Ventilation for my Snapmaker 2.0
2021-Apr-07, Wednesday 06:30 pm![[personal profile]](https://www.dreamwidth.org/img/silk/identity/user.png){kind=small}
chebeWhen I got a 3d printer, that is also a laser cutter, I knew I'd have to sort out a half-way decent ventilation system. So I picked a spot near to an existing vent. I'm not sure how common this situation is, so I best explain it a bit.
This house I'm in is over forty years old, and made of bricks. It was built to be heated by an open-fireplace-powered wet central heating system. As a result every room in the house has an always-open air vent to the outside, ensuring air circulation even when the windows are kept shut. But it is a very basic arrangement, literally utilising a hole in a cavity block brick, with both sides left open on the inside and outside wall surfaces. These holes are then covered with air vent grilles. (These houses did not have insulation, and they definitely didn't have air conditioning. Houses are no longer made this way.)
The enclosure of my printer comes with a fan powered exhaust and accordion exhaust duct. The documentation says the duct diameter is 75mm. The bag the duct comes in says 3.2". We had 4", and 2" pipes, but 3" pipes are incredibly non-standard here. The 4" pipe fits perfectly in the cavity block ... cavity, so all I really needed was an adapter. Again, 3" is not standard, I could not buy a suitable adapter. But I could print one.
I had a look around and found adapters claiming to be what I needed, but after printing them (for 11 hours) discovered that they were the wrong size. Thankfully I could see they had been generated from another project, the Parametric Dust Collector Adapter. I discovered that the Customizer tool existed, and that I could use it to customise the model. At least in theory. (I started off jobs a few weeks back, am still waiting on them to finish.) Instead I found an article on How to run Customizer on your own Computer, which basically boils down to installing OpenSCAD.
I did that, customised the model to fit around the outside diameter of the 4" pipe, and in the inside diameter of the 3.2" exhaust duct. It works! Though it is a bit loose on the 4" side and a bit tight on the 3.2" side. I think I missed the section about changing the shrinkage calculation, because it seems to be set for ABS and I printed in PLA. But it actually worked out well. I'm going to leave the duct always attached to the adapter, and only connect the adapter to the pipe in the vent when I need to use it. When not in use I can remove the adapter and put the vent grille back in place. And just like that, I have a half-way decent ventilation system.
OpenSCAD file settings;
taper = 0
facet_epsilon = 0.01
clearance = 1.017
wall_thickness = 4
od_pipe_2 = 70
od_pipe_1 = 110
len_pipe_2 = 30
len_pipe_1 = 35
transition_length = 20
This is the pre-existing cavity block vent, right above the location of my printer. (Please excuse the weird paint colour situation. I sized down the vent grille for this and haven't tidied up the paint yet. Am also considering longer curtain poles to just hide the whole thing.)
The grille can be unscrewed and moved out of the way. Here you can see the inside of the 4" pipe which now lives in the cavity block, safely wedged in with insulation. It is not a thick wall, you can see the back of the outside grille through the pipe.
This house I'm in is over forty years old, and made of bricks. It was built to be heated by an open-fireplace-powered wet central heating system. As a result every room in the house has an always-open air vent to the outside, ensuring air circulation even when the windows are kept shut. But it is a very basic arrangement, literally utilising a hole in a cavity block brick, with both sides left open on the inside and outside wall surfaces. These holes are then covered with air vent grilles. (These houses did not have insulation, and they definitely didn't have air conditioning. Houses are no longer made this way.)
The enclosure of my printer comes with a fan powered exhaust and accordion exhaust duct. The documentation says the duct diameter is 75mm. The bag the duct comes in says 3.2". We had 4", and 2" pipes, but 3" pipes are incredibly non-standard here. The 4" pipe fits perfectly in the cavity block ... cavity, so all I really needed was an adapter. Again, 3" is not standard, I could not buy a suitable adapter. But I could print one.
I had a look around and found adapters claiming to be what I needed, but after printing them (for 11 hours) discovered that they were the wrong size. Thankfully I could see they had been generated from another project, the Parametric Dust Collector Adapter. I discovered that the Customizer tool existed, and that I could use it to customise the model. At least in theory. (I started off jobs a few weeks back, am still waiting on them to finish.) Instead I found an article on How to run Customizer on your own Computer, which basically boils down to installing OpenSCAD.
I did that, customised the model to fit around the outside diameter of the 4" pipe, and in the inside diameter of the 3.2" exhaust duct. It works! Though it is a bit loose on the 4" side and a bit tight on the 3.2" side. I think I missed the section about changing the shrinkage calculation, because it seems to be set for ABS and I printed in PLA. But it actually worked out well. I'm going to leave the duct always attached to the adapter, and only connect the adapter to the pipe in the vent when I need to use it. When not in use I can remove the adapter and put the vent grille back in place. And just like that, I have a half-way decent ventilation system.
OpenSCAD file settings;
taper = 0
facet_epsilon = 0.01
clearance = 1.017
wall_thickness = 4
od_pipe_2 = 70
od_pipe_1 = 110
len_pipe_2 = 30
len_pipe_1 = 35
transition_length = 20
4" pipe to 3.2" duct adapter printed in PLA
Photo by chebe
Printed adapter with 3.2" duct attached by clamp
Photo by chebe
Adapter attached to both duct and 4" pipe
Photo by chebe
This is the pre-existing cavity block vent, right above the location of my printer. (Please excuse the weird paint colour situation. I sized down the vent grille for this and haven't tidied up the paint yet. Am also considering longer curtain poles to just hide the whole thing.)
Air vent grille above my printer enclosure
Photo by chebe
The grille can be unscrewed and moved out of the way. Here you can see the inside of the 4" pipe which now lives in the cavity block, safely wedged in with insulation. It is not a thick wall, you can see the back of the outside grille through the pipe.
The vent grille mostly unscrewed and exposing the vent pipe for access
Photo by chebe
The adapter, with attached duct, fitted into the vent cavity and secured to the vent pipe
Photo by chebe
View of the duct from enclosure to vent
Photo by chebe
