One-way blow hose?

[B-Rye-oNeR]

Searched and found a few things, but not what I was looking for. I remember somebody posting a homemade one-way blow hose awhile ago, but I couldn't seem to find it. Anyone know where I could get one, or possibly make one myself? That hot/toxic air blowing back when working a large piece can't be good for us. Maybe we can come up with a simple design to cut out this problem. I was thinking a T seal with a rubber cap , kinda like on a respirator, (but then you'd have to find a way to cap the outlet when you wanted to blow.) I'm not the best with the actual physics of this, so I'd need some help to complete that thought. Anyone else have any ideas, or seen anything like this?

[James Sowell]

the big problem i can see happening is that you need the pressure to relieve when you heat closed items or they expand or contract and effectively end up sucking or blowing on your work as they are heated

[B-Rye-oNeR]

found this aquarium one way valve, would still need a way to relieve pressure, and still be able to blow. I will start drawing I guess.

[James Sowell]

i could see a small hole in the hose or say drilled into the hose side of that valve working to relieve pressure but still allow you to blow into it and make pressures when needed

[twisteddman]

I am pretty sure you can buy exactly what you are looking for from glasscraft. It looks like the valve thing you got there , but has a filter inside. Its designed to put on your blow tub e. Dude in my shop has one

[art vandelay]

http://www.usplastic.com/catalog/ite...HuYaAuoN8P8HAQ

millions of these out there. just search check valve followed by your diameter blow hose.

im sure you can buy them from glass suppliers but in my experience those companies usually just send items like tho one above and mark it up 5x price

[faded]

Stop sucking.

[Firekist]

i've looked for and tried to design something for this.. but.. i'm still at a loss. it'd essentially be a 2 way check valve. one valve that closes the exit when you blow, then closes the inlet(mouth side) and opens the "exhaust" side. .. seems like the product is out there.. but there's a lot to wade through.

a simple check valve will cause backpressure, not relieve it.

can't find anything at glasscraft's web page.



if you aren't working at the bench, you could have a large container with a hose in and out. the large container would be a buffer/diluter for any backflow. not a great fix to your concerns.. but.. it'd be better. if you use a larger diameter hose, you would also have less backflow due to the volume of the hose.

[menty666]

Not really my area of faked expertise, but couldn't you get two extra long lengths of hose and make up a water filled container to hook them to so you're blowing through the water? Making two glass barbs shouldn't be that tough, and you can always put a drain in the bottom of the vessel to drain it once in a while.

Of course that doesn't help with the backpressure problem, but at least it would look cool

[art vandelay]

buy two check valves and a t fitting if you want the air to be able to escape. its that simple.

order will go mouth, blow hose, check valve, small length of hose, t with check valve going to nothing(for air to suck in but not blow out), blowhose, red hot crackpipe.

if you need me to draw the schematic in crayon i can

[art vandelay]

or this contraption http://www.talkglass.com/forum/showt...-one-way-valve

[Doctor Dee]

These are the classics-
I've made them all; they work fine.
valve for blowing contaminated apparatus.pdf
yet another safe blowhose.pdf
another toxic-proof blowhose .pdf

-Doctor Dee

[B-Rye-oNeR]

Thanks for the info!

[PyroChixRock]

Interesting. If you solve this problem, let us know!

[mtownglassart]

The way we did it was to have an open line through a part in a foot peddle to the hose and when the button we engaged it sealed this line and used air from an air compressor tank to blow in to the hose. See pic. Works perfect. I could send you the part numbers off this to make your own devices.

[raul24]

Use a t-bore stopcock.
https://www.scilabware.com/en/pyrex-...way-ptfe-key-1

[mtownglassart]

Is this to swich the airflow direction or to turn off completely by hand? This looks useful