63mm / 2½" Butterfly / Throttle Valve Type Non-Clog Blast Gate for Workshop Dust Extraction Network

20May20

Marius-Bloemhof requested the CAD files:

(https://cad.onshape.com/documents/5425e358a4e266ea950b034e/w/fb495421e309359b374e4475/e/07ed980bcf8592c544c8964f)

Update 24Aug20:

I've posted a new design for a blast gate based on a ball valve:  print 137795

Update 03Jun20

I've posted a 100mm version of this blast gate based on a ball valve: print 137794 

After having unclogged the groove, in the commercially available blast gates in my workshop dust and chip extraction network, for the umpteenth time so that the gate closed fully, I decided that there had to be a better design. Naturally, I looked on Thingiverse but didn't find anything that seemed quite right (it doesn't mean that there isn't anything, just that I didn't find it!). I set to in Onshape with an idea, which, as I drew it, developed into two ideas, and then into two finished 3d printed objects. They both seem to work without clogging, and each has its own advantages and disadvantages.

This is the second idea, based on a butterfly valve, throttle-like assembly. This takes up less space than the sliding blade of the first design and is more of an anti-clog arrangement than the self cleaning action of the first design (the first design is print 137802)

Both designs are nominally for a 63mm (2½" ) rigid tube system, as shown in the photographs, but flexible hose of the same nominal size also fits.

In addition to printing filament you'll need 4 short M5 bolts of some kind and 2 short socket head M3 x 6mm and 1 socket head M3 x 10mm or 12mm bolts. The M5 bolts should self-tap their own threads into the holes printed into the Tube_1 frame, or you could use an M5 tap (or any other thread size that fits the hole). Likewise for the M3 bolts. The longer M3 bolt is used to hold the lever on the butterfly shaft. The holes may need to be eased with a suitable drill bit.

The lever has an arrow-like shape at it's tip, which shows which direction to rotate it to open the gate.

You need to print 2 tubes, the 2 halves of the butterfly (Butterfly_1 and Butterfly_2) and 1 lever for each gate.

Print Settings

Printer Brand:

Anycubic

Printer: 

Kossel

Rafts:

No

Supports: 

No

Resolution:

0.25

Infill: 

10% to 15% (doesn't matter)

Filament: Steadytech & Enotebook PETG Green & Red

Notes:

I use a 0.5mm nozzle, but I doubt that's important (except it's never clogged {so far}, unlike the 0.4mm nozzles I started with!)

Post-Printing =============

Assembly

To assemble the blast gate:

First drill out the 4 fixing holes in one of the tube frames so that the M5 bolts can pass through (we'll call this Tube_1). The bolts should be able to self tap into the undrilled holes in the second tube - Tube_2 (but these may need easing slightly for this to happen).

Fit together the butterfly halves to make the complete circular butterfly with shaft, and fasten with the 2 shorter M3 bolts, inserting through butterfly_1 first so that the bolt heads are in the counterbore.

Place the butterfly assembly into the shaft recess in one of the Tube frames so that the disc end stop is just outside the tube frame, and place the second tube frame over the butterfly. There are recesses in the tube bodies to allow the top and bottom of the butterfly to seat in its closed position and seal the air flow. These recesses should be opposite each other so that, with the butterfly shaft horizontal, one recess is at the top and the other is at the bottom (if the butterfly won't move, turn over one of the tubes).

Insert the 4 M5 bolts into the widened holes in Tube_1 frame and tighten into the holes in Tube_2.

Fit the lever onto the hexagonal end of the butterfly shaft so that it lines up with the axis of the butterfly (or any of the other angles you prefer) and hold in place with the longer M3 bolt,

Category: Machine Tools