials

• (6 per side per interface) 8x3 neodymium magnets – I used these from Amazon.com

  • Of course, if you customize the size of the magnet slots, you will need those magnets instead

Printing

See the attached .3mf for my settings and model orientation. I printed with Prusament PETG with the MagDuct geometry facing down on a PEI sheet with plenty of glue stick as a release agent (Prusa Filament Material Guide) to ensure the magnetic interface was as flat and smooth as possible.

   Supports

• Supports are only required for the two RAM Mount ball halves.

   Magnets

• If you plan to embed magnets during the print, ensure you have the following ready to go before starting the print:

  • Magnets

  • Pause(s) inserted at each layer immediately after an embedded magnet slot (the same layer that bridges to close the slot). These pauses should already be inserted in each of the Print and PrusaSlicer Project files but double-check before printing.

  • A plan for your desired polarity orientation.

    • With the default 6-magnet configuration, simply alternating North and South around the circumference of the base will allow proper part alignment at each 120° of rotation.

    • If you care about the aesthetics of the parts, also consider the seam placement in relation to the magnet orientation. I set seam alignment to rear for all of the parts in the PrusaSlicer Project files.

I prototyped on a Prusa CORE One.

Post-Processing

Remove supports and clean as required.

   RAM Mount

• Glue the ball together using the included pins for proper indexing. I sprayed the ball with a few coats of Plasti Dip which seems to help but is probably not necessary.

   Rotary Shutter

• Before assembling...the rotor will register in the stator detents more definitively if you apply heat (e.g., with a heat gun or blow dryer) to the middle section of the rotor allowing you to deform it by pushing against the hub just slightly while pulling back on the perimeter of the rotor so that it cools slightly concave applying pressure against the stator once assembled

• To assemble, align the rotor with the stator and very firmly snap the hub into the stator.

Questions

Please let me know if you have any questions (Messenger | Printables.com).

Shameless Plug

If this model helped you solve a problem, save some time, or in any way made your life a little easier then please consider clicking the Like button and posting your Makes! If it fell short after clicking on the title of the model, please let me know (Messenger | Printables.com). Either way, Thank you!

Related

   Complete exhaust configuration

      Adapters - Convert machine exhausts to ducting diameter and/or MagDuct

• xTool P2 Exhaust Duct Adapter (configured as 4 in)

• MagDuct xTool F2 Ultra UV Slip Adapter

• MagDuct CORE One Exhaust Adapter and Gasket

      Ducting

• AC Infinity 4" ducting

• AC Infinity 6" ducting

• xTool pipe (included w/ xTool IF2 2.0 and xTool F2 Ultra UV)

• xTool 72.5 mm ducting (included w/ xTool P2)

      Couplers - Convert flexible ducting or pipe/rigid ducting to MagDuct

• MagDuct Flexible Ducting

• MagDuct Pipe/Rigid Ducting

      Connectors - Convert ducting for attachment to inline fan or external surface

• Duct Expander (configured as 4 to 6 in expander)

• Ducting to Window Insert Connector (attached to a piece of 1/4" acrylic inserted in the channels of my double hung windows which allows for quick installation/uninstallation (configured as 148.0 mm (6") and 72.5 mm exhaust port)

      Inline Exhaust Fans

• AC Infinity 6" Inline Fan (High CFM)

• xTool IF2 2.0 Inline Fan (High Static Pressure/Suction)

      Mounts - Securely mount MagDuct components to a surface using a third-party mount

• MagDuct Ring RAM Mount (1 in)

      Accessories

• MagDuct Fume Extraction Nozzle and Screen - Direct smoke and fumes (e.g., soldering) into exhaust ducting

• MagDuct Generic Accessories - Control airflow volume and chamber temperature (e.g., enclosed 3D printers)

   xTool Accessories