M. Roberts
Cast Iron
- Joined
- May 11, 2021
Guys,
I am attempting to make a down draft table for my CNC mill. Hopefully my description will make sense. I have started with a standard sub plate, 18"x 48" x 1.5" thick. The plate comes standard with a blind 1/2-13 threaded hole every 1-1/4" on center. I have modified the plate by drilling a 5/16" thru hole, thru the center of the 1/2" threaded hole. In addition to that, I have added a staggered 5/16" thru hole with a 1-1/8" x 60 degree CS...so there isn't a lot of flat surface for dust to lay. Make sense so far? I have made and installed 2" tall x 1-1/4" round risers to space the sub plate off of the bed of the machine. There is a fabricated sheet metal tray that bolts to the back edge of the sub-plate, and tapers to the front (18" dimension)of the sub-plate, where two 6" ducts are connected. Each duct has 1250 CFM draw.
It works relatively well, but there is a noticeable difference in draw from the back of the table to the front. I thought that I could help this out by inducing compressed air to blow across the holes at the back of the plate, inducing a vacuum, and directing the dust towards the collectors...anyone have any thoughts? I will upload a picture when I have service...
Thanks,
Mark
I am attempting to make a down draft table for my CNC mill. Hopefully my description will make sense. I have started with a standard sub plate, 18"x 48" x 1.5" thick. The plate comes standard with a blind 1/2-13 threaded hole every 1-1/4" on center. I have modified the plate by drilling a 5/16" thru hole, thru the center of the 1/2" threaded hole. In addition to that, I have added a staggered 5/16" thru hole with a 1-1/8" x 60 degree CS...so there isn't a lot of flat surface for dust to lay. Make sense so far? I have made and installed 2" tall x 1-1/4" round risers to space the sub plate off of the bed of the machine. There is a fabricated sheet metal tray that bolts to the back edge of the sub-plate, and tapers to the front (18" dimension)of the sub-plate, where two 6" ducts are connected. Each duct has 1250 CFM draw.
It works relatively well, but there is a noticeable difference in draw from the back of the table to the front. I thought that I could help this out by inducing compressed air to blow across the holes at the back of the plate, inducing a vacuum, and directing the dust towards the collectors...anyone have any thoughts? I will upload a picture when I have service...
Thanks,
Mark