My DIY, self-cleaning, 2 1/2" blast gate

[Johnathan Giordano]

I am building a PVC-based dust collection system (2 1/2") and decided to build my own blast gates that would (1) be self cleaning, (2) require minimal adapters, (3) be simple in design and (3) be reasonably priced. I realized that one can use two flanges as the blast-gate body which yields a very compact design. Please see the attached picts. I used two 2" spigot flanges made by Valterra which I picked up at a local RV store for about $3.50 each. A 'spigot' flange means that the flange-end is a male which will fit into a PVT tee without needing any adapter. The other nice thing is that 2-1/2" hose will fit nicely over the inlet of the flange. Thus, the PVC-side and hose-side are handled nicely without having to resort to adapters. I used Formica for the blast-gate blade. The 5x7" sheets cost 25 cents a piece at Home Depot or Lowes. I used tongue-depressors ('craft sticks') as the spacers. I could have used Formica for these, but really did not enjoy working with laminate and found the craft sticks so much easier to drill and cut. As part of the construction I had to drill a hole in the Formica. I did not have a hole saw and was amazed at the price for a single hole saw at Home Depot or Lowes. I wound up buying a complete set at Harbor Freight for $7.99 and to my surprise I was actually able to cut a decent 2-1/8" hole with it. Please have a look at the picts. Any comments would be appreciated. Thanks.
BlastGate1.jpgBlastGate2.jpgBlastGate3.jpgBlastGate4.jpgBlastGate5.jpgBlastGate7.jpgBlastGate8.jpg

[Johnathan Giordano]

Additional picts...
BlastGate9.jpgBlastGate10.jpgBlastGate11.jpg

[Bob Cooper]

I don't need any blastgates but very nice write up and nice clean design

[Larry Frank]

need some blast gates and these look great...Thanks

[glenn bradley]

Great show and tell. Thanks for posting it.

[Rick Potter]

Two days ago, I had two large boxes of sewer fitting, DC fittings, small blast gates, etc., spread out on my bench, trying for the 50th time to figure out what goes with what.

It was a timely post for me. I ran out of time, and put it all away again for next time. I still cannot figure out the best way to go from 2" PVC through a blast gate, to a large shop vac fitting.

Nice job, by the way.

[Johnathan Giordano]

I still cannot figure out the best way to go from 2" PVC through a blast gate, to a large shop vac fitting.

Hi Rick - Thanks for your comments. The easiest way I've found to go from shop-vac hose to 2" PVC is with a flexible coupling as shown below. The nice thing is that the coupler comes with the hose clamps on each end.
.Flex Coupling.jpg

A more elegant and less expensive approach is to soften a piece of PVC pipe in boiling water and either enlarge or shrink one end as required. This approach is explained nicely by Bill Pentz here http://billpentz.com/woodworking/cyclone/pvc.cfm

[Rick Potter]

Thanks Johnathan,

I have tried that also. It works, but what I really want is some way to reduce the number of fittings, a blast gate combo that would let me plug in my standard shop vac hose to a gate.

What Rockler or Peachtree should do is make a blast gate that fits 2" PVC on one side, and has a normal shop vac fitting on the other. I'll bet they would be good sellers.

If somebody already makes one of these, please let me know. I am gathering parts for a 2" shop vac system for my shop, that will go right next to my DC blast gates.

[Johnathan Giordano]

I agree with you 100%.

Perhaps in the not too distant future, we will be able to 3D-print parts exactly to spec. I can imagine HD or Walmart having Kiosks where you upload your design and they crank it out for a few bucks. That would eliminate the 'not enough customers to make it economical' roadblock that current suppliers likely face. Then again, having past 60 a while back, this may be an option for my son ;-)

Check out http://www.yeggi.com/q/pipe+fittings/?s=tx and http://grabcad.com/library/blast-gate-15in-round