Rubber sheet for diaphragm

[runsongas]

because it is a source of possible premature failure if you don't change it out, so you end up wasting time having to do an extra rebuild later on. it also costs very little if you are punching them yourself or buying them in bulk from trident.

 

[rob.mwpropane]

because it is a source of possible premature failure if you don't change it out, so you end up wasting time having to do an extra rebuild later on. it also costs very little if you are punching them yourself or buying them in bulk from trident.

In a pinch can be flipped?

 

[Jim Lapenta]

In a pinch can be flipped?

Not in most regs. That one in the one photo with the indentations and raised center started out flat. When I service a reg the diaphragm is the 1st item removed and the 1st one installed. The old one gets taken out by poking a hole in it and lifting it out.
When I send the old parts back with the reg they go in a bag labeled do not re-use. The hole ensures it can't be.

 

[rob.mwpropane]

Not in most regs. That one in the one photo with the indentations and raised center started out flat. When I service a reg the diaphragm is the 1st item removed and the 1st one installed. The old one gets taken out by poking a hole in it and lifting it out.
When I send the old parts back with the reg they go in a bag labeled do not re-use. The hole ensures it can't be.

That's what I've always been told... but the why is what gets me? I mean, it looks brand new? Is it jsut the indentation that causes it to be "old"? I have a hard time telling which side was even down after I take it out (although some are fairly easy to tell).

 

[Centrals]

Liability.
DIY is another story.
I always kept the used diaphragm or HP seat if they look ok after servicing myself.

 

[Couv]

If one is going to DIY a diaphragm, take note of the the thickness as well as the diameter. One manufacturer may use a different spec than other manufactures. As a matter of fact, Scubapro uses a different thickness of diaphragm in the MK17/19 than they do in a MK11/18 kit. Considering how similar the internals of these regs are, it would be easy to unwittingly make that error.

My friend @rsingler has a saying, "It (scuba regulator maintenance) ain't rocket science. But it is precise."

 

[Diverspoint]

I just saw this, so sorry about the late answer. Would stiffness play a role here? As some materials are much stiffer than others.

Silicon is much floppier than EPDM

 

[rsingler]

Stiffness is less critical than you might think, as diaphragm movement is so small.
It is more critical in the diaphragm of the environmental seal above it, because this translates into "effective diameter" applying ambient pressure to the transpiston, and thence to the main diaphragm. Too stiff a material for the env seal, and IP matching as you descend will lag.