Cleaning the filters
A long time ago I wrote a post about the different things we have learned to do for dust control in the shop because we recognize that it is the dust that kills tree makers. The filters in our cyclone system are a lot larger than the filters in the dust mask Rod is wearing in this old picture. But anytime you use filters to clean your air, the filters get dirty. (Imagine that…) So we have to clean the filters. Rod did that job again this week.
First off, I want to say it is ideal to vent the cyclone outside and not use filters at all. That way any of the fine dust that gets through the system will not be recirculated into our shop air for us to breathe. It is also much cheaper than buying, setting up, cleaning and replacing filters. But the problem is that Clear Vue Cyclone system puts out over 1400 cubic feet of air per minute. That means we need to pull over 1400 cubic feet of air per minute back into the shop.
That is fine in the summer, when the grass is green, the birds are singing, and the air temperature compatible with comfortable human life.
That is NOT fine when the temperatures are below freezing and it can get so cold it makes you cough to breathe. (People in the southern climes talk about not wanting to lose all their cool air in the summer. We, for some reason totally unfathomable to us, have never had that problem…)
Our set up allows for us to switch from one mode to the other. Out the wall in the summer. Using the filters in the winter. While it isn’t a difficult switch to make, it is a bit of a hassle making sure the connection is leak proof, so Rod doesn’t do it all the time. His rule is that if he is working in the dirty room and he needs to wear more than one layer of sweaters to stay warm, he switches to filters. And the days are starting to get a tad chilly around here now. At least the mornings are.
So before switching back to winter mode, cleaning the filters was a job that needed to be done. When you read about cyclones, etc. you read that very little fine dust goes into the filters. That is true, but it is also true that a very small percentage does get through. When you make a LOT of fine dust, as we do with the sander and especially with the grinder in the dirty room, that percentage adds up over the months and cleaning the filters is a job that has to be done two to three times a year.
It means pulling the filter box out of the cyclone room (we put it on wheels for such a time as this…) taking off the front and even releasing the filters from the box so we can turn them around to get all sides. It is about a two hour job.
In commercial filter systems, they have a set up that blasts air backwards through the filters to clean them. We designed our filter box so that we can run air backwards and blow the discharge out the window, but we have found that it doesn’t really work that well. The pressure from just reversing the flow is far lower than the blast the commercial units use and it doesn’t seem to move much dust out of the filters. So we vacuum them off. While not ideal, it does make a difference.
And no, they don’t get back to being sparkling brand new at the end. I’m sure the dust left in the filters impairs the air flow to a certain extent, but the idea in keeping your lungs safe is overkill – if kill is an OK word to use when you are describing safety… This unit moves a LOT of air. There is a LOT of surface area on these two filters (which, by the way, cost a LOT of money…). So even with the probable reduction in air flow due to increased back pressure caused by some residual dust in the filters, we will still have more than enough to clean the air in our shop.
And we know that it does, because we have a Dylos dust meter. And when the cyclone is working in the winter, the air particle count in our shop is lower than in our house. So the time and effort and expense in putting in and maintaining the dust collection system is worth it because, amazingly enough, both Rod and I enjoy breathing…
So, after taking a couple of hours to clean everything, Rod decided it was warm enough that he didn’t need to switch to the filters after all, and he went and worked outside instead… He’ll enjoy it as long as he can!