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  #21  
Old 10-02-2018, 10:44 PM
crabandy crabandy is offline
 
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Hoping to add to and not de-rail this thread.

I installed these baffle/cylinder wraps on my parallel valve engine, I ended up removing them for testing etc. I can tell you they stick like you wouldn't believe on the cylinder fins, Its an amazing composite. After more flying and testing I then used Ultra Black to stick the same sheets of RTV impregnated glass I pulled off my cylinders to my lower baffles, I've been satisfied with this compromise. This undoubtedly leaks more air than DanH's method but seems to work well for my parallel valve setup.
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  #22  
Old 10-03-2018, 06:20 AM
BillL BillL is offline
 
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Location: Central IL
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Default Extension tube . . .

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Originally Posted by JDA_BTR View Post
When you buy it in the can does it come with some kind of straw like WD40 does? Seems the 190ml caulk tube is the easiest to use? This comes in a lot of different packages.....
I made my own. Expanded some poly tubing to form a flare so the pressure would not extrude the tube out of the tip. Sealed with some soft wax. Started with 5/16, with a 1/4" tip.
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  #23  
Old 10-03-2018, 08:17 AM
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DanH DanH is offline
 
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Quote:
Originally Posted by rvbuilder2002 View Post
It is a very small amount of surface area coated with a very flexible/compressible material.

My experience is that with the wraps pulled tight it has no influence but I imagine an even coating as in your photo would be the optimal plan.

Especially if you are measuring gaps with a feeler gauge
That's a fair point, and I'm not gonna bore everyone with a homily about "better". The factory crew has the unenviable task of developing methods and instructions for everyone, which includes the least capable builders. Then they get to explain it repeatedly on the help line. The prescribed stripes (to prevent wear, not seal) are simple, and if they can get the builders to actually fit the baffles tightly, it's good enough. Airplanes shall fly. Grins will be seen.

As for us nut cases, zero leakage is the goal. It's a mental illness with a justification

BTW, it's important to differentiate between merely gasketing the standard cylinder wraps, and extending the glued-on gaskets further up and around the cylinders and heads. The first is just improved sealing. The second has a bunch of interesting effects, some of which, depending on application, are quite experimental.

Regardless of which path is taken, please, take the time to fit the baffles, not just drape them on the engine.
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Last edited by DanH : 10-03-2018 at 09:01 AM.
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  #24  
Old 10-03-2018, 09:11 AM
rvbuilder2002 rvbuilder2002 is offline
 
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Location: Hubbard Oregon
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Quote:
Originally Posted by DanH View Post
The factory crew has the unenviable task of developing methods and instructions for everyone, which includes the least capable builders. Then they get to explain it repeatedly on the help line. The prescribed stripes (to prevent wear, not seal) are simple, and if they can get the builders to actually fit the baffles tightly, it's good enough. Airplanes shall fly. Grins will be seen.
Exactly

Testing has shown that the methods described in the latest construction manual work quite well and are achievable by amateur builders.

Can it be optimized or made better? In many cases the answer is yes, and done on purpose so the true experimenters have something to
"experiment" on
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  #25  
Old 10-03-2018, 01:58 PM
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F1Boss F1Boss is offline
 
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If the goal is to stop fretting and keep all the air where it belongs, gasket the whole inner surface of the wraps.

[/quote]

I used this process on my Whisper Quiet TCM550 a few months ago. Now the dang 'normally over-temping' engine runs with CHTs around 300 or LESS most of the time. Had to block off some of the oil cooler too as the oil went to 160 or so in cruise.

Now my steady work is modifying the rubberized stuff to bring the temps up to 320 or so. Very odd, but the front cyls behave normally temp-wise, but the center and aft cyls are the cold ones...

BTW I did not 'cover' the rubberized stuff with any aluminum stuff. I don't think it will blow off - but I could be wrong...stay tuned.

I guess I need a house call from Dan...I must have done something wrong.
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  #26  
Old 10-03-2018, 02:51 PM
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DanH DanH is offline
 
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Quote:
Originally Posted by F1Boss View Post
Now my steady work is modifying the rubberized stuff to bring the temps up to 320 or so. Very odd, but the front cyls behave normally temp-wise, but the center and aft cyls are the cold ones...
A few piccolo tubes might lead to enlightenment.

Quote:
BTW I did not 'cover' the rubberized stuff with any aluminum stuff. I don't think it will blow off - but I could be wrong...stay tuned.
I assume you mean glass wrap extending above the 9 and 3 o-clock plane. Not likely to blow off there, as static pressure pushes it toward the fins. Underside of the cylinders? Tell me more.

Quote:
I guess I need a house call from Dan...I must have done something wrong.
You got beer?
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