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  #1  
Old 09-08-2008, 11:09 PM
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Default Braking and heat

I'm concerned about braking and heat. Too many stories about struts failing for my liking.

Whenever i think about heat i think of it in three ways
Radiant
Conductive
Convection

I thought that radiant was the major problem, seems as though i was wrong. Just talked to a real schmart guy who talked to a velo driver who had his bow fail after doing quite a few high speed taxi tests in a cross wind.

Remember i want to get rid of the words "you gotta remember"

After close inspection of the gear it was discovered that the axle bolts had made the holes in the strut elongated.

So i am going to make a Heat shield as follows

two layers of 1 16th aluminum behind the hub, out side the hub one layer will be to stop radiant heat from the brake disk and caliper, a fiberfrax or similar material will be added between the 2 layers of the aluminum to shield the second sheet from radiant and conduction heat from the disc side layer and this piece will be fashioned to be in the air flow inside the wheel pant. I will probably reduce the thickness of this material as it gets farther from the axle.

convective heat transfer will be controlled by adding chevrons that this real schmart guy will draw on my wheel pant in the pressure recovery area on top to allow air to escape through the natural tendency for hot air to rise.
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Enjoy the build,njut av byggandet, godere il costruire, nyd bygningen, geniesse den Bau, apolafse tin kataskevi, disfrute la construcción, curta a construção, Pidä hauskaa rakentamisen parissa, bouw lekker,uživaj grade?inaslajdaites postroikoi, geniet die bou
dust

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  #2  
Old 09-09-2008, 01:25 PM
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G.Norman
 
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Location: Lathrup Village, MI
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Default Re: Braking and heat

Quote:
After close inspection of the gear it was discovered that the axle bolts had made the holes in the strut elongated.
1 - Were the elogated holes made "before" the bolts were installed due to a mistake or poor craftsmanship?
2 - Were the elongated holes made by heat?

3 - Were the holes made by loose bolts due to bad bolts/nuts, improper torque, etc?

4 - Who made the bow? There's still a lot of those defective bows out there.

Note: the bow heat problems recorded have been above the axle where the "radiant" heat had transferred directly across from the rotor. Your double heat shield may be a bit overkill but a neat idea if the fiberfrax doesn't slip out between. Then you have made possible new problems. I've heard good results from applying the heat shields. There's some cool ides for venting the heat from the wheel pants. I remember one with a small NACA in the front and louvers on the top.
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Old 09-09-2008, 01:44 PM
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Default Re: Braking and heat

As is normal - near impossible to get complete information on anything canard.

My solution should solve all possible problems - ima thinkin
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Enjoy the build,njut av byggandet, godere il costruire, nyd bygningen, geniesse den Bau, apolafse tin kataskevi, disfrute la construcción, curta a construção, Pidä hauskaa rakentamisen parissa, bouw lekker,uživaj grade?inaslajdaites postroikoi, geniet die bou
dust

maker of wood, fiberglass, foam dust, metal bits and one day a Cozy will pop out and swiftly whisk me from meeting old friends and family to adventures throughout the world
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  #4  
Old 09-15-2008, 03:51 PM
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G.Norman
 
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Default Re: Braking and heat

Quote:
My solution should solve all possible problems - ima thinkin
What's your take on those failing nose gears. Seems there's room for lots of improvements here.
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  #5  
Old 10-01-2008, 02:15 PM
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Default Re: Braking and heat

Well, as normally seems to be the case - after reading 100,000 posts on the internet i found the real skinney(info) on heat shielding off internet.

I finally feel that i have a handle on how to make proper shields.

My shielding technique does include alumium, but not as part of a shield as it works more as a conductor than a shield, but as a radiator.

one layer of thin SS, then a layer of a fiberfrax LIKE material to stop radiant heat from the SS and then a layer of aluminum to radiate heat from surfaces i think extra heat will build up in. Of course if i use that layer of aluminum it will have an air gap from the fiber frax LIKE material and i will supply the area air to get rid of the heat.

If this procedure is followed I can't imagine gear struts failing or cowlings melting

radiant
convective
conduction

protect for all three

This strategy is not just for the brakes, but also and especially for the 1400F preturbo exhaust pipes
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Enjoy the build,njut av byggandet, godere il costruire, nyd bygningen, geniesse den Bau, apolafse tin kataskevi, disfrute la construcción, curta a construção, Pidä hauskaa rakentamisen parissa, bouw lekker,uživaj grade?inaslajdaites postroikoi, geniet die bou
dust

maker of wood, fiberglass, foam dust, metal bits and one day a Cozy will pop out and swiftly whisk me from meeting old friends and family to adventures throughout the world

Last edited by Dust : 10-01-2008 at 02:58 PM.
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