Collecting the dust from my floor mounted power tools I have a nice two bag dust extractor, permanently connected to these machines by a system of four inch piping and valves. However up until now i have had to use a portable vacuum cleaner to collect the dust from the portable power tools that i also use.
so i had the idea to make connection that would allow me to connect a length of normal vacuum cleaner hose to my 4 inch piping at the blast gate. Having already assembled this one ill re do the build for you in line drawings.
What i used...
-- Wood square just larger then the diameter of the dust extractor hose/ coupling valve (6 inches x 6 inches x1 inch)
-- Band saw
--Portable sander (rigged up side down)
-- Drawing compass
-- Duct tape
-- long wood screw
-- Drill press (ensures vertical hole) or Power drill
-- Countersink bit
-- Drill bit to suit screw size
-- Posidrive Screwdriver
-- Drill hole saw
-- Straight edge
Connecting to dust extractordust extractor, via the four inch hose and blast gate couplingblast gate coupling
Step 1: Shaping the Wood
-- Take the piece of wood, and place the blast gate coupling on to it so you can draw the internal diameter of the 4 inch pipe onto the wood roughly in the centre.(image 1)
--- Then using tangent cuts on the bandsaw cut down to the line. (image 2.)
Step 2: The Vaccuum Hose
Now take the length of vacuum cleaner hose you intend to mate with the 4 inch hose, and place its end flat in roughly the centre of the circle of wood you now have - once again trace the diameter of the hose on to the wood.(image 4)
Step 3: Find the Centre of the Marked Hole
Now you need to find the centre of the circle you have traced from the vacuum pipe.
Using a straight edge draw to lines - any where inside the circle, each having their beginning and end touching the circle (eg: diagram 1)
Step 4: Find Circle Centre 2
Take the first line (diagram 2) lets call it a-c.
Place one point on "a", extend the compass to approximately 3/4 of the lines length and swing it up wards scribing a curve out side the green circle (eg: black curve)
Now with out adjusting the compass width repeat the scribe from point "c" (eg: green curve)
Your black and green curves should intersect at some point along their radius.
Step 5: Find Centre Circle 3
Now repeat the process scribing curves from point "a" and point "c" as you have just don't in step 2, this time, however scribe the curves below the blue line - as showing in diagram 3 at point "d"
Step 6: Find the Centre Circle 4
Now draw a line that runs across the intersections of both curves above and below the blue line.( eg: purple line in diagram 4)
You have found one axis of the centre - now all you need to do is repeat the entire process on the red line.(diagram 5)
Where the two intersect lines ( purple and orange) cross is the centre of the circle.(diagram 6)
Step 7: Vacuum Hose Hole Cutting
Choose the appropriate hole saw blade, ( do so when fitted in to the hole saw) and set the saw in to the chuck of your drill press ( or power drill)
Secure the wood block in a vice, and line the centre drill of the hole saw up with the circle centre.
Cut out the circle - you may need to turn it over to get right through - ensure you line the hole saw centre drill up with the same hole.
Step 8: Attaching the Hose
Hopefully if you have got your hole saw matched properly, the end of your vacuum cleaner hose will now push firmly into the small hole you have cut in the center of the wood disk.
If it does not - as was the case in mine, then simply wrap duct tape around it until it does fit firmly in the hole.
At this juncture in the assemble of my systems the wood disk decided to crack ( bad choice of wood grain on my part) - so I added two screws - visible on the left and right here to keep the circle together)
Now select a wood screw that is long enough to pass through the wood out circle, through the vacuum cleaner hose and back in to the wood circle - to hold it in place.
Drill the hole, counter sink it, and then screw in the screw.( see below )
Step 9: Home and Hosed.
Now you should have an animal that some what resembles that shown in the pictures below.
Simple turn on the dust extractor, open the blast gate most of the way but leaving about 1cm in the pipe to act as a retainer.., place the wooden circle in and it will be retained here until the suction is turned off.
Now figure out how you are going to attach the other end of the hose to your power tools....