SpudFiles

Thinking of building my own diaphragm valve.

Read up on the spudfiles wiki, and apparently 1/4" neoprene is common.

My problem is this: how much thickness for a max pressure of 180psi? Too thick and diaphragm probably won't even flex.

Haven't been able to find any other stuff that I could refer to so far, but am looking up to see if anyone posted any diaphragm cannons up there.

Thanks.

Limbeh

Depends on the diameter of your chamber and barrel, sprinkler valve diaphragms are usually well below 1/4" thickness.

Internal Diameter of chamber: 48mm
ID of barrel: 16mm
OD of barrel: 22mm

Unfortunately, since gardens are pracitcally non existent here, lawn sprinklers and sprinkler valves are also pretty hard to find here, so I can't really refer much to them. However, the idea of 6mm thick neoprene seems like waaaay overkill.....

Thanks.

Limbeh

If I remember well a typical 3/4" sprinkler valve has a diaphragm less than 2mm thick.

So that should mean that 3mm should be enough.

Thanks.

A couple of diagrams form the archive that might be of some help:

Thanks for the diagram, though I already found a diagram on the spudfiles wiki.

By far I don't find the working principles of spudguns hard to understand, its constructing it without much time, tools or working space that's the hard part.

Thanks.

The first diagram (animated one) will not work that way.
When you pilot it the sealing face will flap into the back.

the thickness need is really going to vary, most people don't bother finding the perfect thickness for a diaphragm, many people just glue the edges of the rubber disk to the wall of the chamber or even clamp the disk in a union, then they reinforce the area behind the barrel/port with a solid disk so the diaphragm wont burst at that area, this way it doesn't matter if the rubber can withstand the full pressure as long as the disk backing the rubber can

Jack, your diagram is full of DWV