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blane.c

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It seems to me that composite sheet goods need a simple method for incorporating hard points, that is because the sheets need a light core that is generally soft (like foam) or hollow (like honeycomb) and some structural areas need to transmit load through the sheet. This would facilitate gluing panels together in structural areas that would crush the soft inner structure of the panel(s) and facilitate adding other parts (landing gear and motor mount attachment come readily to mind). Round is an idea for hardpoints because it is easy to drill holes and making standard hard points of different sizes for different strengths and other needs would be simplest. Square and rectangular composite tubing would also have to be made to make building simple putting sawn flat panels together like the VP's in wood or the Vans and Hatz's in aluminum. Making solid or reinforced joining "L's", "T's" and compound shapes of those and others to make putting the tubing together is almost a complete business in itself.

Do you sleep?
 

Rik-

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It seems to me that composite sheet goods need a simple method for incorporating hard points, that is because the sheets need a light core that is generally soft (like foam) or hollow (like honeycomb) and some structural areas need to transmit load through the sheet. This would facilitate gluing panels together in structural areas that would crush the soft inner structure of the panel(s) and facilitate adding other parts (landing gear and motor mount attachment come readily to mind). Round is an idea for hardpoints because it is easy to drill holes and making standard hard points of different sizes for different strengths and other needs would be simplest. Square and rectangular composite tubing would also have to be made to make building simple putting sawn flat panels together like the VP's in wood or the Vans and Hatz's in aluminum. Making solid or reinforced joining "L's", "T's" and compound shapes of those and others to make putting the tubing together is almost a complete business in itself.

Do you sleep?

I asked this question but in a different manner, why do builders not use a mold.

shapes, designs and hard/soft edges are not an issue nor is a core in the composite building. It just seems that no one is Gung-ho about using a mold for composite aircraft.

It would be very easy to build a plug and then pop a mold off of it. Give the builder a top/bottom or LH/RH thst they have to bond together and boom they have a a fuselage. The composite can be “E” glass or “S” glass or combination there of. Resins can be polyesters and epoxy if cost are not as critical.

Fast, easy and in terms of man hours, cheap. Fiberglass and resins are cheap, $3/lb. Some want to do it the hard way though.
 
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Marc Zeitlin

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I asked this question but in a different manner, why do builders not use a mold.
And it's been answered in other threads. Having built two airplanes using moldless composite construction, and worked on many others using molds, and having built a number of molds, I don't see how anyone can claim that I should be able to build a plug (which is exactly the shape of the final product I'm trying to create), then fabricate a mold, then layup parts IN the mold. That's three things I've got to build/fabricate rather than one. NO-ONE can build a single molded part in less time than it takes to build a single part moldlessly.

Now, if someone's building three or more aircraft, THEN molds make absolute sense. But **** few builders build more than one identical plane at a time, at least in the E-AB world.
 

Rik-

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And it's been answered in other threads. Having built two airplanes using moldless composite construction, and worked on many others using molds, and having built a number of molds, I don't see how anyone can claim that I should be able to build a plug (which is exactly the shape of the final product I'm trying to create), then fabricate a mold, then layup parts IN the mold. That's three things I've got to build/fabricate rather than one. NO-ONE can build a single molded part in less time than it takes to build a single part moldlessly.

Now, if someone's building three or more aircraft, THEN molds make absolute sense. But **** few builders build more than one identical plane at a time, at least in the E-AB world.

True and we spoke about this but these guys want a plane that is a one of not a one off.
 

Rik-

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Scuttlebutt says that Dark Aero will fly this week or perhaps already has. Impressed that they came very close to their weight targets although it's not fully equipped or painted yet. Interested to see how it performs over the coming weeks.
Who may we ask, is the test pilot?
 

speedracer

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And it's been answered in other threads. Having built two airplanes using moldless composite construction, and worked on many others using molds, and having built a number of molds, I don't see how anyone can claim that I should be able to build a plug (which is exactly the shape of the final product I'm trying to create), then fabricate a mold, then layup parts IN the mold. That's three things I've got to build/fabricate rather than one. NO-ONE can build a single molded part in less time than it takes to build a single part moldlessly.

Now, if someone's building three or more aircraft, THEN molds make absolute sense. But **** few builders build more than one identical plane at a time, at least in the E-AB world.
I agree with Marc. I built a pair of Long EZ wings in three weeks.
 
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