Spec Boot For Mk-15

[lowviz]

That might be a reason to cast the boot in urethane instead of silicone. I have used the Reoflex also. ...

Reoflex looks interesting.

Any issues with it?

 

[rhwestfall]

Not sure the MK-5 ever had the chamfer in the body for a band. The 5's I've seen were all "SPEC" styled with the "two stage" holes in the ambient chamber, large outer, and smaller inner....

Bands for a MK-10 (and a MK-5 should there be that style) would be very interesting to have available again.

The one style of the MK-10 had a "nub" on the inside of the ring that "indexed" it to the proper alignment. On the one I have, the nub is broken off....

From the manuals, there were at least two generations/styles used.

 

[uncfnp]

One Mk 10 boot on the way

Bob. Didn't know there were two variations. Already packed and mailed but I am pretty sure no nub and no evidence of damage on the one sent to lowviz. Hope it works.

 

[rhwestfall]

Sorry about derailing this discussion to a MK-10.....

Here is the MK-10+ and the MK-10.

Note the MK-10+ installation directions vs the MK-10

There is another one, but I can't seem to find it now.....

 

[lowviz]

... Good question for the Smooth-On guys. BTW they are really helpful and friendly.

That was my experience with them too. Long phone discussion describing the part.

They are sending cured samples of VytaFlex (40, 50, and 60) and PMC 770 for urethanes, and Smooth-Sil 950 for a silicone. That will give me something to compare before I take the boots up to Reynolds Advanced Materials.

Edit1
I'm pretty sure that the boots are made from one of these: Corry Rubber - RubberTech


Edit2
This is cool: https://www.agilent.com/cs/library/applications/5990-9878EN_AppNote_4100FTIR_Orings.pdf

Edit3
Out for quote: FTIR Laboratory If it is anywhere near reasonable, I'm going for it.

 

[Couv]

I'm not sure what material the original boots were made from; and to be honest, it does not really mater as the polymers of today (including the Tigger/Vis Super Boot) are likely to be superior. One word of caution though, if the boot you produce is silicone based you do not want to pack the chamber with silicone grease as the boot will absorb some of the silicone oil causing distortion of the boot.

I would bet the original boots were rubber and that's why so few of them have survived.

 

[lowviz]

I share your suspicions.

Job one is to find out what they were made of to avoid any unforeseen surprises and (mostly) to bolster my likely choice of a similar and superior urethane.

There is a simple touch contact non-destructive test that a properly equipped laboratory can do in minutes. (see above) I've requested a quote from RTI to determine the "class" of elastomer, in other words, which group in the Corry Rubber link. If nothing else, it would be nice to know.

We press on...

 

[raftingtigger]

Duplicating the part is one thing, making a better replacement is another. Given everything I have seen I think I can make a suitable and usable boot for a MK 5. Not sure I want to complicate my rigs with them as I don't do silty or below 45 deg water. OTOH, it might be nice for my pony. If I make a mold for the MK 5 I'll share. I'm very interested in the material chosen in the end.

 

[raftingtigger]

Reoflex looks interesting.

Any issues with it?

None I have found, at least one of my active 109A 2nds has a diaphragm cover made of it. I like the feel of the Oomoo or Smooth Sil better, but for the SPEC boots something other than silicone would be better.

 

[lowviz]

.../... If I make a mold for the MK 5 I'll share. I'm very interested in the material chosen in the end.

I got a quote back from RTI for doing the analysis. A tad pricey, but I REALLY want to know too. Looks like in about two weeks I'll have a definitive answer for the MK15 boot.

At that point, we can pick a suitable material. Thanks for all your help (and several others) with this!