May 24, 2019
Description
Hi,
This is an safety valve for my workshop dust collection system based on 50mm pipes.
With this valve you won't incidentally destroy your installation when you forget to open inlet or clog your hose.
This happened to me more then once, that I forgot to open blast gate and turned on the vacuum. It usually ended in crushing my plastic barrel - not permanently - but still a lot of additional work to straight things up.
Also while unseeing small devices like orbit sander, there are only tiny holes to suck the air and sometimes it was not enough to prevent of crushing my barrel.
The same thing happens when you clog your hose.
For all those "accidents" - and probably others - I've design this safety valve.
There is a moving piston inside, that is held by the spring. During normal operating of dust collection system, it stays closed. But when the suctions builds up over setup threshold, it will open and allow air to flow.
You can regulate when the valve should open, by twisting the screw.
You will need M3/M4, long screw - like 25-30mm, two washers and a nut. You will also need a spring - you can with spring from pen, but it can be too soft. You could also probably go with rubber band, but I haven't tested it.
First you need to drill trough a hole on top of the shell - there should be printed one layer diaphragm (that's because it was prepared for "no support" printing).
You need to bend one end of the spring in to the hook and connect it to piston. Then find the proper length of the spring and connect it with screw like on the picture above.
There is a tiny grove on the piston, that can be used to put o-ring seal. It's optional, I don't use it.
Just put it on the least used inlet in you duct and you are done :)
More parts of my workshop dust collection system (SShopDC) you can find here: https://www.thingiverse.com/Saur0n/collections/sshopdc
Quick presentation of entire system on YouTube: https://youtu.be/4z4FXlIJgac
License:
Creative Commons - Attribution - Non-Commercial
Saur0n
