Laser Cutter Venting System

NOTICE:
Laser cutters are expensive and dangerous.
All of our laser cutters are ducted and require venting.
YOU MUST turn the ventilation system on before you use any of the cutters.
Do not leave them unattended. It is a fire hazard.
Some jobs take a long time to run. If you need to run to the bathroom or something, find someone to watch it for you.
A full tutorial is in progress: Laser Cutter HOW TO
60-watt Operation Training Video

• Designed and built by Brant H, John K, Anna K, Geoff L, Markus S
• Installation started on 9/9/2023, mostly done by 3/29/2024
• Extension of existing laser lab exhaust to the East Room
• Added slide gate dampers to all machines

• p031 motor nameplate volts = 230
• p032 motor nameplate hertz = 60
• p033 motor overload current = 6.0 (motor nameplate is 5.4)
• p034 min freq hertz = 0
• p035 max freq hertz = 60
• p036 start source = digital input
• p037 stop source = digital input
• p038 speed ref = internal pot/knob
• p039 accel time = 30 sec
• p040 decel time = 5 sec
• p041 reset defaults = no

• Designed and built by Markus
• Installed by Markus, Brant, Tony, Kathy C, Marcin, and Robert S.
• In the direction of air flow:
  • Four 4“ round inlets at the bottom
  • Stage 1: 24x24x4 MERV 12 furnace filter
  • Stage 2: 24x24x12 HEPA cartridge filter
  • Stage 3: 60” x 16.5“ dia. Can-Filter 150 activated charcoal (http://canfilters.com/filters/can-filters/can-filter-150.html)
  • One 8” bellmouth fitting outlet at the top
• Installed on Space Improvement Day, Oct 28, 2018
• One can be removed from each box for replacing filters/parts
• Markus estimated the charcoal filter would need replacing in about 2-3 years
• Existing 2 HP fan increased to from 48 to 54 Hz on VFD above Craft Lab ceiling
• Initial (clean) filter box drop approx. 0.50“ w.c.
• Laser Cutter Exhaust Filter Pressure Drop Monitor installed 12/09/18
• Laser Cutter Exhaust Filter Pressure Drop Monitor modified 7/23/23

• None

• Sterilite plastic container with two 4” atrium grate drains and a DIY charcoal filter
• Seems to be working OK as of May 2nd, will check again
• PVC cement failed on 5/12/17 while BrandonM. was cleaning around the machine
• Filter repaired and cleaned on 5/30/17

• Filter by Brant

• 4“ subsoil drain pipe with charcoal sandwiched between two layers of 1/8” hardware cloth
• Installed on the 50 watt, works OK

• Filter by Brant

• 4“ subsoil drain pipe with charcoal sandwiched between two layers of 3/4” fiber roll media
• Instantly plugged up, very restricted
• Air assist upgrades completed at the same time
• Individual controls at each laser cutter and air valves/regulators for each machine

• Filter by Brant
• Air dryers, separators, and filters provided by ChrisH
• Extra help by TomGz, ShaneT, and TonyW

• Added a filter box to the laser cutter exhaust (pollution control unit)
• Two sets of (2) 16x20x1 furnace filters; one set has activated carbon poured over it
• Activated carbon available from aquarium supply stores
• Two 4“ inlets (50 & 60 watt) and one 4” outlet connection
• No change to the on/off switch in the room
• Increased fan speed on motor drive from 30.0 to 49.0 Hz
• Increased static pressure at unused duct drop from 2.0 to 5.0 inches water column
• EDIT: Did not work, little to no flow at the inlets to the filter box, even after caulking all the joints and resealing the drawers. MDF is just too porous/leaky. Disassembled and abandoned on 6/4/17.

• Filter box by Brant

• Minor change to controls only
• Replaced low-med-high with on-off turn switch (low is the only setting we need)
• Replaced indicator lights which kept burning out?
• Removed pressure switch
• Added emergency stop
• Plastic box replaced with more rugged, metal enclosure

• New controls and vinyl signage by Brant

• Fan: 2 HP Dayton Fan, Model Unknown
• Control: Mitsubishi FR-A204 Variable Frequency Drive with 3-speed switch (off-low-med-high)
• Ducting: 4“ aluminum flex to machines, 6” reinforced galvanized to fan, with custom muffler
• Discharge location: Outdoors, louver on north side of building
• Machines vented: (3 in use, 4 connections max)
  • Laser Cutter (50 watt)
  • Laser Cutter (60 watt)
  • Laser Cutter (40 watt)

• Fan, ducting, wiring, 4-button switch, and muffler by Tom Gralewicz
• Pressure switch, fan indicator light, and enclosure by Brant
• Blog Post! http://milwaukeemakerspace.org/2014/01/laser-cutter-venting-system-version-5-0/

• Fan: 1 HP Central Machinery Fan, Model 94029 (Purchased from Harbor Freight)
• Control: On/Off Switch
• Ducting: 4“ PVC and 4” Flexible Plastic Duct
• Discharge location: Outdoors, louver on north side of building
• Machines vented: (2)
  • Laser Cutter (25 watt)
  • Laser Cutter (60 watt)

• Fan and ducting by Tom Gralewicz, Lance Lamont, and Matt Wittmann
• Frequent replacement of the fan motor brushes were a hassle.

• Fan: 1/2 HP Vacuum Pump
• Control: Mitsubishi FR-A204 Variable Frequency Drive
• Ducting: 1-1/2“ PVC
• Discharge location: Loft
• Machines vented: (2)
  • Laser Cutter (25 watt)
  • Laser Cutter (60 watt)

• Added a flexible plastic duct and tee with slide gate dampers for second machine.

• Fan: 1/2 HP Vacuum Pump
• Control: Mitsubishi FR-A204 Variable Frequency Drive
• Ducting: 1-1/2” PVC
• Discharge location: Loft
• Machines vented: (1) Laser Cutter (25 watt)

• The shorter duct run improved air flow over Version 1.0.

• Fan: 1/2 HP Vacuum Pump
• Control: Mitsubishi FR-A204 Variable Frequency Drive
• Ducting: 1-1/2“ PVC
• Discharge location: Loft
• Machines vented: (1) Laser Cutter (25 watt)

• Version 1.0 was scrapped and much of the ducting rerouted when the Laser Cutter (25 watt) was relocated to the south wall of the Workshop.
• For a very brief period of time we used a shop vac to exhaust the machine.