ACTA/Ventilation

Projects
Participants	Ultratux
Skills
Status	Active
Niche	Mechanics
Purpose	Infrastructure

With the fan kindly donated by Urban Resort/ACTA, a generous amount of my time+effort and a heap of community money and patience, we have now installed and operational(*) a hefty, powerful, versatile ventilation- or air suction system. It encompasses six inlets in our space: {two in soldering area, one over general workbench, three in dirty room} and two future projected ones: one or more in clean room and one over kitchen area. The idea is to block/close inlets when not in use, thereby not losing suction power. The smaller kitchen inlet will be open all the time, however.

At the heart of the system is a large industrial fan powered by a ~300watt motor, which for reasons of noise suppression we built inside a padded wooden box which is suspended isolated with rubber rings to the ceiling in the dirty room. Still, the fan is audible/noisy, especially when cold (first 10-30 minutes). Lack of lubrication mostly. We're still looking into that.

As a future project enhancement, we'd like to automate and protect the system further by it having a temperature readout, cut-off overheat protection, and a timer switch. For this purpose a temperature probe+module has been purchased already, and the probe installed on the fan engine. The rest however, needs to be designed and built. We already have a solid state relay for it.

Some pictures I took of the finished inlets and how they ought to be blocked by the red plastic 'cups'.

Introduction

We can probably get our hands on a big centrifugal fan. It needs to get an outlet to outside, and presumably also some conduits as inlets as we want maneuverable pipes for exhausts in the space. The fan will not be silent; it's not the type that is. Uncertain is how much noise it makes, but it will for certain be too noisy to have in the main space. So it needs to go in one of the small rooms. To make a neat hole in the outside wall might require a specialized company ('diamantboring'), or it may not, but we currently have no right tooling to make a round hole of 100-120 mm dia through a 30cm thick wall. Plus, hacking through leaves a not-round hole we'll be forced to cement up *from* *outside*. Having the hole done by a diamantboor has the added benefit the hole is neat and doesn't need patching up.

Update

This weekend, a few milestones were reached. First one was that we managed to bolt the empty fan casing that was built onto the ceiling above the 'dirty room'. Second was to mount the fan motor assembly there with the help of a pulley system. Third was to deploy a 10m flexible tube to connect its outlet to one of the -much smaller- air/ventilation holes already available in the space. This was needed to finally being able to hear it in action, thus judging sound- and vibration levels and amount of air pressure/suction buildup. We were dying to hear it/see it in action... As it turns out the fan is a bit noisy when it is cold. After 10-15 minutes running, it quiets down quite nicely and is barely audible anymore when sitting in the space. Which is excellent ! When the ceiling is closed and a door is in the doorframe, it will get better still.

Now, what needs to be decided is: Will we quickly drill a hole through the concrete or leave it like this, either temporary or definitively. Remko does not quite object to using the ventilation hole in the wood. However, it is much further away, we'll need a scaffolding to patch the hole up again, and it might displease our downstairs neighbor [maybe]. If we leave it like this it means we need another 10m flex tube (90 euro) which is about what we'd pay for renting the drill too. Apart from that, the now-temporary situation is our 160mm tube going into the 100-120mm outlet tube, which severely hampers airflow. So even if temporary, I have a strong desire to widen the outlet hole to 160mm if we take this route.

It seems other tenants are contemplating renting a concrete drill together, lowering cost. I will try to find out more tomorrow.

Update 2

It was deemed okay (mainly by just myself but not exclusively) that at least for the short run, the exhaust through the vent hole works fine, provided the narrowing of the conduit gets avoided. I took it upon me to do that today, it took some acrobatics and a full tube of acryllic kit but now the duct directly exits the building without narrowing. If in future a separate drilled hole is deemed necessary, it is easy enough to cut this tube at 1 meter and reconnect it to the original inlet in the wood panel above our windows. Justa voiced that the exhausted air would be sucked in again by the adjacent (100cm) other inlet. I don't think that would happen so quickly, but we always have the option to block that inlet, either by temporarily closing it or by blocking it altogether. The other two inlets over the soldering corners are far enough to not suffer from exhausted air at all. They will only bring in fresh air mixed with fine-dust particles from the A10 highway nearby, have no fear about that. ;-)