GHQP Project

After researching a lot of designs via YouTube etc I came to the conclusion they are all pretty much the same concept. Only the construction materials and the way it attaches under or around the base of the spindle varies. As for attachment a popular method is to use strong magnets or Velcro. Fortunately my spindle motor has a round section protruding that allows me to make a simple collar attachment with one securing screw. You can see this from the photos. I chose Aluminium for the securing collar and clear acrylic for the hood top. I have yet to obtain appropriate material for the skirt. This will be a fairly stiff but flexible clear material and will be secured to the top section via a number of M3 screws. The vacuum hose connection is a piece of acrylic tube I already had that worked out to be a perfect size. In fact the way it all worked out, the hole I cut in the top acrylic section was such a tight fit I didn't have to use any adhesive to secure the tube into it, Just a few firm taps with a rubber head hammer. I used Aspire for the designing and my Sherline CNC Mill to make all the parts. A visit to the local vacuum cleaner store to purchase the hose and appropriate end fittings. I don't expect it to be perfect like some of the others I have seen but for me if it does a reasonable job that's OK.

I found the perfect material for the skirt at a local store that specialises in selling Foam, Rubber and Plastic material for outdoor and indoor use. They had a range of thicknesses, I chose 1mm. They couldn't tell me what the plastic sheet was technically called but it came off a roll about 2 Meters wide, it is UV protected and I imagine it is for outdoor use as wind and or rain blinds etc. Any way perfect for my dust extractor's skirt.
I cut off a 60mm parallel strip, wrapped it around the extractor's base and used some masking tape to hold it in place while I marked the location of the securing screws. Using a Hole Punch I made the holes for the screws, then marked and cut the skirt strips 30mm x 10mm wide. The skirt is secured in place using M3 Nylon screws with a plastic washer under the head. I just happened to have some of these, they are readily available form most electronic component stores. The photograph below basically explain how it all fits together. There are other thicknesses of clear skirt material available but my first tests with 1mm looks to work perfectly OK. The material costs for this project are so little it would be easy to make a range of hoods of different skirt styles and lengths to accommodate a variety of tool lengths and jobs as they come along. That's the beauty of having a CNC Router, duplication is so easy. I also like the fact of using all clear materials so that everything that's happening during the cutting process is viable from all angles. This type of skirt material and design might not be suitable for all materials being machined but it goes a long way to reducing cleanup and is very easy to work with. You will just find that due to its static properties dust and the like will stick and tend to mask the visibility through parts of the skirt as the machining process goes along. I hope you find this project of use when coming up with your own design.

I am using the hood for the first time today (April 23rd) machining a 3D image out of clear acrylic. I must say it works really well, I am so pleased.