Raising the skylight

[High Country 69]

I didn't want to rob nates thread so I'm starting this one here.

 

Randy could you put up some pics of raising your skylight specifically how you faired it back down into the wings. I'm thinking of just building new butt ribs that are higher on the top and flat on the bottom with a completely open hole to view the fuel sight tubes through. if you were to do it again would you keep the changed dimensions you have or add/remove some of the height? also how you made the turtle deck attach would be great as well?

 

I've been having thoughts of making a carbon fiber transition piece that goes across above the front carry through tube that would have the two compound bends molded into it, this would allow for easily attaching a clear windshield to the front and a darker skylight to the rear and eliminate the bends in the windshield so hopefully they would last longer. has anyone done this yet?...thoughts?...pics?

 

-Robert-

[EDMO 1078]

Robert,

If you can visualize two aluminum angle strips (maybe less than 90 degrees) put back to back and riveted or bolted/screwed to the front carry-thru tube and covered with a shallow U-shaped, almost flat, light aluminum strip, where the WS and Skylight meet. Could be sealed with proper sealer for Lexan? Only one angle needed at rear of skylight.

Does this help or confuse?

I would like to see a drawing of what you are thinking of - could have some compound curves in fg/cf???

EDMO

Edited 4 Aug 2013 by Ed In Missouri

[High Country 69]

Robert,

If you can visualize two aluminum angle strips (maybe less than 90 degrees) put back to back and riveted or bolted/screwed to the front carry-thru tube and covered with a shallow U-shaped, almost flat, light aluminum strip, where the WS and Skylight meet. Could be sealed with proper sealer for Lexan? Only one angle needed at rear of skylight.

Does this help or confuse?

I would like to see a drawing of what you are thinking of - could have some compound curves in fg/cf???

EDMO

Ed, Ive seen this done to attach two pieces of lexan together (see pics)  my reason for using the FG/CF would be to eliminate the compound bends in the lexan and hopefully make it last longer. you could easily mold two small channels pointing fore and aft to insert the lexan pieces into if you wanted then just rivet or screw it all together. I'm having a real difficult time removing the paper from my 26 year old lexan so i'm going to just replace it anyway so I'm thinking if I just make it exactly what i want to (one piece wind screen and skylight for now) to use as a mold and just lay up the carbon fiber directly to the lexan. you could then just remove it trim it up add a small spacer down the center the thickness of the lexan you wish to use and add another flat piece to the bottom of that which would make the small channels pointing fore/aft to slip the lexan into. did that make any sense? the whole thing could then be attached to the the front carry through just as before.

 

My main concern at this time is how to fair the raised skylight back down into the wing

[EDMO 1078]

This may sound silly, but got to ask: Why would you want to raise the skylight when you are not raising the overhead tubes? Does your head go between the tubes? I would not want my head to be between the tubes - that sure looks like a bump and a headache if something happens!

I raised my crossovers 6 inches, and put an upward bow in my overhead tubes, and wish I had bent the overhead tubes even higher. And I am only 5-8, but my seats are higher.

Hope you post photos when you have made the mods.

EDMO

Edited 5 Aug 2013 by Ed In Missouri

[High Country 69]

the tubes go down the center between the seats so your head will not hit them I'm 5'10" and don't hit them anyway but with a headset on it will just about rub against the lexan so I want a tad bit more room to make it more comfortable, I then plan to put foam around the tubes to keep from banging them too hard in the event of a rough landing. I have to have my seat higher than most with this same airframe to accommodate the flapperon mixer which I have relocated under the left seat to allow for more baggage. 

[EDMO 1078]

the tubes go down the center between the seats so your head will not hit them I'm 5'10" and don't hit them anyway but with a headset on it will just about rub against the lexan so I want a tad bit more room to make it more comfortable, I then plan to put foam around the tubes to keep from banging them too hard in the event of a rough landing. I have to have my seat higher than most with this same airframe to accommodate the flapperon mixer which I have relocated under the left seat to allow for more baggage.

The gray foam tubes that are used for waterpipe insulation are great - already split down the middle and stick back together - You can cover with something if you don't like the color, or get the tubes that kids use in the swimming pool in lots of colors, but you have to cut and glue them.

Anything helps to keep your head from being dented - Like the helmet that everyone hates!

I have a $600 helmet that will only be worn for the first test flight!

EDMO

[birddog486 21]

I raised the buttribs 2.5" for some added headroom.

[EDMO 1078]

I raised the buttribs 2.5" for some added headroom.

Looks Good - Bet that turtledeck fits a lot better than trying to bend Lexan...

EDMO

Robert, Spruce and probably local vendors sell some kind of liquid that is supposed to remove old paper without hurting Plexi. I wonder about soaking it in soapy water?

ED

Edited 6 Aug 2013 by Ed In Missouri

[SuberAvid 617]

I didn't try to build a smooth fairing for the transition, I just made trim from aluminum sheet bent 90 degrees and used a crimper to curve it. One strip covers the skylight on each side and one strip goes the other direction to cover the wing on each side. The attached pictures show it.

[skypics 89]

Robert

I have a model b with .060 in front and tinted .125 on top. I split it at the crossover at the top of the windshield.

Regarding fuel monitoring:

I can see the fuel level to the last drop through the fiberglass tank wall at the wing roots. I have no header tank.

John M

[SuberAvid 617]

Robert

I have a model b with .060 in front and tinted .125 on top. I split it at the crossover at the top of the windshield.

Regarding fuel monitoring:

I can see the fuel level to the last drop through the fiberglass tank wall at the wing roots. I have no header tank.

John M

Hi John,

 

I would consider installing a header tank just as a safety measure so you always have fuel in a turn, possibly low fuel or slightly out of coordination.  I have even run one tank completely dry until I was getting air before switching tanks when I was low on fuel and wanted to squeeze the last drop out of one tank and then monitor it where I could see it on my other tank.  I don't worry about my engine shutting down as long as I have a header tank to take up the gap in fuel flow.  The header tank is a very good safety for more than one situation.