I used this metering valve for well over a year with very little issues. However today I tried to use course media and it kept jamming. I upgraded the main fittings to 1" and it resolved this issue. So my suggestion if you are going to build this metering valve, use 1" plumbing instead of 3/4".
I also made a metering valve from 3/4" plumbing and a ball valve for the air inlet. 3/4" seems to work just fine. I did have problems with the gun however.. it kept jamming, You could see the media getting up to the gun, in fact the hose would completely fill with media from the gun to about 8" down from the gun but it wouldn't come out of the gun. What I ended up doing was removing the screw at the back of the gun and removed the air valve. Then removed the air fitting from the bottom of the gun and bored that passage to 5/;16" I it is 1/4" from the factory) Then I removed the nozzle and the orifice. The hole in the orifice is less than 1/8" so I bored it up to 1/8" and added an O ring to the ceramic nozzle where it mates with the gun. Filed about 1/16" from the threaded end of the gun so the nozzle would be the right distance from the orifice with the O ring on it. Reassembled the gun and tested.. It now flows media like you wouldn't believe even with the air pressure at 50-60 PSI. That little mod to the gun made it spray like the high dollar guns out there. Be aware though. I am running a 60 gallon 17 CFM @90 PSI compressor. If you don't want to bore out your orifice or your compressor can't handle a larger orifice, just try adding the O ring to the nozzle and make sure your nozzle is centered on the orifice
Well,I see that they are selling 'kits' on the worlds largest auction site for only $49.99 and free shipping!I figure theres maybe what,$20 bucks worth of fittings,depending on which valve you buy.Looks like they're selling a sink feed valve... Great video btw!
@@darkshadowsx5949 I'm sure very quickly. However, in this configuration, the abrasive is barely moving until it reaches the junction where the metering valve is, and then maybe 1 fps to the tube. Have since made two out of PVC. One for my cabinet and one for a hopper for outside use. Working great and cost about $10 each.
I've just done the same mod, for some reason I'm not picking up any media no matter how much PSI or how open or closed my valve is, any idea what im doing wrong?
@@1D10CRACY Yea, I've been playing around with air pressure/air valve and still nothings going to my gun, admittedly my media is old and has been lying a while so i suspect its the media thats wrong, ordered some new stuff so hopefully this does the trick.
I was having good luck with the siphon setup then built one of these and now the performance went south. I even tried going back to siphon without any luck. What am I doing wrong???
@@1D10CRACY I've also noticed that with my HF gun I have to loosen the nozzle a LOT! I can't tighten it down and get it to beat well. Any ideas on that?
@@1D10CRACY I found the problem. The gun it came with must be for fine media I took the tip off grinned the tip so more media could flow through as it started working much better also put just about 20oz of sand in it that helped I’m still tweaking it here and there to get more out.