Scubapro MK10 SPEC Boot Molds - Free if you'll use them!

[Wiznutaggie]

Without dampening your enthusiasm, let me offer a caution regarding using the Mk10 boot for a Mk20.
If you look at your photo, you'll see how stretched the boot is compared with the much narrower diameter that it's designed for.

The boot works because the cylindrical pocket between the two "walls" is a flexible chamber as the piston moves. With valve opening and closure during breathing (and to a much larger degree upon reg pressurization) the piston head moves up and down. Therefore the volume of the ambient chamber changes by a measurable amount. The existing boot works because the "roof" of the chamber is very thin and flexes in and out accommodating volume changes inside the ambient chamber. When the piston head moves up, the lube oozes out of the holes, but is contained in the boot. When the piston head moves down, that lube goes back in the holes, and the roof becomes concave.

When the boot is stretched as much as it has to be by the Mk20, that chamber is significantly diminished in volume. If there's not enough volume to allow uninhibited lube movement in and out of the holes, IP will fluctuate mid-breath.

My second observation is that in the Mk20 pictured, you'll note that the ambient holes are very close to the bottom of that groove. Therefore, the boot's "walls" will necessarily partially occlude the ambient holes, and further constrict lube movement.

I don't think that model Mk20 will work as well with a boot, because there needs to be room for the boot walls to seal on either side of the ambient holes.

Sorry to be the bearer of potentially bad news.

I've had those same thoughts, but I just might be bored enough to pack it and see what it does for kicks and giggles! The thicker walls of the boot obscures about half of the ambient chamber holes, but there is still access to the thinner expansion portion of the boot.

 

[James79]

I've had those same thoughts, but I just might be bored enough to pack it and see what it does for kicks and giggles! The thicker walls of the boot obscures about half of the ambient chamber holes, but there is still access to the thinner expansion portion of the boot.

Well, I prototyped the mk25 boots @rsingler mentioned (ended up being not worth the required changes), and make mk20 boots (and an adapter trim ring if it has the scalloped turret). Let me know if you need some.

Best,

James

Borrowed Mk20 UL with boot (blue silicone) and scalloped turret trim ring (yellow TPU):

 

[rsingler]

And @James79 , I should have known it was you.
I thought your boot was great! If anyone can create a SPEC Boot for a Mk20, it's you.

 

[DAF]

This was an experiment. I have a Mk 10 that I don't really use so I thought I'd try something. I took a piece of 1 1/4 in diameter thin wall heat shrink tubing, cut it to fit the groove, slipped it on and shrunk it. It appears to work. However as I said this was an experiment only.

 

[p_kos]

And @James79 , I should have known it was you.
I thought your boot was great! If anyone can create a SPEC Boot for a Mk20, it's you.

I have an original MK20 boot (as do some other folks after buying out Charlene’s stock) if anyone wants yo use it for patterning.

 

[James79]

I have an original MK20 boot (as do some other folks after buying out Charlene’s stock) if anyone wants yo use it for patterning.

That's how I made my mold... I borrowed one from Lex for measurments.