|Project by MrLaughingbrook||posted 12-25-2014 09:53 PM||3786 views||28 times favorited||8 comments|
Blast Gates and Manifold
While I’ve always tried to stay dust safe and clean in the workshop, I’ve recently overhauled the whole system and am very happy with the results. I took the plunge and bought a large cyclone and decided on some fixed ducts with blast gates to replace the single 10 foot flex hose that I used to move around.
I owe the design of the blast gates to several others, thanks. One thing I might add is on how I cut the holes and other procedural steps.
I wanted a good tight fit on the “4 inch” PVC pipe with a 4.215 outer diameter. I thought a jig saw would make a mess and could not find a hole saw or circle cutting jig that matched my requirement so I did as follows:
A precise template to drill a hole in my router base:
Install a dowel pin:
Mark the boards to facilitate keeping track of the inside faces and drill through both boards at the same time.
Drill center holes in the blast gate body material ($3.99 MDF core shelf material) to receive the guide pin.
Drill a starting hole for the router bit using the template and pin:
Set the router/compass’ bit to just over half of the thickness and cut from each side (drill a hole in the base and use the base as a receptacle for the center pin to keep the cutout from moving around as the hole is completed, double sided tape will keep the surround mounted securely):
Resulting gate body pieces now a sets of four:
Cross cut each piece (cut with inside face down to keep mirror images). A gate is made from a piece from both boards. Remove any melamine from edges in concert on end pairs to facilitate glue on sides during later step.
Cut the short junction ducts from PVC square:
Glue with Gorilla Glue as the expanding will fill and make a nice tight fit:
Clean up with a chisel (an end cap screwed to a base plywood helps hold the work):
Round over with a router bit and pilot bearing on the inside lip:
Make some sides to connect the body from hardboard and the gate from acrylic. Space the middle with a piece of paper added to allow the gate to slide easily. Clamp and glue the final assembly:
Four blast gates complete:
Build a manifold from six inch S&D PVC with branches for the gates:
Install the gates and connect flex hose with purchased couplers at each tool:
I also purchased the terminating blast gate from Clear-Vue, two four inch ducts at the end of the main six inch duct will draw from the drill press and bandsaw when it arrives.
*this happened back in March 2014, just posting now due to comment on another project about how clean my shop appears…