Thanks for the heads up on the Dylos. I took a look at the price though and by the time I bring it into Canada, it will be prohibitive.
Ok. would you do an experiment for me please. Take a bright lamp and turn it on in your shop. Cut some MDF or something and see how much dust you show in the beam of light from the lamp. Now measure the air with your Dylos. Run your filter stack until you do not see particles in the lamp beam and measure again. Please tell me what you saw and the values you measured.
For me, I routed a piece of MDF. I had dust all over the place. Within the first foot of the lamp in the light beam there was a fair amount of dust. I ran my filter for two hours and went back and took another look. There was no dust in the beam of light. I'd love to know how that measures on your Dylos. I'm sure that this is a pretty objective evaluation but it's all I've got.
Thanks for the help.
Brilliant idea! Never thought of a do it your self dust tester but I think it can be done on the cheap. I'm a retired EE and a genuine DIYer in the shop. I save a huge amount of money by forward thinking.In fact I enjoy making tooling and stuff more then building furniture or cabinets.
All of the dust particle counters work on the same principle of using a laser and measuring the light from back scattering. For our needs we don't need a $4600 lab instrument. Dylos charges about $200 for the 1 micron. I bought the .5 Micron unit a long time ago . They did an excellent job of getting the price down but its still a bit much for a home shop.
I have a very large back order of all sorts of projects Wife, kids etc so probably about 6 months before I can complete this. It takes me about 3 tries to get a project where I like it. I can already see a bunch of ways to do this in my head. A really fun project. The killer is measuring the back scatter in a wide enough range to be useable. It might be as easy as using a photo transistor and a Harbor freight Digital Volt meter. Cost here for parts about $10-$20. Things rarely work out but we shall see. Keep in contact with me.
If there are any EE's here jump in.
I also have a lot of test gear for airflow. If you have duct work you can roughly estimate your CFM by making a Slack Tube manometer. That is simply a 1/4" clear plastic tube about 4' long bent in a U shape. Fill it half way with water and stick one end inside the duct . This will give you a pressure reading( SP) which relates to CFM.
The matching CFM instrument is also a bit pricey at about $120 but CFM estimates are probably good enough for most folk. No way to DIY for the CFM meter that I know of.